c-typeck.c revision 260918
1/* Build expressions with type checking for C compiler. 2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 4 Free Software Foundation, Inc. 5 6This file is part of GCC. 7 8GCC is free software; you can redistribute it and/or modify it under 9the terms of the GNU General Public License as published by the Free 10Software Foundation; either version 2, or (at your option) any later 11version. 12 13GCC is distributed in the hope that it will be useful, but WITHOUT ANY 14WARRANTY; without even the implied warranty of MERCHANTABILITY or 15FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 16for more details. 17 18You should have received a copy of the GNU General Public License 19along with GCC; see the file COPYING. If not, write to the Free 20Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 2102110-1301, USA. */ 22 23 24/* This file is part of the C front end. 25 It contains routines to build C expressions given their operands, 26 including computing the types of the result, C-specific error checks, 27 and some optimization. */ 28 29#include "config.h" 30#include "system.h" 31#include "coretypes.h" 32#include "tm.h" 33#include "rtl.h" 34#include "tree.h" 35#include "langhooks.h" 36#include "c-tree.h" 37#include "tm_p.h" 38#include "flags.h" 39#include "output.h" 40#include "expr.h" 41#include "toplev.h" 42#include "intl.h" 43#include "ggc.h" 44#include "target.h" 45#include "tree-iterator.h" 46#include "tree-gimple.h" 47#include "tree-flow.h" 48 49/* Possible cases of implicit bad conversions. Used to select 50 diagnostic messages in convert_for_assignment. */ 51enum impl_conv { 52 ic_argpass, 53 ic_argpass_nonproto, 54 ic_assign, 55 ic_init, 56 ic_return 57}; 58 59/* The level of nesting inside "__alignof__". */ 60int in_alignof; 61 62/* The level of nesting inside "sizeof". */ 63int in_sizeof; 64 65/* The level of nesting inside "typeof". */ 66int in_typeof; 67 68struct c_label_context_se *label_context_stack_se; 69struct c_label_context_vm *label_context_stack_vm; 70 71/* Nonzero if we've already printed a "missing braces around initializer" 72 message within this initializer. */ 73static int missing_braces_mentioned; 74 75static int require_constant_value; 76static int require_constant_elements; 77 78static bool null_pointer_constant_p (tree); 79static tree qualify_type (tree, tree); 80static int tagged_types_tu_compatible_p (tree, tree); 81static int comp_target_types (tree, tree); 82static int function_types_compatible_p (tree, tree); 83static int type_lists_compatible_p (tree, tree); 84static tree decl_constant_value_for_broken_optimization (tree); 85static tree lookup_field (tree, tree); 86static tree convert_arguments (tree, tree, tree, tree); 87static tree pointer_diff (tree, tree); 88static tree convert_for_assignment (tree, tree, enum impl_conv, tree, tree, 89 int); 90static tree valid_compound_expr_initializer (tree, tree); 91static void push_string (const char *); 92static void push_member_name (tree); 93static int spelling_length (void); 94static char *print_spelling (char *); 95static void warning_init (const char *); 96static tree digest_init (tree, tree, bool, int); 97static void output_init_element (tree, bool, tree, tree, int); 98static void output_pending_init_elements (int); 99static int set_designator (int); 100static void push_range_stack (tree); 101static void add_pending_init (tree, tree); 102static void set_nonincremental_init (void); 103static void set_nonincremental_init_from_string (tree); 104static tree find_init_member (tree); 105static void readonly_error (tree, enum lvalue_use); 106static int lvalue_or_else (tree, enum lvalue_use); 107static int lvalue_p (tree); 108static void record_maybe_used_decl (tree); 109static int comptypes_internal (tree, tree); 110 111/* Return true if EXP is a null pointer constant, false otherwise. */ 112 113static bool 114null_pointer_constant_p (tree expr) 115{ 116 /* This should really operate on c_expr structures, but they aren't 117 yet available everywhere required. */ 118 tree type = TREE_TYPE (expr); 119 return (TREE_CODE (expr) == INTEGER_CST 120 && !TREE_CONSTANT_OVERFLOW (expr) 121 && integer_zerop (expr) 122 && (INTEGRAL_TYPE_P (type) 123 || (TREE_CODE (type) == POINTER_TYPE 124 && VOID_TYPE_P (TREE_TYPE (type)) 125 && TYPE_QUALS (TREE_TYPE (type)) == TYPE_UNQUALIFIED))); 126} 127/* This is a cache to hold if two types are compatible or not. */ 128 129struct tagged_tu_seen_cache { 130 const struct tagged_tu_seen_cache * next; 131 tree t1; 132 tree t2; 133 /* The return value of tagged_types_tu_compatible_p if we had seen 134 these two types already. */ 135 int val; 136}; 137 138static const struct tagged_tu_seen_cache * tagged_tu_seen_base; 139static void free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *); 140 141/* Do `exp = require_complete_type (exp);' to make sure exp 142 does not have an incomplete type. (That includes void types.) */ 143 144tree 145require_complete_type (tree value) 146{ 147 tree type = TREE_TYPE (value); 148 149 if (value == error_mark_node || type == error_mark_node) 150 return error_mark_node; 151 152 /* First, detect a valid value with a complete type. */ 153 if (COMPLETE_TYPE_P (type)) 154 return value; 155 156 c_incomplete_type_error (value, type); 157 return error_mark_node; 158} 159 160/* Print an error message for invalid use of an incomplete type. 161 VALUE is the expression that was used (or 0 if that isn't known) 162 and TYPE is the type that was invalid. */ 163 164void 165c_incomplete_type_error (tree value, tree type) 166{ 167 const char *type_code_string; 168 169 /* Avoid duplicate error message. */ 170 if (TREE_CODE (type) == ERROR_MARK) 171 return; 172 173 if (value != 0 && (TREE_CODE (value) == VAR_DECL 174 || TREE_CODE (value) == PARM_DECL)) 175 error ("%qD has an incomplete type", value); 176 else 177 { 178 retry: 179 /* We must print an error message. Be clever about what it says. */ 180 181 switch (TREE_CODE (type)) 182 { 183 case RECORD_TYPE: 184 type_code_string = "struct"; 185 break; 186 187 case UNION_TYPE: 188 type_code_string = "union"; 189 break; 190 191 case ENUMERAL_TYPE: 192 type_code_string = "enum"; 193 break; 194 195 case VOID_TYPE: 196 error ("invalid use of void expression"); 197 return; 198 199 case ARRAY_TYPE: 200 if (TYPE_DOMAIN (type)) 201 { 202 if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL) 203 { 204 error ("invalid use of flexible array member"); 205 return; 206 } 207 type = TREE_TYPE (type); 208 goto retry; 209 } 210 error ("invalid use of array with unspecified bounds"); 211 return; 212 213 default: 214 gcc_unreachable (); 215 } 216 217 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE) 218 error ("invalid use of undefined type %<%s %E%>", 219 type_code_string, TYPE_NAME (type)); 220 else 221 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */ 222 error ("invalid use of incomplete typedef %qD", TYPE_NAME (type)); 223 } 224} 225 226/* Given a type, apply default promotions wrt unnamed function 227 arguments and return the new type. */ 228 229tree 230c_type_promotes_to (tree type) 231{ 232 if (TYPE_MAIN_VARIANT (type) == float_type_node) 233 return double_type_node; 234 235 if (c_promoting_integer_type_p (type)) 236 { 237 /* Preserve unsignedness if not really getting any wider. */ 238 if (TYPE_UNSIGNED (type) 239 && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))) 240 return unsigned_type_node; 241 return integer_type_node; 242 } 243 244 return type; 245} 246 247/* Return a variant of TYPE which has all the type qualifiers of LIKE 248 as well as those of TYPE. */ 249 250static tree 251qualify_type (tree type, tree like) 252{ 253 return c_build_qualified_type (type, 254 TYPE_QUALS (type) | TYPE_QUALS (like)); 255} 256 257/* Return true iff the given tree T is a variable length array. */ 258 259bool 260c_vla_type_p (tree t) 261{ 262 if (TREE_CODE (t) == ARRAY_TYPE 263 && C_TYPE_VARIABLE_SIZE (t)) 264 return true; 265 return false; 266} 267 268/* Return the composite type of two compatible types. 269 270 We assume that comptypes has already been done and returned 271 nonzero; if that isn't so, this may crash. In particular, we 272 assume that qualifiers match. */ 273 274tree 275composite_type (tree t1, tree t2) 276{ 277 enum tree_code code1; 278 enum tree_code code2; 279 tree attributes; 280 281 /* Save time if the two types are the same. */ 282 283 if (t1 == t2) return t1; 284 285 /* If one type is nonsense, use the other. */ 286 if (t1 == error_mark_node) 287 return t2; 288 if (t2 == error_mark_node) 289 return t1; 290 291 code1 = TREE_CODE (t1); 292 code2 = TREE_CODE (t2); 293 294 /* Merge the attributes. */ 295 attributes = targetm.merge_type_attributes (t1, t2); 296 297 /* If one is an enumerated type and the other is the compatible 298 integer type, the composite type might be either of the two 299 (DR#013 question 3). For consistency, use the enumerated type as 300 the composite type. */ 301 302 if (code1 == ENUMERAL_TYPE && code2 == INTEGER_TYPE) 303 return t1; 304 if (code2 == ENUMERAL_TYPE && code1 == INTEGER_TYPE) 305 return t2; 306 307 gcc_assert (code1 == code2); 308 309 switch (code1) 310 { 311 case POINTER_TYPE: 312 /* For two pointers, do this recursively on the target type. */ 313 { 314 tree pointed_to_1 = TREE_TYPE (t1); 315 tree pointed_to_2 = TREE_TYPE (t2); 316 tree target = composite_type (pointed_to_1, pointed_to_2); 317 t1 = build_pointer_type (target); 318 t1 = build_type_attribute_variant (t1, attributes); 319 return qualify_type (t1, t2); 320 } 321 322 case ARRAY_TYPE: 323 { 324 tree elt = composite_type (TREE_TYPE (t1), TREE_TYPE (t2)); 325 int quals; 326 tree unqual_elt; 327 tree d1 = TYPE_DOMAIN (t1); 328 tree d2 = TYPE_DOMAIN (t2); 329 bool d1_variable, d2_variable; 330 bool d1_zero, d2_zero; 331 332 /* We should not have any type quals on arrays at all. */ 333 gcc_assert (!TYPE_QUALS (t1) && !TYPE_QUALS (t2)); 334 335 d1_zero = d1 == 0 || !TYPE_MAX_VALUE (d1); 336 d2_zero = d2 == 0 || !TYPE_MAX_VALUE (d2); 337 338 d1_variable = (!d1_zero 339 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST 340 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST)); 341 d2_variable = (!d2_zero 342 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST 343 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST)); 344 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1)); 345 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2)); 346 347 /* Save space: see if the result is identical to one of the args. */ 348 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1) 349 && (d2_variable || d2_zero || !d1_variable)) 350 return build_type_attribute_variant (t1, attributes); 351 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2) 352 && (d1_variable || d1_zero || !d2_variable)) 353 return build_type_attribute_variant (t2, attributes); 354 355 if (elt == TREE_TYPE (t1) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1)) 356 return build_type_attribute_variant (t1, attributes); 357 if (elt == TREE_TYPE (t2) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1)) 358 return build_type_attribute_variant (t2, attributes); 359 360 /* Merge the element types, and have a size if either arg has 361 one. We may have qualifiers on the element types. To set 362 up TYPE_MAIN_VARIANT correctly, we need to form the 363 composite of the unqualified types and add the qualifiers 364 back at the end. */ 365 quals = TYPE_QUALS (strip_array_types (elt)); 366 unqual_elt = c_build_qualified_type (elt, TYPE_UNQUALIFIED); 367 t1 = build_array_type (unqual_elt, 368 TYPE_DOMAIN ((TYPE_DOMAIN (t1) 369 && (d2_variable 370 || d2_zero 371 || !d1_variable)) 372 ? t1 373 : t2)); 374 t1 = c_build_qualified_type (t1, quals); 375 return build_type_attribute_variant (t1, attributes); 376 } 377 378 case ENUMERAL_TYPE: 379 case RECORD_TYPE: 380 case UNION_TYPE: 381 if (attributes != NULL) 382 { 383 /* Try harder not to create a new aggregate type. */ 384 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes)) 385 return t1; 386 if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes)) 387 return t2; 388 } 389 return build_type_attribute_variant (t1, attributes); 390 391 case FUNCTION_TYPE: 392 /* Function types: prefer the one that specified arg types. 393 If both do, merge the arg types. Also merge the return types. */ 394 { 395 tree valtype = composite_type (TREE_TYPE (t1), TREE_TYPE (t2)); 396 tree p1 = TYPE_ARG_TYPES (t1); 397 tree p2 = TYPE_ARG_TYPES (t2); 398 int len; 399 tree newargs, n; 400 int i; 401 402 /* Save space: see if the result is identical to one of the args. */ 403 if (valtype == TREE_TYPE (t1) && !TYPE_ARG_TYPES (t2)) 404 return build_type_attribute_variant (t1, attributes); 405 if (valtype == TREE_TYPE (t2) && !TYPE_ARG_TYPES (t1)) 406 return build_type_attribute_variant (t2, attributes); 407 408 /* Simple way if one arg fails to specify argument types. */ 409 if (TYPE_ARG_TYPES (t1) == 0) 410 { 411 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2)); 412 t1 = build_type_attribute_variant (t1, attributes); 413 return qualify_type (t1, t2); 414 } 415 if (TYPE_ARG_TYPES (t2) == 0) 416 { 417 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1)); 418 t1 = build_type_attribute_variant (t1, attributes); 419 return qualify_type (t1, t2); 420 } 421 422 /* If both args specify argument types, we must merge the two 423 lists, argument by argument. */ 424 /* Tell global_bindings_p to return false so that variable_size 425 doesn't die on VLAs in parameter types. */ 426 c_override_global_bindings_to_false = true; 427 428 len = list_length (p1); 429 newargs = 0; 430 431 for (i = 0; i < len; i++) 432 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs); 433 434 n = newargs; 435 436 for (; p1; 437 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n)) 438 { 439 /* A null type means arg type is not specified. 440 Take whatever the other function type has. */ 441 if (TREE_VALUE (p1) == 0) 442 { 443 TREE_VALUE (n) = TREE_VALUE (p2); 444 goto parm_done; 445 } 446 if (TREE_VALUE (p2) == 0) 447 { 448 TREE_VALUE (n) = TREE_VALUE (p1); 449 goto parm_done; 450 } 451 452 /* Given wait (union {union wait *u; int *i} *) 453 and wait (union wait *), 454 prefer union wait * as type of parm. */ 455 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE 456 && TREE_VALUE (p1) != TREE_VALUE (p2)) 457 { 458 tree memb; 459 tree mv2 = TREE_VALUE (p2); 460 if (mv2 && mv2 != error_mark_node 461 && TREE_CODE (mv2) != ARRAY_TYPE) 462 mv2 = TYPE_MAIN_VARIANT (mv2); 463 for (memb = TYPE_FIELDS (TREE_VALUE (p1)); 464 memb; memb = TREE_CHAIN (memb)) 465 { 466 tree mv3 = TREE_TYPE (memb); 467 if (mv3 && mv3 != error_mark_node 468 && TREE_CODE (mv3) != ARRAY_TYPE) 469 mv3 = TYPE_MAIN_VARIANT (mv3); 470 if (comptypes (mv3, mv2)) 471 { 472 TREE_VALUE (n) = composite_type (TREE_TYPE (memb), 473 TREE_VALUE (p2)); 474 if (pedantic) 475 pedwarn ("function types not truly compatible in ISO C"); 476 goto parm_done; 477 } 478 } 479 } 480 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE 481 && TREE_VALUE (p2) != TREE_VALUE (p1)) 482 { 483 tree memb; 484 tree mv1 = TREE_VALUE (p1); 485 if (mv1 && mv1 != error_mark_node 486 && TREE_CODE (mv1) != ARRAY_TYPE) 487 mv1 = TYPE_MAIN_VARIANT (mv1); 488 for (memb = TYPE_FIELDS (TREE_VALUE (p2)); 489 memb; memb = TREE_CHAIN (memb)) 490 { 491 tree mv3 = TREE_TYPE (memb); 492 if (mv3 && mv3 != error_mark_node 493 && TREE_CODE (mv3) != ARRAY_TYPE) 494 mv3 = TYPE_MAIN_VARIANT (mv3); 495 if (comptypes (mv3, mv1)) 496 { 497 TREE_VALUE (n) = composite_type (TREE_TYPE (memb), 498 TREE_VALUE (p1)); 499 if (pedantic) 500 pedwarn ("function types not truly compatible in ISO C"); 501 goto parm_done; 502 } 503 } 504 } 505 TREE_VALUE (n) = composite_type (TREE_VALUE (p1), TREE_VALUE (p2)); 506 parm_done: ; 507 } 508 509 c_override_global_bindings_to_false = false; 510 t1 = build_function_type (valtype, newargs); 511 t1 = qualify_type (t1, t2); 512 /* ... falls through ... */ 513 } 514 515 default: 516 return build_type_attribute_variant (t1, attributes); 517 } 518 519} 520 521/* Return the type of a conditional expression between pointers to 522 possibly differently qualified versions of compatible types. 523 524 We assume that comp_target_types has already been done and returned 525 nonzero; if that isn't so, this may crash. */ 526 527static tree 528common_pointer_type (tree t1, tree t2) 529{ 530 tree attributes; 531 tree pointed_to_1, mv1; 532 tree pointed_to_2, mv2; 533 tree target; 534 535 /* Save time if the two types are the same. */ 536 537 if (t1 == t2) return t1; 538 539 /* If one type is nonsense, use the other. */ 540 if (t1 == error_mark_node) 541 return t2; 542 if (t2 == error_mark_node) 543 return t1; 544 545 gcc_assert (TREE_CODE (t1) == POINTER_TYPE 546 && TREE_CODE (t2) == POINTER_TYPE); 547 548 /* Merge the attributes. */ 549 attributes = targetm.merge_type_attributes (t1, t2); 550 551 /* Find the composite type of the target types, and combine the 552 qualifiers of the two types' targets. Do not lose qualifiers on 553 array element types by taking the TYPE_MAIN_VARIANT. */ 554 mv1 = pointed_to_1 = TREE_TYPE (t1); 555 mv2 = pointed_to_2 = TREE_TYPE (t2); 556 if (TREE_CODE (mv1) != ARRAY_TYPE) 557 mv1 = TYPE_MAIN_VARIANT (pointed_to_1); 558 if (TREE_CODE (mv2) != ARRAY_TYPE) 559 mv2 = TYPE_MAIN_VARIANT (pointed_to_2); 560 target = composite_type (mv1, mv2); 561 t1 = build_pointer_type (c_build_qualified_type 562 (target, 563 TYPE_QUALS (pointed_to_1) | 564 TYPE_QUALS (pointed_to_2))); 565 return build_type_attribute_variant (t1, attributes); 566} 567 568/* Return the common type for two arithmetic types under the usual 569 arithmetic conversions. The default conversions have already been 570 applied, and enumerated types converted to their compatible integer 571 types. The resulting type is unqualified and has no attributes. 572 573 This is the type for the result of most arithmetic operations 574 if the operands have the given two types. */ 575 576static tree 577c_common_type (tree t1, tree t2) 578{ 579 enum tree_code code1; 580 enum tree_code code2; 581 582 /* If one type is nonsense, use the other. */ 583 if (t1 == error_mark_node) 584 return t2; 585 if (t2 == error_mark_node) 586 return t1; 587 588 if (TYPE_QUALS (t1) != TYPE_UNQUALIFIED) 589 t1 = TYPE_MAIN_VARIANT (t1); 590 591 if (TYPE_QUALS (t2) != TYPE_UNQUALIFIED) 592 t2 = TYPE_MAIN_VARIANT (t2); 593 594 if (TYPE_ATTRIBUTES (t1) != NULL_TREE) 595 t1 = build_type_attribute_variant (t1, NULL_TREE); 596 597 if (TYPE_ATTRIBUTES (t2) != NULL_TREE) 598 t2 = build_type_attribute_variant (t2, NULL_TREE); 599 600 /* Save time if the two types are the same. */ 601 602 if (t1 == t2) return t1; 603 604 code1 = TREE_CODE (t1); 605 code2 = TREE_CODE (t2); 606 607 gcc_assert (code1 == VECTOR_TYPE || code1 == COMPLEX_TYPE 608 || code1 == REAL_TYPE || code1 == INTEGER_TYPE); 609 gcc_assert (code2 == VECTOR_TYPE || code2 == COMPLEX_TYPE 610 || code2 == REAL_TYPE || code2 == INTEGER_TYPE); 611 612 /* When one operand is a decimal float type, the other operand cannot be 613 a generic float type or a complex type. We also disallow vector types 614 here. */ 615 if ((DECIMAL_FLOAT_TYPE_P (t1) || DECIMAL_FLOAT_TYPE_P (t2)) 616 && !(DECIMAL_FLOAT_TYPE_P (t1) && DECIMAL_FLOAT_TYPE_P (t2))) 617 { 618 if (code1 == VECTOR_TYPE || code2 == VECTOR_TYPE) 619 { 620 error ("can%'t mix operands of decimal float and vector types"); 621 return error_mark_node; 622 } 623 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE) 624 { 625 error ("can%'t mix operands of decimal float and complex types"); 626 return error_mark_node; 627 } 628 if (code1 == REAL_TYPE && code2 == REAL_TYPE) 629 { 630 error ("can%'t mix operands of decimal float and other float types"); 631 return error_mark_node; 632 } 633 } 634 635 /* If one type is a vector type, return that type. (How the usual 636 arithmetic conversions apply to the vector types extension is not 637 precisely specified.) */ 638 if (code1 == VECTOR_TYPE) 639 return t1; 640 641 if (code2 == VECTOR_TYPE) 642 return t2; 643 644 /* If one type is complex, form the common type of the non-complex 645 components, then make that complex. Use T1 or T2 if it is the 646 required type. */ 647 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE) 648 { 649 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1; 650 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2; 651 tree subtype = c_common_type (subtype1, subtype2); 652 653 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype) 654 return t1; 655 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype) 656 return t2; 657 else 658 return build_complex_type (subtype); 659 } 660 661 /* If only one is real, use it as the result. */ 662 663 if (code1 == REAL_TYPE && code2 != REAL_TYPE) 664 return t1; 665 666 if (code2 == REAL_TYPE && code1 != REAL_TYPE) 667 return t2; 668 669 /* If both are real and either are decimal floating point types, use 670 the decimal floating point type with the greater precision. */ 671 672 if (code1 == REAL_TYPE && code2 == REAL_TYPE) 673 { 674 if (TYPE_MAIN_VARIANT (t1) == dfloat128_type_node 675 || TYPE_MAIN_VARIANT (t2) == dfloat128_type_node) 676 return dfloat128_type_node; 677 else if (TYPE_MAIN_VARIANT (t1) == dfloat64_type_node 678 || TYPE_MAIN_VARIANT (t2) == dfloat64_type_node) 679 return dfloat64_type_node; 680 else if (TYPE_MAIN_VARIANT (t1) == dfloat32_type_node 681 || TYPE_MAIN_VARIANT (t2) == dfloat32_type_node) 682 return dfloat32_type_node; 683 } 684 685 /* Both real or both integers; use the one with greater precision. */ 686 687 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2)) 688 return t1; 689 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1)) 690 return t2; 691 692 /* Same precision. Prefer long longs to longs to ints when the 693 same precision, following the C99 rules on integer type rank 694 (which are equivalent to the C90 rules for C90 types). */ 695 696 if (TYPE_MAIN_VARIANT (t1) == long_long_unsigned_type_node 697 || TYPE_MAIN_VARIANT (t2) == long_long_unsigned_type_node) 698 return long_long_unsigned_type_node; 699 700 if (TYPE_MAIN_VARIANT (t1) == long_long_integer_type_node 701 || TYPE_MAIN_VARIANT (t2) == long_long_integer_type_node) 702 { 703 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2)) 704 return long_long_unsigned_type_node; 705 else 706 return long_long_integer_type_node; 707 } 708 709 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node 710 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node) 711 return long_unsigned_type_node; 712 713 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node 714 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node) 715 { 716 /* But preserve unsignedness from the other type, 717 since long cannot hold all the values of an unsigned int. */ 718 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2)) 719 return long_unsigned_type_node; 720 else 721 return long_integer_type_node; 722 } 723 724 /* Likewise, prefer long double to double even if same size. */ 725 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node 726 || TYPE_MAIN_VARIANT (t2) == long_double_type_node) 727 return long_double_type_node; 728 729 /* Otherwise prefer the unsigned one. */ 730 731 if (TYPE_UNSIGNED (t1)) 732 return t1; 733 else 734 return t2; 735} 736 737/* Wrapper around c_common_type that is used by c-common.c and other 738 front end optimizations that remove promotions. ENUMERAL_TYPEs 739 are allowed here and are converted to their compatible integer types. 740 BOOLEAN_TYPEs are allowed here and return either boolean_type_node or 741 preferably a non-Boolean type as the common type. */ 742tree 743common_type (tree t1, tree t2) 744{ 745 if (TREE_CODE (t1) == ENUMERAL_TYPE) 746 t1 = c_common_type_for_size (TYPE_PRECISION (t1), 1); 747 if (TREE_CODE (t2) == ENUMERAL_TYPE) 748 t2 = c_common_type_for_size (TYPE_PRECISION (t2), 1); 749 750 /* If both types are BOOLEAN_TYPE, then return boolean_type_node. */ 751 if (TREE_CODE (t1) == BOOLEAN_TYPE 752 && TREE_CODE (t2) == BOOLEAN_TYPE) 753 return boolean_type_node; 754 755 /* If either type is BOOLEAN_TYPE, then return the other. */ 756 if (TREE_CODE (t1) == BOOLEAN_TYPE) 757 return t2; 758 if (TREE_CODE (t2) == BOOLEAN_TYPE) 759 return t1; 760 761 return c_common_type (t1, t2); 762} 763 764/* Return 1 if TYPE1 and TYPE2 are compatible types for assignment 765 or various other operations. Return 2 if they are compatible 766 but a warning may be needed if you use them together. */ 767 768int 769comptypes (tree type1, tree type2) 770{ 771 const struct tagged_tu_seen_cache * tagged_tu_seen_base1 = tagged_tu_seen_base; 772 int val; 773 774 val = comptypes_internal (type1, type2); 775 free_all_tagged_tu_seen_up_to (tagged_tu_seen_base1); 776 777 return val; 778} 779 780/* Return 1 if TYPE1 and TYPE2 are compatible types for assignment 781 or various other operations. Return 2 if they are compatible 782 but a warning may be needed if you use them together. This 783 differs from comptypes, in that we don't free the seen types. */ 784 785static int 786comptypes_internal (tree type1, tree type2) 787{ 788 tree t1 = type1; 789 tree t2 = type2; 790 int attrval, val; 791 792 /* Suppress errors caused by previously reported errors. */ 793 794 if (t1 == t2 || !t1 || !t2 795 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK) 796 return 1; 797 798 /* If either type is the internal version of sizetype, return the 799 language version. */ 800 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1) 801 && TYPE_ORIG_SIZE_TYPE (t1)) 802 t1 = TYPE_ORIG_SIZE_TYPE (t1); 803 804 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2) 805 && TYPE_ORIG_SIZE_TYPE (t2)) 806 t2 = TYPE_ORIG_SIZE_TYPE (t2); 807 808 809 /* Enumerated types are compatible with integer types, but this is 810 not transitive: two enumerated types in the same translation unit 811 are compatible with each other only if they are the same type. */ 812 813 if (TREE_CODE (t1) == ENUMERAL_TYPE && TREE_CODE (t2) != ENUMERAL_TYPE) 814 t1 = c_common_type_for_size (TYPE_PRECISION (t1), TYPE_UNSIGNED (t1)); 815 else if (TREE_CODE (t2) == ENUMERAL_TYPE && TREE_CODE (t1) != ENUMERAL_TYPE) 816 t2 = c_common_type_for_size (TYPE_PRECISION (t2), TYPE_UNSIGNED (t2)); 817 818 if (t1 == t2) 819 return 1; 820 821 /* Different classes of types can't be compatible. */ 822 823 if (TREE_CODE (t1) != TREE_CODE (t2)) 824 return 0; 825 826 /* Qualifiers must match. C99 6.7.3p9 */ 827 828 if (TYPE_QUALS (t1) != TYPE_QUALS (t2)) 829 return 0; 830 831 /* Allow for two different type nodes which have essentially the same 832 definition. Note that we already checked for equality of the type 833 qualifiers (just above). */ 834 835 if (TREE_CODE (t1) != ARRAY_TYPE 836 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2)) 837 return 1; 838 839 /* 1 if no need for warning yet, 2 if warning cause has been seen. */ 840 if (!(attrval = targetm.comp_type_attributes (t1, t2))) 841 return 0; 842 843 /* 1 if no need for warning yet, 2 if warning cause has been seen. */ 844 val = 0; 845 846 switch (TREE_CODE (t1)) 847 { 848 case POINTER_TYPE: 849 /* Do not remove mode or aliasing information. */ 850 if (TYPE_MODE (t1) != TYPE_MODE (t2) 851 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2)) 852 break; 853 val = (TREE_TYPE (t1) == TREE_TYPE (t2) 854 ? 1 : comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2))); 855 break; 856 857 case FUNCTION_TYPE: 858 val = function_types_compatible_p (t1, t2); 859 break; 860 861 case ARRAY_TYPE: 862 { 863 tree d1 = TYPE_DOMAIN (t1); 864 tree d2 = TYPE_DOMAIN (t2); 865 bool d1_variable, d2_variable; 866 bool d1_zero, d2_zero; 867 val = 1; 868 869 /* Target types must match incl. qualifiers. */ 870 if (TREE_TYPE (t1) != TREE_TYPE (t2) 871 && 0 == (val = comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2)))) 872 return 0; 873 874 /* Sizes must match unless one is missing or variable. */ 875 if (d1 == 0 || d2 == 0 || d1 == d2) 876 break; 877 878 d1_zero = !TYPE_MAX_VALUE (d1); 879 d2_zero = !TYPE_MAX_VALUE (d2); 880 881 d1_variable = (!d1_zero 882 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST 883 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST)); 884 d2_variable = (!d2_zero 885 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST 886 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST)); 887 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1)); 888 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2)); 889 890 if (d1_variable || d2_variable) 891 break; 892 if (d1_zero && d2_zero) 893 break; 894 if (d1_zero || d2_zero 895 || !tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)) 896 || !tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2))) 897 val = 0; 898 899 break; 900 } 901 902 case ENUMERAL_TYPE: 903 case RECORD_TYPE: 904 case UNION_TYPE: 905 if (val != 1 && !same_translation_unit_p (t1, t2)) 906 { 907 tree a1 = TYPE_ATTRIBUTES (t1); 908 tree a2 = TYPE_ATTRIBUTES (t2); 909 910 if (! attribute_list_contained (a1, a2) 911 && ! attribute_list_contained (a2, a1)) 912 break; 913 914 if (attrval != 2) 915 return tagged_types_tu_compatible_p (t1, t2); 916 val = tagged_types_tu_compatible_p (t1, t2); 917 } 918 break; 919 920 case VECTOR_TYPE: 921 val = TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2) 922 && comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2)); 923 break; 924 925 default: 926 break; 927 } 928 return attrval == 2 && val == 1 ? 2 : val; 929} 930 931/* Return 1 if TTL and TTR are pointers to types that are equivalent, 932 ignoring their qualifiers. */ 933 934static int 935comp_target_types (tree ttl, tree ttr) 936{ 937 int val; 938 tree mvl, mvr; 939 940 /* Do not lose qualifiers on element types of array types that are 941 pointer targets by taking their TYPE_MAIN_VARIANT. */ 942 mvl = TREE_TYPE (ttl); 943 mvr = TREE_TYPE (ttr); 944 if (TREE_CODE (mvl) != ARRAY_TYPE) 945 mvl = TYPE_MAIN_VARIANT (mvl); 946 if (TREE_CODE (mvr) != ARRAY_TYPE) 947 mvr = TYPE_MAIN_VARIANT (mvr); 948 val = comptypes (mvl, mvr); 949 950 if (val == 2 && pedantic) 951 pedwarn ("types are not quite compatible"); 952 return val; 953} 954 955/* Subroutines of `comptypes'. */ 956 957/* Determine whether two trees derive from the same translation unit. 958 If the CONTEXT chain ends in a null, that tree's context is still 959 being parsed, so if two trees have context chains ending in null, 960 they're in the same translation unit. */ 961int 962same_translation_unit_p (tree t1, tree t2) 963{ 964 while (t1 && TREE_CODE (t1) != TRANSLATION_UNIT_DECL) 965 switch (TREE_CODE_CLASS (TREE_CODE (t1))) 966 { 967 case tcc_declaration: 968 t1 = DECL_CONTEXT (t1); break; 969 case tcc_type: 970 t1 = TYPE_CONTEXT (t1); break; 971 case tcc_exceptional: 972 t1 = BLOCK_SUPERCONTEXT (t1); break; /* assume block */ 973 default: gcc_unreachable (); 974 } 975 976 while (t2 && TREE_CODE (t2) != TRANSLATION_UNIT_DECL) 977 switch (TREE_CODE_CLASS (TREE_CODE (t2))) 978 { 979 case tcc_declaration: 980 t2 = DECL_CONTEXT (t2); break; 981 case tcc_type: 982 t2 = TYPE_CONTEXT (t2); break; 983 case tcc_exceptional: 984 t2 = BLOCK_SUPERCONTEXT (t2); break; /* assume block */ 985 default: gcc_unreachable (); 986 } 987 988 return t1 == t2; 989} 990 991/* Allocate the seen two types, assuming that they are compatible. */ 992 993static struct tagged_tu_seen_cache * 994alloc_tagged_tu_seen_cache (tree t1, tree t2) 995{ 996 struct tagged_tu_seen_cache *tu = XNEW (struct tagged_tu_seen_cache); 997 tu->next = tagged_tu_seen_base; 998 tu->t1 = t1; 999 tu->t2 = t2; 1000 1001 tagged_tu_seen_base = tu; 1002 1003 /* The C standard says that two structures in different translation 1004 units are compatible with each other only if the types of their 1005 fields are compatible (among other things). We assume that they 1006 are compatible until proven otherwise when building the cache. 1007 An example where this can occur is: 1008 struct a 1009 { 1010 struct a *next; 1011 }; 1012 If we are comparing this against a similar struct in another TU, 1013 and did not assume they were compatible, we end up with an infinite 1014 loop. */ 1015 tu->val = 1; 1016 return tu; 1017} 1018 1019/* Free the seen types until we get to TU_TIL. */ 1020 1021static void 1022free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *tu_til) 1023{ 1024 const struct tagged_tu_seen_cache *tu = tagged_tu_seen_base; 1025 while (tu != tu_til) 1026 { 1027 struct tagged_tu_seen_cache *tu1 = (struct tagged_tu_seen_cache*)tu; 1028 tu = tu1->next; 1029 free (tu1); 1030 } 1031 tagged_tu_seen_base = tu_til; 1032} 1033 1034/* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are 1035 compatible. If the two types are not the same (which has been 1036 checked earlier), this can only happen when multiple translation 1037 units are being compiled. See C99 6.2.7 paragraph 1 for the exact 1038 rules. */ 1039 1040static int 1041tagged_types_tu_compatible_p (tree t1, tree t2) 1042{ 1043 tree s1, s2; 1044 bool needs_warning = false; 1045 1046 /* We have to verify that the tags of the types are the same. This 1047 is harder than it looks because this may be a typedef, so we have 1048 to go look at the original type. It may even be a typedef of a 1049 typedef... 1050 In the case of compiler-created builtin structs the TYPE_DECL 1051 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */ 1052 while (TYPE_NAME (t1) 1053 && TREE_CODE (TYPE_NAME (t1)) == TYPE_DECL 1054 && DECL_ORIGINAL_TYPE (TYPE_NAME (t1))) 1055 t1 = DECL_ORIGINAL_TYPE (TYPE_NAME (t1)); 1056 1057 while (TYPE_NAME (t2) 1058 && TREE_CODE (TYPE_NAME (t2)) == TYPE_DECL 1059 && DECL_ORIGINAL_TYPE (TYPE_NAME (t2))) 1060 t2 = DECL_ORIGINAL_TYPE (TYPE_NAME (t2)); 1061 1062 /* C90 didn't have the requirement that the two tags be the same. */ 1063 if (flag_isoc99 && TYPE_NAME (t1) != TYPE_NAME (t2)) 1064 return 0; 1065 1066 /* C90 didn't say what happened if one or both of the types were 1067 incomplete; we choose to follow C99 rules here, which is that they 1068 are compatible. */ 1069 if (TYPE_SIZE (t1) == NULL 1070 || TYPE_SIZE (t2) == NULL) 1071 return 1; 1072 1073 { 1074 const struct tagged_tu_seen_cache * tts_i; 1075 for (tts_i = tagged_tu_seen_base; tts_i != NULL; tts_i = tts_i->next) 1076 if (tts_i->t1 == t1 && tts_i->t2 == t2) 1077 return tts_i->val; 1078 } 1079 1080 switch (TREE_CODE (t1)) 1081 { 1082 case ENUMERAL_TYPE: 1083 { 1084 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2); 1085 /* Speed up the case where the type values are in the same order. */ 1086 tree tv1 = TYPE_VALUES (t1); 1087 tree tv2 = TYPE_VALUES (t2); 1088 1089 if (tv1 == tv2) 1090 { 1091 return 1; 1092 } 1093 1094 for (;tv1 && tv2; tv1 = TREE_CHAIN (tv1), tv2 = TREE_CHAIN (tv2)) 1095 { 1096 if (TREE_PURPOSE (tv1) != TREE_PURPOSE (tv2)) 1097 break; 1098 if (simple_cst_equal (TREE_VALUE (tv1), TREE_VALUE (tv2)) != 1) 1099 { 1100 tu->val = 0; 1101 return 0; 1102 } 1103 } 1104 1105 if (tv1 == NULL_TREE && tv2 == NULL_TREE) 1106 { 1107 return 1; 1108 } 1109 if (tv1 == NULL_TREE || tv2 == NULL_TREE) 1110 { 1111 tu->val = 0; 1112 return 0; 1113 } 1114 1115 if (list_length (TYPE_VALUES (t1)) != list_length (TYPE_VALUES (t2))) 1116 { 1117 tu->val = 0; 1118 return 0; 1119 } 1120 1121 for (s1 = TYPE_VALUES (t1); s1; s1 = TREE_CHAIN (s1)) 1122 { 1123 s2 = purpose_member (TREE_PURPOSE (s1), TYPE_VALUES (t2)); 1124 if (s2 == NULL 1125 || simple_cst_equal (TREE_VALUE (s1), TREE_VALUE (s2)) != 1) 1126 { 1127 tu->val = 0; 1128 return 0; 1129 } 1130 } 1131 return 1; 1132 } 1133 1134 case UNION_TYPE: 1135 { 1136 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2); 1137 if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2))) 1138 { 1139 tu->val = 0; 1140 return 0; 1141 } 1142 1143 /* Speed up the common case where the fields are in the same order. */ 1144 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2); s1 && s2; 1145 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2)) 1146 { 1147 int result; 1148 1149 1150 if (DECL_NAME (s1) == NULL 1151 || DECL_NAME (s1) != DECL_NAME (s2)) 1152 break; 1153 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2)); 1154 if (result == 0) 1155 { 1156 tu->val = 0; 1157 return 0; 1158 } 1159 if (result == 2) 1160 needs_warning = true; 1161 1162 if (TREE_CODE (s1) == FIELD_DECL 1163 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1), 1164 DECL_FIELD_BIT_OFFSET (s2)) != 1) 1165 { 1166 tu->val = 0; 1167 return 0; 1168 } 1169 } 1170 if (!s1 && !s2) 1171 { 1172 tu->val = needs_warning ? 2 : 1; 1173 return tu->val; 1174 } 1175 1176 for (s1 = TYPE_FIELDS (t1); s1; s1 = TREE_CHAIN (s1)) 1177 { 1178 bool ok = false; 1179 1180 if (DECL_NAME (s1) != NULL) 1181 for (s2 = TYPE_FIELDS (t2); s2; s2 = TREE_CHAIN (s2)) 1182 if (DECL_NAME (s1) == DECL_NAME (s2)) 1183 { 1184 int result; 1185 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2)); 1186 if (result == 0) 1187 { 1188 tu->val = 0; 1189 return 0; 1190 } 1191 if (result == 2) 1192 needs_warning = true; 1193 1194 if (TREE_CODE (s1) == FIELD_DECL 1195 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1), 1196 DECL_FIELD_BIT_OFFSET (s2)) != 1) 1197 break; 1198 1199 ok = true; 1200 break; 1201 } 1202 if (!ok) 1203 { 1204 tu->val = 0; 1205 return 0; 1206 } 1207 } 1208 tu->val = needs_warning ? 2 : 10; 1209 return tu->val; 1210 } 1211 1212 case RECORD_TYPE: 1213 { 1214 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2); 1215 1216 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2); 1217 s1 && s2; 1218 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2)) 1219 { 1220 int result; 1221 if (TREE_CODE (s1) != TREE_CODE (s2) 1222 || DECL_NAME (s1) != DECL_NAME (s2)) 1223 break; 1224 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2)); 1225 if (result == 0) 1226 break; 1227 if (result == 2) 1228 needs_warning = true; 1229 1230 if (TREE_CODE (s1) == FIELD_DECL 1231 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1), 1232 DECL_FIELD_BIT_OFFSET (s2)) != 1) 1233 break; 1234 } 1235 if (s1 && s2) 1236 tu->val = 0; 1237 else 1238 tu->val = needs_warning ? 2 : 1; 1239 return tu->val; 1240 } 1241 1242 default: 1243 gcc_unreachable (); 1244 } 1245} 1246 1247/* Return 1 if two function types F1 and F2 are compatible. 1248 If either type specifies no argument types, 1249 the other must specify a fixed number of self-promoting arg types. 1250 Otherwise, if one type specifies only the number of arguments, 1251 the other must specify that number of self-promoting arg types. 1252 Otherwise, the argument types must match. */ 1253 1254static int 1255function_types_compatible_p (tree f1, tree f2) 1256{ 1257 tree args1, args2; 1258 /* 1 if no need for warning yet, 2 if warning cause has been seen. */ 1259 int val = 1; 1260 int val1; 1261 tree ret1, ret2; 1262 1263 ret1 = TREE_TYPE (f1); 1264 ret2 = TREE_TYPE (f2); 1265 1266 /* 'volatile' qualifiers on a function's return type used to mean 1267 the function is noreturn. */ 1268 if (TYPE_VOLATILE (ret1) != TYPE_VOLATILE (ret2)) 1269 pedwarn ("function return types not compatible due to %<volatile%>"); 1270 if (TYPE_VOLATILE (ret1)) 1271 ret1 = build_qualified_type (TYPE_MAIN_VARIANT (ret1), 1272 TYPE_QUALS (ret1) & ~TYPE_QUAL_VOLATILE); 1273 if (TYPE_VOLATILE (ret2)) 1274 ret2 = build_qualified_type (TYPE_MAIN_VARIANT (ret2), 1275 TYPE_QUALS (ret2) & ~TYPE_QUAL_VOLATILE); 1276 val = comptypes_internal (ret1, ret2); 1277 if (val == 0) 1278 return 0; 1279 1280 args1 = TYPE_ARG_TYPES (f1); 1281 args2 = TYPE_ARG_TYPES (f2); 1282 1283 /* An unspecified parmlist matches any specified parmlist 1284 whose argument types don't need default promotions. */ 1285 1286 if (args1 == 0) 1287 { 1288 if (!self_promoting_args_p (args2)) 1289 return 0; 1290 /* If one of these types comes from a non-prototype fn definition, 1291 compare that with the other type's arglist. 1292 If they don't match, ask for a warning (but no error). */ 1293 if (TYPE_ACTUAL_ARG_TYPES (f1) 1294 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1))) 1295 val = 2; 1296 return val; 1297 } 1298 if (args2 == 0) 1299 { 1300 if (!self_promoting_args_p (args1)) 1301 return 0; 1302 if (TYPE_ACTUAL_ARG_TYPES (f2) 1303 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2))) 1304 val = 2; 1305 return val; 1306 } 1307 1308 /* Both types have argument lists: compare them and propagate results. */ 1309 val1 = type_lists_compatible_p (args1, args2); 1310 return val1 != 1 ? val1 : val; 1311} 1312 1313/* Check two lists of types for compatibility, 1314 returning 0 for incompatible, 1 for compatible, 1315 or 2 for compatible with warning. */ 1316 1317static int 1318type_lists_compatible_p (tree args1, tree args2) 1319{ 1320 /* 1 if no need for warning yet, 2 if warning cause has been seen. */ 1321 int val = 1; 1322 int newval = 0; 1323 1324 while (1) 1325 { 1326 tree a1, mv1, a2, mv2; 1327 if (args1 == 0 && args2 == 0) 1328 return val; 1329 /* If one list is shorter than the other, 1330 they fail to match. */ 1331 if (args1 == 0 || args2 == 0) 1332 return 0; 1333 mv1 = a1 = TREE_VALUE (args1); 1334 mv2 = a2 = TREE_VALUE (args2); 1335 if (mv1 && mv1 != error_mark_node && TREE_CODE (mv1) != ARRAY_TYPE) 1336 mv1 = TYPE_MAIN_VARIANT (mv1); 1337 if (mv2 && mv2 != error_mark_node && TREE_CODE (mv2) != ARRAY_TYPE) 1338 mv2 = TYPE_MAIN_VARIANT (mv2); 1339 /* A null pointer instead of a type 1340 means there is supposed to be an argument 1341 but nothing is specified about what type it has. 1342 So match anything that self-promotes. */ 1343 if (a1 == 0) 1344 { 1345 if (c_type_promotes_to (a2) != a2) 1346 return 0; 1347 } 1348 else if (a2 == 0) 1349 { 1350 if (c_type_promotes_to (a1) != a1) 1351 return 0; 1352 } 1353 /* If one of the lists has an error marker, ignore this arg. */ 1354 else if (TREE_CODE (a1) == ERROR_MARK 1355 || TREE_CODE (a2) == ERROR_MARK) 1356 ; 1357 else if (!(newval = comptypes_internal (mv1, mv2))) 1358 { 1359 /* Allow wait (union {union wait *u; int *i} *) 1360 and wait (union wait *) to be compatible. */ 1361 if (TREE_CODE (a1) == UNION_TYPE 1362 && (TYPE_NAME (a1) == 0 1363 || TYPE_TRANSPARENT_UNION (a1)) 1364 && TREE_CODE (TYPE_SIZE (a1)) == INTEGER_CST 1365 && tree_int_cst_equal (TYPE_SIZE (a1), 1366 TYPE_SIZE (a2))) 1367 { 1368 tree memb; 1369 for (memb = TYPE_FIELDS (a1); 1370 memb; memb = TREE_CHAIN (memb)) 1371 { 1372 tree mv3 = TREE_TYPE (memb); 1373 if (mv3 && mv3 != error_mark_node 1374 && TREE_CODE (mv3) != ARRAY_TYPE) 1375 mv3 = TYPE_MAIN_VARIANT (mv3); 1376 if (comptypes_internal (mv3, mv2)) 1377 break; 1378 } 1379 if (memb == 0) 1380 return 0; 1381 } 1382 else if (TREE_CODE (a2) == UNION_TYPE 1383 && (TYPE_NAME (a2) == 0 1384 || TYPE_TRANSPARENT_UNION (a2)) 1385 && TREE_CODE (TYPE_SIZE (a2)) == INTEGER_CST 1386 && tree_int_cst_equal (TYPE_SIZE (a2), 1387 TYPE_SIZE (a1))) 1388 { 1389 tree memb; 1390 for (memb = TYPE_FIELDS (a2); 1391 memb; memb = TREE_CHAIN (memb)) 1392 { 1393 tree mv3 = TREE_TYPE (memb); 1394 if (mv3 && mv3 != error_mark_node 1395 && TREE_CODE (mv3) != ARRAY_TYPE) 1396 mv3 = TYPE_MAIN_VARIANT (mv3); 1397 if (comptypes_internal (mv3, mv1)) 1398 break; 1399 } 1400 if (memb == 0) 1401 return 0; 1402 } 1403 else 1404 return 0; 1405 } 1406 1407 /* comptypes said ok, but record if it said to warn. */ 1408 if (newval > val) 1409 val = newval; 1410 1411 args1 = TREE_CHAIN (args1); 1412 args2 = TREE_CHAIN (args2); 1413 } 1414} 1415 1416/* Compute the size to increment a pointer by. */ 1417 1418static tree 1419c_size_in_bytes (tree type) 1420{ 1421 enum tree_code code = TREE_CODE (type); 1422 1423 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK) 1424 return size_one_node; 1425 1426 if (!COMPLETE_OR_VOID_TYPE_P (type)) 1427 { 1428 error ("arithmetic on pointer to an incomplete type"); 1429 return size_one_node; 1430 } 1431 1432 /* Convert in case a char is more than one unit. */ 1433 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type), 1434 size_int (TYPE_PRECISION (char_type_node) 1435 / BITS_PER_UNIT)); 1436} 1437 1438/* Return either DECL or its known constant value (if it has one). */ 1439 1440tree 1441decl_constant_value (tree decl) 1442{ 1443 if (/* Don't change a variable array bound or initial value to a constant 1444 in a place where a variable is invalid. Note that DECL_INITIAL 1445 isn't valid for a PARM_DECL. */ 1446 current_function_decl != 0 1447 && TREE_CODE (decl) != PARM_DECL 1448 && !TREE_THIS_VOLATILE (decl) 1449 && TREE_READONLY (decl) 1450 && DECL_INITIAL (decl) != 0 1451 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK 1452 /* This is invalid if initial value is not constant. 1453 If it has either a function call, a memory reference, 1454 or a variable, then re-evaluating it could give different results. */ 1455 && TREE_CONSTANT (DECL_INITIAL (decl)) 1456 /* Check for cases where this is sub-optimal, even though valid. */ 1457 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR) 1458 return DECL_INITIAL (decl); 1459 return decl; 1460} 1461 1462/* Return either DECL or its known constant value (if it has one), but 1463 return DECL if pedantic or DECL has mode BLKmode. This is for 1464 bug-compatibility with the old behavior of decl_constant_value 1465 (before GCC 3.0); every use of this function is a bug and it should 1466 be removed before GCC 3.1. It is not appropriate to use pedantic 1467 in a way that affects optimization, and BLKmode is probably not the 1468 right test for avoiding misoptimizations either. */ 1469 1470static tree 1471decl_constant_value_for_broken_optimization (tree decl) 1472{ 1473 tree ret; 1474 1475 if (pedantic || DECL_MODE (decl) == BLKmode) 1476 return decl; 1477 1478 ret = decl_constant_value (decl); 1479 /* Avoid unwanted tree sharing between the initializer and current 1480 function's body where the tree can be modified e.g. by the 1481 gimplifier. */ 1482 if (ret != decl && TREE_STATIC (decl)) 1483 ret = unshare_expr (ret); 1484 return ret; 1485} 1486 1487/* Convert the array expression EXP to a pointer. */ 1488static tree 1489array_to_pointer_conversion (tree exp) 1490{ 1491 tree orig_exp = exp; 1492 tree type = TREE_TYPE (exp); 1493 tree adr; 1494 tree restype = TREE_TYPE (type); 1495 tree ptrtype; 1496 1497 gcc_assert (TREE_CODE (type) == ARRAY_TYPE); 1498 1499 STRIP_TYPE_NOPS (exp); 1500 1501 if (TREE_NO_WARNING (orig_exp)) 1502 TREE_NO_WARNING (exp) = 1; 1503 1504 ptrtype = build_pointer_type (restype); 1505 1506 if (TREE_CODE (exp) == INDIRECT_REF) 1507 return convert (ptrtype, TREE_OPERAND (exp, 0)); 1508 1509 if (TREE_CODE (exp) == VAR_DECL) 1510 { 1511 /* We are making an ADDR_EXPR of ptrtype. This is a valid 1512 ADDR_EXPR because it's the best way of representing what 1513 happens in C when we take the address of an array and place 1514 it in a pointer to the element type. */ 1515 adr = build1 (ADDR_EXPR, ptrtype, exp); 1516 if (!c_mark_addressable (exp)) 1517 return error_mark_node; 1518 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */ 1519 return adr; 1520 } 1521 1522 /* This way is better for a COMPONENT_REF since it can 1523 simplify the offset for a component. */ 1524 adr = build_unary_op (ADDR_EXPR, exp, 1); 1525 return convert (ptrtype, adr); 1526} 1527 1528/* Convert the function expression EXP to a pointer. */ 1529static tree 1530function_to_pointer_conversion (tree exp) 1531{ 1532 tree orig_exp = exp; 1533 1534 gcc_assert (TREE_CODE (TREE_TYPE (exp)) == FUNCTION_TYPE); 1535 1536 STRIP_TYPE_NOPS (exp); 1537 1538 if (TREE_NO_WARNING (orig_exp)) 1539 TREE_NO_WARNING (exp) = 1; 1540 1541 return build_unary_op (ADDR_EXPR, exp, 0); 1542} 1543 1544/* Perform the default conversion of arrays and functions to pointers. 1545 Return the result of converting EXP. For any other expression, just 1546 return EXP after removing NOPs. */ 1547 1548struct c_expr 1549default_function_array_conversion (struct c_expr exp) 1550{ 1551 tree orig_exp = exp.value; 1552 tree type = TREE_TYPE (exp.value); 1553 enum tree_code code = TREE_CODE (type); 1554 1555 switch (code) 1556 { 1557 case ARRAY_TYPE: 1558 { 1559 bool not_lvalue = false; 1560 bool lvalue_array_p; 1561 1562 while ((TREE_CODE (exp.value) == NON_LVALUE_EXPR 1563 || TREE_CODE (exp.value) == NOP_EXPR 1564 || TREE_CODE (exp.value) == CONVERT_EXPR) 1565 && TREE_TYPE (TREE_OPERAND (exp.value, 0)) == type) 1566 { 1567 if (TREE_CODE (exp.value) == NON_LVALUE_EXPR) 1568 not_lvalue = true; 1569 exp.value = TREE_OPERAND (exp.value, 0); 1570 } 1571 1572 if (TREE_NO_WARNING (orig_exp)) 1573 TREE_NO_WARNING (exp.value) = 1; 1574 1575 lvalue_array_p = !not_lvalue && lvalue_p (exp.value); 1576 if (!flag_isoc99 && !lvalue_array_p) 1577 { 1578 /* Before C99, non-lvalue arrays do not decay to pointers. 1579 Normally, using such an array would be invalid; but it can 1580 be used correctly inside sizeof or as a statement expression. 1581 Thus, do not give an error here; an error will result later. */ 1582 return exp; 1583 } 1584 1585 exp.value = array_to_pointer_conversion (exp.value); 1586 } 1587 break; 1588 case FUNCTION_TYPE: 1589 exp.value = function_to_pointer_conversion (exp.value); 1590 break; 1591 default: 1592 STRIP_TYPE_NOPS (exp.value); 1593 if (TREE_NO_WARNING (orig_exp)) 1594 TREE_NO_WARNING (exp.value) = 1; 1595 break; 1596 } 1597 1598 return exp; 1599} 1600 1601 1602/* EXP is an expression of integer type. Apply the integer promotions 1603 to it and return the promoted value. */ 1604 1605tree 1606perform_integral_promotions (tree exp) 1607{ 1608 tree type = TREE_TYPE (exp); 1609 enum tree_code code = TREE_CODE (type); 1610 1611 gcc_assert (INTEGRAL_TYPE_P (type)); 1612 1613 /* Normally convert enums to int, 1614 but convert wide enums to something wider. */ 1615 if (code == ENUMERAL_TYPE) 1616 { 1617 type = c_common_type_for_size (MAX (TYPE_PRECISION (type), 1618 TYPE_PRECISION (integer_type_node)), 1619 ((TYPE_PRECISION (type) 1620 >= TYPE_PRECISION (integer_type_node)) 1621 && TYPE_UNSIGNED (type))); 1622 1623 return convert (type, exp); 1624 } 1625 1626 /* ??? This should no longer be needed now bit-fields have their 1627 proper types. */ 1628 if (TREE_CODE (exp) == COMPONENT_REF 1629 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1)) 1630 /* If it's thinner than an int, promote it like a 1631 c_promoting_integer_type_p, otherwise leave it alone. */ 1632 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)), 1633 TYPE_PRECISION (integer_type_node))) 1634 return convert (integer_type_node, exp); 1635 1636 if (c_promoting_integer_type_p (type)) 1637 { 1638 /* Preserve unsignedness if not really getting any wider. */ 1639 if (TYPE_UNSIGNED (type) 1640 && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)) 1641 return convert (unsigned_type_node, exp); 1642 1643 return convert (integer_type_node, exp); 1644 } 1645 1646 return exp; 1647} 1648 1649 1650/* Perform default promotions for C data used in expressions. 1651 Enumeral types or short or char are converted to int. 1652 In addition, manifest constants symbols are replaced by their values. */ 1653 1654tree 1655default_conversion (tree exp) 1656{ 1657 tree orig_exp; 1658 tree type = TREE_TYPE (exp); 1659 enum tree_code code = TREE_CODE (type); 1660 1661 /* Functions and arrays have been converted during parsing. */ 1662 gcc_assert (code != FUNCTION_TYPE); 1663 if (code == ARRAY_TYPE) 1664 return exp; 1665 1666 /* Constants can be used directly unless they're not loadable. */ 1667 if (TREE_CODE (exp) == CONST_DECL) 1668 exp = DECL_INITIAL (exp); 1669 1670 /* Replace a nonvolatile const static variable with its value unless 1671 it is an array, in which case we must be sure that taking the 1672 address of the array produces consistent results. */ 1673 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE) 1674 { 1675 exp = decl_constant_value_for_broken_optimization (exp); 1676 type = TREE_TYPE (exp); 1677 } 1678 1679 /* Strip no-op conversions. */ 1680 orig_exp = exp; 1681 STRIP_TYPE_NOPS (exp); 1682 1683 if (TREE_NO_WARNING (orig_exp)) 1684 TREE_NO_WARNING (exp) = 1; 1685 1686 if (INTEGRAL_TYPE_P (type)) 1687 return perform_integral_promotions (exp); 1688 1689 if (code == VOID_TYPE) 1690 { 1691 error ("void value not ignored as it ought to be"); 1692 return error_mark_node; 1693 } 1694 return exp; 1695} 1696 1697/* Look up COMPONENT in a structure or union DECL. 1698 1699 If the component name is not found, returns NULL_TREE. Otherwise, 1700 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL 1701 stepping down the chain to the component, which is in the last 1702 TREE_VALUE of the list. Normally the list is of length one, but if 1703 the component is embedded within (nested) anonymous structures or 1704 unions, the list steps down the chain to the component. */ 1705 1706static tree 1707lookup_field (tree decl, tree component) 1708{ 1709 tree type = TREE_TYPE (decl); 1710 tree field; 1711 1712 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers 1713 to the field elements. Use a binary search on this array to quickly 1714 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC 1715 will always be set for structures which have many elements. */ 1716 1717 if (TYPE_LANG_SPECIFIC (type) && TYPE_LANG_SPECIFIC (type)->s) 1718 { 1719 int bot, top, half; 1720 tree *field_array = &TYPE_LANG_SPECIFIC (type)->s->elts[0]; 1721 1722 field = TYPE_FIELDS (type); 1723 bot = 0; 1724 top = TYPE_LANG_SPECIFIC (type)->s->len; 1725 while (top - bot > 1) 1726 { 1727 half = (top - bot + 1) >> 1; 1728 field = field_array[bot+half]; 1729 1730 if (DECL_NAME (field) == NULL_TREE) 1731 { 1732 /* Step through all anon unions in linear fashion. */ 1733 while (DECL_NAME (field_array[bot]) == NULL_TREE) 1734 { 1735 field = field_array[bot++]; 1736 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE 1737 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE) 1738 { 1739 tree anon = lookup_field (field, component); 1740 1741 if (anon) 1742 return tree_cons (NULL_TREE, field, anon); 1743 } 1744 } 1745 1746 /* Entire record is only anon unions. */ 1747 if (bot > top) 1748 return NULL_TREE; 1749 1750 /* Restart the binary search, with new lower bound. */ 1751 continue; 1752 } 1753 1754 if (DECL_NAME (field) == component) 1755 break; 1756 if (DECL_NAME (field) < component) 1757 bot += half; 1758 else 1759 top = bot + half; 1760 } 1761 1762 if (DECL_NAME (field_array[bot]) == component) 1763 field = field_array[bot]; 1764 else if (DECL_NAME (field) != component) 1765 return NULL_TREE; 1766 } 1767 else 1768 { 1769 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) 1770 { 1771 if (DECL_NAME (field) == NULL_TREE 1772 && (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE 1773 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)) 1774 { 1775 tree anon = lookup_field (field, component); 1776 1777 if (anon) 1778 return tree_cons (NULL_TREE, field, anon); 1779 } 1780 1781 if (DECL_NAME (field) == component) 1782 break; 1783 } 1784 1785 if (field == NULL_TREE) 1786 return NULL_TREE; 1787 } 1788 1789 return tree_cons (NULL_TREE, field, NULL_TREE); 1790} 1791 1792/* Make an expression to refer to the COMPONENT field of 1793 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */ 1794 1795tree 1796build_component_ref (tree datum, tree component) 1797{ 1798 tree type = TREE_TYPE (datum); 1799 enum tree_code code = TREE_CODE (type); 1800 tree field = NULL; 1801 tree ref; 1802 1803 if (!objc_is_public (datum, component)) 1804 return error_mark_node; 1805 1806 /* See if there is a field or component with name COMPONENT. */ 1807 1808 if (code == RECORD_TYPE || code == UNION_TYPE) 1809 { 1810 if (!COMPLETE_TYPE_P (type)) 1811 { 1812 c_incomplete_type_error (NULL_TREE, type); 1813 return error_mark_node; 1814 } 1815 1816 field = lookup_field (datum, component); 1817 1818 if (!field) 1819 { 1820 error ("%qT has no member named %qE", type, component); 1821 return error_mark_node; 1822 } 1823 1824 /* Chain the COMPONENT_REFs if necessary down to the FIELD. 1825 This might be better solved in future the way the C++ front 1826 end does it - by giving the anonymous entities each a 1827 separate name and type, and then have build_component_ref 1828 recursively call itself. We can't do that here. */ 1829 do 1830 { 1831 tree subdatum = TREE_VALUE (field); 1832 int quals; 1833 tree subtype; 1834 1835 if (TREE_TYPE (subdatum) == error_mark_node) 1836 return error_mark_node; 1837 1838 quals = TYPE_QUALS (strip_array_types (TREE_TYPE (subdatum))); 1839 quals |= TYPE_QUALS (TREE_TYPE (datum)); 1840 subtype = c_build_qualified_type (TREE_TYPE (subdatum), quals); 1841 1842 ref = build3 (COMPONENT_REF, subtype, datum, subdatum, 1843 NULL_TREE); 1844 if (TREE_READONLY (datum) || TREE_READONLY (subdatum)) 1845 TREE_READONLY (ref) = 1; 1846 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (subdatum)) 1847 TREE_THIS_VOLATILE (ref) = 1; 1848 1849 if (TREE_DEPRECATED (subdatum)) 1850 warn_deprecated_use (subdatum); 1851 1852 /* APPLE LOCAL begin "unavailable" attribute (radar 2809697) */ 1853 if (TREE_UNAVAILABLE (subdatum)) 1854 error_unavailable_use (subdatum); 1855 /* APPLE LOCAL end "unavailable" attribute (radar 2809697) */ 1856 1857 datum = ref; 1858 1859 field = TREE_CHAIN (field); 1860 } 1861 while (field); 1862 1863 return ref; 1864 } 1865 else if (code != ERROR_MARK) 1866 error ("request for member %qE in something not a structure or union", 1867 component); 1868 1869 return error_mark_node; 1870} 1871 1872/* Given an expression PTR for a pointer, return an expression 1873 for the value pointed to. 1874 ERRORSTRING is the name of the operator to appear in error messages. */ 1875 1876tree 1877build_indirect_ref (tree ptr, const char *errorstring) 1878{ 1879 tree pointer = default_conversion (ptr); 1880 tree type = TREE_TYPE (pointer); 1881 1882 if (TREE_CODE (type) == POINTER_TYPE) 1883 { 1884 if (TREE_CODE (pointer) == CONVERT_EXPR 1885 || TREE_CODE (pointer) == NOP_EXPR 1886 || TREE_CODE (pointer) == VIEW_CONVERT_EXPR) 1887 { 1888 /* If a warning is issued, mark it to avoid duplicates from 1889 the backend. This only needs to be done at 1890 warn_strict_aliasing > 2. */ 1891 if (warn_strict_aliasing > 2) 1892 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (pointer, 0)), 1893 type, TREE_OPERAND (pointer, 0))) 1894 TREE_NO_WARNING (pointer) = 1; 1895 } 1896 1897 if (TREE_CODE (pointer) == ADDR_EXPR 1898 && (TREE_TYPE (TREE_OPERAND (pointer, 0)) 1899 == TREE_TYPE (type))) 1900 return TREE_OPERAND (pointer, 0); 1901 else 1902 { 1903 tree t = TREE_TYPE (type); 1904 tree ref; 1905 1906 ref = build1 (INDIRECT_REF, t, pointer); 1907 1908 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE) 1909 { 1910 error ("dereferencing pointer to incomplete type"); 1911 return error_mark_node; 1912 } 1913 if (VOID_TYPE_P (t) && skip_evaluation == 0) 1914 warning (0, "dereferencing %<void *%> pointer"); 1915 1916 /* We *must* set TREE_READONLY when dereferencing a pointer to const, 1917 so that we get the proper error message if the result is used 1918 to assign to. Also, &* is supposed to be a no-op. 1919 And ANSI C seems to specify that the type of the result 1920 should be the const type. */ 1921 /* A de-reference of a pointer to const is not a const. It is valid 1922 to change it via some other pointer. */ 1923 TREE_READONLY (ref) = TYPE_READONLY (t); 1924 TREE_SIDE_EFFECTS (ref) 1925 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer); 1926 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t); 1927 return ref; 1928 } 1929 } 1930 else if (TREE_CODE (pointer) != ERROR_MARK) 1931 error ("invalid type argument of %qs (have %qT)", errorstring, type); 1932 return error_mark_node; 1933} 1934 1935/* This handles expressions of the form "a[i]", which denotes 1936 an array reference. 1937 1938 This is logically equivalent in C to *(a+i), but we may do it differently. 1939 If A is a variable or a member, we generate a primitive ARRAY_REF. 1940 This avoids forcing the array out of registers, and can work on 1941 arrays that are not lvalues (for example, members of structures returned 1942 by functions). */ 1943 1944tree 1945build_array_ref (tree array, tree index) 1946{ 1947 bool swapped = false; 1948 if (TREE_TYPE (array) == error_mark_node 1949 || TREE_TYPE (index) == error_mark_node) 1950 return error_mark_node; 1951 1952 if (TREE_CODE (TREE_TYPE (array)) != ARRAY_TYPE 1953 && TREE_CODE (TREE_TYPE (array)) != POINTER_TYPE) 1954 { 1955 tree temp; 1956 if (TREE_CODE (TREE_TYPE (index)) != ARRAY_TYPE 1957 && TREE_CODE (TREE_TYPE (index)) != POINTER_TYPE) 1958 { 1959 error ("subscripted value is neither array nor pointer"); 1960 return error_mark_node; 1961 } 1962 temp = array; 1963 array = index; 1964 index = temp; 1965 swapped = true; 1966 } 1967 1968 if (!INTEGRAL_TYPE_P (TREE_TYPE (index))) 1969 { 1970 error ("array subscript is not an integer"); 1971 return error_mark_node; 1972 } 1973 1974 if (TREE_CODE (TREE_TYPE (TREE_TYPE (array))) == FUNCTION_TYPE) 1975 { 1976 error ("subscripted value is pointer to function"); 1977 return error_mark_node; 1978 } 1979 1980 /* ??? Existing practice has been to warn only when the char 1981 index is syntactically the index, not for char[array]. */ 1982 if (!swapped) 1983 warn_array_subscript_with_type_char (index); 1984 1985 /* Apply default promotions *after* noticing character types. */ 1986 index = default_conversion (index); 1987 1988 gcc_assert (TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE); 1989 1990 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE) 1991 { 1992 tree rval, type; 1993 1994 /* An array that is indexed by a non-constant 1995 cannot be stored in a register; we must be able to do 1996 address arithmetic on its address. 1997 Likewise an array of elements of variable size. */ 1998 if (TREE_CODE (index) != INTEGER_CST 1999 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array))) 2000 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST)) 2001 { 2002 if (!c_mark_addressable (array)) 2003 return error_mark_node; 2004 } 2005 /* An array that is indexed by a constant value which is not within 2006 the array bounds cannot be stored in a register either; because we 2007 would get a crash in store_bit_field/extract_bit_field when trying 2008 to access a non-existent part of the register. */ 2009 if (TREE_CODE (index) == INTEGER_CST 2010 && TYPE_DOMAIN (TREE_TYPE (array)) 2011 && !int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array)))) 2012 { 2013 if (!c_mark_addressable (array)) 2014 return error_mark_node; 2015 } 2016 2017 if (pedantic) 2018 { 2019 tree foo = array; 2020 while (TREE_CODE (foo) == COMPONENT_REF) 2021 foo = TREE_OPERAND (foo, 0); 2022 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo)) 2023 pedwarn ("ISO C forbids subscripting %<register%> array"); 2024 else if (!flag_isoc99 && !lvalue_p (foo)) 2025 pedwarn ("ISO C90 forbids subscripting non-lvalue array"); 2026 } 2027 2028 type = TREE_TYPE (TREE_TYPE (array)); 2029 if (TREE_CODE (type) != ARRAY_TYPE) 2030 type = TYPE_MAIN_VARIANT (type); 2031 rval = build4 (ARRAY_REF, type, array, index, NULL_TREE, NULL_TREE); 2032 /* Array ref is const/volatile if the array elements are 2033 or if the array is. */ 2034 TREE_READONLY (rval) 2035 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array))) 2036 | TREE_READONLY (array)); 2037 TREE_SIDE_EFFECTS (rval) 2038 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array))) 2039 | TREE_SIDE_EFFECTS (array)); 2040 TREE_THIS_VOLATILE (rval) 2041 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array))) 2042 /* This was added by rms on 16 Nov 91. 2043 It fixes vol struct foo *a; a->elts[1] 2044 in an inline function. 2045 Hope it doesn't break something else. */ 2046 | TREE_THIS_VOLATILE (array)); 2047 return require_complete_type (fold (rval)); 2048 } 2049 else 2050 { 2051 tree ar = default_conversion (array); 2052 2053 if (ar == error_mark_node) 2054 return ar; 2055 2056 gcc_assert (TREE_CODE (TREE_TYPE (ar)) == POINTER_TYPE); 2057 gcc_assert (TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) != FUNCTION_TYPE); 2058 2059 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, index, 0), 2060 "array indexing"); 2061 } 2062} 2063 2064/* Build an external reference to identifier ID. FUN indicates 2065 whether this will be used for a function call. LOC is the source 2066 location of the identifier. */ 2067tree 2068build_external_ref (tree id, int fun, location_t loc) 2069{ 2070 tree ref; 2071 tree decl = lookup_name (id); 2072 2073 /* In Objective-C, an instance variable (ivar) may be preferred to 2074 whatever lookup_name() found. */ 2075 decl = objc_lookup_ivar (decl, id); 2076 2077 if (decl && decl != error_mark_node) 2078 ref = decl; 2079 else if (fun) 2080 /* Implicit function declaration. */ 2081 ref = implicitly_declare (id); 2082 else if (decl == error_mark_node) 2083 /* Don't complain about something that's already been 2084 complained about. */ 2085 return error_mark_node; 2086 else 2087 { 2088 undeclared_variable (id, loc); 2089 return error_mark_node; 2090 } 2091 2092 if (TREE_TYPE (ref) == error_mark_node) 2093 return error_mark_node; 2094 2095 if (TREE_DEPRECATED (ref)) 2096 warn_deprecated_use (ref); 2097 2098 /* APPLE LOCAL begin "unavailable" attribute (radar 2809697) */ 2099 if (TREE_UNAVAILABLE (ref)) 2100 error_unavailable_use (ref); 2101 /* APPLE LOCAL end "unavailable" attribute (radar 2809697) */ 2102 2103 if (!skip_evaluation) 2104 assemble_external (ref); 2105 TREE_USED (ref) = 1; 2106 2107 if (TREE_CODE (ref) == FUNCTION_DECL && !in_alignof) 2108 { 2109 if (!in_sizeof && !in_typeof) 2110 C_DECL_USED (ref) = 1; 2111 else if (DECL_INITIAL (ref) == 0 2112 && DECL_EXTERNAL (ref) 2113 && !TREE_PUBLIC (ref)) 2114 record_maybe_used_decl (ref); 2115 } 2116 2117 if (TREE_CODE (ref) == CONST_DECL) 2118 { 2119 used_types_insert (TREE_TYPE (ref)); 2120 ref = DECL_INITIAL (ref); 2121 TREE_CONSTANT (ref) = 1; 2122 TREE_INVARIANT (ref) = 1; 2123 } 2124 else if (current_function_decl != 0 2125 && !DECL_FILE_SCOPE_P (current_function_decl) 2126 && (TREE_CODE (ref) == VAR_DECL 2127 || TREE_CODE (ref) == PARM_DECL 2128 || TREE_CODE (ref) == FUNCTION_DECL)) 2129 { 2130 tree context = decl_function_context (ref); 2131 2132 if (context != 0 && context != current_function_decl) 2133 DECL_NONLOCAL (ref) = 1; 2134 } 2135 /* C99 6.7.4p3: An inline definition of a function with external 2136 linkage ... shall not contain a reference to an identifier with 2137 internal linkage. */ 2138 else if (current_function_decl != 0 2139 && DECL_DECLARED_INLINE_P (current_function_decl) 2140 && DECL_EXTERNAL (current_function_decl) 2141 && VAR_OR_FUNCTION_DECL_P (ref) 2142 && DECL_FILE_SCOPE_P (ref) 2143 && pedantic 2144 && (TREE_CODE (ref) != VAR_DECL || TREE_STATIC (ref)) 2145 && ! TREE_PUBLIC (ref)) 2146 pedwarn ("%H%qD is static but used in inline function %qD " 2147 "which is not static", &loc, ref, current_function_decl); 2148 2149 return ref; 2150} 2151 2152/* Record details of decls possibly used inside sizeof or typeof. */ 2153struct maybe_used_decl 2154{ 2155 /* The decl. */ 2156 tree decl; 2157 /* The level seen at (in_sizeof + in_typeof). */ 2158 int level; 2159 /* The next one at this level or above, or NULL. */ 2160 struct maybe_used_decl *next; 2161}; 2162 2163static struct maybe_used_decl *maybe_used_decls; 2164 2165/* Record that DECL, an undefined static function reference seen 2166 inside sizeof or typeof, might be used if the operand of sizeof is 2167 a VLA type or the operand of typeof is a variably modified 2168 type. */ 2169 2170static void 2171record_maybe_used_decl (tree decl) 2172{ 2173 struct maybe_used_decl *t = XOBNEW (&parser_obstack, struct maybe_used_decl); 2174 t->decl = decl; 2175 t->level = in_sizeof + in_typeof; 2176 t->next = maybe_used_decls; 2177 maybe_used_decls = t; 2178} 2179 2180/* Pop the stack of decls possibly used inside sizeof or typeof. If 2181 USED is false, just discard them. If it is true, mark them used 2182 (if no longer inside sizeof or typeof) or move them to the next 2183 level up (if still inside sizeof or typeof). */ 2184 2185void 2186pop_maybe_used (bool used) 2187{ 2188 struct maybe_used_decl *p = maybe_used_decls; 2189 int cur_level = in_sizeof + in_typeof; 2190 while (p && p->level > cur_level) 2191 { 2192 if (used) 2193 { 2194 if (cur_level == 0) 2195 C_DECL_USED (p->decl) = 1; 2196 else 2197 p->level = cur_level; 2198 } 2199 p = p->next; 2200 } 2201 if (!used || cur_level == 0) 2202 maybe_used_decls = p; 2203} 2204 2205/* Return the result of sizeof applied to EXPR. */ 2206 2207struct c_expr 2208c_expr_sizeof_expr (struct c_expr expr) 2209{ 2210 struct c_expr ret; 2211 if (expr.value == error_mark_node) 2212 { 2213 ret.value = error_mark_node; 2214 ret.original_code = ERROR_MARK; 2215 pop_maybe_used (false); 2216 } 2217 else 2218 { 2219 ret.value = c_sizeof (TREE_TYPE (expr.value)); 2220 ret.original_code = ERROR_MARK; 2221 if (c_vla_type_p (TREE_TYPE (expr.value))) 2222 { 2223 /* sizeof is evaluated when given a vla (C99 6.5.3.4p2). */ 2224 ret.value = build2 (COMPOUND_EXPR, TREE_TYPE (ret.value), expr.value, ret.value); 2225 } 2226 pop_maybe_used (C_TYPE_VARIABLE_SIZE (TREE_TYPE (expr.value))); 2227 } 2228 return ret; 2229} 2230 2231/* Return the result of sizeof applied to T, a structure for the type 2232 name passed to sizeof (rather than the type itself). */ 2233 2234struct c_expr 2235c_expr_sizeof_type (struct c_type_name *t) 2236{ 2237 tree type; 2238 struct c_expr ret; 2239 type = groktypename (t); 2240 ret.value = c_sizeof (type); 2241 ret.original_code = ERROR_MARK; 2242 pop_maybe_used (type != error_mark_node 2243 ? C_TYPE_VARIABLE_SIZE (type) : false); 2244 return ret; 2245} 2246 2247/* Build a function call to function FUNCTION with parameters PARAMS. 2248 PARAMS is a list--a chain of TREE_LIST nodes--in which the 2249 TREE_VALUE of each node is a parameter-expression. 2250 FUNCTION's data type may be a function type or a pointer-to-function. */ 2251 2252tree 2253build_function_call (tree function, tree params) 2254{ 2255 tree fntype, fundecl = 0; 2256 tree coerced_params; 2257 tree name = NULL_TREE, result; 2258 tree tem; 2259 2260 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */ 2261 STRIP_TYPE_NOPS (function); 2262 2263 /* Convert anything with function type to a pointer-to-function. */ 2264 if (TREE_CODE (function) == FUNCTION_DECL) 2265 { 2266 /* Implement type-directed function overloading for builtins. 2267 resolve_overloaded_builtin and targetm.resolve_overloaded_builtin 2268 handle all the type checking. The result is a complete expression 2269 that implements this function call. */ 2270 tem = resolve_overloaded_builtin (function, params); 2271 if (tem) 2272 return tem; 2273 2274 name = DECL_NAME (function); 2275 fundecl = function; 2276 } 2277 if (TREE_CODE (TREE_TYPE (function)) == FUNCTION_TYPE) 2278 function = function_to_pointer_conversion (function); 2279 2280 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF 2281 expressions, like those used for ObjC messenger dispatches. */ 2282 function = objc_rewrite_function_call (function, params); 2283 2284 fntype = TREE_TYPE (function); 2285 2286 if (TREE_CODE (fntype) == ERROR_MARK) 2287 return error_mark_node; 2288 2289 if (!(TREE_CODE (fntype) == POINTER_TYPE 2290 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)) 2291 { 2292 error ("called object %qE is not a function", function); 2293 return error_mark_node; 2294 } 2295 2296 if (fundecl && TREE_THIS_VOLATILE (fundecl)) 2297 current_function_returns_abnormally = 1; 2298 2299 /* fntype now gets the type of function pointed to. */ 2300 fntype = TREE_TYPE (fntype); 2301 2302 /* Check that the function is called through a compatible prototype. 2303 If it is not, replace the call by a trap, wrapped up in a compound 2304 expression if necessary. This has the nice side-effect to prevent 2305 the tree-inliner from generating invalid assignment trees which may 2306 blow up in the RTL expander later. */ 2307 if ((TREE_CODE (function) == NOP_EXPR 2308 || TREE_CODE (function) == CONVERT_EXPR) 2309 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR 2310 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL 2311 && !comptypes (fntype, TREE_TYPE (tem))) 2312 { 2313 tree return_type = TREE_TYPE (fntype); 2314 tree trap = build_function_call (built_in_decls[BUILT_IN_TRAP], 2315 NULL_TREE); 2316 2317 /* This situation leads to run-time undefined behavior. We can't, 2318 therefore, simply error unless we can prove that all possible 2319 executions of the program must execute the code. */ 2320 warning (0, "function called through a non-compatible type"); 2321 2322 /* We can, however, treat "undefined" any way we please. 2323 Call abort to encourage the user to fix the program. */ 2324 inform ("if this code is reached, the program will abort"); 2325 2326 if (VOID_TYPE_P (return_type)) 2327 return trap; 2328 else 2329 { 2330 tree rhs; 2331 2332 if (AGGREGATE_TYPE_P (return_type)) 2333 rhs = build_compound_literal (return_type, 2334 build_constructor (return_type, 0)); 2335 else 2336 rhs = fold_convert (return_type, integer_zero_node); 2337 2338 return build2 (COMPOUND_EXPR, return_type, trap, rhs); 2339 } 2340 } 2341 2342 /* Convert the parameters to the types declared in the 2343 function prototype, or apply default promotions. */ 2344 2345 coerced_params 2346 = convert_arguments (TYPE_ARG_TYPES (fntype), params, function, fundecl); 2347 2348 if (coerced_params == error_mark_node) 2349 return error_mark_node; 2350 2351 /* Check that the arguments to the function are valid. */ 2352 2353 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params, 2354 TYPE_ARG_TYPES (fntype)); 2355 2356 if (require_constant_value) 2357 { 2358 result = fold_build3_initializer (CALL_EXPR, TREE_TYPE (fntype), 2359 function, coerced_params, NULL_TREE); 2360 2361 if (TREE_CONSTANT (result) 2362 && (name == NULL_TREE 2363 || strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10) != 0)) 2364 pedwarn_init ("initializer element is not constant"); 2365 } 2366 else 2367 result = fold_build3 (CALL_EXPR, TREE_TYPE (fntype), 2368 function, coerced_params, NULL_TREE); 2369 2370 if (VOID_TYPE_P (TREE_TYPE (result))) 2371 return result; 2372 return require_complete_type (result); 2373} 2374 2375/* Convert the argument expressions in the list VALUES 2376 to the types in the list TYPELIST. The result is a list of converted 2377 argument expressions, unless there are too few arguments in which 2378 case it is error_mark_node. 2379 2380 If TYPELIST is exhausted, or when an element has NULL as its type, 2381 perform the default conversions. 2382 2383 PARMLIST is the chain of parm decls for the function being called. 2384 It may be 0, if that info is not available. 2385 It is used only for generating error messages. 2386 2387 FUNCTION is a tree for the called function. It is used only for 2388 error messages, where it is formatted with %qE. 2389 2390 This is also where warnings about wrong number of args are generated. 2391 2392 Both VALUES and the returned value are chains of TREE_LIST nodes 2393 with the elements of the list in the TREE_VALUE slots of those nodes. */ 2394 2395static tree 2396convert_arguments (tree typelist, tree values, tree function, tree fundecl) 2397{ 2398 tree typetail, valtail; 2399 tree result = NULL; 2400 int parmnum; 2401 tree selector; 2402 2403 /* Change pointer to function to the function itself for 2404 diagnostics. */ 2405 if (TREE_CODE (function) == ADDR_EXPR 2406 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL) 2407 function = TREE_OPERAND (function, 0); 2408 2409 /* Handle an ObjC selector specially for diagnostics. */ 2410 selector = objc_message_selector (); 2411 2412 /* Scan the given expressions and types, producing individual 2413 converted arguments and pushing them on RESULT in reverse order. */ 2414 2415 for (valtail = values, typetail = typelist, parmnum = 0; 2416 valtail; 2417 valtail = TREE_CHAIN (valtail), parmnum++) 2418 { 2419 tree type = typetail ? TREE_VALUE (typetail) : 0; 2420 tree val = TREE_VALUE (valtail); 2421 tree rname = function; 2422 int argnum = parmnum + 1; 2423 const char *invalid_func_diag; 2424 2425 if (type == void_type_node) 2426 { 2427 error ("too many arguments to function %qE", function); 2428 break; 2429 } 2430 2431 if (selector && argnum > 2) 2432 { 2433 rname = selector; 2434 argnum -= 2; 2435 } 2436 2437 STRIP_TYPE_NOPS (val); 2438 2439 val = require_complete_type (val); 2440 2441 if (type != 0) 2442 { 2443 /* Formal parm type is specified by a function prototype. */ 2444 tree parmval; 2445 2446 if (type == error_mark_node || !COMPLETE_TYPE_P (type)) 2447 { 2448 error ("type of formal parameter %d is incomplete", parmnum + 1); 2449 parmval = val; 2450 } 2451 else 2452 { 2453 /* Optionally warn about conversions that 2454 differ from the default conversions. */ 2455 if (warn_conversion || warn_traditional) 2456 { 2457 unsigned int formal_prec = TYPE_PRECISION (type); 2458 2459 if (INTEGRAL_TYPE_P (type) 2460 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) 2461 warning (0, "passing argument %d of %qE as integer " 2462 "rather than floating due to prototype", 2463 argnum, rname); 2464 if (INTEGRAL_TYPE_P (type) 2465 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE) 2466 warning (0, "passing argument %d of %qE as integer " 2467 "rather than complex due to prototype", 2468 argnum, rname); 2469 else if (TREE_CODE (type) == COMPLEX_TYPE 2470 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) 2471 warning (0, "passing argument %d of %qE as complex " 2472 "rather than floating due to prototype", 2473 argnum, rname); 2474 else if (TREE_CODE (type) == REAL_TYPE 2475 && INTEGRAL_TYPE_P (TREE_TYPE (val))) 2476 warning (0, "passing argument %d of %qE as floating " 2477 "rather than integer due to prototype", 2478 argnum, rname); 2479 else if (TREE_CODE (type) == COMPLEX_TYPE 2480 && INTEGRAL_TYPE_P (TREE_TYPE (val))) 2481 warning (0, "passing argument %d of %qE as complex " 2482 "rather than integer due to prototype", 2483 argnum, rname); 2484 else if (TREE_CODE (type) == REAL_TYPE 2485 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE) 2486 warning (0, "passing argument %d of %qE as floating " 2487 "rather than complex due to prototype", 2488 argnum, rname); 2489 /* ??? At some point, messages should be written about 2490 conversions between complex types, but that's too messy 2491 to do now. */ 2492 else if (TREE_CODE (type) == REAL_TYPE 2493 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE) 2494 { 2495 /* Warn if any argument is passed as `float', 2496 since without a prototype it would be `double'. */ 2497 if (formal_prec == TYPE_PRECISION (float_type_node) 2498 && type != dfloat32_type_node) 2499 warning (0, "passing argument %d of %qE as %<float%> " 2500 "rather than %<double%> due to prototype", 2501 argnum, rname); 2502 2503 /* Warn if mismatch between argument and prototype 2504 for decimal float types. Warn of conversions with 2505 binary float types and of precision narrowing due to 2506 prototype. */ 2507 else if (type != TREE_TYPE (val) 2508 && (type == dfloat32_type_node 2509 || type == dfloat64_type_node 2510 || type == dfloat128_type_node 2511 || TREE_TYPE (val) == dfloat32_type_node 2512 || TREE_TYPE (val) == dfloat64_type_node 2513 || TREE_TYPE (val) == dfloat128_type_node) 2514 && (formal_prec 2515 <= TYPE_PRECISION (TREE_TYPE (val)) 2516 || (type == dfloat128_type_node 2517 && (TREE_TYPE (val) 2518 != dfloat64_type_node 2519 && (TREE_TYPE (val) 2520 != dfloat32_type_node))) 2521 || (type == dfloat64_type_node 2522 && (TREE_TYPE (val) 2523 != dfloat32_type_node)))) 2524 warning (0, "passing argument %d of %qE as %qT " 2525 "rather than %qT due to prototype", 2526 argnum, rname, type, TREE_TYPE (val)); 2527 2528 } 2529 /* Detect integer changing in width or signedness. 2530 These warnings are only activated with 2531 -Wconversion, not with -Wtraditional. */ 2532 else if (warn_conversion && INTEGRAL_TYPE_P (type) 2533 && INTEGRAL_TYPE_P (TREE_TYPE (val))) 2534 { 2535 tree would_have_been = default_conversion (val); 2536 tree type1 = TREE_TYPE (would_have_been); 2537 2538 if (TREE_CODE (type) == ENUMERAL_TYPE 2539 && (TYPE_MAIN_VARIANT (type) 2540 == TYPE_MAIN_VARIANT (TREE_TYPE (val)))) 2541 /* No warning if function asks for enum 2542 and the actual arg is that enum type. */ 2543 ; 2544 else if (formal_prec != TYPE_PRECISION (type1)) 2545 warning (OPT_Wconversion, "passing argument %d of %qE " 2546 "with different width due to prototype", 2547 argnum, rname); 2548 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1)) 2549 ; 2550 /* Don't complain if the formal parameter type 2551 is an enum, because we can't tell now whether 2552 the value was an enum--even the same enum. */ 2553 else if (TREE_CODE (type) == ENUMERAL_TYPE) 2554 ; 2555 else if (TREE_CODE (val) == INTEGER_CST 2556 && int_fits_type_p (val, type)) 2557 /* Change in signedness doesn't matter 2558 if a constant value is unaffected. */ 2559 ; 2560 /* If the value is extended from a narrower 2561 unsigned type, it doesn't matter whether we 2562 pass it as signed or unsigned; the value 2563 certainly is the same either way. */ 2564 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type) 2565 && TYPE_UNSIGNED (TREE_TYPE (val))) 2566 ; 2567 else if (TYPE_UNSIGNED (type)) 2568 warning (OPT_Wconversion, "passing argument %d of %qE " 2569 "as unsigned due to prototype", 2570 argnum, rname); 2571 else 2572 warning (OPT_Wconversion, "passing argument %d of %qE " 2573 "as signed due to prototype", argnum, rname); 2574 } 2575 } 2576 2577 parmval = convert_for_assignment (type, val, ic_argpass, 2578 fundecl, function, 2579 parmnum + 1); 2580 2581 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0) 2582 && INTEGRAL_TYPE_P (type) 2583 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))) 2584 parmval = default_conversion (parmval); 2585 } 2586 result = tree_cons (NULL_TREE, parmval, result); 2587 } 2588 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE 2589 && (TYPE_PRECISION (TREE_TYPE (val)) 2590 < TYPE_PRECISION (double_type_node)) 2591 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (val)))) 2592 /* Convert `float' to `double'. */ 2593 result = tree_cons (NULL_TREE, convert (double_type_node, val), result); 2594 else if ((invalid_func_diag = 2595 targetm.calls.invalid_arg_for_unprototyped_fn (typelist, fundecl, val))) 2596 { 2597 error (invalid_func_diag, ""); 2598 return error_mark_node; 2599 } 2600 else 2601 /* Convert `short' and `char' to full-size `int'. */ 2602 result = tree_cons (NULL_TREE, default_conversion (val), result); 2603 2604 if (typetail) 2605 typetail = TREE_CHAIN (typetail); 2606 } 2607 2608 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node) 2609 { 2610 error ("too few arguments to function %qE", function); 2611 return error_mark_node; 2612 } 2613 2614 return nreverse (result); 2615} 2616 2617/* This is the entry point used by the parser to build unary operators 2618 in the input. CODE, a tree_code, specifies the unary operator, and 2619 ARG is the operand. For unary plus, the C parser currently uses 2620 CONVERT_EXPR for code. */ 2621 2622struct c_expr 2623parser_build_unary_op (enum tree_code code, struct c_expr arg) 2624{ 2625 struct c_expr result; 2626 2627 result.original_code = ERROR_MARK; 2628 result.value = build_unary_op (code, arg.value, 0); 2629 2630 if (TREE_OVERFLOW_P (result.value) && !TREE_OVERFLOW_P (arg.value)) 2631 overflow_warning (result.value); 2632 2633 return result; 2634} 2635 2636/* This is the entry point used by the parser to build binary operators 2637 in the input. CODE, a tree_code, specifies the binary operator, and 2638 ARG1 and ARG2 are the operands. In addition to constructing the 2639 expression, we check for operands that were written with other binary 2640 operators in a way that is likely to confuse the user. */ 2641 2642struct c_expr 2643parser_build_binary_op (enum tree_code code, struct c_expr arg1, 2644 struct c_expr arg2) 2645{ 2646 struct c_expr result; 2647 2648 enum tree_code code1 = arg1.original_code; 2649 enum tree_code code2 = arg2.original_code; 2650 2651 result.value = build_binary_op (code, arg1.value, arg2.value, 1); 2652 result.original_code = code; 2653 2654 if (TREE_CODE (result.value) == ERROR_MARK) 2655 return result; 2656 2657 /* Check for cases such as x+y<<z which users are likely 2658 to misinterpret. */ 2659 if (warn_parentheses) 2660 warn_about_parentheses (code, code1, code2); 2661 2662 /* Warn about comparisons against string literals, with the exception 2663 of testing for equality or inequality of a string literal with NULL. */ 2664 if (code == EQ_EXPR || code == NE_EXPR) 2665 { 2666 if ((code1 == STRING_CST && !integer_zerop (arg2.value)) 2667 || (code2 == STRING_CST && !integer_zerop (arg1.value))) 2668 warning (OPT_Waddress, 2669 "comparison with string literal results in unspecified behaviour"); 2670 } 2671 else if (TREE_CODE_CLASS (code) == tcc_comparison 2672 && (code1 == STRING_CST || code2 == STRING_CST)) 2673 warning (OPT_Waddress, 2674 "comparison with string literal results in unspecified behaviour"); 2675 2676 if (TREE_OVERFLOW_P (result.value) 2677 && !TREE_OVERFLOW_P (arg1.value) 2678 && !TREE_OVERFLOW_P (arg2.value)) 2679 overflow_warning (result.value); 2680 2681 return result; 2682} 2683 2684/* Return a tree for the difference of pointers OP0 and OP1. 2685 The resulting tree has type int. */ 2686 2687static tree 2688pointer_diff (tree op0, tree op1) 2689{ 2690 tree restype = ptrdiff_type_node; 2691 2692 tree target_type = TREE_TYPE (TREE_TYPE (op0)); 2693 tree con0, con1, lit0, lit1; 2694 tree orig_op1 = op1; 2695 2696 if (pedantic || warn_pointer_arith) 2697 { 2698 if (TREE_CODE (target_type) == VOID_TYPE) 2699 pedwarn ("pointer of type %<void *%> used in subtraction"); 2700 if (TREE_CODE (target_type) == FUNCTION_TYPE) 2701 pedwarn ("pointer to a function used in subtraction"); 2702 } 2703 2704 /* If the conversion to ptrdiff_type does anything like widening or 2705 converting a partial to an integral mode, we get a convert_expression 2706 that is in the way to do any simplifications. 2707 (fold-const.c doesn't know that the extra bits won't be needed. 2708 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a 2709 different mode in place.) 2710 So first try to find a common term here 'by hand'; we want to cover 2711 at least the cases that occur in legal static initializers. */ 2712 if ((TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == CONVERT_EXPR) 2713 && (TYPE_PRECISION (TREE_TYPE (op0)) 2714 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0))))) 2715 con0 = TREE_OPERAND (op0, 0); 2716 else 2717 con0 = op0; 2718 if ((TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == CONVERT_EXPR) 2719 && (TYPE_PRECISION (TREE_TYPE (op1)) 2720 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0))))) 2721 con1 = TREE_OPERAND (op1, 0); 2722 else 2723 con1 = op1; 2724 2725 if (TREE_CODE (con0) == PLUS_EXPR) 2726 { 2727 lit0 = TREE_OPERAND (con0, 1); 2728 con0 = TREE_OPERAND (con0, 0); 2729 } 2730 else 2731 lit0 = integer_zero_node; 2732 2733 if (TREE_CODE (con1) == PLUS_EXPR) 2734 { 2735 lit1 = TREE_OPERAND (con1, 1); 2736 con1 = TREE_OPERAND (con1, 0); 2737 } 2738 else 2739 lit1 = integer_zero_node; 2740 2741 if (operand_equal_p (con0, con1, 0)) 2742 { 2743 op0 = lit0; 2744 op1 = lit1; 2745 } 2746 2747 2748 /* First do the subtraction as integers; 2749 then drop through to build the divide operator. 2750 Do not do default conversions on the minus operator 2751 in case restype is a short type. */ 2752 2753 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0), 2754 convert (restype, op1), 0); 2755 /* This generates an error if op1 is pointer to incomplete type. */ 2756 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1)))) 2757 error ("arithmetic on pointer to an incomplete type"); 2758 2759 /* This generates an error if op0 is pointer to incomplete type. */ 2760 op1 = c_size_in_bytes (target_type); 2761 2762 /* Divide by the size, in easiest possible way. */ 2763 return fold_build2 (EXACT_DIV_EXPR, restype, op0, convert (restype, op1)); 2764} 2765 2766/* Construct and perhaps optimize a tree representation 2767 for a unary operation. CODE, a tree_code, specifies the operation 2768 and XARG is the operand. 2769 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses 2770 the default promotions (such as from short to int). 2771 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero 2772 allows non-lvalues; this is only used to handle conversion of non-lvalue 2773 arrays to pointers in C99. */ 2774 2775tree 2776build_unary_op (enum tree_code code, tree xarg, int flag) 2777{ 2778 /* No default_conversion here. It causes trouble for ADDR_EXPR. */ 2779 tree arg = xarg; 2780 tree argtype = 0; 2781 enum tree_code typecode = TREE_CODE (TREE_TYPE (arg)); 2782 tree val; 2783 int noconvert = flag; 2784 const char *invalid_op_diag; 2785 2786 if (typecode == ERROR_MARK) 2787 return error_mark_node; 2788 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE) 2789 typecode = INTEGER_TYPE; 2790 2791 if ((invalid_op_diag 2792 = targetm.invalid_unary_op (code, TREE_TYPE (xarg)))) 2793 { 2794 error (invalid_op_diag, ""); 2795 return error_mark_node; 2796 } 2797 2798 switch (code) 2799 { 2800 case CONVERT_EXPR: 2801 /* This is used for unary plus, because a CONVERT_EXPR 2802 is enough to prevent anybody from looking inside for 2803 associativity, but won't generate any code. */ 2804 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE 2805 || typecode == COMPLEX_TYPE 2806 || typecode == VECTOR_TYPE)) 2807 { 2808 error ("wrong type argument to unary plus"); 2809 return error_mark_node; 2810 } 2811 else if (!noconvert) 2812 arg = default_conversion (arg); 2813 arg = non_lvalue (arg); 2814 break; 2815 2816 case NEGATE_EXPR: 2817 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE 2818 || typecode == COMPLEX_TYPE 2819 || typecode == VECTOR_TYPE)) 2820 { 2821 error ("wrong type argument to unary minus"); 2822 return error_mark_node; 2823 } 2824 else if (!noconvert) 2825 arg = default_conversion (arg); 2826 break; 2827 2828 case BIT_NOT_EXPR: 2829 if (typecode == INTEGER_TYPE || typecode == VECTOR_TYPE) 2830 { 2831 if (!noconvert) 2832 arg = default_conversion (arg); 2833 } 2834 else if (typecode == COMPLEX_TYPE) 2835 { 2836 code = CONJ_EXPR; 2837 if (pedantic) 2838 pedwarn ("ISO C does not support %<~%> for complex conjugation"); 2839 if (!noconvert) 2840 arg = default_conversion (arg); 2841 } 2842 else 2843 { 2844 error ("wrong type argument to bit-complement"); 2845 return error_mark_node; 2846 } 2847 break; 2848 2849 case ABS_EXPR: 2850 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE)) 2851 { 2852 error ("wrong type argument to abs"); 2853 return error_mark_node; 2854 } 2855 else if (!noconvert) 2856 arg = default_conversion (arg); 2857 break; 2858 2859 case CONJ_EXPR: 2860 /* Conjugating a real value is a no-op, but allow it anyway. */ 2861 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE 2862 || typecode == COMPLEX_TYPE)) 2863 { 2864 error ("wrong type argument to conjugation"); 2865 return error_mark_node; 2866 } 2867 else if (!noconvert) 2868 arg = default_conversion (arg); 2869 break; 2870 2871 case TRUTH_NOT_EXPR: 2872 if (typecode != INTEGER_TYPE 2873 && typecode != REAL_TYPE && typecode != POINTER_TYPE 2874 && typecode != COMPLEX_TYPE) 2875 { 2876 error ("wrong type argument to unary exclamation mark"); 2877 return error_mark_node; 2878 } 2879 arg = c_objc_common_truthvalue_conversion (arg); 2880 return invert_truthvalue (arg); 2881 2882 case REALPART_EXPR: 2883 if (TREE_CODE (arg) == COMPLEX_CST) 2884 return TREE_REALPART (arg); 2885 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE) 2886 return fold_build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg); 2887 else 2888 return arg; 2889 2890 case IMAGPART_EXPR: 2891 if (TREE_CODE (arg) == COMPLEX_CST) 2892 return TREE_IMAGPART (arg); 2893 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE) 2894 return fold_build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg); 2895 else 2896 return convert (TREE_TYPE (arg), integer_zero_node); 2897 2898 case PREINCREMENT_EXPR: 2899 case POSTINCREMENT_EXPR: 2900 case PREDECREMENT_EXPR: 2901 case POSTDECREMENT_EXPR: 2902 2903 /* Increment or decrement the real part of the value, 2904 and don't change the imaginary part. */ 2905 if (typecode == COMPLEX_TYPE) 2906 { 2907 tree real, imag; 2908 2909 if (pedantic) 2910 pedwarn ("ISO C does not support %<++%> and %<--%>" 2911 " on complex types"); 2912 2913 arg = stabilize_reference (arg); 2914 real = build_unary_op (REALPART_EXPR, arg, 1); 2915 imag = build_unary_op (IMAGPART_EXPR, arg, 1); 2916 return build2 (COMPLEX_EXPR, TREE_TYPE (arg), 2917 build_unary_op (code, real, 1), imag); 2918 } 2919 2920 /* Report invalid types. */ 2921 2922 if (typecode != POINTER_TYPE 2923 && typecode != INTEGER_TYPE && typecode != REAL_TYPE) 2924 { 2925 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) 2926 error ("wrong type argument to increment"); 2927 else 2928 error ("wrong type argument to decrement"); 2929 2930 return error_mark_node; 2931 } 2932 2933 { 2934 tree inc; 2935 tree result_type = TREE_TYPE (arg); 2936 2937 arg = get_unwidened (arg, 0); 2938 argtype = TREE_TYPE (arg); 2939 2940 /* Compute the increment. */ 2941 2942 if (typecode == POINTER_TYPE) 2943 { 2944 /* If pointer target is an undefined struct, 2945 we just cannot know how to do the arithmetic. */ 2946 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type))) 2947 { 2948 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) 2949 error ("increment of pointer to unknown structure"); 2950 else 2951 error ("decrement of pointer to unknown structure"); 2952 } 2953 else if ((pedantic || warn_pointer_arith) 2954 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE 2955 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)) 2956 { 2957 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) 2958 pedwarn ("wrong type argument to increment"); 2959 else 2960 pedwarn ("wrong type argument to decrement"); 2961 } 2962 2963 inc = c_size_in_bytes (TREE_TYPE (result_type)); 2964 } 2965 else 2966 inc = integer_one_node; 2967 2968 inc = convert (argtype, inc); 2969 2970 /* Complain about anything else that is not a true lvalue. */ 2971 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR 2972 || code == POSTINCREMENT_EXPR) 2973 ? lv_increment 2974 : lv_decrement))) 2975 return error_mark_node; 2976 2977 /* Report a read-only lvalue. */ 2978 if (TREE_READONLY (arg)) 2979 { 2980 readonly_error (arg, 2981 ((code == PREINCREMENT_EXPR 2982 || code == POSTINCREMENT_EXPR) 2983 ? lv_increment : lv_decrement)); 2984 return error_mark_node; 2985 } 2986 2987 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE) 2988 val = boolean_increment (code, arg); 2989 else 2990 val = build2 (code, TREE_TYPE (arg), arg, inc); 2991 TREE_SIDE_EFFECTS (val) = 1; 2992 val = convert (result_type, val); 2993 if (TREE_CODE (val) != code) 2994 TREE_NO_WARNING (val) = 1; 2995 return val; 2996 } 2997 2998 case ADDR_EXPR: 2999 /* Note that this operation never does default_conversion. */ 3000 3001 /* Let &* cancel out to simplify resulting code. */ 3002 if (TREE_CODE (arg) == INDIRECT_REF) 3003 { 3004 /* Don't let this be an lvalue. */ 3005 if (lvalue_p (TREE_OPERAND (arg, 0))) 3006 return non_lvalue (TREE_OPERAND (arg, 0)); 3007 return TREE_OPERAND (arg, 0); 3008 } 3009 3010 /* For &x[y], return x+y */ 3011 if (TREE_CODE (arg) == ARRAY_REF) 3012 { 3013 tree op0 = TREE_OPERAND (arg, 0); 3014 if (!c_mark_addressable (op0)) 3015 return error_mark_node; 3016 return build_binary_op (PLUS_EXPR, 3017 (TREE_CODE (TREE_TYPE (op0)) == ARRAY_TYPE 3018 ? array_to_pointer_conversion (op0) 3019 : op0), 3020 TREE_OPERAND (arg, 1), 1); 3021 } 3022 3023 /* Anything not already handled and not a true memory reference 3024 or a non-lvalue array is an error. */ 3025 else if (typecode != FUNCTION_TYPE && !flag 3026 && !lvalue_or_else (arg, lv_addressof)) 3027 return error_mark_node; 3028 3029 /* Ordinary case; arg is a COMPONENT_REF or a decl. */ 3030 argtype = TREE_TYPE (arg); 3031 3032 /* If the lvalue is const or volatile, merge that into the type 3033 to which the address will point. Note that you can't get a 3034 restricted pointer by taking the address of something, so we 3035 only have to deal with `const' and `volatile' here. */ 3036 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg)) 3037 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg))) 3038 argtype = c_build_type_variant (argtype, 3039 TREE_READONLY (arg), 3040 TREE_THIS_VOLATILE (arg)); 3041 3042 if (!c_mark_addressable (arg)) 3043 return error_mark_node; 3044 3045 gcc_assert (TREE_CODE (arg) != COMPONENT_REF 3046 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1))); 3047 3048 argtype = build_pointer_type (argtype); 3049 3050 /* ??? Cope with user tricks that amount to offsetof. Delete this 3051 when we have proper support for integer constant expressions. */ 3052 val = get_base_address (arg); 3053 if (val && TREE_CODE (val) == INDIRECT_REF 3054 && TREE_CONSTANT (TREE_OPERAND (val, 0))) 3055 { 3056 tree op0 = fold_convert (argtype, fold_offsetof (arg, val)), op1; 3057 3058 op1 = fold_convert (argtype, TREE_OPERAND (val, 0)); 3059 return fold_build2 (PLUS_EXPR, argtype, op0, op1); 3060 } 3061 3062 val = build1 (ADDR_EXPR, argtype, arg); 3063 3064 return val; 3065 3066 default: 3067 gcc_unreachable (); 3068 } 3069 3070 if (argtype == 0) 3071 argtype = TREE_TYPE (arg); 3072 return require_constant_value ? fold_build1_initializer (code, argtype, arg) 3073 : fold_build1 (code, argtype, arg); 3074} 3075 3076/* Return nonzero if REF is an lvalue valid for this language. 3077 Lvalues can be assigned, unless their type has TYPE_READONLY. 3078 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */ 3079 3080static int 3081lvalue_p (tree ref) 3082{ 3083 enum tree_code code = TREE_CODE (ref); 3084 3085 switch (code) 3086 { 3087 case REALPART_EXPR: 3088 case IMAGPART_EXPR: 3089 case COMPONENT_REF: 3090 return lvalue_p (TREE_OPERAND (ref, 0)); 3091 3092 case COMPOUND_LITERAL_EXPR: 3093 case STRING_CST: 3094 return 1; 3095 3096 case INDIRECT_REF: 3097 case ARRAY_REF: 3098 case VAR_DECL: 3099 case PARM_DECL: 3100 case RESULT_DECL: 3101 case ERROR_MARK: 3102 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE 3103 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE); 3104 3105 case BIND_EXPR: 3106 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE; 3107 3108 default: 3109 return 0; 3110 } 3111} 3112 3113/* Give an error for storing in something that is 'const'. */ 3114 3115static void 3116readonly_error (tree arg, enum lvalue_use use) 3117{ 3118 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement 3119 || use == lv_asm); 3120 /* Using this macro rather than (for example) arrays of messages 3121 ensures that all the format strings are checked at compile 3122 time. */ 3123#define READONLY_MSG(A, I, D, AS) (use == lv_assign ? (A) \ 3124 : (use == lv_increment ? (I) \ 3125 : (use == lv_decrement ? (D) : (AS)))) 3126 if (TREE_CODE (arg) == COMPONENT_REF) 3127 { 3128 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0)))) 3129 readonly_error (TREE_OPERAND (arg, 0), use); 3130 else 3131 error (READONLY_MSG (G_("assignment of read-only member %qD"), 3132 G_("increment of read-only member %qD"), 3133 G_("decrement of read-only member %qD"), 3134 G_("read-only member %qD used as %<asm%> output")), 3135 TREE_OPERAND (arg, 1)); 3136 } 3137 else if (TREE_CODE (arg) == VAR_DECL) 3138 error (READONLY_MSG (G_("assignment of read-only variable %qD"), 3139 G_("increment of read-only variable %qD"), 3140 G_("decrement of read-only variable %qD"), 3141 G_("read-only variable %qD used as %<asm%> output")), 3142 arg); 3143 else 3144 error (READONLY_MSG (G_("assignment of read-only location"), 3145 G_("increment of read-only location"), 3146 G_("decrement of read-only location"), 3147 G_("read-only location used as %<asm%> output"))); 3148} 3149 3150 3151/* Return nonzero if REF is an lvalue valid for this language; 3152 otherwise, print an error message and return zero. USE says 3153 how the lvalue is being used and so selects the error message. */ 3154 3155static int 3156lvalue_or_else (tree ref, enum lvalue_use use) 3157{ 3158 int win = lvalue_p (ref); 3159 3160 if (!win) 3161 lvalue_error (use); 3162 3163 return win; 3164} 3165 3166/* Mark EXP saying that we need to be able to take the 3167 address of it; it should not be allocated in a register. 3168 Returns true if successful. */ 3169 3170bool 3171c_mark_addressable (tree exp) 3172{ 3173 tree x = exp; 3174 3175 while (1) 3176 switch (TREE_CODE (x)) 3177 { 3178 case COMPONENT_REF: 3179 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1))) 3180 { 3181 error 3182 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1)); 3183 return false; 3184 } 3185 3186 /* ... fall through ... */ 3187 3188 case ADDR_EXPR: 3189 case ARRAY_REF: 3190 case REALPART_EXPR: 3191 case IMAGPART_EXPR: 3192 x = TREE_OPERAND (x, 0); 3193 break; 3194 3195 case COMPOUND_LITERAL_EXPR: 3196 case CONSTRUCTOR: 3197 TREE_ADDRESSABLE (x) = 1; 3198 return true; 3199 3200 case VAR_DECL: 3201 case CONST_DECL: 3202 case PARM_DECL: 3203 case RESULT_DECL: 3204 if (C_DECL_REGISTER (x) 3205 && DECL_NONLOCAL (x)) 3206 { 3207 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x)) 3208 { 3209 error 3210 ("global register variable %qD used in nested function", x); 3211 return false; 3212 } 3213 pedwarn ("register variable %qD used in nested function", x); 3214 } 3215 else if (C_DECL_REGISTER (x)) 3216 { 3217 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x)) 3218 error ("address of global register variable %qD requested", x); 3219 else 3220 error ("address of register variable %qD requested", x); 3221 return false; 3222 } 3223 3224 /* drops in */ 3225 case FUNCTION_DECL: 3226 TREE_ADDRESSABLE (x) = 1; 3227 /* drops out */ 3228 default: 3229 return true; 3230 } 3231} 3232 3233/* Build and return a conditional expression IFEXP ? OP1 : OP2. */ 3234 3235tree 3236build_conditional_expr (tree ifexp, tree op1, tree op2) 3237{ 3238 tree type1; 3239 tree type2; 3240 enum tree_code code1; 3241 enum tree_code code2; 3242 tree result_type = NULL; 3243 tree orig_op1 = op1, orig_op2 = op2; 3244 3245 /* Promote both alternatives. */ 3246 3247 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE) 3248 op1 = default_conversion (op1); 3249 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE) 3250 op2 = default_conversion (op2); 3251 3252 if (TREE_CODE (ifexp) == ERROR_MARK 3253 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK 3254 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK) 3255 return error_mark_node; 3256 3257 type1 = TREE_TYPE (op1); 3258 code1 = TREE_CODE (type1); 3259 type2 = TREE_TYPE (op2); 3260 code2 = TREE_CODE (type2); 3261 3262 /* C90 does not permit non-lvalue arrays in conditional expressions. 3263 In C99 they will be pointers by now. */ 3264 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE) 3265 { 3266 error ("non-lvalue array in conditional expression"); 3267 return error_mark_node; 3268 } 3269 3270 /* Quickly detect the usual case where op1 and op2 have the same type 3271 after promotion. */ 3272 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2)) 3273 { 3274 if (type1 == type2) 3275 result_type = type1; 3276 else 3277 result_type = TYPE_MAIN_VARIANT (type1); 3278 } 3279 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE 3280 || code1 == COMPLEX_TYPE) 3281 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE 3282 || code2 == COMPLEX_TYPE)) 3283 { 3284 result_type = c_common_type (type1, type2); 3285 3286 /* If -Wsign-compare, warn here if type1 and type2 have 3287 different signedness. We'll promote the signed to unsigned 3288 and later code won't know it used to be different. 3289 Do this check on the original types, so that explicit casts 3290 will be considered, but default promotions won't. */ 3291 if (warn_sign_compare && !skip_evaluation) 3292 { 3293 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1)); 3294 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2)); 3295 3296 if (unsigned_op1 ^ unsigned_op2) 3297 { 3298 bool ovf; 3299 3300 /* Do not warn if the result type is signed, since the 3301 signed type will only be chosen if it can represent 3302 all the values of the unsigned type. */ 3303 if (!TYPE_UNSIGNED (result_type)) 3304 /* OK */; 3305 /* Do not warn if the signed quantity is an unsuffixed 3306 integer literal (or some static constant expression 3307 involving such literals) and it is non-negative. */ 3308 else if ((unsigned_op2 3309 && tree_expr_nonnegative_warnv_p (op1, &ovf)) 3310 || (unsigned_op1 3311 && tree_expr_nonnegative_warnv_p (op2, &ovf))) 3312 /* OK */; 3313 else 3314 warning (0, "signed and unsigned type in conditional expression"); 3315 } 3316 } 3317 } 3318 else if (code1 == VOID_TYPE || code2 == VOID_TYPE) 3319 { 3320 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE)) 3321 pedwarn ("ISO C forbids conditional expr with only one void side"); 3322 result_type = void_type_node; 3323 } 3324 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE) 3325 { 3326 if (comp_target_types (type1, type2)) 3327 result_type = common_pointer_type (type1, type2); 3328 else if (null_pointer_constant_p (orig_op1)) 3329 result_type = qualify_type (type2, type1); 3330 else if (null_pointer_constant_p (orig_op2)) 3331 result_type = qualify_type (type1, type2); 3332 else if (VOID_TYPE_P (TREE_TYPE (type1))) 3333 { 3334 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE) 3335 pedwarn ("ISO C forbids conditional expr between " 3336 "%<void *%> and function pointer"); 3337 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1), 3338 TREE_TYPE (type2))); 3339 } 3340 else if (VOID_TYPE_P (TREE_TYPE (type2))) 3341 { 3342 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE) 3343 pedwarn ("ISO C forbids conditional expr between " 3344 "%<void *%> and function pointer"); 3345 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2), 3346 TREE_TYPE (type1))); 3347 } 3348 else 3349 { 3350 pedwarn ("pointer type mismatch in conditional expression"); 3351 result_type = build_pointer_type (void_type_node); 3352 } 3353 } 3354 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE) 3355 { 3356 if (!null_pointer_constant_p (orig_op2)) 3357 pedwarn ("pointer/integer type mismatch in conditional expression"); 3358 else 3359 { 3360 op2 = null_pointer_node; 3361 } 3362 result_type = type1; 3363 } 3364 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE) 3365 { 3366 if (!null_pointer_constant_p (orig_op1)) 3367 pedwarn ("pointer/integer type mismatch in conditional expression"); 3368 else 3369 { 3370 op1 = null_pointer_node; 3371 } 3372 result_type = type2; 3373 } 3374 3375 if (!result_type) 3376 { 3377 if (flag_cond_mismatch) 3378 result_type = void_type_node; 3379 else 3380 { 3381 error ("type mismatch in conditional expression"); 3382 return error_mark_node; 3383 } 3384 } 3385 3386 /* Merge const and volatile flags of the incoming types. */ 3387 result_type 3388 = build_type_variant (result_type, 3389 TREE_READONLY (op1) || TREE_READONLY (op2), 3390 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2)); 3391 3392 if (result_type != TREE_TYPE (op1)) 3393 op1 = convert_and_check (result_type, op1); 3394 if (result_type != TREE_TYPE (op2)) 3395 op2 = convert_and_check (result_type, op2); 3396 3397 return fold_build3 (COND_EXPR, result_type, ifexp, op1, op2); 3398} 3399 3400/* Return a compound expression that performs two expressions and 3401 returns the value of the second of them. */ 3402 3403tree 3404build_compound_expr (tree expr1, tree expr2) 3405{ 3406 if (!TREE_SIDE_EFFECTS (expr1)) 3407 { 3408 /* The left-hand operand of a comma expression is like an expression 3409 statement: with -Wextra or -Wunused, we should warn if it doesn't have 3410 any side-effects, unless it was explicitly cast to (void). */ 3411 if (warn_unused_value) 3412 { 3413 if (VOID_TYPE_P (TREE_TYPE (expr1)) 3414 && (TREE_CODE (expr1) == NOP_EXPR 3415 || TREE_CODE (expr1) == CONVERT_EXPR)) 3416 ; /* (void) a, b */ 3417 else if (VOID_TYPE_P (TREE_TYPE (expr1)) 3418 && TREE_CODE (expr1) == COMPOUND_EXPR 3419 && (TREE_CODE (TREE_OPERAND (expr1, 1)) == CONVERT_EXPR 3420 || TREE_CODE (TREE_OPERAND (expr1, 1)) == NOP_EXPR)) 3421 ; /* (void) a, (void) b, c */ 3422 else 3423 warning (0, "left-hand operand of comma expression has no effect"); 3424 } 3425 } 3426 3427 /* With -Wunused, we should also warn if the left-hand operand does have 3428 side-effects, but computes a value which is not used. For example, in 3429 `foo() + bar(), baz()' the result of the `+' operator is not used, 3430 so we should issue a warning. */ 3431 else if (warn_unused_value) 3432 warn_if_unused_value (expr1, input_location); 3433 3434 if (expr2 == error_mark_node) 3435 return error_mark_node; 3436 3437 return build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2); 3438} 3439 3440/* Build an expression representing a cast to type TYPE of expression EXPR. */ 3441 3442tree 3443build_c_cast (tree type, tree expr) 3444{ 3445 tree value = expr; 3446 3447 if (type == error_mark_node || expr == error_mark_node) 3448 return error_mark_node; 3449 3450 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing 3451 only in <protocol> qualifications. But when constructing cast expressions, 3452 the protocols do matter and must be kept around. */ 3453 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr))) 3454 return build1 (NOP_EXPR, type, expr); 3455 3456 type = TYPE_MAIN_VARIANT (type); 3457 3458 if (TREE_CODE (type) == ARRAY_TYPE) 3459 { 3460 error ("cast specifies array type"); 3461 return error_mark_node; 3462 } 3463 3464 if (TREE_CODE (type) == FUNCTION_TYPE) 3465 { 3466 error ("cast specifies function type"); 3467 return error_mark_node; 3468 } 3469 3470 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value))) 3471 { 3472 if (pedantic) 3473 { 3474 if (TREE_CODE (type) == RECORD_TYPE 3475 || TREE_CODE (type) == UNION_TYPE) 3476 pedwarn ("ISO C forbids casting nonscalar to the same type"); 3477 } 3478 } 3479 else if (TREE_CODE (type) == UNION_TYPE) 3480 { 3481 tree field; 3482 3483 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) 3484 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)), 3485 TYPE_MAIN_VARIANT (TREE_TYPE (value)))) 3486 break; 3487 3488 if (field) 3489 { 3490 tree t; 3491 3492 if (pedantic) 3493 pedwarn ("ISO C forbids casts to union type"); 3494 t = digest_init (type, 3495 build_constructor_single (type, field, value), 3496 true, 0); 3497 TREE_CONSTANT (t) = TREE_CONSTANT (value); 3498 TREE_INVARIANT (t) = TREE_INVARIANT (value); 3499 return t; 3500 } 3501 error ("cast to union type from type not present in union"); 3502 return error_mark_node; 3503 } 3504 else 3505 { 3506 tree otype, ovalue; 3507 3508 if (type == void_type_node) 3509 return build1 (CONVERT_EXPR, type, value); 3510 3511 otype = TREE_TYPE (value); 3512 3513 /* Optionally warn about potentially worrisome casts. */ 3514 3515 if (warn_cast_qual 3516 && TREE_CODE (type) == POINTER_TYPE 3517 && TREE_CODE (otype) == POINTER_TYPE) 3518 { 3519 tree in_type = type; 3520 tree in_otype = otype; 3521 int added = 0; 3522 int discarded = 0; 3523 3524 /* Check that the qualifiers on IN_TYPE are a superset of 3525 the qualifiers of IN_OTYPE. The outermost level of 3526 POINTER_TYPE nodes is uninteresting and we stop as soon 3527 as we hit a non-POINTER_TYPE node on either type. */ 3528 do 3529 { 3530 in_otype = TREE_TYPE (in_otype); 3531 in_type = TREE_TYPE (in_type); 3532 3533 /* GNU C allows cv-qualified function types. 'const' 3534 means the function is very pure, 'volatile' means it 3535 can't return. We need to warn when such qualifiers 3536 are added, not when they're taken away. */ 3537 if (TREE_CODE (in_otype) == FUNCTION_TYPE 3538 && TREE_CODE (in_type) == FUNCTION_TYPE) 3539 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype)); 3540 else 3541 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type)); 3542 } 3543 while (TREE_CODE (in_type) == POINTER_TYPE 3544 && TREE_CODE (in_otype) == POINTER_TYPE); 3545 3546 if (added) 3547 warning (0, "cast adds new qualifiers to function type"); 3548 3549 if (discarded) 3550 /* There are qualifiers present in IN_OTYPE that are not 3551 present in IN_TYPE. */ 3552 warning (0, "cast discards qualifiers from pointer target type"); 3553 } 3554 3555 /* Warn about possible alignment problems. */ 3556 if (STRICT_ALIGNMENT 3557 && TREE_CODE (type) == POINTER_TYPE 3558 && TREE_CODE (otype) == POINTER_TYPE 3559 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE 3560 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE 3561 /* Don't warn about opaque types, where the actual alignment 3562 restriction is unknown. */ 3563 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE 3564 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE) 3565 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode) 3566 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype))) 3567 warning (OPT_Wcast_align, 3568 "cast increases required alignment of target type"); 3569 3570 if (TREE_CODE (type) == INTEGER_TYPE 3571 && TREE_CODE (otype) == POINTER_TYPE 3572 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)) 3573 /* Unlike conversion of integers to pointers, where the 3574 warning is disabled for converting constants because 3575 of cases such as SIG_*, warn about converting constant 3576 pointers to integers. In some cases it may cause unwanted 3577 sign extension, and a warning is appropriate. */ 3578 warning (OPT_Wpointer_to_int_cast, 3579 "cast from pointer to integer of different size"); 3580 3581 if (TREE_CODE (value) == CALL_EXPR 3582 && TREE_CODE (type) != TREE_CODE (otype)) 3583 warning (OPT_Wbad_function_cast, "cast from function call of type %qT " 3584 "to non-matching type %qT", otype, type); 3585 3586 if (TREE_CODE (type) == POINTER_TYPE 3587 && TREE_CODE (otype) == INTEGER_TYPE 3588 && TYPE_PRECISION (type) != TYPE_PRECISION (otype) 3589 /* Don't warn about converting any constant. */ 3590 && !TREE_CONSTANT (value)) 3591 warning (OPT_Wint_to_pointer_cast, "cast to pointer from integer " 3592 "of different size"); 3593 3594 if (warn_strict_aliasing <= 2) 3595 strict_aliasing_warning (otype, type, expr); 3596 3597 /* If pedantic, warn for conversions between function and object 3598 pointer types, except for converting a null pointer constant 3599 to function pointer type. */ 3600 if (pedantic 3601 && TREE_CODE (type) == POINTER_TYPE 3602 && TREE_CODE (otype) == POINTER_TYPE 3603 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE 3604 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE) 3605 pedwarn ("ISO C forbids conversion of function pointer to object pointer type"); 3606 3607 if (pedantic 3608 && TREE_CODE (type) == POINTER_TYPE 3609 && TREE_CODE (otype) == POINTER_TYPE 3610 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE 3611 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE 3612 && !null_pointer_constant_p (value)) 3613 pedwarn ("ISO C forbids conversion of object pointer to function pointer type"); 3614 3615 ovalue = value; 3616 value = convert (type, value); 3617 3618 /* Ignore any integer overflow caused by the cast. */ 3619 if (TREE_CODE (value) == INTEGER_CST) 3620 { 3621 if (CONSTANT_CLASS_P (ovalue) 3622 && (TREE_OVERFLOW (ovalue) || TREE_CONSTANT_OVERFLOW (ovalue))) 3623 { 3624 /* Avoid clobbering a shared constant. */ 3625 value = copy_node (value); 3626 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue); 3627 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue); 3628 } 3629 else if (TREE_OVERFLOW (value) || TREE_CONSTANT_OVERFLOW (value)) 3630 /* Reset VALUE's overflow flags, ensuring constant sharing. */ 3631 value = build_int_cst_wide (TREE_TYPE (value), 3632 TREE_INT_CST_LOW (value), 3633 TREE_INT_CST_HIGH (value)); 3634 } 3635 } 3636 3637 /* Don't let a cast be an lvalue. */ 3638 if (value == expr) 3639 value = non_lvalue (value); 3640 3641 return value; 3642} 3643 3644/* Interpret a cast of expression EXPR to type TYPE. */ 3645tree 3646c_cast_expr (struct c_type_name *type_name, tree expr) 3647{ 3648 tree type; 3649 int saved_wsp = warn_strict_prototypes; 3650 3651 /* This avoids warnings about unprototyped casts on 3652 integers. E.g. "#define SIG_DFL (void(*)())0". */ 3653 if (TREE_CODE (expr) == INTEGER_CST) 3654 warn_strict_prototypes = 0; 3655 type = groktypename (type_name); 3656 warn_strict_prototypes = saved_wsp; 3657 3658 return build_c_cast (type, expr); 3659} 3660 3661/* Build an assignment expression of lvalue LHS from value RHS. 3662 MODIFYCODE is the code for a binary operator that we use 3663 to combine the old value of LHS with RHS to get the new value. 3664 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */ 3665 3666tree 3667build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs) 3668{ 3669 tree result; 3670 tree newrhs; 3671 tree lhstype = TREE_TYPE (lhs); 3672 tree olhstype = lhstype; 3673 3674 /* Types that aren't fully specified cannot be used in assignments. */ 3675 lhs = require_complete_type (lhs); 3676 3677 /* Avoid duplicate error messages from operands that had errors. */ 3678 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK) 3679 return error_mark_node; 3680 3681 if (!lvalue_or_else (lhs, lv_assign)) 3682 return error_mark_node; 3683 3684 STRIP_TYPE_NOPS (rhs); 3685 3686 newrhs = rhs; 3687 3688 /* If a binary op has been requested, combine the old LHS value with the RHS 3689 producing the value we should actually store into the LHS. */ 3690 3691 if (modifycode != NOP_EXPR) 3692 { 3693 lhs = stabilize_reference (lhs); 3694 newrhs = build_binary_op (modifycode, lhs, rhs, 1); 3695 } 3696 3697 /* Give an error for storing in something that is 'const'. */ 3698 3699 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype) 3700 || ((TREE_CODE (lhstype) == RECORD_TYPE 3701 || TREE_CODE (lhstype) == UNION_TYPE) 3702 && C_TYPE_FIELDS_READONLY (lhstype))) 3703 { 3704 readonly_error (lhs, lv_assign); 3705 return error_mark_node; 3706 } 3707 3708 /* If storing into a structure or union member, 3709 it has probably been given type `int'. 3710 Compute the type that would go with 3711 the actual amount of storage the member occupies. */ 3712 3713 if (TREE_CODE (lhs) == COMPONENT_REF 3714 && (TREE_CODE (lhstype) == INTEGER_TYPE 3715 || TREE_CODE (lhstype) == BOOLEAN_TYPE 3716 || TREE_CODE (lhstype) == REAL_TYPE 3717 || TREE_CODE (lhstype) == ENUMERAL_TYPE)) 3718 lhstype = TREE_TYPE (get_unwidened (lhs, 0)); 3719 3720 /* If storing in a field that is in actuality a short or narrower than one, 3721 we must store in the field in its actual type. */ 3722 3723 if (lhstype != TREE_TYPE (lhs)) 3724 { 3725 lhs = copy_node (lhs); 3726 TREE_TYPE (lhs) = lhstype; 3727 } 3728 3729 /* Convert new value to destination type. */ 3730 3731 newrhs = convert_for_assignment (lhstype, newrhs, ic_assign, 3732 NULL_TREE, NULL_TREE, 0); 3733 if (TREE_CODE (newrhs) == ERROR_MARK) 3734 return error_mark_node; 3735 3736 /* Emit ObjC write barrier, if necessary. */ 3737 if (c_dialect_objc () && flag_objc_gc) 3738 { 3739 result = objc_generate_write_barrier (lhs, modifycode, newrhs); 3740 if (result) 3741 return result; 3742 } 3743 3744 /* Scan operands. */ 3745 3746 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs); 3747 TREE_SIDE_EFFECTS (result) = 1; 3748 3749 /* If we got the LHS in a different type for storing in, 3750 convert the result back to the nominal type of LHS 3751 so that the value we return always has the same type 3752 as the LHS argument. */ 3753 3754 if (olhstype == TREE_TYPE (result)) 3755 return result; 3756 return convert_for_assignment (olhstype, result, ic_assign, 3757 NULL_TREE, NULL_TREE, 0); 3758} 3759 3760/* Convert value RHS to type TYPE as preparation for an assignment 3761 to an lvalue of type TYPE. 3762 The real work of conversion is done by `convert'. 3763 The purpose of this function is to generate error messages 3764 for assignments that are not allowed in C. 3765 ERRTYPE says whether it is argument passing, assignment, 3766 initialization or return. 3767 3768 FUNCTION is a tree for the function being called. 3769 PARMNUM is the number of the argument, for printing in error messages. */ 3770 3771static tree 3772convert_for_assignment (tree type, tree rhs, enum impl_conv errtype, 3773 tree fundecl, tree function, int parmnum) 3774{ 3775 enum tree_code codel = TREE_CODE (type); 3776 tree rhstype; 3777 enum tree_code coder; 3778 tree rname = NULL_TREE; 3779 bool objc_ok = false; 3780 3781 if (errtype == ic_argpass || errtype == ic_argpass_nonproto) 3782 { 3783 tree selector; 3784 /* Change pointer to function to the function itself for 3785 diagnostics. */ 3786 if (TREE_CODE (function) == ADDR_EXPR 3787 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL) 3788 function = TREE_OPERAND (function, 0); 3789 3790 /* Handle an ObjC selector specially for diagnostics. */ 3791 selector = objc_message_selector (); 3792 rname = function; 3793 if (selector && parmnum > 2) 3794 { 3795 rname = selector; 3796 parmnum -= 2; 3797 } 3798 } 3799 3800 /* This macro is used to emit diagnostics to ensure that all format 3801 strings are complete sentences, visible to gettext and checked at 3802 compile time. */ 3803#define WARN_FOR_ASSIGNMENT(AR, AS, IN, RE) \ 3804 do { \ 3805 switch (errtype) \ 3806 { \ 3807 case ic_argpass: \ 3808 pedwarn (AR, parmnum, rname); \ 3809 break; \ 3810 case ic_argpass_nonproto: \ 3811 warning (0, AR, parmnum, rname); \ 3812 break; \ 3813 case ic_assign: \ 3814 pedwarn (AS); \ 3815 break; \ 3816 case ic_init: \ 3817 pedwarn (IN); \ 3818 break; \ 3819 case ic_return: \ 3820 pedwarn (RE); \ 3821 break; \ 3822 default: \ 3823 gcc_unreachable (); \ 3824 } \ 3825 } while (0) 3826 3827 STRIP_TYPE_NOPS (rhs); 3828 3829 if (optimize && TREE_CODE (rhs) == VAR_DECL 3830 && TREE_CODE (TREE_TYPE (rhs)) != ARRAY_TYPE) 3831 rhs = decl_constant_value_for_broken_optimization (rhs); 3832 3833 rhstype = TREE_TYPE (rhs); 3834 coder = TREE_CODE (rhstype); 3835 3836 if (coder == ERROR_MARK) 3837 return error_mark_node; 3838 3839 if (c_dialect_objc ()) 3840 { 3841 int parmno; 3842 3843 switch (errtype) 3844 { 3845 case ic_return: 3846 parmno = 0; 3847 break; 3848 3849 case ic_assign: 3850 parmno = -1; 3851 break; 3852 3853 case ic_init: 3854 parmno = -2; 3855 break; 3856 3857 default: 3858 parmno = parmnum; 3859 break; 3860 } 3861 3862 objc_ok = objc_compare_types (type, rhstype, parmno, rname); 3863 } 3864 3865 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype)) 3866 return rhs; 3867 3868 if (coder == VOID_TYPE) 3869 { 3870 /* Except for passing an argument to an unprototyped function, 3871 this is a constraint violation. When passing an argument to 3872 an unprototyped function, it is compile-time undefined; 3873 making it a constraint in that case was rejected in 3874 DR#252. */ 3875 error ("void value not ignored as it ought to be"); 3876 return error_mark_node; 3877 } 3878 /* A type converts to a reference to it. 3879 This code doesn't fully support references, it's just for the 3880 special case of va_start and va_copy. */ 3881 if (codel == REFERENCE_TYPE 3882 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1) 3883 { 3884 if (!lvalue_p (rhs)) 3885 { 3886 error ("cannot pass rvalue to reference parameter"); 3887 return error_mark_node; 3888 } 3889 if (!c_mark_addressable (rhs)) 3890 return error_mark_node; 3891 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs); 3892 3893 /* We already know that these two types are compatible, but they 3894 may not be exactly identical. In fact, `TREE_TYPE (type)' is 3895 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is 3896 likely to be va_list, a typedef to __builtin_va_list, which 3897 is different enough that it will cause problems later. */ 3898 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type)) 3899 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs); 3900 3901 rhs = build1 (NOP_EXPR, type, rhs); 3902 return rhs; 3903 } 3904 /* Some types can interconvert without explicit casts. */ 3905 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE 3906 && vector_types_convertible_p (type, TREE_TYPE (rhs), true)) 3907 return convert (type, rhs); 3908 /* Arithmetic types all interconvert, and enum is treated like int. */ 3909 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE 3910 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE 3911 || codel == BOOLEAN_TYPE) 3912 && (coder == INTEGER_TYPE || coder == REAL_TYPE 3913 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE 3914 || coder == BOOLEAN_TYPE)) 3915 return convert_and_check (type, rhs); 3916 3917 /* Aggregates in different TUs might need conversion. */ 3918 if ((codel == RECORD_TYPE || codel == UNION_TYPE) 3919 && codel == coder 3920 && comptypes (type, rhstype)) 3921 return convert_and_check (type, rhs); 3922 3923 /* Conversion to a transparent union from its member types. 3924 This applies only to function arguments. */ 3925 if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type) 3926 && (errtype == ic_argpass || errtype == ic_argpass_nonproto)) 3927 { 3928 tree memb, marginal_memb = NULL_TREE; 3929 3930 for (memb = TYPE_FIELDS (type); memb ; memb = TREE_CHAIN (memb)) 3931 { 3932 tree memb_type = TREE_TYPE (memb); 3933 3934 if (comptypes (TYPE_MAIN_VARIANT (memb_type), 3935 TYPE_MAIN_VARIANT (rhstype))) 3936 break; 3937 3938 if (TREE_CODE (memb_type) != POINTER_TYPE) 3939 continue; 3940 3941 if (coder == POINTER_TYPE) 3942 { 3943 tree ttl = TREE_TYPE (memb_type); 3944 tree ttr = TREE_TYPE (rhstype); 3945 3946 /* Any non-function converts to a [const][volatile] void * 3947 and vice versa; otherwise, targets must be the same. 3948 Meanwhile, the lhs target must have all the qualifiers of 3949 the rhs. */ 3950 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr) 3951 || comp_target_types (memb_type, rhstype)) 3952 { 3953 /* If this type won't generate any warnings, use it. */ 3954 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr) 3955 || ((TREE_CODE (ttr) == FUNCTION_TYPE 3956 && TREE_CODE (ttl) == FUNCTION_TYPE) 3957 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr)) 3958 == TYPE_QUALS (ttr)) 3959 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr)) 3960 == TYPE_QUALS (ttl)))) 3961 break; 3962 3963 /* Keep looking for a better type, but remember this one. */ 3964 if (!marginal_memb) 3965 marginal_memb = memb; 3966 } 3967 } 3968 3969 /* Can convert integer zero to any pointer type. */ 3970 if (null_pointer_constant_p (rhs)) 3971 { 3972 rhs = null_pointer_node; 3973 break; 3974 } 3975 } 3976 3977 if (memb || marginal_memb) 3978 { 3979 if (!memb) 3980 { 3981 /* We have only a marginally acceptable member type; 3982 it needs a warning. */ 3983 tree ttl = TREE_TYPE (TREE_TYPE (marginal_memb)); 3984 tree ttr = TREE_TYPE (rhstype); 3985 3986 /* Const and volatile mean something different for function 3987 types, so the usual warnings are not appropriate. */ 3988 if (TREE_CODE (ttr) == FUNCTION_TYPE 3989 && TREE_CODE (ttl) == FUNCTION_TYPE) 3990 { 3991 /* Because const and volatile on functions are 3992 restrictions that say the function will not do 3993 certain things, it is okay to use a const or volatile 3994 function where an ordinary one is wanted, but not 3995 vice-versa. */ 3996 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr)) 3997 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE " 3998 "makes qualified function " 3999 "pointer from unqualified"), 4000 G_("assignment makes qualified " 4001 "function pointer from " 4002 "unqualified"), 4003 G_("initialization makes qualified " 4004 "function pointer from " 4005 "unqualified"), 4006 G_("return makes qualified function " 4007 "pointer from unqualified")); 4008 } 4009 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl)) 4010 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards " 4011 "qualifiers from pointer target type"), 4012 G_("assignment discards qualifiers " 4013 "from pointer target type"), 4014 G_("initialization discards qualifiers " 4015 "from pointer target type"), 4016 G_("return discards qualifiers from " 4017 "pointer target type")); 4018 4019 memb = marginal_memb; 4020 } 4021 4022 if (pedantic && (!fundecl || !DECL_IN_SYSTEM_HEADER (fundecl))) 4023 pedwarn ("ISO C prohibits argument conversion to union type"); 4024 4025 return build_constructor_single (type, memb, rhs); 4026 } 4027 } 4028 4029 /* Conversions among pointers */ 4030 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE) 4031 && (coder == codel)) 4032 { 4033 tree ttl = TREE_TYPE (type); 4034 tree ttr = TREE_TYPE (rhstype); 4035 tree mvl = ttl; 4036 tree mvr = ttr; 4037 bool is_opaque_pointer; 4038 int target_cmp = 0; /* Cache comp_target_types () result. */ 4039 4040 if (TREE_CODE (mvl) != ARRAY_TYPE) 4041 mvl = TYPE_MAIN_VARIANT (mvl); 4042 if (TREE_CODE (mvr) != ARRAY_TYPE) 4043 mvr = TYPE_MAIN_VARIANT (mvr); 4044 /* Opaque pointers are treated like void pointers. */ 4045 is_opaque_pointer = (targetm.vector_opaque_p (type) 4046 || targetm.vector_opaque_p (rhstype)) 4047 && TREE_CODE (ttl) == VECTOR_TYPE 4048 && TREE_CODE (ttr) == VECTOR_TYPE; 4049 4050 /* C++ does not allow the implicit conversion void* -> T*. However, 4051 for the purpose of reducing the number of false positives, we 4052 tolerate the special case of 4053 4054 int *p = NULL; 4055 4056 where NULL is typically defined in C to be '(void *) 0'. */ 4057 if (VOID_TYPE_P (ttr) && rhs != null_pointer_node && !VOID_TYPE_P (ttl)) 4058 warning (OPT_Wc___compat, "request for implicit conversion from " 4059 "%qT to %qT not permitted in C++", rhstype, type); 4060 4061 /* Check if the right-hand side has a format attribute but the 4062 left-hand side doesn't. */ 4063 if (warn_missing_format_attribute 4064 && check_missing_format_attribute (type, rhstype)) 4065 { 4066 switch (errtype) 4067 { 4068 case ic_argpass: 4069 case ic_argpass_nonproto: 4070 warning (OPT_Wmissing_format_attribute, 4071 "argument %d of %qE might be " 4072 "a candidate for a format attribute", 4073 parmnum, rname); 4074 break; 4075 case ic_assign: 4076 warning (OPT_Wmissing_format_attribute, 4077 "assignment left-hand side might be " 4078 "a candidate for a format attribute"); 4079 break; 4080 case ic_init: 4081 warning (OPT_Wmissing_format_attribute, 4082 "initialization left-hand side might be " 4083 "a candidate for a format attribute"); 4084 break; 4085 case ic_return: 4086 warning (OPT_Wmissing_format_attribute, 4087 "return type might be " 4088 "a candidate for a format attribute"); 4089 break; 4090 default: 4091 gcc_unreachable (); 4092 } 4093 } 4094 4095 /* Any non-function converts to a [const][volatile] void * 4096 and vice versa; otherwise, targets must be the same. 4097 Meanwhile, the lhs target must have all the qualifiers of the rhs. */ 4098 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr) 4099 || (target_cmp = comp_target_types (type, rhstype)) 4100 || is_opaque_pointer 4101 || (c_common_unsigned_type (mvl) 4102 == c_common_unsigned_type (mvr))) 4103 { 4104 if (pedantic 4105 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE) 4106 || 4107 (VOID_TYPE_P (ttr) 4108 && !null_pointer_constant_p (rhs) 4109 && TREE_CODE (ttl) == FUNCTION_TYPE))) 4110 WARN_FOR_ASSIGNMENT (G_("ISO C forbids passing argument %d of " 4111 "%qE between function pointer " 4112 "and %<void *%>"), 4113 G_("ISO C forbids assignment between " 4114 "function pointer and %<void *%>"), 4115 G_("ISO C forbids initialization between " 4116 "function pointer and %<void *%>"), 4117 G_("ISO C forbids return between function " 4118 "pointer and %<void *%>")); 4119 /* Const and volatile mean something different for function types, 4120 so the usual warnings are not appropriate. */ 4121 else if (TREE_CODE (ttr) != FUNCTION_TYPE 4122 && TREE_CODE (ttl) != FUNCTION_TYPE) 4123 { 4124 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl)) 4125 { 4126 /* Types differing only by the presence of the 'volatile' 4127 qualifier are acceptable if the 'volatile' has been added 4128 in by the Objective-C EH machinery. */ 4129 if (!objc_type_quals_match (ttl, ttr)) 4130 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards " 4131 "qualifiers from pointer target type"), 4132 G_("assignment discards qualifiers " 4133 "from pointer target type"), 4134 G_("initialization discards qualifiers " 4135 "from pointer target type"), 4136 G_("return discards qualifiers from " 4137 "pointer target type")); 4138 } 4139 /* If this is not a case of ignoring a mismatch in signedness, 4140 no warning. */ 4141 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr) 4142 || target_cmp) 4143 ; 4144 /* If there is a mismatch, do warn. */ 4145 else if (warn_pointer_sign) 4146 WARN_FOR_ASSIGNMENT (G_("pointer targets in passing argument " 4147 "%d of %qE differ in signedness"), 4148 G_("pointer targets in assignment " 4149 "differ in signedness"), 4150 G_("pointer targets in initialization " 4151 "differ in signedness"), 4152 G_("pointer targets in return differ " 4153 "in signedness")); 4154 } 4155 else if (TREE_CODE (ttl) == FUNCTION_TYPE 4156 && TREE_CODE (ttr) == FUNCTION_TYPE) 4157 { 4158 /* Because const and volatile on functions are restrictions 4159 that say the function will not do certain things, 4160 it is okay to use a const or volatile function 4161 where an ordinary one is wanted, but not vice-versa. */ 4162 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr)) 4163 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes " 4164 "qualified function pointer " 4165 "from unqualified"), 4166 G_("assignment makes qualified function " 4167 "pointer from unqualified"), 4168 G_("initialization makes qualified " 4169 "function pointer from unqualified"), 4170 G_("return makes qualified function " 4171 "pointer from unqualified")); 4172 } 4173 } 4174 else 4175 /* Avoid warning about the volatile ObjC EH puts on decls. */ 4176 if (!objc_ok) 4177 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE from " 4178 "incompatible pointer type"), 4179 G_("assignment from incompatible pointer type"), 4180 G_("initialization from incompatible " 4181 "pointer type"), 4182 G_("return from incompatible pointer type")); 4183 4184 return convert (type, rhs); 4185 } 4186 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE) 4187 { 4188 /* ??? This should not be an error when inlining calls to 4189 unprototyped functions. */ 4190 error ("invalid use of non-lvalue array"); 4191 return error_mark_node; 4192 } 4193 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE) 4194 { 4195 /* An explicit constant 0 can convert to a pointer, 4196 or one that results from arithmetic, even including 4197 a cast to integer type. */ 4198 if (!null_pointer_constant_p (rhs)) 4199 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes " 4200 "pointer from integer without a cast"), 4201 G_("assignment makes pointer from integer " 4202 "without a cast"), 4203 G_("initialization makes pointer from " 4204 "integer without a cast"), 4205 G_("return makes pointer from integer " 4206 "without a cast")); 4207 4208 return convert (type, rhs); 4209 } 4210 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE) 4211 { 4212 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes integer " 4213 "from pointer without a cast"), 4214 G_("assignment makes integer from pointer " 4215 "without a cast"), 4216 G_("initialization makes integer from pointer " 4217 "without a cast"), 4218 G_("return makes integer from pointer " 4219 "without a cast")); 4220 return convert (type, rhs); 4221 } 4222 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE) 4223 return convert (type, rhs); 4224 4225 switch (errtype) 4226 { 4227 case ic_argpass: 4228 case ic_argpass_nonproto: 4229 /* ??? This should not be an error when inlining calls to 4230 unprototyped functions. */ 4231 error ("incompatible type for argument %d of %qE", parmnum, rname); 4232 break; 4233 case ic_assign: 4234 error ("incompatible types in assignment"); 4235 break; 4236 case ic_init: 4237 error ("incompatible types in initialization"); 4238 break; 4239 case ic_return: 4240 error ("incompatible types in return"); 4241 break; 4242 default: 4243 gcc_unreachable (); 4244 } 4245 4246 return error_mark_node; 4247} 4248 4249/* Convert VALUE for assignment into inlined parameter PARM. ARGNUM 4250 is used for error and warning reporting and indicates which argument 4251 is being processed. */ 4252 4253tree 4254c_convert_parm_for_inlining (tree parm, tree value, tree fn, int argnum) 4255{ 4256 tree ret, type; 4257 4258 /* If FN was prototyped at the call site, the value has been converted 4259 already in convert_arguments. 4260 However, we might see a prototype now that was not in place when 4261 the function call was seen, so check that the VALUE actually matches 4262 PARM before taking an early exit. */ 4263 if (!value 4264 || (TYPE_ARG_TYPES (TREE_TYPE (fn)) 4265 && (TYPE_MAIN_VARIANT (TREE_TYPE (parm)) 4266 == TYPE_MAIN_VARIANT (TREE_TYPE (value))))) 4267 return value; 4268 4269 type = TREE_TYPE (parm); 4270 ret = convert_for_assignment (type, value, 4271 ic_argpass_nonproto, fn, 4272 fn, argnum); 4273 if (targetm.calls.promote_prototypes (TREE_TYPE (fn)) 4274 && INTEGRAL_TYPE_P (type) 4275 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))) 4276 ret = default_conversion (ret); 4277 return ret; 4278} 4279 4280/* If VALUE is a compound expr all of whose expressions are constant, then 4281 return its value. Otherwise, return error_mark_node. 4282 4283 This is for handling COMPOUND_EXPRs as initializer elements 4284 which is allowed with a warning when -pedantic is specified. */ 4285 4286static tree 4287valid_compound_expr_initializer (tree value, tree endtype) 4288{ 4289 if (TREE_CODE (value) == COMPOUND_EXPR) 4290 { 4291 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype) 4292 == error_mark_node) 4293 return error_mark_node; 4294 return valid_compound_expr_initializer (TREE_OPERAND (value, 1), 4295 endtype); 4296 } 4297 else if (!initializer_constant_valid_p (value, endtype)) 4298 return error_mark_node; 4299 else 4300 return value; 4301} 4302 4303/* Perform appropriate conversions on the initial value of a variable, 4304 store it in the declaration DECL, 4305 and print any error messages that are appropriate. 4306 If the init is invalid, store an ERROR_MARK. */ 4307 4308void 4309store_init_value (tree decl, tree init) 4310{ 4311 tree value, type; 4312 4313 /* If variable's type was invalidly declared, just ignore it. */ 4314 4315 type = TREE_TYPE (decl); 4316 if (TREE_CODE (type) == ERROR_MARK) 4317 return; 4318 4319 /* Digest the specified initializer into an expression. */ 4320 4321 value = digest_init (type, init, true, TREE_STATIC (decl)); 4322 4323 /* Store the expression if valid; else report error. */ 4324 4325 if (!in_system_header 4326 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl)) 4327 warning (OPT_Wtraditional, "traditional C rejects automatic " 4328 "aggregate initialization"); 4329 4330 DECL_INITIAL (decl) = value; 4331 4332 /* ANSI wants warnings about out-of-range constant initializers. */ 4333 STRIP_TYPE_NOPS (value); 4334 constant_expression_warning (value); 4335 4336 /* Check if we need to set array size from compound literal size. */ 4337 if (TREE_CODE (type) == ARRAY_TYPE 4338 && TYPE_DOMAIN (type) == 0 4339 && value != error_mark_node) 4340 { 4341 tree inside_init = init; 4342 4343 STRIP_TYPE_NOPS (inside_init); 4344 inside_init = fold (inside_init); 4345 4346 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR) 4347 { 4348 tree cldecl = COMPOUND_LITERAL_EXPR_DECL (inside_init); 4349 4350 if (TYPE_DOMAIN (TREE_TYPE (cldecl))) 4351 { 4352 /* For int foo[] = (int [3]){1}; we need to set array size 4353 now since later on array initializer will be just the 4354 brace enclosed list of the compound literal. */ 4355 type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type)); 4356 TREE_TYPE (decl) = type; 4357 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (cldecl)); 4358 layout_type (type); 4359 layout_decl (cldecl, 0); 4360 } 4361 } 4362 } 4363} 4364 4365/* Methods for storing and printing names for error messages. */ 4366 4367/* Implement a spelling stack that allows components of a name to be pushed 4368 and popped. Each element on the stack is this structure. */ 4369 4370struct spelling 4371{ 4372 int kind; 4373 union 4374 { 4375 unsigned HOST_WIDE_INT i; 4376 const char *s; 4377 } u; 4378}; 4379 4380#define SPELLING_STRING 1 4381#define SPELLING_MEMBER 2 4382#define SPELLING_BOUNDS 3 4383 4384static struct spelling *spelling; /* Next stack element (unused). */ 4385static struct spelling *spelling_base; /* Spelling stack base. */ 4386static int spelling_size; /* Size of the spelling stack. */ 4387 4388/* Macros to save and restore the spelling stack around push_... functions. 4389 Alternative to SAVE_SPELLING_STACK. */ 4390 4391#define SPELLING_DEPTH() (spelling - spelling_base) 4392#define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH)) 4393 4394/* Push an element on the spelling stack with type KIND and assign VALUE 4395 to MEMBER. */ 4396 4397#define PUSH_SPELLING(KIND, VALUE, MEMBER) \ 4398{ \ 4399 int depth = SPELLING_DEPTH (); \ 4400 \ 4401 if (depth >= spelling_size) \ 4402 { \ 4403 spelling_size += 10; \ 4404 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \ 4405 spelling_size); \ 4406 RESTORE_SPELLING_DEPTH (depth); \ 4407 } \ 4408 \ 4409 spelling->kind = (KIND); \ 4410 spelling->MEMBER = (VALUE); \ 4411 spelling++; \ 4412} 4413 4414/* Push STRING on the stack. Printed literally. */ 4415 4416static void 4417push_string (const char *string) 4418{ 4419 PUSH_SPELLING (SPELLING_STRING, string, u.s); 4420} 4421 4422/* Push a member name on the stack. Printed as '.' STRING. */ 4423 4424static void 4425push_member_name (tree decl) 4426{ 4427 const char *const string 4428 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>"; 4429 PUSH_SPELLING (SPELLING_MEMBER, string, u.s); 4430} 4431 4432/* Push an array bounds on the stack. Printed as [BOUNDS]. */ 4433 4434static void 4435push_array_bounds (unsigned HOST_WIDE_INT bounds) 4436{ 4437 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i); 4438} 4439 4440/* Compute the maximum size in bytes of the printed spelling. */ 4441 4442static int 4443spelling_length (void) 4444{ 4445 int size = 0; 4446 struct spelling *p; 4447 4448 for (p = spelling_base; p < spelling; p++) 4449 { 4450 if (p->kind == SPELLING_BOUNDS) 4451 size += 25; 4452 else 4453 size += strlen (p->u.s) + 1; 4454 } 4455 4456 return size; 4457} 4458 4459/* Print the spelling to BUFFER and return it. */ 4460 4461static char * 4462print_spelling (char *buffer) 4463{ 4464 char *d = buffer; 4465 struct spelling *p; 4466 4467 for (p = spelling_base; p < spelling; p++) 4468 if (p->kind == SPELLING_BOUNDS) 4469 { 4470 sprintf (d, "[" HOST_WIDE_INT_PRINT_UNSIGNED "]", p->u.i); 4471 d += strlen (d); 4472 } 4473 else 4474 { 4475 const char *s; 4476 if (p->kind == SPELLING_MEMBER) 4477 *d++ = '.'; 4478 for (s = p->u.s; (*d = *s++); d++) 4479 ; 4480 } 4481 *d++ = '\0'; 4482 return buffer; 4483} 4484 4485/* Issue an error message for a bad initializer component. 4486 MSGID identifies the message. 4487 The component name is taken from the spelling stack. */ 4488 4489void 4490error_init (const char *msgid) 4491{ 4492 char *ofwhat; 4493 4494 error ("%s", _(msgid)); 4495 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1)); 4496 if (*ofwhat) 4497 error ("(near initialization for %qs)", ofwhat); 4498} 4499 4500/* Issue a pedantic warning for a bad initializer component. 4501 MSGID identifies the message. 4502 The component name is taken from the spelling stack. */ 4503 4504void 4505pedwarn_init (const char *msgid) 4506{ 4507 char *ofwhat; 4508 4509 pedwarn ("%s", _(msgid)); 4510 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1)); 4511 if (*ofwhat) 4512 pedwarn ("(near initialization for %qs)", ofwhat); 4513} 4514 4515/* Issue a warning for a bad initializer component. 4516 MSGID identifies the message. 4517 The component name is taken from the spelling stack. */ 4518 4519static void 4520warning_init (const char *msgid) 4521{ 4522 char *ofwhat; 4523 4524 warning (0, "%s", _(msgid)); 4525 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1)); 4526 if (*ofwhat) 4527 warning (0, "(near initialization for %qs)", ofwhat); 4528} 4529 4530/* If TYPE is an array type and EXPR is a parenthesized string 4531 constant, warn if pedantic that EXPR is being used to initialize an 4532 object of type TYPE. */ 4533 4534void 4535maybe_warn_string_init (tree type, struct c_expr expr) 4536{ 4537 if (pedantic 4538 && TREE_CODE (type) == ARRAY_TYPE 4539 && TREE_CODE (expr.value) == STRING_CST 4540 && expr.original_code != STRING_CST) 4541 pedwarn_init ("array initialized from parenthesized string constant"); 4542} 4543 4544/* Digest the parser output INIT as an initializer for type TYPE. 4545 Return a C expression of type TYPE to represent the initial value. 4546 4547 If INIT is a string constant, STRICT_STRING is true if it is 4548 unparenthesized or we should not warn here for it being parenthesized. 4549 For other types of INIT, STRICT_STRING is not used. 4550 4551 REQUIRE_CONSTANT requests an error if non-constant initializers or 4552 elements are seen. */ 4553 4554static tree 4555digest_init (tree type, tree init, bool strict_string, int require_constant) 4556{ 4557 enum tree_code code = TREE_CODE (type); 4558 tree inside_init = init; 4559 4560 if (type == error_mark_node 4561 || !init 4562 || init == error_mark_node 4563 || TREE_TYPE (init) == error_mark_node) 4564 return error_mark_node; 4565 4566 STRIP_TYPE_NOPS (inside_init); 4567 4568 inside_init = fold (inside_init); 4569 4570 /* Initialization of an array of chars from a string constant 4571 optionally enclosed in braces. */ 4572 4573 if (code == ARRAY_TYPE && inside_init 4574 && TREE_CODE (inside_init) == STRING_CST) 4575 { 4576 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type)); 4577 /* Note that an array could be both an array of character type 4578 and an array of wchar_t if wchar_t is signed char or unsigned 4579 char. */ 4580 bool char_array = (typ1 == char_type_node 4581 || typ1 == signed_char_type_node 4582 || typ1 == unsigned_char_type_node); 4583 bool wchar_array = !!comptypes (typ1, wchar_type_node); 4584 if (char_array || wchar_array) 4585 { 4586 struct c_expr expr; 4587 bool char_string; 4588 expr.value = inside_init; 4589 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK); 4590 maybe_warn_string_init (type, expr); 4591 4592 char_string 4593 = (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init))) 4594 == char_type_node); 4595 4596 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)), 4597 TYPE_MAIN_VARIANT (type))) 4598 return inside_init; 4599 4600 if (!wchar_array && !char_string) 4601 { 4602 error_init ("char-array initialized from wide string"); 4603 return error_mark_node; 4604 } 4605 if (char_string && !char_array) 4606 { 4607 error_init ("wchar_t-array initialized from non-wide string"); 4608 return error_mark_node; 4609 } 4610 4611 TREE_TYPE (inside_init) = type; 4612 if (TYPE_DOMAIN (type) != 0 4613 && TYPE_SIZE (type) != 0 4614 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST 4615 /* Subtract 1 (or sizeof (wchar_t)) 4616 because it's ok to ignore the terminating null char 4617 that is counted in the length of the constant. */ 4618 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type), 4619 TREE_STRING_LENGTH (inside_init) 4620 - ((TYPE_PRECISION (typ1) 4621 != TYPE_PRECISION (char_type_node)) 4622 ? (TYPE_PRECISION (wchar_type_node) 4623 / BITS_PER_UNIT) 4624 : 1))) 4625 pedwarn_init ("initializer-string for array of chars is too long"); 4626 4627 return inside_init; 4628 } 4629 else if (INTEGRAL_TYPE_P (typ1)) 4630 { 4631 error_init ("array of inappropriate type initialized " 4632 "from string constant"); 4633 return error_mark_node; 4634 } 4635 } 4636 4637 /* Build a VECTOR_CST from a *constant* vector constructor. If the 4638 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt 4639 below and handle as a constructor. */ 4640 if (code == VECTOR_TYPE 4641 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE 4642 && vector_types_convertible_p (TREE_TYPE (inside_init), type, true) 4643 && TREE_CONSTANT (inside_init)) 4644 { 4645 if (TREE_CODE (inside_init) == VECTOR_CST 4646 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)), 4647 TYPE_MAIN_VARIANT (type))) 4648 return inside_init; 4649 4650 if (TREE_CODE (inside_init) == CONSTRUCTOR) 4651 { 4652 unsigned HOST_WIDE_INT ix; 4653 tree value; 4654 bool constant_p = true; 4655 4656 /* Iterate through elements and check if all constructor 4657 elements are *_CSTs. */ 4658 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (inside_init), ix, value) 4659 if (!CONSTANT_CLASS_P (value)) 4660 { 4661 constant_p = false; 4662 break; 4663 } 4664 4665 if (constant_p) 4666 return build_vector_from_ctor (type, 4667 CONSTRUCTOR_ELTS (inside_init)); 4668 } 4669 } 4670 4671 /* Any type can be initialized 4672 from an expression of the same type, optionally with braces. */ 4673 4674 if (inside_init && TREE_TYPE (inside_init) != 0 4675 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)), 4676 TYPE_MAIN_VARIANT (type)) 4677 || (code == ARRAY_TYPE 4678 && comptypes (TREE_TYPE (inside_init), type)) 4679 || (code == VECTOR_TYPE 4680 && comptypes (TREE_TYPE (inside_init), type)) 4681 || (code == POINTER_TYPE 4682 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE 4683 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)), 4684 TREE_TYPE (type))))) 4685 { 4686 if (code == POINTER_TYPE) 4687 { 4688 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE) 4689 { 4690 if (TREE_CODE (inside_init) == STRING_CST 4691 || TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR) 4692 inside_init = array_to_pointer_conversion (inside_init); 4693 else 4694 { 4695 error_init ("invalid use of non-lvalue array"); 4696 return error_mark_node; 4697 } 4698 } 4699 } 4700 4701 if (code == VECTOR_TYPE) 4702 /* Although the types are compatible, we may require a 4703 conversion. */ 4704 inside_init = convert (type, inside_init); 4705 4706 if (require_constant 4707 && (code == VECTOR_TYPE || !flag_isoc99) 4708 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR) 4709 { 4710 /* As an extension, allow initializing objects with static storage 4711 duration with compound literals (which are then treated just as 4712 the brace enclosed list they contain). Also allow this for 4713 vectors, as we can only assign them with compound literals. */ 4714 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init); 4715 inside_init = DECL_INITIAL (decl); 4716 } 4717 4718 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST 4719 && TREE_CODE (inside_init) != CONSTRUCTOR) 4720 { 4721 error_init ("array initialized from non-constant array expression"); 4722 return error_mark_node; 4723 } 4724 4725 if (optimize && TREE_CODE (inside_init) == VAR_DECL) 4726 inside_init = decl_constant_value_for_broken_optimization (inside_init); 4727 4728 /* Compound expressions can only occur here if -pedantic or 4729 -pedantic-errors is specified. In the later case, we always want 4730 an error. In the former case, we simply want a warning. */ 4731 if (require_constant && pedantic 4732 && TREE_CODE (inside_init) == COMPOUND_EXPR) 4733 { 4734 inside_init 4735 = valid_compound_expr_initializer (inside_init, 4736 TREE_TYPE (inside_init)); 4737 if (inside_init == error_mark_node) 4738 error_init ("initializer element is not constant"); 4739 else 4740 pedwarn_init ("initializer element is not constant"); 4741 if (flag_pedantic_errors) 4742 inside_init = error_mark_node; 4743 } 4744 else if (require_constant 4745 && !initializer_constant_valid_p (inside_init, 4746 TREE_TYPE (inside_init))) 4747 { 4748 error_init ("initializer element is not constant"); 4749 inside_init = error_mark_node; 4750 } 4751 4752 /* Added to enable additional -Wmissing-format-attribute warnings. */ 4753 if (TREE_CODE (TREE_TYPE (inside_init)) == POINTER_TYPE) 4754 inside_init = convert_for_assignment (type, inside_init, ic_init, NULL_TREE, 4755 NULL_TREE, 0); 4756 return inside_init; 4757 } 4758 4759 /* Handle scalar types, including conversions. */ 4760 4761 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE 4762 || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE 4763 || code == VECTOR_TYPE) 4764 { 4765 if (TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE 4766 && (TREE_CODE (init) == STRING_CST 4767 || TREE_CODE (init) == COMPOUND_LITERAL_EXPR)) 4768 init = array_to_pointer_conversion (init); 4769 inside_init 4770 = convert_for_assignment (type, init, ic_init, 4771 NULL_TREE, NULL_TREE, 0); 4772 4773 /* Check to see if we have already given an error message. */ 4774 if (inside_init == error_mark_node) 4775 ; 4776 else if (require_constant && !TREE_CONSTANT (inside_init)) 4777 { 4778 error_init ("initializer element is not constant"); 4779 inside_init = error_mark_node; 4780 } 4781 else if (require_constant 4782 && !initializer_constant_valid_p (inside_init, 4783 TREE_TYPE (inside_init))) 4784 { 4785 error_init ("initializer element is not computable at load time"); 4786 inside_init = error_mark_node; 4787 } 4788 4789 return inside_init; 4790 } 4791 4792 /* Come here only for records and arrays. */ 4793 4794 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST) 4795 { 4796 error_init ("variable-sized object may not be initialized"); 4797 return error_mark_node; 4798 } 4799 4800 error_init ("invalid initializer"); 4801 return error_mark_node; 4802} 4803 4804/* Handle initializers that use braces. */ 4805 4806/* Type of object we are accumulating a constructor for. 4807 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */ 4808static tree constructor_type; 4809 4810/* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields 4811 left to fill. */ 4812static tree constructor_fields; 4813 4814/* For an ARRAY_TYPE, this is the specified index 4815 at which to store the next element we get. */ 4816static tree constructor_index; 4817 4818/* For an ARRAY_TYPE, this is the maximum index. */ 4819static tree constructor_max_index; 4820 4821/* For a RECORD_TYPE, this is the first field not yet written out. */ 4822static tree constructor_unfilled_fields; 4823 4824/* For an ARRAY_TYPE, this is the index of the first element 4825 not yet written out. */ 4826static tree constructor_unfilled_index; 4827 4828/* In a RECORD_TYPE, the byte index of the next consecutive field. 4829 This is so we can generate gaps between fields, when appropriate. */ 4830static tree constructor_bit_index; 4831 4832/* If we are saving up the elements rather than allocating them, 4833 this is the list of elements so far (in reverse order, 4834 most recent first). */ 4835static VEC(constructor_elt,gc) *constructor_elements; 4836 4837/* 1 if constructor should be incrementally stored into a constructor chain, 4838 0 if all the elements should be kept in AVL tree. */ 4839static int constructor_incremental; 4840 4841/* 1 if so far this constructor's elements are all compile-time constants. */ 4842static int constructor_constant; 4843 4844/* 1 if so far this constructor's elements are all valid address constants. */ 4845static int constructor_simple; 4846 4847/* 1 if this constructor is erroneous so far. */ 4848static int constructor_erroneous; 4849 4850/* Structure for managing pending initializer elements, organized as an 4851 AVL tree. */ 4852 4853struct init_node 4854{ 4855 struct init_node *left, *right; 4856 struct init_node *parent; 4857 int balance; 4858 tree purpose; 4859 tree value; 4860}; 4861 4862/* Tree of pending elements at this constructor level. 4863 These are elements encountered out of order 4864 which belong at places we haven't reached yet in actually 4865 writing the output. 4866 Will never hold tree nodes across GC runs. */ 4867static struct init_node *constructor_pending_elts; 4868 4869/* The SPELLING_DEPTH of this constructor. */ 4870static int constructor_depth; 4871 4872/* DECL node for which an initializer is being read. 4873 0 means we are reading a constructor expression 4874 such as (struct foo) {...}. */ 4875static tree constructor_decl; 4876 4877/* Nonzero if this is an initializer for a top-level decl. */ 4878static int constructor_top_level; 4879 4880/* Nonzero if there were any member designators in this initializer. */ 4881static int constructor_designated; 4882 4883/* Nesting depth of designator list. */ 4884static int designator_depth; 4885 4886/* Nonzero if there were diagnosed errors in this designator list. */ 4887static int designator_erroneous; 4888 4889 4890/* This stack has a level for each implicit or explicit level of 4891 structuring in the initializer, including the outermost one. It 4892 saves the values of most of the variables above. */ 4893 4894struct constructor_range_stack; 4895 4896struct constructor_stack 4897{ 4898 struct constructor_stack *next; 4899 tree type; 4900 tree fields; 4901 tree index; 4902 tree max_index; 4903 tree unfilled_index; 4904 tree unfilled_fields; 4905 tree bit_index; 4906 VEC(constructor_elt,gc) *elements; 4907 struct init_node *pending_elts; 4908 int offset; 4909 int depth; 4910 /* If value nonzero, this value should replace the entire 4911 constructor at this level. */ 4912 struct c_expr replacement_value; 4913 struct constructor_range_stack *range_stack; 4914 char constant; 4915 char simple; 4916 char implicit; 4917 char erroneous; 4918 char outer; 4919 char incremental; 4920 char designated; 4921}; 4922 4923static struct constructor_stack *constructor_stack; 4924 4925/* This stack represents designators from some range designator up to 4926 the last designator in the list. */ 4927 4928struct constructor_range_stack 4929{ 4930 struct constructor_range_stack *next, *prev; 4931 struct constructor_stack *stack; 4932 tree range_start; 4933 tree index; 4934 tree range_end; 4935 tree fields; 4936}; 4937 4938static struct constructor_range_stack *constructor_range_stack; 4939 4940/* This stack records separate initializers that are nested. 4941 Nested initializers can't happen in ANSI C, but GNU C allows them 4942 in cases like { ... (struct foo) { ... } ... }. */ 4943 4944struct initializer_stack 4945{ 4946 struct initializer_stack *next; 4947 tree decl; 4948 struct constructor_stack *constructor_stack; 4949 struct constructor_range_stack *constructor_range_stack; 4950 VEC(constructor_elt,gc) *elements; 4951 struct spelling *spelling; 4952 struct spelling *spelling_base; 4953 int spelling_size; 4954 char top_level; 4955 char require_constant_value; 4956 char require_constant_elements; 4957}; 4958 4959static struct initializer_stack *initializer_stack; 4960 4961/* Prepare to parse and output the initializer for variable DECL. */ 4962 4963void 4964start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level) 4965{ 4966 const char *locus; 4967 struct initializer_stack *p = XNEW (struct initializer_stack); 4968 4969 p->decl = constructor_decl; 4970 p->require_constant_value = require_constant_value; 4971 p->require_constant_elements = require_constant_elements; 4972 p->constructor_stack = constructor_stack; 4973 p->constructor_range_stack = constructor_range_stack; 4974 p->elements = constructor_elements; 4975 p->spelling = spelling; 4976 p->spelling_base = spelling_base; 4977 p->spelling_size = spelling_size; 4978 p->top_level = constructor_top_level; 4979 p->next = initializer_stack; 4980 initializer_stack = p; 4981 4982 constructor_decl = decl; 4983 constructor_designated = 0; 4984 constructor_top_level = top_level; 4985 4986 if (decl != 0 && decl != error_mark_node) 4987 { 4988 require_constant_value = TREE_STATIC (decl); 4989 require_constant_elements 4990 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99)) 4991 /* For a scalar, you can always use any value to initialize, 4992 even within braces. */ 4993 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE 4994 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE 4995 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE 4996 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE)); 4997 locus = IDENTIFIER_POINTER (DECL_NAME (decl)); 4998 } 4999 else 5000 { 5001 require_constant_value = 0; 5002 require_constant_elements = 0; 5003 locus = "(anonymous)"; 5004 } 5005 5006 constructor_stack = 0; 5007 constructor_range_stack = 0; 5008 5009 missing_braces_mentioned = 0; 5010 5011 spelling_base = 0; 5012 spelling_size = 0; 5013 RESTORE_SPELLING_DEPTH (0); 5014 5015 if (locus) 5016 push_string (locus); 5017} 5018 5019void 5020finish_init (void) 5021{ 5022 struct initializer_stack *p = initializer_stack; 5023 5024 /* Free the whole constructor stack of this initializer. */ 5025 while (constructor_stack) 5026 { 5027 struct constructor_stack *q = constructor_stack; 5028 constructor_stack = q->next; 5029 free (q); 5030 } 5031 5032 gcc_assert (!constructor_range_stack); 5033 5034 /* Pop back to the data of the outer initializer (if any). */ 5035 free (spelling_base); 5036 5037 constructor_decl = p->decl; 5038 require_constant_value = p->require_constant_value; 5039 require_constant_elements = p->require_constant_elements; 5040 constructor_stack = p->constructor_stack; 5041 constructor_range_stack = p->constructor_range_stack; 5042 constructor_elements = p->elements; 5043 spelling = p->spelling; 5044 spelling_base = p->spelling_base; 5045 spelling_size = p->spelling_size; 5046 constructor_top_level = p->top_level; 5047 initializer_stack = p->next; 5048 free (p); 5049} 5050 5051/* Call here when we see the initializer is surrounded by braces. 5052 This is instead of a call to push_init_level; 5053 it is matched by a call to pop_init_level. 5054 5055 TYPE is the type to initialize, for a constructor expression. 5056 For an initializer for a decl, TYPE is zero. */ 5057 5058void 5059really_start_incremental_init (tree type) 5060{ 5061 struct constructor_stack *p = XNEW (struct constructor_stack); 5062 5063 if (type == 0) 5064 type = TREE_TYPE (constructor_decl); 5065 5066 if (targetm.vector_opaque_p (type)) 5067 error ("opaque vector types cannot be initialized"); 5068 5069 p->type = constructor_type; 5070 p->fields = constructor_fields; 5071 p->index = constructor_index; 5072 p->max_index = constructor_max_index; 5073 p->unfilled_index = constructor_unfilled_index; 5074 p->unfilled_fields = constructor_unfilled_fields; 5075 p->bit_index = constructor_bit_index; 5076 p->elements = constructor_elements; 5077 p->constant = constructor_constant; 5078 p->simple = constructor_simple; 5079 p->erroneous = constructor_erroneous; 5080 p->pending_elts = constructor_pending_elts; 5081 p->depth = constructor_depth; 5082 p->replacement_value.value = 0; 5083 p->replacement_value.original_code = ERROR_MARK; 5084 p->implicit = 0; 5085 p->range_stack = 0; 5086 p->outer = 0; 5087 p->incremental = constructor_incremental; 5088 p->designated = constructor_designated; 5089 p->next = 0; 5090 constructor_stack = p; 5091 5092 constructor_constant = 1; 5093 constructor_simple = 1; 5094 constructor_depth = SPELLING_DEPTH (); 5095 constructor_elements = 0; 5096 constructor_pending_elts = 0; 5097 constructor_type = type; 5098 constructor_incremental = 1; 5099 constructor_designated = 0; 5100 designator_depth = 0; 5101 designator_erroneous = 0; 5102 5103 if (TREE_CODE (constructor_type) == RECORD_TYPE 5104 || TREE_CODE (constructor_type) == UNION_TYPE) 5105 { 5106 constructor_fields = TYPE_FIELDS (constructor_type); 5107 /* Skip any nameless bit fields at the beginning. */ 5108 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields) 5109 && DECL_NAME (constructor_fields) == 0) 5110 constructor_fields = TREE_CHAIN (constructor_fields); 5111 5112 constructor_unfilled_fields = constructor_fields; 5113 constructor_bit_index = bitsize_zero_node; 5114 } 5115 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5116 { 5117 if (TYPE_DOMAIN (constructor_type)) 5118 { 5119 constructor_max_index 5120 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)); 5121 5122 /* Detect non-empty initializations of zero-length arrays. */ 5123 if (constructor_max_index == NULL_TREE 5124 && TYPE_SIZE (constructor_type)) 5125 constructor_max_index = build_int_cst (NULL_TREE, -1); 5126 5127 /* constructor_max_index needs to be an INTEGER_CST. Attempts 5128 to initialize VLAs will cause a proper error; avoid tree 5129 checking errors as well by setting a safe value. */ 5130 if (constructor_max_index 5131 && TREE_CODE (constructor_max_index) != INTEGER_CST) 5132 constructor_max_index = build_int_cst (NULL_TREE, -1); 5133 5134 constructor_index 5135 = convert (bitsizetype, 5136 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type))); 5137 } 5138 else 5139 { 5140 constructor_index = bitsize_zero_node; 5141 constructor_max_index = NULL_TREE; 5142 } 5143 5144 constructor_unfilled_index = constructor_index; 5145 } 5146 else if (TREE_CODE (constructor_type) == VECTOR_TYPE) 5147 { 5148 /* Vectors are like simple fixed-size arrays. */ 5149 constructor_max_index = 5150 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1); 5151 constructor_index = bitsize_zero_node; 5152 constructor_unfilled_index = constructor_index; 5153 } 5154 else 5155 { 5156 /* Handle the case of int x = {5}; */ 5157 constructor_fields = constructor_type; 5158 constructor_unfilled_fields = constructor_type; 5159 } 5160} 5161 5162/* Push down into a subobject, for initialization. 5163 If this is for an explicit set of braces, IMPLICIT is 0. 5164 If it is because the next element belongs at a lower level, 5165 IMPLICIT is 1 (or 2 if the push is because of designator list). */ 5166 5167void 5168push_init_level (int implicit) 5169{ 5170 struct constructor_stack *p; 5171 tree value = NULL_TREE; 5172 5173 /* If we've exhausted any levels that didn't have braces, 5174 pop them now. If implicit == 1, this will have been done in 5175 process_init_element; do not repeat it here because in the case 5176 of excess initializers for an empty aggregate this leads to an 5177 infinite cycle of popping a level and immediately recreating 5178 it. */ 5179 if (implicit != 1) 5180 { 5181 while (constructor_stack->implicit) 5182 { 5183 if ((TREE_CODE (constructor_type) == RECORD_TYPE 5184 || TREE_CODE (constructor_type) == UNION_TYPE) 5185 && constructor_fields == 0) 5186 process_init_element (pop_init_level (1)); 5187 else if (TREE_CODE (constructor_type) == ARRAY_TYPE 5188 && constructor_max_index 5189 && tree_int_cst_lt (constructor_max_index, 5190 constructor_index)) 5191 process_init_element (pop_init_level (1)); 5192 else 5193 break; 5194 } 5195 } 5196 5197 /* Unless this is an explicit brace, we need to preserve previous 5198 content if any. */ 5199 if (implicit) 5200 { 5201 if ((TREE_CODE (constructor_type) == RECORD_TYPE 5202 || TREE_CODE (constructor_type) == UNION_TYPE) 5203 && constructor_fields) 5204 value = find_init_member (constructor_fields); 5205 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5206 value = find_init_member (constructor_index); 5207 } 5208 5209 p = XNEW (struct constructor_stack); 5210 p->type = constructor_type; 5211 p->fields = constructor_fields; 5212 p->index = constructor_index; 5213 p->max_index = constructor_max_index; 5214 p->unfilled_index = constructor_unfilled_index; 5215 p->unfilled_fields = constructor_unfilled_fields; 5216 p->bit_index = constructor_bit_index; 5217 p->elements = constructor_elements; 5218 p->constant = constructor_constant; 5219 p->simple = constructor_simple; 5220 p->erroneous = constructor_erroneous; 5221 p->pending_elts = constructor_pending_elts; 5222 p->depth = constructor_depth; 5223 p->replacement_value.value = 0; 5224 p->replacement_value.original_code = ERROR_MARK; 5225 p->implicit = implicit; 5226 p->outer = 0; 5227 p->incremental = constructor_incremental; 5228 p->designated = constructor_designated; 5229 p->next = constructor_stack; 5230 p->range_stack = 0; 5231 constructor_stack = p; 5232 5233 constructor_constant = 1; 5234 constructor_simple = 1; 5235 constructor_depth = SPELLING_DEPTH (); 5236 constructor_elements = 0; 5237 constructor_incremental = 1; 5238 constructor_designated = 0; 5239 constructor_pending_elts = 0; 5240 if (!implicit) 5241 { 5242 p->range_stack = constructor_range_stack; 5243 constructor_range_stack = 0; 5244 designator_depth = 0; 5245 designator_erroneous = 0; 5246 } 5247 5248 /* Don't die if an entire brace-pair level is superfluous 5249 in the containing level. */ 5250 if (constructor_type == 0) 5251 ; 5252 else if (TREE_CODE (constructor_type) == RECORD_TYPE 5253 || TREE_CODE (constructor_type) == UNION_TYPE) 5254 { 5255 /* Don't die if there are extra init elts at the end. */ 5256 if (constructor_fields == 0) 5257 constructor_type = 0; 5258 else 5259 { 5260 constructor_type = TREE_TYPE (constructor_fields); 5261 push_member_name (constructor_fields); 5262 constructor_depth++; 5263 } 5264 } 5265 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5266 { 5267 constructor_type = TREE_TYPE (constructor_type); 5268 push_array_bounds (tree_low_cst (constructor_index, 1)); 5269 constructor_depth++; 5270 } 5271 5272 if (constructor_type == 0) 5273 { 5274 error_init ("extra brace group at end of initializer"); 5275 constructor_fields = 0; 5276 constructor_unfilled_fields = 0; 5277 return; 5278 } 5279 5280 if (value && TREE_CODE (value) == CONSTRUCTOR) 5281 { 5282 constructor_constant = TREE_CONSTANT (value); 5283 constructor_simple = TREE_STATIC (value); 5284 constructor_elements = CONSTRUCTOR_ELTS (value); 5285 if (!VEC_empty (constructor_elt, constructor_elements) 5286 && (TREE_CODE (constructor_type) == RECORD_TYPE 5287 || TREE_CODE (constructor_type) == ARRAY_TYPE)) 5288 set_nonincremental_init (); 5289 } 5290 5291 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned) 5292 { 5293 missing_braces_mentioned = 1; 5294 warning_init ("missing braces around initializer"); 5295 } 5296 5297 if (TREE_CODE (constructor_type) == RECORD_TYPE 5298 || TREE_CODE (constructor_type) == UNION_TYPE) 5299 { 5300 constructor_fields = TYPE_FIELDS (constructor_type); 5301 /* Skip any nameless bit fields at the beginning. */ 5302 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields) 5303 && DECL_NAME (constructor_fields) == 0) 5304 constructor_fields = TREE_CHAIN (constructor_fields); 5305 5306 constructor_unfilled_fields = constructor_fields; 5307 constructor_bit_index = bitsize_zero_node; 5308 } 5309 else if (TREE_CODE (constructor_type) == VECTOR_TYPE) 5310 { 5311 /* Vectors are like simple fixed-size arrays. */ 5312 constructor_max_index = 5313 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1); 5314 constructor_index = convert (bitsizetype, integer_zero_node); 5315 constructor_unfilled_index = constructor_index; 5316 } 5317 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5318 { 5319 if (TYPE_DOMAIN (constructor_type)) 5320 { 5321 constructor_max_index 5322 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)); 5323 5324 /* Detect non-empty initializations of zero-length arrays. */ 5325 if (constructor_max_index == NULL_TREE 5326 && TYPE_SIZE (constructor_type)) 5327 constructor_max_index = build_int_cst (NULL_TREE, -1); 5328 5329 /* constructor_max_index needs to be an INTEGER_CST. Attempts 5330 to initialize VLAs will cause a proper error; avoid tree 5331 checking errors as well by setting a safe value. */ 5332 if (constructor_max_index 5333 && TREE_CODE (constructor_max_index) != INTEGER_CST) 5334 constructor_max_index = build_int_cst (NULL_TREE, -1); 5335 5336 constructor_index 5337 = convert (bitsizetype, 5338 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type))); 5339 } 5340 else 5341 constructor_index = bitsize_zero_node; 5342 5343 constructor_unfilled_index = constructor_index; 5344 if (value && TREE_CODE (value) == STRING_CST) 5345 { 5346 /* We need to split the char/wchar array into individual 5347 characters, so that we don't have to special case it 5348 everywhere. */ 5349 set_nonincremental_init_from_string (value); 5350 } 5351 } 5352 else 5353 { 5354 if (constructor_type != error_mark_node) 5355 warning_init ("braces around scalar initializer"); 5356 constructor_fields = constructor_type; 5357 constructor_unfilled_fields = constructor_type; 5358 } 5359} 5360 5361/* At the end of an implicit or explicit brace level, 5362 finish up that level of constructor. If a single expression 5363 with redundant braces initialized that level, return the 5364 c_expr structure for that expression. Otherwise, the original_code 5365 element is set to ERROR_MARK. 5366 If we were outputting the elements as they are read, return 0 as the value 5367 from inner levels (process_init_element ignores that), 5368 but return error_mark_node as the value from the outermost level 5369 (that's what we want to put in DECL_INITIAL). 5370 Otherwise, return a CONSTRUCTOR expression as the value. */ 5371 5372struct c_expr 5373pop_init_level (int implicit) 5374{ 5375 struct constructor_stack *p; 5376 struct c_expr ret; 5377 ret.value = 0; 5378 ret.original_code = ERROR_MARK; 5379 5380 if (implicit == 0) 5381 { 5382 /* When we come to an explicit close brace, 5383 pop any inner levels that didn't have explicit braces. */ 5384 while (constructor_stack->implicit) 5385 process_init_element (pop_init_level (1)); 5386 5387 gcc_assert (!constructor_range_stack); 5388 } 5389 5390 /* Now output all pending elements. */ 5391 constructor_incremental = 1; 5392 output_pending_init_elements (1); 5393 5394 p = constructor_stack; 5395 5396 /* Error for initializing a flexible array member, or a zero-length 5397 array member in an inappropriate context. */ 5398 if (constructor_type && constructor_fields 5399 && TREE_CODE (constructor_type) == ARRAY_TYPE 5400 && TYPE_DOMAIN (constructor_type) 5401 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type))) 5402 { 5403 /* Silently discard empty initializations. The parser will 5404 already have pedwarned for empty brackets. */ 5405 if (integer_zerop (constructor_unfilled_index)) 5406 constructor_type = NULL_TREE; 5407 else 5408 { 5409 gcc_assert (!TYPE_SIZE (constructor_type)); 5410 5411 if (constructor_depth > 2) 5412 error_init ("initialization of flexible array member in a nested context"); 5413 else if (pedantic) 5414 pedwarn_init ("initialization of a flexible array member"); 5415 5416 /* We have already issued an error message for the existence 5417 of a flexible array member not at the end of the structure. 5418 Discard the initializer so that we do not die later. */ 5419 if (TREE_CHAIN (constructor_fields) != NULL_TREE) 5420 constructor_type = NULL_TREE; 5421 } 5422 } 5423 5424 /* Warn when some struct elements are implicitly initialized to zero. */ 5425 if (warn_missing_field_initializers 5426 && constructor_type 5427 && TREE_CODE (constructor_type) == RECORD_TYPE 5428 && constructor_unfilled_fields) 5429 { 5430 /* Do not warn for flexible array members or zero-length arrays. */ 5431 while (constructor_unfilled_fields 5432 && (!DECL_SIZE (constructor_unfilled_fields) 5433 || integer_zerop (DECL_SIZE (constructor_unfilled_fields)))) 5434 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields); 5435 5436 /* Do not warn if this level of the initializer uses member 5437 designators; it is likely to be deliberate. */ 5438 if (constructor_unfilled_fields && !constructor_designated) 5439 { 5440 push_member_name (constructor_unfilled_fields); 5441 warning_init ("missing initializer"); 5442 RESTORE_SPELLING_DEPTH (constructor_depth); 5443 } 5444 } 5445 5446 /* Pad out the end of the structure. */ 5447 if (p->replacement_value.value) 5448 /* If this closes a superfluous brace pair, 5449 just pass out the element between them. */ 5450 ret = p->replacement_value; 5451 else if (constructor_type == 0) 5452 ; 5453 else if (TREE_CODE (constructor_type) != RECORD_TYPE 5454 && TREE_CODE (constructor_type) != UNION_TYPE 5455 && TREE_CODE (constructor_type) != ARRAY_TYPE 5456 && TREE_CODE (constructor_type) != VECTOR_TYPE) 5457 { 5458 /* A nonincremental scalar initializer--just return 5459 the element, after verifying there is just one. */ 5460 if (VEC_empty (constructor_elt,constructor_elements)) 5461 { 5462 if (!constructor_erroneous) 5463 error_init ("empty scalar initializer"); 5464 ret.value = error_mark_node; 5465 } 5466 else if (VEC_length (constructor_elt,constructor_elements) != 1) 5467 { 5468 error_init ("extra elements in scalar initializer"); 5469 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value; 5470 } 5471 else 5472 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value; 5473 } 5474 else 5475 { 5476 if (constructor_erroneous) 5477 ret.value = error_mark_node; 5478 else 5479 { 5480 ret.value = build_constructor (constructor_type, 5481 constructor_elements); 5482 if (constructor_constant) 5483 TREE_CONSTANT (ret.value) = TREE_INVARIANT (ret.value) = 1; 5484 if (constructor_constant && constructor_simple) 5485 TREE_STATIC (ret.value) = 1; 5486 } 5487 } 5488 5489 constructor_type = p->type; 5490 constructor_fields = p->fields; 5491 constructor_index = p->index; 5492 constructor_max_index = p->max_index; 5493 constructor_unfilled_index = p->unfilled_index; 5494 constructor_unfilled_fields = p->unfilled_fields; 5495 constructor_bit_index = p->bit_index; 5496 constructor_elements = p->elements; 5497 constructor_constant = p->constant; 5498 constructor_simple = p->simple; 5499 constructor_erroneous = p->erroneous; 5500 constructor_incremental = p->incremental; 5501 constructor_designated = p->designated; 5502 constructor_pending_elts = p->pending_elts; 5503 constructor_depth = p->depth; 5504 if (!p->implicit) 5505 constructor_range_stack = p->range_stack; 5506 RESTORE_SPELLING_DEPTH (constructor_depth); 5507 5508 constructor_stack = p->next; 5509 free (p); 5510 5511 if (ret.value == 0 && constructor_stack == 0) 5512 ret.value = error_mark_node; 5513 return ret; 5514} 5515 5516/* Common handling for both array range and field name designators. 5517 ARRAY argument is nonzero for array ranges. Returns zero for success. */ 5518 5519static int 5520set_designator (int array) 5521{ 5522 tree subtype; 5523 enum tree_code subcode; 5524 5525 /* Don't die if an entire brace-pair level is superfluous 5526 in the containing level. */ 5527 if (constructor_type == 0) 5528 return 1; 5529 5530 /* If there were errors in this designator list already, bail out 5531 silently. */ 5532 if (designator_erroneous) 5533 return 1; 5534 5535 if (!designator_depth) 5536 { 5537 gcc_assert (!constructor_range_stack); 5538 5539 /* Designator list starts at the level of closest explicit 5540 braces. */ 5541 while (constructor_stack->implicit) 5542 process_init_element (pop_init_level (1)); 5543 constructor_designated = 1; 5544 return 0; 5545 } 5546 5547 switch (TREE_CODE (constructor_type)) 5548 { 5549 case RECORD_TYPE: 5550 case UNION_TYPE: 5551 subtype = TREE_TYPE (constructor_fields); 5552 if (subtype != error_mark_node) 5553 subtype = TYPE_MAIN_VARIANT (subtype); 5554 break; 5555 case ARRAY_TYPE: 5556 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type)); 5557 break; 5558 default: 5559 gcc_unreachable (); 5560 } 5561 5562 subcode = TREE_CODE (subtype); 5563 if (array && subcode != ARRAY_TYPE) 5564 { 5565 error_init ("array index in non-array initializer"); 5566 return 1; 5567 } 5568 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE) 5569 { 5570 error_init ("field name not in record or union initializer"); 5571 return 1; 5572 } 5573 5574 constructor_designated = 1; 5575 push_init_level (2); 5576 return 0; 5577} 5578 5579/* If there are range designators in designator list, push a new designator 5580 to constructor_range_stack. RANGE_END is end of such stack range or 5581 NULL_TREE if there is no range designator at this level. */ 5582 5583static void 5584push_range_stack (tree range_end) 5585{ 5586 struct constructor_range_stack *p; 5587 5588 p = GGC_NEW (struct constructor_range_stack); 5589 p->prev = constructor_range_stack; 5590 p->next = 0; 5591 p->fields = constructor_fields; 5592 p->range_start = constructor_index; 5593 p->index = constructor_index; 5594 p->stack = constructor_stack; 5595 p->range_end = range_end; 5596 if (constructor_range_stack) 5597 constructor_range_stack->next = p; 5598 constructor_range_stack = p; 5599} 5600 5601/* Within an array initializer, specify the next index to be initialized. 5602 FIRST is that index. If LAST is nonzero, then initialize a range 5603 of indices, running from FIRST through LAST. */ 5604 5605void 5606set_init_index (tree first, tree last) 5607{ 5608 if (set_designator (1)) 5609 return; 5610 5611 designator_erroneous = 1; 5612 5613 if (!INTEGRAL_TYPE_P (TREE_TYPE (first)) 5614 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last)))) 5615 { 5616 error_init ("array index in initializer not of integer type"); 5617 return; 5618 } 5619 5620 if (TREE_CODE (first) != INTEGER_CST) 5621 error_init ("nonconstant array index in initializer"); 5622 else if (last != 0 && TREE_CODE (last) != INTEGER_CST) 5623 error_init ("nonconstant array index in initializer"); 5624 else if (TREE_CODE (constructor_type) != ARRAY_TYPE) 5625 error_init ("array index in non-array initializer"); 5626 else if (tree_int_cst_sgn (first) == -1) 5627 error_init ("array index in initializer exceeds array bounds"); 5628 else if (constructor_max_index 5629 && tree_int_cst_lt (constructor_max_index, first)) 5630 error_init ("array index in initializer exceeds array bounds"); 5631 else 5632 { 5633 constructor_index = convert (bitsizetype, first); 5634 5635 if (last) 5636 { 5637 if (tree_int_cst_equal (first, last)) 5638 last = 0; 5639 else if (tree_int_cst_lt (last, first)) 5640 { 5641 error_init ("empty index range in initializer"); 5642 last = 0; 5643 } 5644 else 5645 { 5646 last = convert (bitsizetype, last); 5647 if (constructor_max_index != 0 5648 && tree_int_cst_lt (constructor_max_index, last)) 5649 { 5650 error_init ("array index range in initializer exceeds array bounds"); 5651 last = 0; 5652 } 5653 } 5654 } 5655 5656 designator_depth++; 5657 designator_erroneous = 0; 5658 if (constructor_range_stack || last) 5659 push_range_stack (last); 5660 } 5661} 5662 5663/* Within a struct initializer, specify the next field to be initialized. */ 5664 5665void 5666set_init_label (tree fieldname) 5667{ 5668 tree tail; 5669 5670 if (set_designator (0)) 5671 return; 5672 5673 designator_erroneous = 1; 5674 5675 if (TREE_CODE (constructor_type) != RECORD_TYPE 5676 && TREE_CODE (constructor_type) != UNION_TYPE) 5677 { 5678 error_init ("field name not in record or union initializer"); 5679 return; 5680 } 5681 5682 for (tail = TYPE_FIELDS (constructor_type); tail; 5683 tail = TREE_CHAIN (tail)) 5684 { 5685 if (DECL_NAME (tail) == fieldname) 5686 break; 5687 } 5688 5689 if (tail == 0) 5690 error ("unknown field %qE specified in initializer", fieldname); 5691 else 5692 { 5693 constructor_fields = tail; 5694 designator_depth++; 5695 designator_erroneous = 0; 5696 if (constructor_range_stack) 5697 push_range_stack (NULL_TREE); 5698 } 5699} 5700 5701/* Add a new initializer to the tree of pending initializers. PURPOSE 5702 identifies the initializer, either array index or field in a structure. 5703 VALUE is the value of that index or field. */ 5704 5705static void 5706add_pending_init (tree purpose, tree value) 5707{ 5708 struct init_node *p, **q, *r; 5709 5710 q = &constructor_pending_elts; 5711 p = 0; 5712 5713 if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5714 { 5715 while (*q != 0) 5716 { 5717 p = *q; 5718 if (tree_int_cst_lt (purpose, p->purpose)) 5719 q = &p->left; 5720 else if (tree_int_cst_lt (p->purpose, purpose)) 5721 q = &p->right; 5722 else 5723 { 5724 if (TREE_SIDE_EFFECTS (p->value)) 5725 warning_init ("initialized field with side-effects overwritten"); 5726 else if (warn_override_init) 5727 warning_init ("initialized field overwritten"); 5728 p->value = value; 5729 return; 5730 } 5731 } 5732 } 5733 else 5734 { 5735 tree bitpos; 5736 5737 bitpos = bit_position (purpose); 5738 while (*q != NULL) 5739 { 5740 p = *q; 5741 if (tree_int_cst_lt (bitpos, bit_position (p->purpose))) 5742 q = &p->left; 5743 else if (p->purpose != purpose) 5744 q = &p->right; 5745 else 5746 { 5747 if (TREE_SIDE_EFFECTS (p->value)) 5748 warning_init ("initialized field with side-effects overwritten"); 5749 else if (warn_override_init) 5750 warning_init ("initialized field overwritten"); 5751 p->value = value; 5752 return; 5753 } 5754 } 5755 } 5756 5757 r = GGC_NEW (struct init_node); 5758 r->purpose = purpose; 5759 r->value = value; 5760 5761 *q = r; 5762 r->parent = p; 5763 r->left = 0; 5764 r->right = 0; 5765 r->balance = 0; 5766 5767 while (p) 5768 { 5769 struct init_node *s; 5770 5771 if (r == p->left) 5772 { 5773 if (p->balance == 0) 5774 p->balance = -1; 5775 else if (p->balance < 0) 5776 { 5777 if (r->balance < 0) 5778 { 5779 /* L rotation. */ 5780 p->left = r->right; 5781 if (p->left) 5782 p->left->parent = p; 5783 r->right = p; 5784 5785 p->balance = 0; 5786 r->balance = 0; 5787 5788 s = p->parent; 5789 p->parent = r; 5790 r->parent = s; 5791 if (s) 5792 { 5793 if (s->left == p) 5794 s->left = r; 5795 else 5796 s->right = r; 5797 } 5798 else 5799 constructor_pending_elts = r; 5800 } 5801 else 5802 { 5803 /* LR rotation. */ 5804 struct init_node *t = r->right; 5805 5806 r->right = t->left; 5807 if (r->right) 5808 r->right->parent = r; 5809 t->left = r; 5810 5811 p->left = t->right; 5812 if (p->left) 5813 p->left->parent = p; 5814 t->right = p; 5815 5816 p->balance = t->balance < 0; 5817 r->balance = -(t->balance > 0); 5818 t->balance = 0; 5819 5820 s = p->parent; 5821 p->parent = t; 5822 r->parent = t; 5823 t->parent = s; 5824 if (s) 5825 { 5826 if (s->left == p) 5827 s->left = t; 5828 else 5829 s->right = t; 5830 } 5831 else 5832 constructor_pending_elts = t; 5833 } 5834 break; 5835 } 5836 else 5837 { 5838 /* p->balance == +1; growth of left side balances the node. */ 5839 p->balance = 0; 5840 break; 5841 } 5842 } 5843 else /* r == p->right */ 5844 { 5845 if (p->balance == 0) 5846 /* Growth propagation from right side. */ 5847 p->balance++; 5848 else if (p->balance > 0) 5849 { 5850 if (r->balance > 0) 5851 { 5852 /* R rotation. */ 5853 p->right = r->left; 5854 if (p->right) 5855 p->right->parent = p; 5856 r->left = p; 5857 5858 p->balance = 0; 5859 r->balance = 0; 5860 5861 s = p->parent; 5862 p->parent = r; 5863 r->parent = s; 5864 if (s) 5865 { 5866 if (s->left == p) 5867 s->left = r; 5868 else 5869 s->right = r; 5870 } 5871 else 5872 constructor_pending_elts = r; 5873 } 5874 else /* r->balance == -1 */ 5875 { 5876 /* RL rotation */ 5877 struct init_node *t = r->left; 5878 5879 r->left = t->right; 5880 if (r->left) 5881 r->left->parent = r; 5882 t->right = r; 5883 5884 p->right = t->left; 5885 if (p->right) 5886 p->right->parent = p; 5887 t->left = p; 5888 5889 r->balance = (t->balance < 0); 5890 p->balance = -(t->balance > 0); 5891 t->balance = 0; 5892 5893 s = p->parent; 5894 p->parent = t; 5895 r->parent = t; 5896 t->parent = s; 5897 if (s) 5898 { 5899 if (s->left == p) 5900 s->left = t; 5901 else 5902 s->right = t; 5903 } 5904 else 5905 constructor_pending_elts = t; 5906 } 5907 break; 5908 } 5909 else 5910 { 5911 /* p->balance == -1; growth of right side balances the node. */ 5912 p->balance = 0; 5913 break; 5914 } 5915 } 5916 5917 r = p; 5918 p = p->parent; 5919 } 5920} 5921 5922/* Build AVL tree from a sorted chain. */ 5923 5924static void 5925set_nonincremental_init (void) 5926{ 5927 unsigned HOST_WIDE_INT ix; 5928 tree index, value; 5929 5930 if (TREE_CODE (constructor_type) != RECORD_TYPE 5931 && TREE_CODE (constructor_type) != ARRAY_TYPE) 5932 return; 5933 5934 FOR_EACH_CONSTRUCTOR_ELT (constructor_elements, ix, index, value) 5935 add_pending_init (index, value); 5936 constructor_elements = 0; 5937 if (TREE_CODE (constructor_type) == RECORD_TYPE) 5938 { 5939 constructor_unfilled_fields = TYPE_FIELDS (constructor_type); 5940 /* Skip any nameless bit fields at the beginning. */ 5941 while (constructor_unfilled_fields != 0 5942 && DECL_C_BIT_FIELD (constructor_unfilled_fields) 5943 && DECL_NAME (constructor_unfilled_fields) == 0) 5944 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields); 5945 5946 } 5947 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 5948 { 5949 if (TYPE_DOMAIN (constructor_type)) 5950 constructor_unfilled_index 5951 = convert (bitsizetype, 5952 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type))); 5953 else 5954 constructor_unfilled_index = bitsize_zero_node; 5955 } 5956 constructor_incremental = 0; 5957} 5958 5959/* Build AVL tree from a string constant. */ 5960 5961static void 5962set_nonincremental_init_from_string (tree str) 5963{ 5964 tree value, purpose, type; 5965 HOST_WIDE_INT val[2]; 5966 const char *p, *end; 5967 int byte, wchar_bytes, charwidth, bitpos; 5968 5969 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE); 5970 5971 if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str))) 5972 == TYPE_PRECISION (char_type_node)) 5973 wchar_bytes = 1; 5974 else 5975 { 5976 gcc_assert (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str))) 5977 == TYPE_PRECISION (wchar_type_node)); 5978 wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT; 5979 } 5980 charwidth = TYPE_PRECISION (char_type_node); 5981 type = TREE_TYPE (constructor_type); 5982 p = TREE_STRING_POINTER (str); 5983 end = p + TREE_STRING_LENGTH (str); 5984 5985 for (purpose = bitsize_zero_node; 5986 p < end && !tree_int_cst_lt (constructor_max_index, purpose); 5987 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node)) 5988 { 5989 if (wchar_bytes == 1) 5990 { 5991 val[1] = (unsigned char) *p++; 5992 val[0] = 0; 5993 } 5994 else 5995 { 5996 val[0] = 0; 5997 val[1] = 0; 5998 for (byte = 0; byte < wchar_bytes; byte++) 5999 { 6000 if (BYTES_BIG_ENDIAN) 6001 bitpos = (wchar_bytes - byte - 1) * charwidth; 6002 else 6003 bitpos = byte * charwidth; 6004 val[bitpos < HOST_BITS_PER_WIDE_INT] 6005 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++)) 6006 << (bitpos % HOST_BITS_PER_WIDE_INT); 6007 } 6008 } 6009 6010 if (!TYPE_UNSIGNED (type)) 6011 { 6012 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR; 6013 if (bitpos < HOST_BITS_PER_WIDE_INT) 6014 { 6015 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1))) 6016 { 6017 val[1] |= ((HOST_WIDE_INT) -1) << bitpos; 6018 val[0] = -1; 6019 } 6020 } 6021 else if (bitpos == HOST_BITS_PER_WIDE_INT) 6022 { 6023 if (val[1] < 0) 6024 val[0] = -1; 6025 } 6026 else if (val[0] & (((HOST_WIDE_INT) 1) 6027 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT))) 6028 val[0] |= ((HOST_WIDE_INT) -1) 6029 << (bitpos - HOST_BITS_PER_WIDE_INT); 6030 } 6031 6032 value = build_int_cst_wide (type, val[1], val[0]); 6033 add_pending_init (purpose, value); 6034 } 6035 6036 constructor_incremental = 0; 6037} 6038 6039/* Return value of FIELD in pending initializer or zero if the field was 6040 not initialized yet. */ 6041 6042static tree 6043find_init_member (tree field) 6044{ 6045 struct init_node *p; 6046 6047 if (TREE_CODE (constructor_type) == ARRAY_TYPE) 6048 { 6049 if (constructor_incremental 6050 && tree_int_cst_lt (field, constructor_unfilled_index)) 6051 set_nonincremental_init (); 6052 6053 p = constructor_pending_elts; 6054 while (p) 6055 { 6056 if (tree_int_cst_lt (field, p->purpose)) 6057 p = p->left; 6058 else if (tree_int_cst_lt (p->purpose, field)) 6059 p = p->right; 6060 else 6061 return p->value; 6062 } 6063 } 6064 else if (TREE_CODE (constructor_type) == RECORD_TYPE) 6065 { 6066 tree bitpos = bit_position (field); 6067 6068 if (constructor_incremental 6069 && (!constructor_unfilled_fields 6070 || tree_int_cst_lt (bitpos, 6071 bit_position (constructor_unfilled_fields)))) 6072 set_nonincremental_init (); 6073 6074 p = constructor_pending_elts; 6075 while (p) 6076 { 6077 if (field == p->purpose) 6078 return p->value; 6079 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose))) 6080 p = p->left; 6081 else 6082 p = p->right; 6083 } 6084 } 6085 else if (TREE_CODE (constructor_type) == UNION_TYPE) 6086 { 6087 if (!VEC_empty (constructor_elt, constructor_elements) 6088 && (VEC_last (constructor_elt, constructor_elements)->index 6089 == field)) 6090 return VEC_last (constructor_elt, constructor_elements)->value; 6091 } 6092 return 0; 6093} 6094 6095/* "Output" the next constructor element. 6096 At top level, really output it to assembler code now. 6097 Otherwise, collect it in a list from which we will make a CONSTRUCTOR. 6098 TYPE is the data type that the containing data type wants here. 6099 FIELD is the field (a FIELD_DECL) or the index that this element fills. 6100 If VALUE is a string constant, STRICT_STRING is true if it is 6101 unparenthesized or we should not warn here for it being parenthesized. 6102 For other types of VALUE, STRICT_STRING is not used. 6103 6104 PENDING if non-nil means output pending elements that belong 6105 right after this element. (PENDING is normally 1; 6106 it is 0 while outputting pending elements, to avoid recursion.) */ 6107 6108static void 6109output_init_element (tree value, bool strict_string, tree type, tree field, 6110 int pending) 6111{ 6112 constructor_elt *celt; 6113 6114 if (type == error_mark_node || value == error_mark_node) 6115 { 6116 constructor_erroneous = 1; 6117 return; 6118 } 6119 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE 6120 && (TREE_CODE (value) == STRING_CST 6121 || TREE_CODE (value) == COMPOUND_LITERAL_EXPR) 6122 && !(TREE_CODE (value) == STRING_CST 6123 && TREE_CODE (type) == ARRAY_TYPE 6124 && INTEGRAL_TYPE_P (TREE_TYPE (type))) 6125 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)), 6126 TYPE_MAIN_VARIANT (type))) 6127 value = array_to_pointer_conversion (value); 6128 6129 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR 6130 && require_constant_value && !flag_isoc99 && pending) 6131 { 6132 /* As an extension, allow initializing objects with static storage 6133 duration with compound literals (which are then treated just as 6134 the brace enclosed list they contain). */ 6135 tree decl = COMPOUND_LITERAL_EXPR_DECL (value); 6136 value = DECL_INITIAL (decl); 6137 } 6138 6139 if (value == error_mark_node) 6140 constructor_erroneous = 1; 6141 else if (!TREE_CONSTANT (value)) 6142 constructor_constant = 0; 6143 else if (!initializer_constant_valid_p (value, TREE_TYPE (value)) 6144 || ((TREE_CODE (constructor_type) == RECORD_TYPE 6145 || TREE_CODE (constructor_type) == UNION_TYPE) 6146 && DECL_C_BIT_FIELD (field) 6147 && TREE_CODE (value) != INTEGER_CST)) 6148 constructor_simple = 0; 6149 6150 if (!initializer_constant_valid_p (value, TREE_TYPE (value))) 6151 { 6152 if (require_constant_value) 6153 { 6154 error_init ("initializer element is not constant"); 6155 value = error_mark_node; 6156 } 6157 else if (require_constant_elements) 6158 pedwarn ("initializer element is not computable at load time"); 6159 } 6160 6161 /* If this field is empty (and not at the end of structure), 6162 don't do anything other than checking the initializer. */ 6163 if (field 6164 && (TREE_TYPE (field) == error_mark_node 6165 || (COMPLETE_TYPE_P (TREE_TYPE (field)) 6166 && integer_zerop (TYPE_SIZE (TREE_TYPE (field))) 6167 && (TREE_CODE (constructor_type) == ARRAY_TYPE 6168 || TREE_CHAIN (field))))) 6169 return; 6170 6171 value = digest_init (type, value, strict_string, require_constant_value); 6172 if (value == error_mark_node) 6173 { 6174 constructor_erroneous = 1; 6175 return; 6176 } 6177 6178 /* If this element doesn't come next in sequence, 6179 put it on constructor_pending_elts. */ 6180 if (TREE_CODE (constructor_type) == ARRAY_TYPE 6181 && (!constructor_incremental 6182 || !tree_int_cst_equal (field, constructor_unfilled_index))) 6183 { 6184 if (constructor_incremental 6185 && tree_int_cst_lt (field, constructor_unfilled_index)) 6186 set_nonincremental_init (); 6187 6188 add_pending_init (field, value); 6189 return; 6190 } 6191 else if (TREE_CODE (constructor_type) == RECORD_TYPE 6192 && (!constructor_incremental 6193 || field != constructor_unfilled_fields)) 6194 { 6195 /* We do this for records but not for unions. In a union, 6196 no matter which field is specified, it can be initialized 6197 right away since it starts at the beginning of the union. */ 6198 if (constructor_incremental) 6199 { 6200 if (!constructor_unfilled_fields) 6201 set_nonincremental_init (); 6202 else 6203 { 6204 tree bitpos, unfillpos; 6205 6206 bitpos = bit_position (field); 6207 unfillpos = bit_position (constructor_unfilled_fields); 6208 6209 if (tree_int_cst_lt (bitpos, unfillpos)) 6210 set_nonincremental_init (); 6211 } 6212 } 6213 6214 add_pending_init (field, value); 6215 return; 6216 } 6217 else if (TREE_CODE (constructor_type) == UNION_TYPE 6218 && !VEC_empty (constructor_elt, constructor_elements)) 6219 { 6220 if (TREE_SIDE_EFFECTS (VEC_last (constructor_elt, 6221 constructor_elements)->value)) 6222 warning_init ("initialized field with side-effects overwritten"); 6223 else if (warn_override_init) 6224 warning_init ("initialized field overwritten"); 6225 6226 /* We can have just one union field set. */ 6227 constructor_elements = 0; 6228 } 6229 6230 /* Otherwise, output this element either to 6231 constructor_elements or to the assembler file. */ 6232 6233 celt = VEC_safe_push (constructor_elt, gc, constructor_elements, NULL); 6234 celt->index = field; 6235 celt->value = value; 6236 6237 /* Advance the variable that indicates sequential elements output. */ 6238 if (TREE_CODE (constructor_type) == ARRAY_TYPE) 6239 constructor_unfilled_index 6240 = size_binop (PLUS_EXPR, constructor_unfilled_index, 6241 bitsize_one_node); 6242 else if (TREE_CODE (constructor_type) == RECORD_TYPE) 6243 { 6244 constructor_unfilled_fields 6245 = TREE_CHAIN (constructor_unfilled_fields); 6246 6247 /* Skip any nameless bit fields. */ 6248 while (constructor_unfilled_fields != 0 6249 && DECL_C_BIT_FIELD (constructor_unfilled_fields) 6250 && DECL_NAME (constructor_unfilled_fields) == 0) 6251 constructor_unfilled_fields = 6252 TREE_CHAIN (constructor_unfilled_fields); 6253 } 6254 else if (TREE_CODE (constructor_type) == UNION_TYPE) 6255 constructor_unfilled_fields = 0; 6256 6257 /* Now output any pending elements which have become next. */ 6258 if (pending) 6259 output_pending_init_elements (0); 6260} 6261 6262/* Output any pending elements which have become next. 6263 As we output elements, constructor_unfilled_{fields,index} 6264 advances, which may cause other elements to become next; 6265 if so, they too are output. 6266 6267 If ALL is 0, we return when there are 6268 no more pending elements to output now. 6269 6270 If ALL is 1, we output space as necessary so that 6271 we can output all the pending elements. */ 6272 6273static void 6274output_pending_init_elements (int all) 6275{ 6276 struct init_node *elt = constructor_pending_elts; 6277 tree next; 6278 6279 retry: 6280 6281 /* Look through the whole pending tree. 6282 If we find an element that should be output now, 6283 output it. Otherwise, set NEXT to the element 6284 that comes first among those still pending. */ 6285 6286 next = 0; 6287 while (elt) 6288 { 6289 if (TREE_CODE (constructor_type) == ARRAY_TYPE) 6290 { 6291 if (tree_int_cst_equal (elt->purpose, 6292 constructor_unfilled_index)) 6293 output_init_element (elt->value, true, 6294 TREE_TYPE (constructor_type), 6295 constructor_unfilled_index, 0); 6296 else if (tree_int_cst_lt (constructor_unfilled_index, 6297 elt->purpose)) 6298 { 6299 /* Advance to the next smaller node. */ 6300 if (elt->left) 6301 elt = elt->left; 6302 else 6303 { 6304 /* We have reached the smallest node bigger than the 6305 current unfilled index. Fill the space first. */ 6306 next = elt->purpose; 6307 break; 6308 } 6309 } 6310 else 6311 { 6312 /* Advance to the next bigger node. */ 6313 if (elt->right) 6314 elt = elt->right; 6315 else 6316 { 6317 /* We have reached the biggest node in a subtree. Find 6318 the parent of it, which is the next bigger node. */ 6319 while (elt->parent && elt->parent->right == elt) 6320 elt = elt->parent; 6321 elt = elt->parent; 6322 if (elt && tree_int_cst_lt (constructor_unfilled_index, 6323 elt->purpose)) 6324 { 6325 next = elt->purpose; 6326 break; 6327 } 6328 } 6329 } 6330 } 6331 else if (TREE_CODE (constructor_type) == RECORD_TYPE 6332 || TREE_CODE (constructor_type) == UNION_TYPE) 6333 { 6334 tree ctor_unfilled_bitpos, elt_bitpos; 6335 6336 /* If the current record is complete we are done. */ 6337 if (constructor_unfilled_fields == 0) 6338 break; 6339 6340 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields); 6341 elt_bitpos = bit_position (elt->purpose); 6342 /* We can't compare fields here because there might be empty 6343 fields in between. */ 6344 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos)) 6345 { 6346 constructor_unfilled_fields = elt->purpose; 6347 output_init_element (elt->value, true, TREE_TYPE (elt->purpose), 6348 elt->purpose, 0); 6349 } 6350 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos)) 6351 { 6352 /* Advance to the next smaller node. */ 6353 if (elt->left) 6354 elt = elt->left; 6355 else 6356 { 6357 /* We have reached the smallest node bigger than the 6358 current unfilled field. Fill the space first. */ 6359 next = elt->purpose; 6360 break; 6361 } 6362 } 6363 else 6364 { 6365 /* Advance to the next bigger node. */ 6366 if (elt->right) 6367 elt = elt->right; 6368 else 6369 { 6370 /* We have reached the biggest node in a subtree. Find 6371 the parent of it, which is the next bigger node. */ 6372 while (elt->parent && elt->parent->right == elt) 6373 elt = elt->parent; 6374 elt = elt->parent; 6375 if (elt 6376 && (tree_int_cst_lt (ctor_unfilled_bitpos, 6377 bit_position (elt->purpose)))) 6378 { 6379 next = elt->purpose; 6380 break; 6381 } 6382 } 6383 } 6384 } 6385 } 6386 6387 /* Ordinarily return, but not if we want to output all 6388 and there are elements left. */ 6389 if (!(all && next != 0)) 6390 return; 6391 6392 /* If it's not incremental, just skip over the gap, so that after 6393 jumping to retry we will output the next successive element. */ 6394 if (TREE_CODE (constructor_type) == RECORD_TYPE 6395 || TREE_CODE (constructor_type) == UNION_TYPE) 6396 constructor_unfilled_fields = next; 6397 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 6398 constructor_unfilled_index = next; 6399 6400 /* ELT now points to the node in the pending tree with the next 6401 initializer to output. */ 6402 goto retry; 6403} 6404 6405/* Add one non-braced element to the current constructor level. 6406 This adjusts the current position within the constructor's type. 6407 This may also start or terminate implicit levels 6408 to handle a partly-braced initializer. 6409 6410 Once this has found the correct level for the new element, 6411 it calls output_init_element. */ 6412 6413void 6414process_init_element (struct c_expr value) 6415{ 6416 tree orig_value = value.value; 6417 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST; 6418 bool strict_string = value.original_code == STRING_CST; 6419 6420 designator_depth = 0; 6421 designator_erroneous = 0; 6422 6423 /* Handle superfluous braces around string cst as in 6424 char x[] = {"foo"}; */ 6425 if (string_flag 6426 && constructor_type 6427 && TREE_CODE (constructor_type) == ARRAY_TYPE 6428 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type)) 6429 && integer_zerop (constructor_unfilled_index)) 6430 { 6431 if (constructor_stack->replacement_value.value) 6432 error_init ("excess elements in char array initializer"); 6433 constructor_stack->replacement_value = value; 6434 return; 6435 } 6436 6437 if (constructor_stack->replacement_value.value != 0) 6438 { 6439 error_init ("excess elements in struct initializer"); 6440 return; 6441 } 6442 6443 /* Ignore elements of a brace group if it is entirely superfluous 6444 and has already been diagnosed. */ 6445 if (constructor_type == 0) 6446 return; 6447 6448 /* If we've exhausted any levels that didn't have braces, 6449 pop them now. */ 6450 while (constructor_stack->implicit) 6451 { 6452 if ((TREE_CODE (constructor_type) == RECORD_TYPE 6453 || TREE_CODE (constructor_type) == UNION_TYPE) 6454 && constructor_fields == 0) 6455 process_init_element (pop_init_level (1)); 6456 else if (TREE_CODE (constructor_type) == ARRAY_TYPE 6457 && (constructor_max_index == 0 6458 || tree_int_cst_lt (constructor_max_index, 6459 constructor_index))) 6460 process_init_element (pop_init_level (1)); 6461 else 6462 break; 6463 } 6464 6465 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */ 6466 if (constructor_range_stack) 6467 { 6468 /* If value is a compound literal and we'll be just using its 6469 content, don't put it into a SAVE_EXPR. */ 6470 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR 6471 || !require_constant_value 6472 || flag_isoc99) 6473 value.value = save_expr (value.value); 6474 } 6475 6476 while (1) 6477 { 6478 if (TREE_CODE (constructor_type) == RECORD_TYPE) 6479 { 6480 tree fieldtype; 6481 enum tree_code fieldcode; 6482 6483 if (constructor_fields == 0) 6484 { 6485 pedwarn_init ("excess elements in struct initializer"); 6486 break; 6487 } 6488 6489 fieldtype = TREE_TYPE (constructor_fields); 6490 if (fieldtype != error_mark_node) 6491 fieldtype = TYPE_MAIN_VARIANT (fieldtype); 6492 fieldcode = TREE_CODE (fieldtype); 6493 6494 /* Error for non-static initialization of a flexible array member. */ 6495 if (fieldcode == ARRAY_TYPE 6496 && !require_constant_value 6497 && TYPE_SIZE (fieldtype) == NULL_TREE 6498 && TREE_CHAIN (constructor_fields) == NULL_TREE) 6499 { 6500 error_init ("non-static initialization of a flexible array member"); 6501 break; 6502 } 6503 6504 /* Accept a string constant to initialize a subarray. */ 6505 if (value.value != 0 6506 && fieldcode == ARRAY_TYPE 6507 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype)) 6508 && string_flag) 6509 value.value = orig_value; 6510 /* Otherwise, if we have come to a subaggregate, 6511 and we don't have an element of its type, push into it. */ 6512 else if (value.value != 0 6513 && value.value != error_mark_node 6514 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype 6515 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE 6516 || fieldcode == UNION_TYPE)) 6517 { 6518 push_init_level (1); 6519 continue; 6520 } 6521 6522 if (value.value) 6523 { 6524 push_member_name (constructor_fields); 6525 output_init_element (value.value, strict_string, 6526 fieldtype, constructor_fields, 1); 6527 RESTORE_SPELLING_DEPTH (constructor_depth); 6528 } 6529 else 6530 /* Do the bookkeeping for an element that was 6531 directly output as a constructor. */ 6532 { 6533 /* For a record, keep track of end position of last field. */ 6534 if (DECL_SIZE (constructor_fields)) 6535 constructor_bit_index 6536 = size_binop (PLUS_EXPR, 6537 bit_position (constructor_fields), 6538 DECL_SIZE (constructor_fields)); 6539 6540 /* If the current field was the first one not yet written out, 6541 it isn't now, so update. */ 6542 if (constructor_unfilled_fields == constructor_fields) 6543 { 6544 constructor_unfilled_fields = TREE_CHAIN (constructor_fields); 6545 /* Skip any nameless bit fields. */ 6546 while (constructor_unfilled_fields != 0 6547 && DECL_C_BIT_FIELD (constructor_unfilled_fields) 6548 && DECL_NAME (constructor_unfilled_fields) == 0) 6549 constructor_unfilled_fields = 6550 TREE_CHAIN (constructor_unfilled_fields); 6551 } 6552 } 6553 6554 constructor_fields = TREE_CHAIN (constructor_fields); 6555 /* Skip any nameless bit fields at the beginning. */ 6556 while (constructor_fields != 0 6557 && DECL_C_BIT_FIELD (constructor_fields) 6558 && DECL_NAME (constructor_fields) == 0) 6559 constructor_fields = TREE_CHAIN (constructor_fields); 6560 } 6561 else if (TREE_CODE (constructor_type) == UNION_TYPE) 6562 { 6563 tree fieldtype; 6564 enum tree_code fieldcode; 6565 6566 if (constructor_fields == 0) 6567 { 6568 pedwarn_init ("excess elements in union initializer"); 6569 break; 6570 } 6571 6572 fieldtype = TREE_TYPE (constructor_fields); 6573 if (fieldtype != error_mark_node) 6574 fieldtype = TYPE_MAIN_VARIANT (fieldtype); 6575 fieldcode = TREE_CODE (fieldtype); 6576 6577 /* Warn that traditional C rejects initialization of unions. 6578 We skip the warning if the value is zero. This is done 6579 under the assumption that the zero initializer in user 6580 code appears conditioned on e.g. __STDC__ to avoid 6581 "missing initializer" warnings and relies on default 6582 initialization to zero in the traditional C case. 6583 We also skip the warning if the initializer is designated, 6584 again on the assumption that this must be conditional on 6585 __STDC__ anyway (and we've already complained about the 6586 member-designator already). */ 6587 if (!in_system_header && !constructor_designated 6588 && !(value.value && (integer_zerop (value.value) 6589 || real_zerop (value.value)))) 6590 warning (OPT_Wtraditional, "traditional C rejects initialization " 6591 "of unions"); 6592 6593 /* Accept a string constant to initialize a subarray. */ 6594 if (value.value != 0 6595 && fieldcode == ARRAY_TYPE 6596 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype)) 6597 && string_flag) 6598 value.value = orig_value; 6599 /* Otherwise, if we have come to a subaggregate, 6600 and we don't have an element of its type, push into it. */ 6601 else if (value.value != 0 6602 && value.value != error_mark_node 6603 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype 6604 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE 6605 || fieldcode == UNION_TYPE)) 6606 { 6607 push_init_level (1); 6608 continue; 6609 } 6610 6611 if (value.value) 6612 { 6613 push_member_name (constructor_fields); 6614 output_init_element (value.value, strict_string, 6615 fieldtype, constructor_fields, 1); 6616 RESTORE_SPELLING_DEPTH (constructor_depth); 6617 } 6618 else 6619 /* Do the bookkeeping for an element that was 6620 directly output as a constructor. */ 6621 { 6622 constructor_bit_index = DECL_SIZE (constructor_fields); 6623 constructor_unfilled_fields = TREE_CHAIN (constructor_fields); 6624 } 6625 6626 constructor_fields = 0; 6627 } 6628 else if (TREE_CODE (constructor_type) == ARRAY_TYPE) 6629 { 6630 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type)); 6631 enum tree_code eltcode = TREE_CODE (elttype); 6632 6633 /* Accept a string constant to initialize a subarray. */ 6634 if (value.value != 0 6635 && eltcode == ARRAY_TYPE 6636 && INTEGRAL_TYPE_P (TREE_TYPE (elttype)) 6637 && string_flag) 6638 value.value = orig_value; 6639 /* Otherwise, if we have come to a subaggregate, 6640 and we don't have an element of its type, push into it. */ 6641 else if (value.value != 0 6642 && value.value != error_mark_node 6643 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype 6644 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE 6645 || eltcode == UNION_TYPE)) 6646 { 6647 push_init_level (1); 6648 continue; 6649 } 6650 6651 if (constructor_max_index != 0 6652 && (tree_int_cst_lt (constructor_max_index, constructor_index) 6653 || integer_all_onesp (constructor_max_index))) 6654 { 6655 pedwarn_init ("excess elements in array initializer"); 6656 break; 6657 } 6658 6659 /* Now output the actual element. */ 6660 if (value.value) 6661 { 6662 push_array_bounds (tree_low_cst (constructor_index, 1)); 6663 output_init_element (value.value, strict_string, 6664 elttype, constructor_index, 1); 6665 RESTORE_SPELLING_DEPTH (constructor_depth); 6666 } 6667 6668 constructor_index 6669 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node); 6670 6671 if (!value.value) 6672 /* If we are doing the bookkeeping for an element that was 6673 directly output as a constructor, we must update 6674 constructor_unfilled_index. */ 6675 constructor_unfilled_index = constructor_index; 6676 } 6677 else if (TREE_CODE (constructor_type) == VECTOR_TYPE) 6678 { 6679 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type)); 6680 6681 /* Do a basic check of initializer size. Note that vectors 6682 always have a fixed size derived from their type. */ 6683 if (tree_int_cst_lt (constructor_max_index, constructor_index)) 6684 { 6685 pedwarn_init ("excess elements in vector initializer"); 6686 break; 6687 } 6688 6689 /* Now output the actual element. */ 6690 if (value.value) 6691 output_init_element (value.value, strict_string, 6692 elttype, constructor_index, 1); 6693 6694 constructor_index 6695 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node); 6696 6697 if (!value.value) 6698 /* If we are doing the bookkeeping for an element that was 6699 directly output as a constructor, we must update 6700 constructor_unfilled_index. */ 6701 constructor_unfilled_index = constructor_index; 6702 } 6703 6704 /* Handle the sole element allowed in a braced initializer 6705 for a scalar variable. */ 6706 else if (constructor_type != error_mark_node 6707 && constructor_fields == 0) 6708 { 6709 pedwarn_init ("excess elements in scalar initializer"); 6710 break; 6711 } 6712 else 6713 { 6714 if (value.value) 6715 output_init_element (value.value, strict_string, 6716 constructor_type, NULL_TREE, 1); 6717 constructor_fields = 0; 6718 } 6719 6720 /* Handle range initializers either at this level or anywhere higher 6721 in the designator stack. */ 6722 if (constructor_range_stack) 6723 { 6724 struct constructor_range_stack *p, *range_stack; 6725 int finish = 0; 6726 6727 range_stack = constructor_range_stack; 6728 constructor_range_stack = 0; 6729 while (constructor_stack != range_stack->stack) 6730 { 6731 gcc_assert (constructor_stack->implicit); 6732 process_init_element (pop_init_level (1)); 6733 } 6734 for (p = range_stack; 6735 !p->range_end || tree_int_cst_equal (p->index, p->range_end); 6736 p = p->prev) 6737 { 6738 gcc_assert (constructor_stack->implicit); 6739 process_init_element (pop_init_level (1)); 6740 } 6741 6742 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node); 6743 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev) 6744 finish = 1; 6745 6746 while (1) 6747 { 6748 constructor_index = p->index; 6749 constructor_fields = p->fields; 6750 if (finish && p->range_end && p->index == p->range_start) 6751 { 6752 finish = 0; 6753 p->prev = 0; 6754 } 6755 p = p->next; 6756 if (!p) 6757 break; 6758 push_init_level (2); 6759 p->stack = constructor_stack; 6760 if (p->range_end && tree_int_cst_equal (p->index, p->range_end)) 6761 p->index = p->range_start; 6762 } 6763 6764 if (!finish) 6765 constructor_range_stack = range_stack; 6766 continue; 6767 } 6768 6769 break; 6770 } 6771 6772 constructor_range_stack = 0; 6773} 6774 6775/* Build a complete asm-statement, whose components are a CV_QUALIFIER 6776 (guaranteed to be 'volatile' or null) and ARGS (represented using 6777 an ASM_EXPR node). */ 6778tree 6779build_asm_stmt (tree cv_qualifier, tree args) 6780{ 6781 if (!ASM_VOLATILE_P (args) && cv_qualifier) 6782 ASM_VOLATILE_P (args) = 1; 6783 return add_stmt (args); 6784} 6785 6786/* Build an asm-expr, whose components are a STRING, some OUTPUTS, 6787 some INPUTS, and some CLOBBERS. The latter three may be NULL. 6788 SIMPLE indicates whether there was anything at all after the 6789 string in the asm expression -- asm("blah") and asm("blah" : ) 6790 are subtly different. We use a ASM_EXPR node to represent this. */ 6791tree 6792build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers, 6793 bool simple) 6794{ 6795 tree tail; 6796 tree args; 6797 int i; 6798 const char *constraint; 6799 const char **oconstraints; 6800 bool allows_mem, allows_reg, is_inout; 6801 int ninputs, noutputs; 6802 6803 ninputs = list_length (inputs); 6804 noutputs = list_length (outputs); 6805 oconstraints = (const char **) alloca (noutputs * sizeof (const char *)); 6806 6807 string = resolve_asm_operand_names (string, outputs, inputs); 6808 6809 /* Remove output conversions that change the type but not the mode. */ 6810 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail)) 6811 { 6812 tree output = TREE_VALUE (tail); 6813 6814 /* ??? Really, this should not be here. Users should be using a 6815 proper lvalue, dammit. But there's a long history of using casts 6816 in the output operands. In cases like longlong.h, this becomes a 6817 primitive form of typechecking -- if the cast can be removed, then 6818 the output operand had a type of the proper width; otherwise we'll 6819 get an error. Gross, but ... */ 6820 STRIP_NOPS (output); 6821 6822 if (!lvalue_or_else (output, lv_asm)) 6823 output = error_mark_node; 6824 6825 if (output != error_mark_node 6826 && (TREE_READONLY (output) 6827 || TYPE_READONLY (TREE_TYPE (output)) 6828 || ((TREE_CODE (TREE_TYPE (output)) == RECORD_TYPE 6829 || TREE_CODE (TREE_TYPE (output)) == UNION_TYPE) 6830 && C_TYPE_FIELDS_READONLY (TREE_TYPE (output))))) 6831 readonly_error (output, lv_asm); 6832 6833 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail))); 6834 oconstraints[i] = constraint; 6835 6836 if (parse_output_constraint (&constraint, i, ninputs, noutputs, 6837 &allows_mem, &allows_reg, &is_inout)) 6838 { 6839 /* If the operand is going to end up in memory, 6840 mark it addressable. */ 6841 if (!allows_reg && !c_mark_addressable (output)) 6842 output = error_mark_node; 6843 } 6844 else 6845 output = error_mark_node; 6846 6847 TREE_VALUE (tail) = output; 6848 } 6849 6850 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail)) 6851 { 6852 tree input; 6853 6854 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail))); 6855 input = TREE_VALUE (tail); 6856 6857 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0, 6858 oconstraints, &allows_mem, &allows_reg)) 6859 { 6860 /* If the operand is going to end up in memory, 6861 mark it addressable. */ 6862 if (!allows_reg && allows_mem) 6863 { 6864 /* Strip the nops as we allow this case. FIXME, this really 6865 should be rejected or made deprecated. */ 6866 STRIP_NOPS (input); 6867 if (!c_mark_addressable (input)) 6868 input = error_mark_node; 6869 } 6870 } 6871 else 6872 input = error_mark_node; 6873 6874 TREE_VALUE (tail) = input; 6875 } 6876 6877 args = build_stmt (ASM_EXPR, string, outputs, inputs, clobbers); 6878 6879 /* asm statements without outputs, including simple ones, are treated 6880 as volatile. */ 6881 ASM_INPUT_P (args) = simple; 6882 ASM_VOLATILE_P (args) = (noutputs == 0); 6883 6884 return args; 6885} 6886 6887/* Generate a goto statement to LABEL. */ 6888 6889tree 6890c_finish_goto_label (tree label) 6891{ 6892 tree decl = lookup_label (label); 6893 if (!decl) 6894 return NULL_TREE; 6895 6896 if (C_DECL_UNJUMPABLE_STMT_EXPR (decl)) 6897 { 6898 error ("jump into statement expression"); 6899 return NULL_TREE; 6900 } 6901 6902 if (C_DECL_UNJUMPABLE_VM (decl)) 6903 { 6904 error ("jump into scope of identifier with variably modified type"); 6905 return NULL_TREE; 6906 } 6907 6908 if (!C_DECL_UNDEFINABLE_STMT_EXPR (decl)) 6909 { 6910 /* No jump from outside this statement expression context, so 6911 record that there is a jump from within this context. */ 6912 struct c_label_list *nlist; 6913 nlist = XOBNEW (&parser_obstack, struct c_label_list); 6914 nlist->next = label_context_stack_se->labels_used; 6915 nlist->label = decl; 6916 label_context_stack_se->labels_used = nlist; 6917 } 6918 6919 if (!C_DECL_UNDEFINABLE_VM (decl)) 6920 { 6921 /* No jump from outside this context context of identifiers with 6922 variably modified type, so record that there is a jump from 6923 within this context. */ 6924 struct c_label_list *nlist; 6925 nlist = XOBNEW (&parser_obstack, struct c_label_list); 6926 nlist->next = label_context_stack_vm->labels_used; 6927 nlist->label = decl; 6928 label_context_stack_vm->labels_used = nlist; 6929 } 6930 6931 TREE_USED (decl) = 1; 6932 return add_stmt (build1 (GOTO_EXPR, void_type_node, decl)); 6933} 6934 6935/* Generate a computed goto statement to EXPR. */ 6936 6937tree 6938c_finish_goto_ptr (tree expr) 6939{ 6940 if (pedantic) 6941 pedwarn ("ISO C forbids %<goto *expr;%>"); 6942 expr = convert (ptr_type_node, expr); 6943 return add_stmt (build1 (GOTO_EXPR, void_type_node, expr)); 6944} 6945 6946/* Generate a C `return' statement. RETVAL is the expression for what 6947 to return, or a null pointer for `return;' with no value. */ 6948 6949tree 6950c_finish_return (tree retval) 6951{ 6952 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl)), ret_stmt; 6953 bool no_warning = false; 6954 6955 if (TREE_THIS_VOLATILE (current_function_decl)) 6956 warning (0, "function declared %<noreturn%> has a %<return%> statement"); 6957 6958 if (!retval) 6959 { 6960 current_function_returns_null = 1; 6961 if ((warn_return_type || flag_isoc99) 6962 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE) 6963 { 6964 pedwarn_c99 ("%<return%> with no value, in " 6965 "function returning non-void"); 6966 no_warning = true; 6967 } 6968 } 6969 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE) 6970 { 6971 current_function_returns_null = 1; 6972 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE) 6973 pedwarn ("%<return%> with a value, in function returning void"); 6974 } 6975 else 6976 { 6977 tree t = convert_for_assignment (valtype, retval, ic_return, 6978 NULL_TREE, NULL_TREE, 0); 6979 tree res = DECL_RESULT (current_function_decl); 6980 tree inner; 6981 6982 current_function_returns_value = 1; 6983 if (t == error_mark_node) 6984 return NULL_TREE; 6985 6986 inner = t = convert (TREE_TYPE (res), t); 6987 6988 /* Strip any conversions, additions, and subtractions, and see if 6989 we are returning the address of a local variable. Warn if so. */ 6990 while (1) 6991 { 6992 switch (TREE_CODE (inner)) 6993 { 6994 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR: 6995 case PLUS_EXPR: 6996 inner = TREE_OPERAND (inner, 0); 6997 continue; 6998 6999 case MINUS_EXPR: 7000 /* If the second operand of the MINUS_EXPR has a pointer 7001 type (or is converted from it), this may be valid, so 7002 don't give a warning. */ 7003 { 7004 tree op1 = TREE_OPERAND (inner, 1); 7005 7006 while (!POINTER_TYPE_P (TREE_TYPE (op1)) 7007 && (TREE_CODE (op1) == NOP_EXPR 7008 || TREE_CODE (op1) == NON_LVALUE_EXPR 7009 || TREE_CODE (op1) == CONVERT_EXPR)) 7010 op1 = TREE_OPERAND (op1, 0); 7011 7012 if (POINTER_TYPE_P (TREE_TYPE (op1))) 7013 break; 7014 7015 inner = TREE_OPERAND (inner, 0); 7016 continue; 7017 } 7018 7019 case ADDR_EXPR: 7020 inner = TREE_OPERAND (inner, 0); 7021 7022 while (REFERENCE_CLASS_P (inner) 7023 && TREE_CODE (inner) != INDIRECT_REF) 7024 inner = TREE_OPERAND (inner, 0); 7025 7026 if (DECL_P (inner) 7027 && !DECL_EXTERNAL (inner) 7028 && !TREE_STATIC (inner) 7029 && DECL_CONTEXT (inner) == current_function_decl) 7030 warning (0, "function returns address of local variable"); 7031 break; 7032 7033 default: 7034 break; 7035 } 7036 7037 break; 7038 } 7039 7040 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t); 7041 } 7042 7043 ret_stmt = build_stmt (RETURN_EXPR, retval); 7044 TREE_NO_WARNING (ret_stmt) |= no_warning; 7045 return add_stmt (ret_stmt); 7046} 7047 7048struct c_switch { 7049 /* The SWITCH_EXPR being built. */ 7050 tree switch_expr; 7051 7052 /* The original type of the testing expression, i.e. before the 7053 default conversion is applied. */ 7054 tree orig_type; 7055 7056 /* A splay-tree mapping the low element of a case range to the high 7057 element, or NULL_TREE if there is no high element. Used to 7058 determine whether or not a new case label duplicates an old case 7059 label. We need a tree, rather than simply a hash table, because 7060 of the GNU case range extension. */ 7061 splay_tree cases; 7062 7063 /* Number of nested statement expressions within this switch 7064 statement; if nonzero, case and default labels may not 7065 appear. */ 7066 unsigned int blocked_stmt_expr; 7067 7068 /* Scope of outermost declarations of identifiers with variably 7069 modified type within this switch statement; if nonzero, case and 7070 default labels may not appear. */ 7071 unsigned int blocked_vm; 7072 7073 /* The next node on the stack. */ 7074 struct c_switch *next; 7075}; 7076 7077/* A stack of the currently active switch statements. The innermost 7078 switch statement is on the top of the stack. There is no need to 7079 mark the stack for garbage collection because it is only active 7080 during the processing of the body of a function, and we never 7081 collect at that point. */ 7082 7083struct c_switch *c_switch_stack; 7084 7085/* Start a C switch statement, testing expression EXP. Return the new 7086 SWITCH_EXPR. */ 7087 7088tree 7089c_start_case (tree exp) 7090{ 7091 tree orig_type = error_mark_node; 7092 struct c_switch *cs; 7093 7094 if (exp != error_mark_node) 7095 { 7096 orig_type = TREE_TYPE (exp); 7097 7098 if (!INTEGRAL_TYPE_P (orig_type)) 7099 { 7100 if (orig_type != error_mark_node) 7101 { 7102 error ("switch quantity not an integer"); 7103 orig_type = error_mark_node; 7104 } 7105 exp = integer_zero_node; 7106 } 7107 else 7108 { 7109 tree type = TYPE_MAIN_VARIANT (orig_type); 7110 7111 if (!in_system_header 7112 && (type == long_integer_type_node 7113 || type == long_unsigned_type_node)) 7114 warning (OPT_Wtraditional, "%<long%> switch expression not " 7115 "converted to %<int%> in ISO C"); 7116 7117 exp = default_conversion (exp); 7118 } 7119 } 7120 7121 /* Add this new SWITCH_EXPR to the stack. */ 7122 cs = XNEW (struct c_switch); 7123 cs->switch_expr = build3 (SWITCH_EXPR, orig_type, exp, NULL_TREE, NULL_TREE); 7124 cs->orig_type = orig_type; 7125 cs->cases = splay_tree_new (case_compare, NULL, NULL); 7126 cs->blocked_stmt_expr = 0; 7127 cs->blocked_vm = 0; 7128 cs->next = c_switch_stack; 7129 c_switch_stack = cs; 7130 7131 return add_stmt (cs->switch_expr); 7132} 7133 7134/* Process a case label. */ 7135 7136tree 7137do_case (tree low_value, tree high_value) 7138{ 7139 tree label = NULL_TREE; 7140 7141 if (c_switch_stack && !c_switch_stack->blocked_stmt_expr 7142 && !c_switch_stack->blocked_vm) 7143 { 7144 label = c_add_case_label (c_switch_stack->cases, 7145 SWITCH_COND (c_switch_stack->switch_expr), 7146 c_switch_stack->orig_type, 7147 low_value, high_value); 7148 if (label == error_mark_node) 7149 label = NULL_TREE; 7150 } 7151 else if (c_switch_stack && c_switch_stack->blocked_stmt_expr) 7152 { 7153 if (low_value) 7154 error ("case label in statement expression not containing " 7155 "enclosing switch statement"); 7156 else 7157 error ("%<default%> label in statement expression not containing " 7158 "enclosing switch statement"); 7159 } 7160 else if (c_switch_stack && c_switch_stack->blocked_vm) 7161 { 7162 if (low_value) 7163 error ("case label in scope of identifier with variably modified " 7164 "type not containing enclosing switch statement"); 7165 else 7166 error ("%<default%> label in scope of identifier with variably " 7167 "modified type not containing enclosing switch statement"); 7168 } 7169 else if (low_value) 7170 error ("case label not within a switch statement"); 7171 else 7172 error ("%<default%> label not within a switch statement"); 7173 7174 return label; 7175} 7176 7177/* Finish the switch statement. */ 7178 7179void 7180c_finish_case (tree body) 7181{ 7182 struct c_switch *cs = c_switch_stack; 7183 location_t switch_location; 7184 7185 SWITCH_BODY (cs->switch_expr) = body; 7186 7187 /* We must not be within a statement expression nested in the switch 7188 at this point; we might, however, be within the scope of an 7189 identifier with variably modified type nested in the switch. */ 7190 gcc_assert (!cs->blocked_stmt_expr); 7191 7192 /* Emit warnings as needed. */ 7193 if (EXPR_HAS_LOCATION (cs->switch_expr)) 7194 switch_location = EXPR_LOCATION (cs->switch_expr); 7195 else 7196 switch_location = input_location; 7197 c_do_switch_warnings (cs->cases, switch_location, 7198 TREE_TYPE (cs->switch_expr), 7199 SWITCH_COND (cs->switch_expr)); 7200 7201 /* Pop the stack. */ 7202 c_switch_stack = cs->next; 7203 splay_tree_delete (cs->cases); 7204 XDELETE (cs); 7205} 7206 7207/* Emit an if statement. IF_LOCUS is the location of the 'if'. COND, 7208 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK 7209 may be null. NESTED_IF is true if THEN_BLOCK contains another IF 7210 statement, and was not surrounded with parenthesis. */ 7211 7212void 7213c_finish_if_stmt (location_t if_locus, tree cond, tree then_block, 7214 tree else_block, bool nested_if) 7215{ 7216 tree stmt; 7217 7218 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */ 7219 if (warn_parentheses && nested_if && else_block == NULL) 7220 { 7221 tree inner_if = then_block; 7222 7223 /* We know from the grammar productions that there is an IF nested 7224 within THEN_BLOCK. Due to labels and c99 conditional declarations, 7225 it might not be exactly THEN_BLOCK, but should be the last 7226 non-container statement within. */ 7227 while (1) 7228 switch (TREE_CODE (inner_if)) 7229 { 7230 case COND_EXPR: 7231 goto found; 7232 case BIND_EXPR: 7233 inner_if = BIND_EXPR_BODY (inner_if); 7234 break; 7235 case STATEMENT_LIST: 7236 inner_if = expr_last (then_block); 7237 break; 7238 case TRY_FINALLY_EXPR: 7239 case TRY_CATCH_EXPR: 7240 inner_if = TREE_OPERAND (inner_if, 0); 7241 break; 7242 default: 7243 gcc_unreachable (); 7244 } 7245 found: 7246 7247 if (COND_EXPR_ELSE (inner_if)) 7248 warning (OPT_Wparentheses, 7249 "%Hsuggest explicit braces to avoid ambiguous %<else%>", 7250 &if_locus); 7251 } 7252 7253 empty_body_warning (then_block, else_block); 7254 7255 stmt = build3 (COND_EXPR, void_type_node, cond, then_block, else_block); 7256 SET_EXPR_LOCATION (stmt, if_locus); 7257 add_stmt (stmt); 7258} 7259 7260/* APPLE LOCAL begin for-fsf-4_4 3274130 5295549 */ \ 7261/* Emit a general-purpose loop construct. START_LOCUS is the location 7262 of the beginning of the loop. COND is the loop condition. 7263 COND_IS_FIRST is false for DO loops. INCR is the FOR increment 7264 expression. BODY is the statement controlled by the loop. BLAB is 7265 the break label. CLAB is the continue label. ATTRS is the 7266 attributes associated with the loop, which at present are 7267 associated with the topmost label. Everything is allowed to be 7268 NULL. */ 7269 7270/* APPLE LOCAL end for-fsf-4_4 3274130 5295549 */ \ 7271void 7272c_finish_loop (location_t start_locus, tree cond, tree incr, tree body, 7273/* APPLE LOCAL begin for-fsf-4_4 3274130 5295549 */ \ 7274 tree blab, tree clab, tree attrs, bool cond_is_first) 7275/* APPLE LOCAL end for-fsf-4_4 3274130 5295549 */ \ 7276{ 7277 tree entry = NULL, exit = NULL, t; 7278 7279 /* If the condition is zero don't generate a loop construct. */ 7280 if (cond && integer_zerop (cond)) 7281 { 7282 if (cond_is_first) 7283 { 7284 t = build_and_jump (&blab); 7285 SET_EXPR_LOCATION (t, start_locus); 7286 add_stmt (t); 7287 } 7288 } 7289 else 7290 { 7291 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE); 7292 7293 /* If we have an exit condition, then we build an IF with gotos either 7294 out of the loop, or to the top of it. If there's no exit condition, 7295 then we just build a jump back to the top. */ 7296 exit = build_and_jump (&LABEL_EXPR_LABEL (top)); 7297 7298 if (cond && !integer_nonzerop (cond)) 7299 { 7300 /* Canonicalize the loop condition to the end. This means 7301 generating a branch to the loop condition. Reuse the 7302 continue label, if possible. */ 7303 if (cond_is_first) 7304 { 7305 if (incr || !clab) 7306 { 7307 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE); 7308 t = build_and_jump (&LABEL_EXPR_LABEL (entry)); 7309 } 7310 else 7311 t = build1 (GOTO_EXPR, void_type_node, clab); 7312 SET_EXPR_LOCATION (t, start_locus); 7313 add_stmt (t); 7314 } 7315 7316 t = build_and_jump (&blab); 7317 exit = fold_build3 (COND_EXPR, void_type_node, cond, exit, t); 7318 if (cond_is_first) 7319 SET_EXPR_LOCATION (exit, start_locus); 7320 else 7321 SET_EXPR_LOCATION (exit, input_location); 7322 } 7323 7324 add_stmt (top); 7325 } 7326 7327 if (body) 7328 add_stmt (body); 7329 if (clab) 7330 add_stmt (build1 (LABEL_EXPR, void_type_node, clab)); 7331 if (incr) 7332 add_stmt (incr); 7333 if (entry) 7334 add_stmt (entry); 7335 if (exit) 7336 add_stmt (exit); 7337 if (blab) 7338 add_stmt (build1 (LABEL_EXPR, void_type_node, blab)); 7339} 7340 7341tree 7342c_finish_bc_stmt (tree *label_p, bool is_break) 7343{ 7344 bool skip; 7345 tree label = *label_p; 7346 7347 /* In switch statements break is sometimes stylistically used after 7348 a return statement. This can lead to spurious warnings about 7349 control reaching the end of a non-void function when it is 7350 inlined. Note that we are calling block_may_fallthru with 7351 language specific tree nodes; this works because 7352 block_may_fallthru returns true when given something it does not 7353 understand. */ 7354 skip = !block_may_fallthru (cur_stmt_list); 7355 7356 if (!label) 7357 { 7358 if (!skip) 7359 *label_p = label = create_artificial_label (); 7360 } 7361 else if (TREE_CODE (label) == LABEL_DECL) 7362 ; 7363 else switch (TREE_INT_CST_LOW (label)) 7364 { 7365 case 0: 7366 if (is_break) 7367 error ("break statement not within loop or switch"); 7368 else 7369 error ("continue statement not within a loop"); 7370 return NULL_TREE; 7371 7372 case 1: 7373 gcc_assert (is_break); 7374 error ("break statement used with OpenMP for loop"); 7375 return NULL_TREE; 7376 7377 default: 7378 gcc_unreachable (); 7379 } 7380 7381 if (skip) 7382 return NULL_TREE; 7383 7384 return add_stmt (build1 (GOTO_EXPR, void_type_node, label)); 7385} 7386 7387/* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */ 7388 7389static void 7390emit_side_effect_warnings (tree expr) 7391{ 7392 if (expr == error_mark_node) 7393 ; 7394 else if (!TREE_SIDE_EFFECTS (expr)) 7395 { 7396 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr)) 7397 warning (0, "%Hstatement with no effect", 7398 EXPR_HAS_LOCATION (expr) ? EXPR_LOCUS (expr) : &input_location); 7399 } 7400 else if (warn_unused_value) 7401 warn_if_unused_value (expr, input_location); 7402} 7403 7404/* Process an expression as if it were a complete statement. Emit 7405 diagnostics, but do not call ADD_STMT. */ 7406 7407tree 7408c_process_expr_stmt (tree expr) 7409{ 7410 if (!expr) 7411 return NULL_TREE; 7412 7413 if (warn_sequence_point) 7414 verify_sequence_points (expr); 7415 7416 if (TREE_TYPE (expr) != error_mark_node 7417 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr)) 7418 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE) 7419 error ("expression statement has incomplete type"); 7420 7421 /* If we're not processing a statement expression, warn about unused values. 7422 Warnings for statement expressions will be emitted later, once we figure 7423 out which is the result. */ 7424 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list) 7425 && (extra_warnings || warn_unused_value)) 7426 emit_side_effect_warnings (expr); 7427 7428 /* If the expression is not of a type to which we cannot assign a line 7429 number, wrap the thing in a no-op NOP_EXPR. */ 7430 if (DECL_P (expr) || CONSTANT_CLASS_P (expr)) 7431 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr); 7432 7433 if (EXPR_P (expr)) 7434 SET_EXPR_LOCATION (expr, input_location); 7435 7436 return expr; 7437} 7438 7439/* Emit an expression as a statement. */ 7440 7441tree 7442c_finish_expr_stmt (tree expr) 7443{ 7444 if (expr) 7445 return add_stmt (c_process_expr_stmt (expr)); 7446 else 7447 return NULL; 7448} 7449 7450/* Do the opposite and emit a statement as an expression. To begin, 7451 create a new binding level and return it. */ 7452 7453tree 7454c_begin_stmt_expr (void) 7455{ 7456 tree ret; 7457 struct c_label_context_se *nstack; 7458 struct c_label_list *glist; 7459 7460 /* We must force a BLOCK for this level so that, if it is not expanded 7461 later, there is a way to turn off the entire subtree of blocks that 7462 are contained in it. */ 7463 keep_next_level (); 7464 ret = c_begin_compound_stmt (true); 7465 if (c_switch_stack) 7466 { 7467 c_switch_stack->blocked_stmt_expr++; 7468 gcc_assert (c_switch_stack->blocked_stmt_expr != 0); 7469 } 7470 for (glist = label_context_stack_se->labels_used; 7471 glist != NULL; 7472 glist = glist->next) 7473 { 7474 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 1; 7475 } 7476 nstack = XOBNEW (&parser_obstack, struct c_label_context_se); 7477 nstack->labels_def = NULL; 7478 nstack->labels_used = NULL; 7479 nstack->next = label_context_stack_se; 7480 label_context_stack_se = nstack; 7481 7482 /* Mark the current statement list as belonging to a statement list. */ 7483 STATEMENT_LIST_STMT_EXPR (ret) = 1; 7484 7485 return ret; 7486} 7487 7488tree 7489c_finish_stmt_expr (tree body) 7490{ 7491 tree last, type, tmp, val; 7492 tree *last_p; 7493 struct c_label_list *dlist, *glist, *glist_prev = NULL; 7494 7495 body = c_end_compound_stmt (body, true); 7496 if (c_switch_stack) 7497 { 7498 gcc_assert (c_switch_stack->blocked_stmt_expr != 0); 7499 c_switch_stack->blocked_stmt_expr--; 7500 } 7501 /* It is no longer possible to jump to labels defined within this 7502 statement expression. */ 7503 for (dlist = label_context_stack_se->labels_def; 7504 dlist != NULL; 7505 dlist = dlist->next) 7506 { 7507 C_DECL_UNJUMPABLE_STMT_EXPR (dlist->label) = 1; 7508 } 7509 /* It is again possible to define labels with a goto just outside 7510 this statement expression. */ 7511 for (glist = label_context_stack_se->next->labels_used; 7512 glist != NULL; 7513 glist = glist->next) 7514 { 7515 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 0; 7516 glist_prev = glist; 7517 } 7518 if (glist_prev != NULL) 7519 glist_prev->next = label_context_stack_se->labels_used; 7520 else 7521 label_context_stack_se->next->labels_used 7522 = label_context_stack_se->labels_used; 7523 label_context_stack_se = label_context_stack_se->next; 7524 7525 /* Locate the last statement in BODY. See c_end_compound_stmt 7526 about always returning a BIND_EXPR. */ 7527 last_p = &BIND_EXPR_BODY (body); 7528 last = BIND_EXPR_BODY (body); 7529 7530 continue_searching: 7531 if (TREE_CODE (last) == STATEMENT_LIST) 7532 { 7533 tree_stmt_iterator i; 7534 7535 /* This can happen with degenerate cases like ({ }). No value. */ 7536 if (!TREE_SIDE_EFFECTS (last)) 7537 return body; 7538 7539 /* If we're supposed to generate side effects warnings, process 7540 all of the statements except the last. */ 7541 if (extra_warnings || warn_unused_value) 7542 { 7543 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i)) 7544 emit_side_effect_warnings (tsi_stmt (i)); 7545 } 7546 else 7547 i = tsi_last (last); 7548 last_p = tsi_stmt_ptr (i); 7549 last = *last_p; 7550 } 7551 7552 /* If the end of the list is exception related, then the list was split 7553 by a call to push_cleanup. Continue searching. */ 7554 if (TREE_CODE (last) == TRY_FINALLY_EXPR 7555 || TREE_CODE (last) == TRY_CATCH_EXPR) 7556 { 7557 last_p = &TREE_OPERAND (last, 0); 7558 last = *last_p; 7559 goto continue_searching; 7560 } 7561 7562 /* In the case that the BIND_EXPR is not necessary, return the 7563 expression out from inside it. */ 7564 if (last == error_mark_node 7565 || (last == BIND_EXPR_BODY (body) 7566 && BIND_EXPR_VARS (body) == NULL)) 7567 { 7568 /* Do not warn if the return value of a statement expression is 7569 unused. */ 7570 if (EXPR_P (last)) 7571 TREE_NO_WARNING (last) = 1; 7572 return last; 7573 } 7574 7575 /* Extract the type of said expression. */ 7576 type = TREE_TYPE (last); 7577 7578 /* If we're not returning a value at all, then the BIND_EXPR that 7579 we already have is a fine expression to return. */ 7580 if (!type || VOID_TYPE_P (type)) 7581 return body; 7582 7583 /* Now that we've located the expression containing the value, it seems 7584 silly to make voidify_wrapper_expr repeat the process. Create a 7585 temporary of the appropriate type and stick it in a TARGET_EXPR. */ 7586 tmp = create_tmp_var_raw (type, NULL); 7587 7588 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids 7589 tree_expr_nonnegative_p giving up immediately. */ 7590 val = last; 7591 if (TREE_CODE (val) == NOP_EXPR 7592 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))) 7593 val = TREE_OPERAND (val, 0); 7594 7595 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val); 7596 SET_EXPR_LOCUS (*last_p, EXPR_LOCUS (last)); 7597 7598 return build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE); 7599} 7600 7601/* Begin the scope of an identifier of variably modified type, scope 7602 number SCOPE. Jumping from outside this scope to inside it is not 7603 permitted. */ 7604 7605void 7606c_begin_vm_scope (unsigned int scope) 7607{ 7608 struct c_label_context_vm *nstack; 7609 struct c_label_list *glist; 7610 7611 gcc_assert (scope > 0); 7612 7613 /* At file_scope, we don't have to do any processing. */ 7614 if (label_context_stack_vm == NULL) 7615 return; 7616 7617 if (c_switch_stack && !c_switch_stack->blocked_vm) 7618 c_switch_stack->blocked_vm = scope; 7619 for (glist = label_context_stack_vm->labels_used; 7620 glist != NULL; 7621 glist = glist->next) 7622 { 7623 C_DECL_UNDEFINABLE_VM (glist->label) = 1; 7624 } 7625 nstack = XOBNEW (&parser_obstack, struct c_label_context_vm); 7626 nstack->labels_def = NULL; 7627 nstack->labels_used = NULL; 7628 nstack->scope = scope; 7629 nstack->next = label_context_stack_vm; 7630 label_context_stack_vm = nstack; 7631} 7632 7633/* End a scope which may contain identifiers of variably modified 7634 type, scope number SCOPE. */ 7635 7636void 7637c_end_vm_scope (unsigned int scope) 7638{ 7639 if (label_context_stack_vm == NULL) 7640 return; 7641 if (c_switch_stack && c_switch_stack->blocked_vm == scope) 7642 c_switch_stack->blocked_vm = 0; 7643 /* We may have a number of nested scopes of identifiers with 7644 variably modified type, all at this depth. Pop each in turn. */ 7645 while (label_context_stack_vm->scope == scope) 7646 { 7647 struct c_label_list *dlist, *glist, *glist_prev = NULL; 7648 7649 /* It is no longer possible to jump to labels defined within this 7650 scope. */ 7651 for (dlist = label_context_stack_vm->labels_def; 7652 dlist != NULL; 7653 dlist = dlist->next) 7654 { 7655 C_DECL_UNJUMPABLE_VM (dlist->label) = 1; 7656 } 7657 /* It is again possible to define labels with a goto just outside 7658 this scope. */ 7659 for (glist = label_context_stack_vm->next->labels_used; 7660 glist != NULL; 7661 glist = glist->next) 7662 { 7663 C_DECL_UNDEFINABLE_VM (glist->label) = 0; 7664 glist_prev = glist; 7665 } 7666 if (glist_prev != NULL) 7667 glist_prev->next = label_context_stack_vm->labels_used; 7668 else 7669 label_context_stack_vm->next->labels_used 7670 = label_context_stack_vm->labels_used; 7671 label_context_stack_vm = label_context_stack_vm->next; 7672 } 7673} 7674 7675/* Begin and end compound statements. This is as simple as pushing 7676 and popping new statement lists from the tree. */ 7677 7678tree 7679c_begin_compound_stmt (bool do_scope) 7680{ 7681 tree stmt = push_stmt_list (); 7682 if (do_scope) 7683 push_scope (); 7684 return stmt; 7685} 7686 7687tree 7688c_end_compound_stmt (tree stmt, bool do_scope) 7689{ 7690 tree block = NULL; 7691 7692 if (do_scope) 7693 { 7694 if (c_dialect_objc ()) 7695 objc_clear_super_receiver (); 7696 block = pop_scope (); 7697 } 7698 7699 stmt = pop_stmt_list (stmt); 7700 stmt = c_build_bind_expr (block, stmt); 7701 7702 /* If this compound statement is nested immediately inside a statement 7703 expression, then force a BIND_EXPR to be created. Otherwise we'll 7704 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular, 7705 STATEMENT_LISTs merge, and thus we can lose track of what statement 7706 was really last. */ 7707 if (cur_stmt_list 7708 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list) 7709 && TREE_CODE (stmt) != BIND_EXPR) 7710 { 7711 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL); 7712 TREE_SIDE_EFFECTS (stmt) = 1; 7713 } 7714 7715 return stmt; 7716} 7717 7718/* Queue a cleanup. CLEANUP is an expression/statement to be executed 7719 when the current scope is exited. EH_ONLY is true when this is not 7720 meant to apply to normal control flow transfer. */ 7721 7722void 7723push_cleanup (tree ARG_UNUSED (decl), tree cleanup, bool eh_only) 7724{ 7725 enum tree_code code; 7726 tree stmt, list; 7727 bool stmt_expr; 7728 7729 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR; 7730 stmt = build_stmt (code, NULL, cleanup); 7731 add_stmt (stmt); 7732 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list); 7733 list = push_stmt_list (); 7734 TREE_OPERAND (stmt, 0) = list; 7735 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr; 7736} 7737 7738/* Build a binary-operation expression without default conversions. 7739 CODE is the kind of expression to build. 7740 This function differs from `build' in several ways: 7741 the data type of the result is computed and recorded in it, 7742 warnings are generated if arg data types are invalid, 7743 special handling for addition and subtraction of pointers is known, 7744 and some optimization is done (operations on narrow ints 7745 are done in the narrower type when that gives the same result). 7746 Constant folding is also done before the result is returned. 7747 7748 Note that the operands will never have enumeral types, or function 7749 or array types, because either they will have the default conversions 7750 performed or they have both just been converted to some other type in which 7751 the arithmetic is to be done. */ 7752 7753tree 7754build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1, 7755 int convert_p) 7756{ 7757 tree type0, type1; 7758 enum tree_code code0, code1; 7759 tree op0, op1; 7760 const char *invalid_op_diag; 7761 7762 /* Expression code to give to the expression when it is built. 7763 Normally this is CODE, which is what the caller asked for, 7764 but in some special cases we change it. */ 7765 enum tree_code resultcode = code; 7766 7767 /* Data type in which the computation is to be performed. 7768 In the simplest cases this is the common type of the arguments. */ 7769 tree result_type = NULL; 7770 7771 /* Nonzero means operands have already been type-converted 7772 in whatever way is necessary. 7773 Zero means they need to be converted to RESULT_TYPE. */ 7774 int converted = 0; 7775 7776 /* Nonzero means create the expression with this type, rather than 7777 RESULT_TYPE. */ 7778 tree build_type = 0; 7779 7780 /* Nonzero means after finally constructing the expression 7781 convert it to this type. */ 7782 tree final_type = 0; 7783 7784 /* Nonzero if this is an operation like MIN or MAX which can 7785 safely be computed in short if both args are promoted shorts. 7786 Also implies COMMON. 7787 -1 indicates a bitwise operation; this makes a difference 7788 in the exact conditions for when it is safe to do the operation 7789 in a narrower mode. */ 7790 int shorten = 0; 7791 7792 /* Nonzero if this is a comparison operation; 7793 if both args are promoted shorts, compare the original shorts. 7794 Also implies COMMON. */ 7795 int short_compare = 0; 7796 7797 /* Nonzero if this is a right-shift operation, which can be computed on the 7798 original short and then promoted if the operand is a promoted short. */ 7799 int short_shift = 0; 7800 7801 /* Nonzero means set RESULT_TYPE to the common type of the args. */ 7802 int common = 0; 7803 7804 /* True means types are compatible as far as ObjC is concerned. */ 7805 bool objc_ok; 7806 7807 if (convert_p) 7808 { 7809 op0 = default_conversion (orig_op0); 7810 op1 = default_conversion (orig_op1); 7811 } 7812 else 7813 { 7814 op0 = orig_op0; 7815 op1 = orig_op1; 7816 } 7817 7818 type0 = TREE_TYPE (op0); 7819 type1 = TREE_TYPE (op1); 7820 7821 /* The expression codes of the data types of the arguments tell us 7822 whether the arguments are integers, floating, pointers, etc. */ 7823 code0 = TREE_CODE (type0); 7824 code1 = TREE_CODE (type1); 7825 7826 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */ 7827 STRIP_TYPE_NOPS (op0); 7828 STRIP_TYPE_NOPS (op1); 7829 7830 /* If an error was already reported for one of the arguments, 7831 avoid reporting another error. */ 7832 7833 if (code0 == ERROR_MARK || code1 == ERROR_MARK) 7834 return error_mark_node; 7835 7836 if ((invalid_op_diag 7837 = targetm.invalid_binary_op (code, type0, type1))) 7838 { 7839 error (invalid_op_diag, ""); 7840 return error_mark_node; 7841 } 7842 7843 objc_ok = objc_compare_types (type0, type1, -3, NULL_TREE); 7844 7845 switch (code) 7846 { 7847 case PLUS_EXPR: 7848 /* Handle the pointer + int case. */ 7849 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) 7850 return pointer_int_sum (PLUS_EXPR, op0, op1); 7851 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE) 7852 return pointer_int_sum (PLUS_EXPR, op1, op0); 7853 else 7854 common = 1; 7855 break; 7856 7857 case MINUS_EXPR: 7858 /* Subtraction of two similar pointers. 7859 We must subtract them as integers, then divide by object size. */ 7860 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE 7861 && comp_target_types (type0, type1)) 7862 return pointer_diff (op0, op1); 7863 /* Handle pointer minus int. Just like pointer plus int. */ 7864 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) 7865 return pointer_int_sum (MINUS_EXPR, op0, op1); 7866 else 7867 common = 1; 7868 break; 7869 7870 case MULT_EXPR: 7871 common = 1; 7872 break; 7873 7874 case TRUNC_DIV_EXPR: 7875 case CEIL_DIV_EXPR: 7876 case FLOOR_DIV_EXPR: 7877 case ROUND_DIV_EXPR: 7878 case EXACT_DIV_EXPR: 7879 /* Floating point division by zero is a legitimate way to obtain 7880 infinities and NaNs. */ 7881 if (skip_evaluation == 0 && integer_zerop (op1)) 7882 warning (OPT_Wdiv_by_zero, "division by zero"); 7883 7884 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE 7885 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE) 7886 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE 7887 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)) 7888 { 7889 enum tree_code tcode0 = code0, tcode1 = code1; 7890 7891 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE) 7892 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0))); 7893 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE) 7894 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1))); 7895 7896 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE)) 7897 resultcode = RDIV_EXPR; 7898 else 7899 /* Although it would be tempting to shorten always here, that 7900 loses on some targets, since the modulo instruction is 7901 undefined if the quotient can't be represented in the 7902 computation mode. We shorten only if unsigned or if 7903 dividing by something we know != -1. */ 7904 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0)) 7905 || (TREE_CODE (op1) == INTEGER_CST 7906 && !integer_all_onesp (op1))); 7907 common = 1; 7908 } 7909 break; 7910 7911 case BIT_AND_EXPR: 7912 case BIT_IOR_EXPR: 7913 case BIT_XOR_EXPR: 7914 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) 7915 shorten = -1; 7916 else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE) 7917 common = 1; 7918 break; 7919 7920 case TRUNC_MOD_EXPR: 7921 case FLOOR_MOD_EXPR: 7922 if (skip_evaluation == 0 && integer_zerop (op1)) 7923 warning (OPT_Wdiv_by_zero, "division by zero"); 7924 7925 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) 7926 { 7927 /* Although it would be tempting to shorten always here, that loses 7928 on some targets, since the modulo instruction is undefined if the 7929 quotient can't be represented in the computation mode. We shorten 7930 only if unsigned or if dividing by something we know != -1. */ 7931 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0)) 7932 || (TREE_CODE (op1) == INTEGER_CST 7933 && !integer_all_onesp (op1))); 7934 common = 1; 7935 } 7936 break; 7937 7938 case TRUTH_ANDIF_EXPR: 7939 case TRUTH_ORIF_EXPR: 7940 case TRUTH_AND_EXPR: 7941 case TRUTH_OR_EXPR: 7942 case TRUTH_XOR_EXPR: 7943 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE 7944 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE) 7945 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE 7946 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE)) 7947 { 7948 /* Result of these operations is always an int, 7949 but that does not mean the operands should be 7950 converted to ints! */ 7951 result_type = integer_type_node; 7952 op0 = c_common_truthvalue_conversion (op0); 7953 op1 = c_common_truthvalue_conversion (op1); 7954 converted = 1; 7955 } 7956 break; 7957 7958 /* Shift operations: result has same type as first operand; 7959 always convert second operand to int. 7960 Also set SHORT_SHIFT if shifting rightward. */ 7961 7962 case RSHIFT_EXPR: 7963 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) 7964 { 7965 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0) 7966 { 7967 if (tree_int_cst_sgn (op1) < 0) 7968 warning (0, "right shift count is negative"); 7969 else 7970 { 7971 if (!integer_zerop (op1)) 7972 short_shift = 1; 7973 7974 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0) 7975 warning (0, "right shift count >= width of type"); 7976 } 7977 } 7978 7979 /* Use the type of the value to be shifted. */ 7980 result_type = type0; 7981 /* Convert the shift-count to an integer, regardless of size 7982 of value being shifted. */ 7983 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) 7984 op1 = convert (integer_type_node, op1); 7985 /* Avoid converting op1 to result_type later. */ 7986 converted = 1; 7987 } 7988 break; 7989 7990 case LSHIFT_EXPR: 7991 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) 7992 { 7993 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0) 7994 { 7995 if (tree_int_cst_sgn (op1) < 0) 7996 warning (0, "left shift count is negative"); 7997 7998 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0) 7999 warning (0, "left shift count >= width of type"); 8000 } 8001 8002 /* Use the type of the value to be shifted. */ 8003 result_type = type0; 8004 /* Convert the shift-count to an integer, regardless of size 8005 of value being shifted. */ 8006 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node) 8007 op1 = convert (integer_type_node, op1); 8008 /* Avoid converting op1 to result_type later. */ 8009 converted = 1; 8010 } 8011 break; 8012 8013 case EQ_EXPR: 8014 case NE_EXPR: 8015 if (code0 == REAL_TYPE || code1 == REAL_TYPE) 8016 warning (OPT_Wfloat_equal, 8017 "comparing floating point with == or != is unsafe"); 8018 /* Result of comparison is always int, 8019 but don't convert the args to int! */ 8020 build_type = integer_type_node; 8021 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE 8022 || code0 == COMPLEX_TYPE) 8023 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE 8024 || code1 == COMPLEX_TYPE)) 8025 short_compare = 1; 8026 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) 8027 { 8028 tree tt0 = TREE_TYPE (type0); 8029 tree tt1 = TREE_TYPE (type1); 8030 /* Anything compares with void *. void * compares with anything. 8031 Otherwise, the targets must be compatible 8032 and both must be object or both incomplete. */ 8033 if (comp_target_types (type0, type1)) 8034 result_type = common_pointer_type (type0, type1); 8035 else if (VOID_TYPE_P (tt0)) 8036 { 8037 /* op0 != orig_op0 detects the case of something 8038 whose value is 0 but which isn't a valid null ptr const. */ 8039 if (pedantic && !null_pointer_constant_p (orig_op0) 8040 && TREE_CODE (tt1) == FUNCTION_TYPE) 8041 pedwarn ("ISO C forbids comparison of %<void *%>" 8042 " with function pointer"); 8043 } 8044 else if (VOID_TYPE_P (tt1)) 8045 { 8046 if (pedantic && !null_pointer_constant_p (orig_op1) 8047 && TREE_CODE (tt0) == FUNCTION_TYPE) 8048 pedwarn ("ISO C forbids comparison of %<void *%>" 8049 " with function pointer"); 8050 } 8051 else 8052 /* Avoid warning about the volatile ObjC EH puts on decls. */ 8053 if (!objc_ok) 8054 pedwarn ("comparison of distinct pointer types lacks a cast"); 8055 8056 if (result_type == NULL_TREE) 8057 result_type = ptr_type_node; 8058 } 8059 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1)) 8060 { 8061 if (TREE_CODE (op0) == ADDR_EXPR 8062 && DECL_P (TREE_OPERAND (op0, 0)) 8063 && (TREE_CODE (TREE_OPERAND (op0, 0)) == PARM_DECL 8064 || TREE_CODE (TREE_OPERAND (op0, 0)) == LABEL_DECL 8065 || !DECL_WEAK (TREE_OPERAND (op0, 0)))) 8066 warning (OPT_Waddress, "the address of %qD will never be NULL", 8067 TREE_OPERAND (op0, 0)); 8068 result_type = type0; 8069 } 8070 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0)) 8071 { 8072 if (TREE_CODE (op1) == ADDR_EXPR 8073 && DECL_P (TREE_OPERAND (op1, 0)) 8074 && (TREE_CODE (TREE_OPERAND (op1, 0)) == PARM_DECL 8075 || TREE_CODE (TREE_OPERAND (op1, 0)) == LABEL_DECL 8076 || !DECL_WEAK (TREE_OPERAND (op1, 0)))) 8077 warning (OPT_Waddress, "the address of %qD will never be NULL", 8078 TREE_OPERAND (op1, 0)); 8079 result_type = type1; 8080 } 8081 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) 8082 { 8083 result_type = type0; 8084 pedwarn ("comparison between pointer and integer"); 8085 } 8086 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) 8087 { 8088 result_type = type1; 8089 pedwarn ("comparison between pointer and integer"); 8090 } 8091 break; 8092 8093 case LE_EXPR: 8094 case GE_EXPR: 8095 case LT_EXPR: 8096 case GT_EXPR: 8097 build_type = integer_type_node; 8098 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE) 8099 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE)) 8100 short_compare = 1; 8101 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE) 8102 { 8103 if (comp_target_types (type0, type1)) 8104 { 8105 result_type = common_pointer_type (type0, type1); 8106 if (!COMPLETE_TYPE_P (TREE_TYPE (type0)) 8107 != !COMPLETE_TYPE_P (TREE_TYPE (type1))) 8108 pedwarn ("comparison of complete and incomplete pointers"); 8109 else if (pedantic 8110 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE) 8111 pedwarn ("ISO C forbids ordered comparisons of pointers to functions"); 8112 } 8113 else 8114 { 8115 result_type = ptr_type_node; 8116 pedwarn ("comparison of distinct pointer types lacks a cast"); 8117 } 8118 } 8119 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1)) 8120 { 8121 result_type = type0; 8122 if (pedantic || extra_warnings) 8123 pedwarn ("ordered comparison of pointer with integer zero"); 8124 } 8125 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0)) 8126 { 8127 result_type = type1; 8128 if (pedantic) 8129 pedwarn ("ordered comparison of pointer with integer zero"); 8130 } 8131 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE) 8132 { 8133 result_type = type0; 8134 pedwarn ("comparison between pointer and integer"); 8135 } 8136 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE) 8137 { 8138 result_type = type1; 8139 pedwarn ("comparison between pointer and integer"); 8140 } 8141 break; 8142 8143 default: 8144 gcc_unreachable (); 8145 } 8146 8147 if (code0 == ERROR_MARK || code1 == ERROR_MARK) 8148 return error_mark_node; 8149 8150 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE 8151 && (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1)) 8152 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0), 8153 TREE_TYPE (type1)))) 8154 { 8155 binary_op_error (code, type0, type1); 8156 return error_mark_node; 8157 } 8158 8159 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE 8160 || code0 == VECTOR_TYPE) 8161 && 8162 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE 8163 || code1 == VECTOR_TYPE)) 8164 { 8165 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE); 8166 8167 if (shorten || common || short_compare) 8168 result_type = c_common_type (type0, type1); 8169 8170 /* For certain operations (which identify themselves by shorten != 0) 8171 if both args were extended from the same smaller type, 8172 do the arithmetic in that type and then extend. 8173 8174 shorten !=0 and !=1 indicates a bitwise operation. 8175 For them, this optimization is safe only if 8176 both args are zero-extended or both are sign-extended. 8177 Otherwise, we might change the result. 8178 Eg, (short)-1 | (unsigned short)-1 is (int)-1 8179 but calculated in (unsigned short) it would be (unsigned short)-1. */ 8180 8181 if (shorten && none_complex) 8182 { 8183 int unsigned0, unsigned1; 8184 tree arg0, arg1; 8185 int uns; 8186 tree type; 8187 8188 /* Cast OP0 and OP1 to RESULT_TYPE. Doing so prevents 8189 excessive narrowing when we call get_narrower below. For 8190 example, suppose that OP0 is of unsigned int extended 8191 from signed char and that RESULT_TYPE is long long int. 8192 If we explicitly cast OP0 to RESULT_TYPE, OP0 would look 8193 like 8194 8195 (long long int) (unsigned int) signed_char 8196 8197 which get_narrower would narrow down to 8198 8199 (unsigned int) signed char 8200 8201 If we do not cast OP0 first, get_narrower would return 8202 signed_char, which is inconsistent with the case of the 8203 explicit cast. */ 8204 op0 = convert (result_type, op0); 8205 op1 = convert (result_type, op1); 8206 8207 arg0 = get_narrower (op0, &unsigned0); 8208 arg1 = get_narrower (op1, &unsigned1); 8209 8210 /* UNS is 1 if the operation to be done is an unsigned one. */ 8211 uns = TYPE_UNSIGNED (result_type); 8212 8213 final_type = result_type; 8214 8215 /* Handle the case that OP0 (or OP1) does not *contain* a conversion 8216 but it *requires* conversion to FINAL_TYPE. */ 8217 8218 if ((TYPE_PRECISION (TREE_TYPE (op0)) 8219 == TYPE_PRECISION (TREE_TYPE (arg0))) 8220 && TREE_TYPE (op0) != final_type) 8221 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0)); 8222 if ((TYPE_PRECISION (TREE_TYPE (op1)) 8223 == TYPE_PRECISION (TREE_TYPE (arg1))) 8224 && TREE_TYPE (op1) != final_type) 8225 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1)); 8226 8227 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */ 8228 8229 /* For bitwise operations, signedness of nominal type 8230 does not matter. Consider only how operands were extended. */ 8231 if (shorten == -1) 8232 uns = unsigned0; 8233 8234 /* Note that in all three cases below we refrain from optimizing 8235 an unsigned operation on sign-extended args. 8236 That would not be valid. */ 8237 8238 /* Both args variable: if both extended in same way 8239 from same width, do it in that width. 8240 Do it unsigned if args were zero-extended. */ 8241 if ((TYPE_PRECISION (TREE_TYPE (arg0)) 8242 < TYPE_PRECISION (result_type)) 8243 && (TYPE_PRECISION (TREE_TYPE (arg1)) 8244 == TYPE_PRECISION (TREE_TYPE (arg0))) 8245 && unsigned0 == unsigned1 8246 && (unsigned0 || !uns)) 8247 result_type 8248 = c_common_signed_or_unsigned_type 8249 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1))); 8250 else if (TREE_CODE (arg0) == INTEGER_CST 8251 && (unsigned1 || !uns) 8252 && (TYPE_PRECISION (TREE_TYPE (arg1)) 8253 < TYPE_PRECISION (result_type)) 8254 && (type 8255 = c_common_signed_or_unsigned_type (unsigned1, 8256 TREE_TYPE (arg1)), 8257 int_fits_type_p (arg0, type))) 8258 result_type = type; 8259 else if (TREE_CODE (arg1) == INTEGER_CST 8260 && (unsigned0 || !uns) 8261 && (TYPE_PRECISION (TREE_TYPE (arg0)) 8262 < TYPE_PRECISION (result_type)) 8263 && (type 8264 = c_common_signed_or_unsigned_type (unsigned0, 8265 TREE_TYPE (arg0)), 8266 int_fits_type_p (arg1, type))) 8267 result_type = type; 8268 } 8269 8270 /* Shifts can be shortened if shifting right. */ 8271 8272 if (short_shift) 8273 { 8274 int unsigned_arg; 8275 tree arg0 = get_narrower (op0, &unsigned_arg); 8276 8277 final_type = result_type; 8278 8279 if (arg0 == op0 && final_type == TREE_TYPE (op0)) 8280 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0)); 8281 8282 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type) 8283 /* We can shorten only if the shift count is less than the 8284 number of bits in the smaller type size. */ 8285 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0 8286 /* We cannot drop an unsigned shift after sign-extension. */ 8287 && (!TYPE_UNSIGNED (final_type) || unsigned_arg)) 8288 { 8289 /* Do an unsigned shift if the operand was zero-extended. */ 8290 result_type 8291 = c_common_signed_or_unsigned_type (unsigned_arg, 8292 TREE_TYPE (arg0)); 8293 /* Convert value-to-be-shifted to that type. */ 8294 if (TREE_TYPE (op0) != result_type) 8295 op0 = convert (result_type, op0); 8296 converted = 1; 8297 } 8298 } 8299 8300 /* Comparison operations are shortened too but differently. 8301 They identify themselves by setting short_compare = 1. */ 8302 8303 if (short_compare) 8304 { 8305 /* Don't write &op0, etc., because that would prevent op0 8306 from being kept in a register. 8307 Instead, make copies of the our local variables and 8308 pass the copies by reference, then copy them back afterward. */ 8309 tree xop0 = op0, xop1 = op1, xresult_type = result_type; 8310 enum tree_code xresultcode = resultcode; 8311 tree val 8312 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode); 8313 8314 if (val != 0) 8315 return val; 8316 8317 op0 = xop0, op1 = xop1; 8318 converted = 1; 8319 resultcode = xresultcode; 8320 8321 if (warn_sign_compare && skip_evaluation == 0) 8322 { 8323 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0)); 8324 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1)); 8325 int unsignedp0, unsignedp1; 8326 tree primop0 = get_narrower (op0, &unsignedp0); 8327 tree primop1 = get_narrower (op1, &unsignedp1); 8328 8329 xop0 = orig_op0; 8330 xop1 = orig_op1; 8331 STRIP_TYPE_NOPS (xop0); 8332 STRIP_TYPE_NOPS (xop1); 8333 8334 /* Give warnings for comparisons between signed and unsigned 8335 quantities that may fail. 8336 8337 Do the checking based on the original operand trees, so that 8338 casts will be considered, but default promotions won't be. 8339 8340 Do not warn if the comparison is being done in a signed type, 8341 since the signed type will only be chosen if it can represent 8342 all the values of the unsigned type. */ 8343 if (!TYPE_UNSIGNED (result_type)) 8344 /* OK */; 8345 /* Do not warn if both operands are the same signedness. */ 8346 else if (op0_signed == op1_signed) 8347 /* OK */; 8348 else 8349 { 8350 tree sop, uop; 8351 bool ovf; 8352 8353 if (op0_signed) 8354 sop = xop0, uop = xop1; 8355 else 8356 sop = xop1, uop = xop0; 8357 8358 /* Do not warn if the signed quantity is an 8359 unsuffixed integer literal (or some static 8360 constant expression involving such literals or a 8361 conditional expression involving such literals) 8362 and it is non-negative. */ 8363 if (tree_expr_nonnegative_warnv_p (sop, &ovf)) 8364 /* OK */; 8365 /* Do not warn if the comparison is an equality operation, 8366 the unsigned quantity is an integral constant, and it 8367 would fit in the result if the result were signed. */ 8368 else if (TREE_CODE (uop) == INTEGER_CST 8369 && (resultcode == EQ_EXPR || resultcode == NE_EXPR) 8370 && int_fits_type_p 8371 (uop, c_common_signed_type (result_type))) 8372 /* OK */; 8373 /* Do not warn if the unsigned quantity is an enumeration 8374 constant and its maximum value would fit in the result 8375 if the result were signed. */ 8376 else if (TREE_CODE (uop) == INTEGER_CST 8377 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE 8378 && int_fits_type_p 8379 (TYPE_MAX_VALUE (TREE_TYPE (uop)), 8380 c_common_signed_type (result_type))) 8381 /* OK */; 8382 else 8383 warning (0, "comparison between signed and unsigned"); 8384 } 8385 8386 /* Warn if two unsigned values are being compared in a size 8387 larger than their original size, and one (and only one) is the 8388 result of a `~' operator. This comparison will always fail. 8389 8390 Also warn if one operand is a constant, and the constant 8391 does not have all bits set that are set in the ~ operand 8392 when it is extended. */ 8393 8394 if ((TREE_CODE (primop0) == BIT_NOT_EXPR) 8395 != (TREE_CODE (primop1) == BIT_NOT_EXPR)) 8396 { 8397 if (TREE_CODE (primop0) == BIT_NOT_EXPR) 8398 primop0 = get_narrower (TREE_OPERAND (primop0, 0), 8399 &unsignedp0); 8400 else 8401 primop1 = get_narrower (TREE_OPERAND (primop1, 0), 8402 &unsignedp1); 8403 8404 if (host_integerp (primop0, 0) || host_integerp (primop1, 0)) 8405 { 8406 tree primop; 8407 HOST_WIDE_INT constant, mask; 8408 int unsignedp, bits; 8409 8410 if (host_integerp (primop0, 0)) 8411 { 8412 primop = primop1; 8413 unsignedp = unsignedp1; 8414 constant = tree_low_cst (primop0, 0); 8415 } 8416 else 8417 { 8418 primop = primop0; 8419 unsignedp = unsignedp0; 8420 constant = tree_low_cst (primop1, 0); 8421 } 8422 8423 bits = TYPE_PRECISION (TREE_TYPE (primop)); 8424 if (bits < TYPE_PRECISION (result_type) 8425 && bits < HOST_BITS_PER_WIDE_INT && unsignedp) 8426 { 8427 mask = (~(HOST_WIDE_INT) 0) << bits; 8428 if ((mask & constant) != mask) 8429 warning (0, "comparison of promoted ~unsigned with constant"); 8430 } 8431 } 8432 else if (unsignedp0 && unsignedp1 8433 && (TYPE_PRECISION (TREE_TYPE (primop0)) 8434 < TYPE_PRECISION (result_type)) 8435 && (TYPE_PRECISION (TREE_TYPE (primop1)) 8436 < TYPE_PRECISION (result_type))) 8437 warning (0, "comparison of promoted ~unsigned with unsigned"); 8438 } 8439 } 8440 } 8441 } 8442 8443 /* At this point, RESULT_TYPE must be nonzero to avoid an error message. 8444 If CONVERTED is zero, both args will be converted to type RESULT_TYPE. 8445 Then the expression will be built. 8446 It will be given type FINAL_TYPE if that is nonzero; 8447 otherwise, it will be given type RESULT_TYPE. */ 8448 8449 if (!result_type) 8450 { 8451 binary_op_error (code, TREE_TYPE (op0), TREE_TYPE (op1)); 8452 return error_mark_node; 8453 } 8454 8455 if (!converted) 8456 { 8457 if (TREE_TYPE (op0) != result_type) 8458 op0 = convert_and_check (result_type, op0); 8459 if (TREE_TYPE (op1) != result_type) 8460 op1 = convert_and_check (result_type, op1); 8461 8462 /* This can happen if one operand has a vector type, and the other 8463 has a different type. */ 8464 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK) 8465 return error_mark_node; 8466 } 8467 8468 if (build_type == NULL_TREE) 8469 build_type = result_type; 8470 8471 { 8472 /* Treat expressions in initializers specially as they can't trap. */ 8473 tree result = require_constant_value ? fold_build2_initializer (resultcode, 8474 build_type, 8475 op0, op1) 8476 : fold_build2 (resultcode, build_type, 8477 op0, op1); 8478 8479 if (final_type != 0) 8480 result = convert (final_type, result); 8481 return result; 8482 } 8483} 8484 8485 8486/* Convert EXPR to be a truth-value, validating its type for this 8487 purpose. */ 8488 8489tree 8490c_objc_common_truthvalue_conversion (tree expr) 8491{ 8492 switch (TREE_CODE (TREE_TYPE (expr))) 8493 { 8494 case ARRAY_TYPE: 8495 error ("used array that cannot be converted to pointer where scalar is required"); 8496 return error_mark_node; 8497 8498 case RECORD_TYPE: 8499 error ("used struct type value where scalar is required"); 8500 return error_mark_node; 8501 8502 case UNION_TYPE: 8503 error ("used union type value where scalar is required"); 8504 return error_mark_node; 8505 8506 case FUNCTION_TYPE: 8507 gcc_unreachable (); 8508 8509 default: 8510 break; 8511 } 8512 8513 /* ??? Should we also give an error for void and vectors rather than 8514 leaving those to give errors later? */ 8515 return c_common_truthvalue_conversion (expr); 8516} 8517 8518 8519/* Convert EXPR to a contained DECL, updating *TC, *TI and *SE as 8520 required. */ 8521 8522tree 8523c_expr_to_decl (tree expr, bool *tc ATTRIBUTE_UNUSED, 8524 bool *ti ATTRIBUTE_UNUSED, bool *se) 8525{ 8526 if (TREE_CODE (expr) == COMPOUND_LITERAL_EXPR) 8527 { 8528 tree decl = COMPOUND_LITERAL_EXPR_DECL (expr); 8529 /* Executing a compound literal inside a function reinitializes 8530 it. */ 8531 if (!TREE_STATIC (decl)) 8532 *se = true; 8533 return decl; 8534 } 8535 else 8536 return expr; 8537} 8538 8539/* Like c_begin_compound_stmt, except force the retention of the BLOCK. */ 8540 8541tree 8542c_begin_omp_parallel (void) 8543{ 8544 tree block; 8545 8546 keep_next_level (); 8547 block = c_begin_compound_stmt (true); 8548 8549 return block; 8550} 8551 8552tree 8553c_finish_omp_parallel (tree clauses, tree block) 8554{ 8555 tree stmt; 8556 8557 block = c_end_compound_stmt (block, true); 8558 8559 stmt = make_node (OMP_PARALLEL); 8560 TREE_TYPE (stmt) = void_type_node; 8561 OMP_PARALLEL_CLAUSES (stmt) = clauses; 8562 OMP_PARALLEL_BODY (stmt) = block; 8563 8564 return add_stmt (stmt); 8565} 8566 8567/* For all elements of CLAUSES, validate them vs OpenMP constraints. 8568 Remove any elements from the list that are invalid. */ 8569 8570tree 8571c_finish_omp_clauses (tree clauses) 8572{ 8573 bitmap_head generic_head, firstprivate_head, lastprivate_head; 8574 tree c, t, *pc = &clauses; 8575 const char *name; 8576 8577 bitmap_obstack_initialize (NULL); 8578 bitmap_initialize (&generic_head, &bitmap_default_obstack); 8579 bitmap_initialize (&firstprivate_head, &bitmap_default_obstack); 8580 bitmap_initialize (&lastprivate_head, &bitmap_default_obstack); 8581 8582 for (pc = &clauses, c = clauses; c ; c = *pc) 8583 { 8584 bool remove = false; 8585 bool need_complete = false; 8586 bool need_implicitly_determined = false; 8587 8588 switch (OMP_CLAUSE_CODE (c)) 8589 { 8590 case OMP_CLAUSE_SHARED: 8591 name = "shared"; 8592 need_implicitly_determined = true; 8593 goto check_dup_generic; 8594 8595 case OMP_CLAUSE_PRIVATE: 8596 name = "private"; 8597 need_complete = true; 8598 need_implicitly_determined = true; 8599 goto check_dup_generic; 8600 8601 case OMP_CLAUSE_REDUCTION: 8602 name = "reduction"; 8603 need_implicitly_determined = true; 8604 t = OMP_CLAUSE_DECL (c); 8605 if (AGGREGATE_TYPE_P (TREE_TYPE (t)) 8606 || POINTER_TYPE_P (TREE_TYPE (t))) 8607 { 8608 error ("%qE has invalid type for %<reduction%>", t); 8609 remove = true; 8610 } 8611 else if (FLOAT_TYPE_P (TREE_TYPE (t))) 8612 { 8613 enum tree_code r_code = OMP_CLAUSE_REDUCTION_CODE (c); 8614 const char *r_name = NULL; 8615 8616 switch (r_code) 8617 { 8618 case PLUS_EXPR: 8619 case MULT_EXPR: 8620 case MINUS_EXPR: 8621 break; 8622 case BIT_AND_EXPR: 8623 r_name = "&"; 8624 break; 8625 case BIT_XOR_EXPR: 8626 r_name = "^"; 8627 break; 8628 case BIT_IOR_EXPR: 8629 r_name = "|"; 8630 break; 8631 case TRUTH_ANDIF_EXPR: 8632 r_name = "&&"; 8633 break; 8634 case TRUTH_ORIF_EXPR: 8635 r_name = "||"; 8636 break; 8637 default: 8638 gcc_unreachable (); 8639 } 8640 if (r_name) 8641 { 8642 error ("%qE has invalid type for %<reduction(%s)%>", 8643 t, r_name); 8644 remove = true; 8645 } 8646 } 8647 goto check_dup_generic; 8648 8649 case OMP_CLAUSE_COPYPRIVATE: 8650 name = "copyprivate"; 8651 goto check_dup_generic; 8652 8653 case OMP_CLAUSE_COPYIN: 8654 name = "copyin"; 8655 t = OMP_CLAUSE_DECL (c); 8656 if (TREE_CODE (t) != VAR_DECL || !DECL_THREAD_LOCAL_P (t)) 8657 { 8658 error ("%qE must be %<threadprivate%> for %<copyin%>", t); 8659 remove = true; 8660 } 8661 goto check_dup_generic; 8662 8663 check_dup_generic: 8664 t = OMP_CLAUSE_DECL (c); 8665 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL) 8666 { 8667 error ("%qE is not a variable in clause %qs", t, name); 8668 remove = true; 8669 } 8670 else if (bitmap_bit_p (&generic_head, DECL_UID (t)) 8671 || bitmap_bit_p (&firstprivate_head, DECL_UID (t)) 8672 || bitmap_bit_p (&lastprivate_head, DECL_UID (t))) 8673 { 8674 error ("%qE appears more than once in data clauses", t); 8675 remove = true; 8676 } 8677 else 8678 bitmap_set_bit (&generic_head, DECL_UID (t)); 8679 break; 8680 8681 case OMP_CLAUSE_FIRSTPRIVATE: 8682 name = "firstprivate"; 8683 t = OMP_CLAUSE_DECL (c); 8684 need_complete = true; 8685 need_implicitly_determined = true; 8686 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL) 8687 { 8688 error ("%qE is not a variable in clause %<firstprivate%>", t); 8689 remove = true; 8690 } 8691 else if (bitmap_bit_p (&generic_head, DECL_UID (t)) 8692 || bitmap_bit_p (&firstprivate_head, DECL_UID (t))) 8693 { 8694 error ("%qE appears more than once in data clauses", t); 8695 remove = true; 8696 } 8697 else 8698 bitmap_set_bit (&firstprivate_head, DECL_UID (t)); 8699 break; 8700 8701 case OMP_CLAUSE_LASTPRIVATE: 8702 name = "lastprivate"; 8703 t = OMP_CLAUSE_DECL (c); 8704 need_complete = true; 8705 need_implicitly_determined = true; 8706 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL) 8707 { 8708 error ("%qE is not a variable in clause %<lastprivate%>", t); 8709 remove = true; 8710 } 8711 else if (bitmap_bit_p (&generic_head, DECL_UID (t)) 8712 || bitmap_bit_p (&lastprivate_head, DECL_UID (t))) 8713 { 8714 error ("%qE appears more than once in data clauses", t); 8715 remove = true; 8716 } 8717 else 8718 bitmap_set_bit (&lastprivate_head, DECL_UID (t)); 8719 break; 8720 8721 case OMP_CLAUSE_IF: 8722 case OMP_CLAUSE_NUM_THREADS: 8723 case OMP_CLAUSE_SCHEDULE: 8724 case OMP_CLAUSE_NOWAIT: 8725 case OMP_CLAUSE_ORDERED: 8726 case OMP_CLAUSE_DEFAULT: 8727 pc = &OMP_CLAUSE_CHAIN (c); 8728 continue; 8729 8730 default: 8731 gcc_unreachable (); 8732 } 8733 8734 if (!remove) 8735 { 8736 t = OMP_CLAUSE_DECL (c); 8737 8738 if (need_complete) 8739 { 8740 t = require_complete_type (t); 8741 if (t == error_mark_node) 8742 remove = true; 8743 } 8744 8745 if (need_implicitly_determined) 8746 { 8747 const char *share_name = NULL; 8748 8749 if (TREE_CODE (t) == VAR_DECL && DECL_THREAD_LOCAL_P (t)) 8750 share_name = "threadprivate"; 8751 else switch (c_omp_predetermined_sharing (t)) 8752 { 8753 case OMP_CLAUSE_DEFAULT_UNSPECIFIED: 8754 break; 8755 case OMP_CLAUSE_DEFAULT_SHARED: 8756 share_name = "shared"; 8757 break; 8758 case OMP_CLAUSE_DEFAULT_PRIVATE: 8759 share_name = "private"; 8760 break; 8761 default: 8762 gcc_unreachable (); 8763 } 8764 if (share_name) 8765 { 8766 error ("%qE is predetermined %qs for %qs", 8767 t, share_name, name); 8768 remove = true; 8769 } 8770 } 8771 } 8772 8773 if (remove) 8774 *pc = OMP_CLAUSE_CHAIN (c); 8775 else 8776 pc = &OMP_CLAUSE_CHAIN (c); 8777 } 8778 8779 bitmap_obstack_release (NULL); 8780 return clauses; 8781} 8782