c-common.c revision 259268
1/* Subroutines shared by all languages that are variants of C. 2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 3 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc. 4 5This file is part of GCC. 6 7GCC is free software; you can redistribute it and/or modify it under 8the terms of the GNU General Public License as published by the Free 9Software Foundation; either version 2, or (at your option) any later 10version. 11 12GCC is distributed in the hope that it will be useful, but WITHOUT ANY 13WARRANTY; without even the implied warranty of MERCHANTABILITY or 14FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 15for more details. 16 17You should have received a copy of the GNU General Public License 18along with GCC; see the file COPYING. If not, write to the Free 19Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 2002110-1301, USA. */ 21 22#include "config.h" 23#include "system.h" 24#include "coretypes.h" 25#include "tm.h" 26#include "intl.h" 27#include "tree.h" 28#include "flags.h" 29#include "output.h" 30#include "c-pragma.h" 31#include "rtl.h" 32#include "ggc.h" 33#include "varray.h" 34#include "expr.h" 35#include "c-common.h" 36#include "diagnostic.h" 37#include "tm_p.h" 38#include "obstack.h" 39#include "cpplib.h" 40#include "target.h" 41#include "langhooks.h" 42#include "tree-inline.h" 43#include "c-tree.h" 44#include "toplev.h" 45#include "tree-iterator.h" 46#include "hashtab.h" 47#include "tree-mudflap.h" 48#include "opts.h" 49#include "real.h" 50#include "cgraph.h" 51 52cpp_reader *parse_in; /* Declared in c-pragma.h. */ 53 54/* We let tm.h override the types used here, to handle trivial differences 55 such as the choice of unsigned int or long unsigned int for size_t. 56 When machines start needing nontrivial differences in the size type, 57 it would be best to do something here to figure out automatically 58 from other information what type to use. */ 59 60#ifndef SIZE_TYPE 61#define SIZE_TYPE "long unsigned int" 62#endif 63 64#ifndef PID_TYPE 65#define PID_TYPE "int" 66#endif 67 68#ifndef WCHAR_TYPE 69#define WCHAR_TYPE "int" 70#endif 71 72/* WCHAR_TYPE gets overridden by -fshort-wchar. */ 73#define MODIFIED_WCHAR_TYPE \ 74 (flag_short_wchar ? "short unsigned int" : WCHAR_TYPE) 75 76#ifndef PTRDIFF_TYPE 77#define PTRDIFF_TYPE "long int" 78#endif 79 80#ifndef WINT_TYPE 81#define WINT_TYPE "unsigned int" 82#endif 83 84#ifndef INTMAX_TYPE 85#define INTMAX_TYPE ((INT_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \ 86 ? "int" \ 87 : ((LONG_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \ 88 ? "long int" \ 89 : "long long int")) 90#endif 91 92#ifndef UINTMAX_TYPE 93#define UINTMAX_TYPE ((INT_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \ 94 ? "unsigned int" \ 95 : ((LONG_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \ 96 ? "long unsigned int" \ 97 : "long long unsigned int")) 98#endif 99 100/* The following symbols are subsumed in the c_global_trees array, and 101 listed here individually for documentation purposes. 102 103 INTEGER_TYPE and REAL_TYPE nodes for the standard data types. 104 105 tree short_integer_type_node; 106 tree long_integer_type_node; 107 tree long_long_integer_type_node; 108 109 tree short_unsigned_type_node; 110 tree long_unsigned_type_node; 111 tree long_long_unsigned_type_node; 112 113 tree truthvalue_type_node; 114 tree truthvalue_false_node; 115 tree truthvalue_true_node; 116 117 tree ptrdiff_type_node; 118 119 tree unsigned_char_type_node; 120 tree signed_char_type_node; 121 tree wchar_type_node; 122 tree signed_wchar_type_node; 123 tree unsigned_wchar_type_node; 124 125 tree float_type_node; 126 tree double_type_node; 127 tree long_double_type_node; 128 129 tree complex_integer_type_node; 130 tree complex_float_type_node; 131 tree complex_double_type_node; 132 tree complex_long_double_type_node; 133 134 tree dfloat32_type_node; 135 tree dfloat64_type_node; 136 tree_dfloat128_type_node; 137 138 tree intQI_type_node; 139 tree intHI_type_node; 140 tree intSI_type_node; 141 tree intDI_type_node; 142 tree intTI_type_node; 143 144 tree unsigned_intQI_type_node; 145 tree unsigned_intHI_type_node; 146 tree unsigned_intSI_type_node; 147 tree unsigned_intDI_type_node; 148 tree unsigned_intTI_type_node; 149 150 tree widest_integer_literal_type_node; 151 tree widest_unsigned_literal_type_node; 152 153 Nodes for types `void *' and `const void *'. 154 155 tree ptr_type_node, const_ptr_type_node; 156 157 Nodes for types `char *' and `const char *'. 158 159 tree string_type_node, const_string_type_node; 160 161 Type `char[SOMENUMBER]'. 162 Used when an array of char is needed and the size is irrelevant. 163 164 tree char_array_type_node; 165 166 Type `int[SOMENUMBER]' or something like it. 167 Used when an array of int needed and the size is irrelevant. 168 169 tree int_array_type_node; 170 171 Type `wchar_t[SOMENUMBER]' or something like it. 172 Used when a wide string literal is created. 173 174 tree wchar_array_type_node; 175 176 Type `int ()' -- used for implicit declaration of functions. 177 178 tree default_function_type; 179 180 A VOID_TYPE node, packaged in a TREE_LIST. 181 182 tree void_list_node; 183 184 The lazily created VAR_DECLs for __FUNCTION__, __PRETTY_FUNCTION__, 185 and __func__. (C doesn't generate __FUNCTION__ and__PRETTY_FUNCTION__ 186 VAR_DECLS, but C++ does.) 187 188 tree function_name_decl_node; 189 tree pretty_function_name_decl_node; 190 tree c99_function_name_decl_node; 191 192 Stack of nested function name VAR_DECLs. 193 194 tree saved_function_name_decls; 195 196*/ 197 198tree c_global_trees[CTI_MAX]; 199 200/* Switches common to the C front ends. */ 201 202/* Nonzero if prepreprocessing only. */ 203 204int flag_preprocess_only; 205 206/* Nonzero means don't output line number information. */ 207 208char flag_no_line_commands; 209 210/* Nonzero causes -E output not to be done, but directives such as 211 #define that have side effects are still obeyed. */ 212 213char flag_no_output; 214 215/* Nonzero means dump macros in some fashion. */ 216 217char flag_dump_macros; 218 219/* Nonzero means pass #include lines through to the output. */ 220 221char flag_dump_includes; 222 223/* Nonzero means process PCH files while preprocessing. */ 224 225bool flag_pch_preprocess; 226 227/* The file name to which we should write a precompiled header, or 228 NULL if no header will be written in this compile. */ 229 230const char *pch_file; 231 232/* Nonzero if an ISO standard was selected. It rejects macros in the 233 user's namespace. */ 234int flag_iso; 235 236/* Nonzero if -undef was given. It suppresses target built-in macros 237 and assertions. */ 238int flag_undef; 239 240/* Nonzero means don't recognize the non-ANSI builtin functions. */ 241 242int flag_no_builtin; 243 244/* Nonzero means don't recognize the non-ANSI builtin functions. 245 -ansi sets this. */ 246 247int flag_no_nonansi_builtin; 248 249/* Nonzero means give `double' the same size as `float'. */ 250 251int flag_short_double; 252 253/* Nonzero means give `wchar_t' the same size as `short'. */ 254 255int flag_short_wchar; 256 257/* Nonzero means allow Microsoft extensions without warnings or errors. */ 258int flag_ms_extensions; 259 260/* Nonzero means don't recognize the keyword `asm'. */ 261 262int flag_no_asm; 263 264/* Nonzero means to treat bitfields as signed unless they say `unsigned'. */ 265 266int flag_signed_bitfields = 1; 267 268/* Warn about #pragma directives that are not recognized. */ 269 270int warn_unknown_pragmas; /* Tri state variable. */ 271 272/* Warn about format/argument anomalies in calls to formatted I/O functions 273 (*printf, *scanf, strftime, strfmon, etc.). */ 274 275int warn_format; 276 277/* Warn about using __null (as NULL in C++) as sentinel. For code compiled 278 with GCC this doesn't matter as __null is guaranteed to have the right 279 size. */ 280 281int warn_strict_null_sentinel; 282 283/* Zero means that faster, ...NonNil variants of objc_msgSend... 284 calls will be used in ObjC; passing nil receivers to such calls 285 will most likely result in crashes. */ 286int flag_nil_receivers = 1; 287 288/* Nonzero means that code generation will be altered to support 289 "zero-link" execution. This currently affects ObjC only, but may 290 affect other languages in the future. */ 291int flag_zero_link = 0; 292 293/* Nonzero means emit an '__OBJC, __image_info' for the current translation 294 unit. It will inform the ObjC runtime that class definition(s) herein 295 contained are to replace one(s) previously loaded. */ 296int flag_replace_objc_classes = 0; 297 298/* C/ObjC language option variables. */ 299 300 301/* Nonzero means allow type mismatches in conditional expressions; 302 just make their values `void'. */ 303 304int flag_cond_mismatch; 305 306/* Nonzero means enable C89 Amendment 1 features. */ 307 308int flag_isoc94; 309 310/* Nonzero means use the ISO C99 dialect of C. */ 311 312int flag_isoc99; 313 314/* Nonzero means that we have builtin functions, and main is an int. */ 315 316int flag_hosted = 1; 317 318/* Warn if main is suspicious. */ 319 320int warn_main; 321 322 323/* ObjC language option variables. */ 324 325 326/* Open and close the file for outputting class declarations, if 327 requested (ObjC). */ 328 329int flag_gen_declaration; 330 331/* Tells the compiler that this is a special run. Do not perform any 332 compiling, instead we are to test some platform dependent features 333 and output a C header file with appropriate definitions. */ 334 335int print_struct_values; 336 337/* Tells the compiler what is the constant string class for Objc. */ 338 339const char *constant_string_class_name; 340 341 342/* C++ language option variables. */ 343 344 345/* Nonzero means don't recognize any extension keywords. */ 346 347int flag_no_gnu_keywords; 348 349/* Nonzero means do emit exported implementations of functions even if 350 they can be inlined. */ 351 352int flag_implement_inlines = 1; 353 354/* Nonzero means that implicit instantiations will be emitted if needed. */ 355 356int flag_implicit_templates = 1; 357 358/* Nonzero means that implicit instantiations of inline templates will be 359 emitted if needed, even if instantiations of non-inline templates 360 aren't. */ 361 362int flag_implicit_inline_templates = 1; 363 364/* Nonzero means generate separate instantiation control files and 365 juggle them at link time. */ 366 367int flag_use_repository; 368 369/* Nonzero if we want to issue diagnostics that the standard says are not 370 required. */ 371 372int flag_optional_diags = 1; 373 374/* Nonzero means we should attempt to elide constructors when possible. */ 375 376int flag_elide_constructors = 1; 377 378/* Nonzero means that member functions defined in class scope are 379 inline by default. */ 380 381int flag_default_inline = 1; 382 383/* Controls whether compiler generates 'type descriptor' that give 384 run-time type information. */ 385 386int flag_rtti = 1; 387 388/* Nonzero if we want to conserve space in the .o files. We do this 389 by putting uninitialized data and runtime initialized data into 390 .common instead of .data at the expense of not flagging multiple 391 definitions. */ 392 393int flag_conserve_space; 394 395/* Nonzero if we want to obey access control semantics. */ 396 397int flag_access_control = 1; 398 399/* Nonzero if we want to check the return value of new and avoid calling 400 constructors if it is a null pointer. */ 401 402int flag_check_new; 403 404/* Nonzero if we want the new ISO rules for pushing a new scope for `for' 405 initialization variables. 406 0: Old rules, set by -fno-for-scope. 407 2: New ISO rules, set by -ffor-scope. 408 1: Try to implement new ISO rules, but with backup compatibility 409 (and warnings). This is the default, for now. */ 410 411int flag_new_for_scope = 1; 412 413/* Nonzero if we want to emit defined symbols with common-like linkage as 414 weak symbols where possible, in order to conform to C++ semantics. 415 Otherwise, emit them as local symbols. */ 416 417int flag_weak = 1; 418 419/* 0 means we want the preprocessor to not emit line directives for 420 the current working directory. 1 means we want it to do it. -1 421 means we should decide depending on whether debugging information 422 is being emitted or not. */ 423 424int flag_working_directory = -1; 425 426/* Nonzero to use __cxa_atexit, rather than atexit, to register 427 destructors for local statics and global objects. '2' means it has been 428 set nonzero as a default, not by a command-line flag. */ 429 430int flag_use_cxa_atexit = DEFAULT_USE_CXA_ATEXIT; 431 432/* Nonzero to use __cxa_get_exception_ptr in C++ exception-handling 433 code. '2' means it has not been set explicitly on the command line. */ 434 435int flag_use_cxa_get_exception_ptr = 2; 436 437/* Nonzero means make the default pedwarns warnings instead of errors. 438 The value of this flag is ignored if -pedantic is specified. */ 439 440int flag_permissive; 441 442/* Nonzero means to implement standard semantics for exception 443 specifications, calling unexpected if an exception is thrown that 444 doesn't match the specification. Zero means to treat them as 445 assertions and optimize accordingly, but not check them. */ 446 447int flag_enforce_eh_specs = 1; 448 449/* Nonzero means to generate thread-safe code for initializing local 450 statics. */ 451 452int flag_threadsafe_statics = 1; 453 454/* Nonzero means warn about implicit declarations. */ 455 456int warn_implicit = 1; 457 458/* Maximum template instantiation depth. This limit is rather 459 arbitrary, but it exists to limit the time it takes to notice 460 infinite template instantiations. */ 461 462int max_tinst_depth = 500; 463 464 465 466/* The elements of `ridpointers' are identifier nodes for the reserved 467 type names and storage classes. It is indexed by a RID_... value. */ 468tree *ridpointers; 469 470tree (*make_fname_decl) (tree, int); 471 472/* Nonzero means the expression being parsed will never be evaluated. 473 This is a count, since unevaluated expressions can nest. */ 474int skip_evaluation; 475 476/* Information about how a function name is generated. */ 477struct fname_var_t 478{ 479 tree *const decl; /* pointer to the VAR_DECL. */ 480 const unsigned rid; /* RID number for the identifier. */ 481 const int pretty; /* How pretty is it? */ 482}; 483 484/* The three ways of getting then name of the current function. */ 485 486const struct fname_var_t fname_vars[] = 487{ 488 /* C99 compliant __func__, must be first. */ 489 {&c99_function_name_decl_node, RID_C99_FUNCTION_NAME, 0}, 490 /* GCC __FUNCTION__ compliant. */ 491 {&function_name_decl_node, RID_FUNCTION_NAME, 0}, 492 /* GCC __PRETTY_FUNCTION__ compliant. */ 493 {&pretty_function_name_decl_node, RID_PRETTY_FUNCTION_NAME, 1}, 494 {NULL, 0, 0}, 495}; 496 497static int constant_fits_type_p (tree, tree); 498static tree check_case_value (tree); 499static bool check_case_bounds (tree, tree, tree *, tree *); 500 501static tree handle_packed_attribute (tree *, tree, tree, int, bool *); 502static tree handle_nocommon_attribute (tree *, tree, tree, int, bool *); 503static tree handle_common_attribute (tree *, tree, tree, int, bool *); 504static tree handle_noreturn_attribute (tree *, tree, tree, int, bool *); 505static tree handle_noinline_attribute (tree *, tree, tree, int, bool *); 506static tree handle_always_inline_attribute (tree *, tree, tree, int, 507 bool *); 508static tree handle_gnu_inline_attribute (tree *, tree, tree, int, 509 bool *); 510static tree handle_flatten_attribute (tree *, tree, tree, int, bool *); 511static tree handle_used_attribute (tree *, tree, tree, int, bool *); 512static tree handle_unused_attribute (tree *, tree, tree, int, bool *); 513static tree handle_externally_visible_attribute (tree *, tree, tree, int, 514 bool *); 515static tree handle_const_attribute (tree *, tree, tree, int, bool *); 516static tree handle_transparent_union_attribute (tree *, tree, tree, 517 int, bool *); 518static tree handle_constructor_attribute (tree *, tree, tree, int, bool *); 519static tree handle_destructor_attribute (tree *, tree, tree, int, bool *); 520static tree handle_mode_attribute (tree *, tree, tree, int, bool *); 521static tree handle_section_attribute (tree *, tree, tree, int, bool *); 522static tree handle_aligned_attribute (tree *, tree, tree, int, bool *); 523static tree handle_weak_attribute (tree *, tree, tree, int, bool *) ; 524static tree handle_alias_attribute (tree *, tree, tree, int, bool *); 525static tree handle_weakref_attribute (tree *, tree, tree, int, bool *) ; 526static tree handle_visibility_attribute (tree *, tree, tree, int, 527 bool *); 528static tree handle_tls_model_attribute (tree *, tree, tree, int, 529 bool *); 530static tree handle_no_instrument_function_attribute (tree *, tree, 531 tree, int, bool *); 532static tree handle_malloc_attribute (tree *, tree, tree, int, bool *); 533static tree handle_returns_twice_attribute (tree *, tree, tree, int, bool *); 534static tree handle_no_limit_stack_attribute (tree *, tree, tree, int, 535 bool *); 536static tree handle_pure_attribute (tree *, tree, tree, int, bool *); 537static tree handle_novops_attribute (tree *, tree, tree, int, bool *); 538static tree handle_deprecated_attribute (tree *, tree, tree, int, 539 bool *); 540static tree handle_vector_size_attribute (tree *, tree, tree, int, 541 bool *); 542static tree handle_nonnull_attribute (tree *, tree, tree, int, bool *); 543static tree handle_nothrow_attribute (tree *, tree, tree, int, bool *); 544static tree handle_cleanup_attribute (tree *, tree, tree, int, bool *); 545static tree handle_warn_unused_result_attribute (tree *, tree, tree, int, 546 bool *); 547static tree handle_sentinel_attribute (tree *, tree, tree, int, bool *); 548 549static void check_function_nonnull (tree, tree); 550static void check_nonnull_arg (void *, tree, unsigned HOST_WIDE_INT); 551static bool nonnull_check_p (tree, unsigned HOST_WIDE_INT); 552static bool get_nonnull_operand (tree, unsigned HOST_WIDE_INT *); 553static int resort_field_decl_cmp (const void *, const void *); 554 555/* Table of machine-independent attributes common to all C-like languages. */ 556const struct attribute_spec c_common_attribute_table[] = 557{ 558 /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */ 559 { "packed", 0, 0, false, false, false, 560 handle_packed_attribute }, 561 { "nocommon", 0, 0, true, false, false, 562 handle_nocommon_attribute }, 563 { "common", 0, 0, true, false, false, 564 handle_common_attribute }, 565 /* FIXME: logically, noreturn attributes should be listed as 566 "false, true, true" and apply to function types. But implementing this 567 would require all the places in the compiler that use TREE_THIS_VOLATILE 568 on a decl to identify non-returning functions to be located and fixed 569 to check the function type instead. */ 570 { "noreturn", 0, 0, true, false, false, 571 handle_noreturn_attribute }, 572 { "volatile", 0, 0, true, false, false, 573 handle_noreturn_attribute }, 574 { "noinline", 0, 0, true, false, false, 575 handle_noinline_attribute }, 576 { "always_inline", 0, 0, true, false, false, 577 handle_always_inline_attribute }, 578 { "gnu_inline", 0, 0, true, false, false, 579 handle_gnu_inline_attribute }, 580 { "flatten", 0, 0, true, false, false, 581 handle_flatten_attribute }, 582 { "used", 0, 0, true, false, false, 583 handle_used_attribute }, 584 { "unused", 0, 0, false, false, false, 585 handle_unused_attribute }, 586 { "externally_visible", 0, 0, true, false, false, 587 handle_externally_visible_attribute }, 588 /* The same comments as for noreturn attributes apply to const ones. */ 589 { "const", 0, 0, true, false, false, 590 handle_const_attribute }, 591 { "transparent_union", 0, 0, false, false, false, 592 handle_transparent_union_attribute }, 593 { "constructor", 0, 0, true, false, false, 594 handle_constructor_attribute }, 595 { "destructor", 0, 0, true, false, false, 596 handle_destructor_attribute }, 597 { "mode", 1, 1, false, true, false, 598 handle_mode_attribute }, 599 { "section", 1, 1, true, false, false, 600 handle_section_attribute }, 601 { "aligned", 0, 1, false, false, false, 602 handle_aligned_attribute }, 603 { "weak", 0, 0, true, false, false, 604 handle_weak_attribute }, 605 { "alias", 1, 1, true, false, false, 606 handle_alias_attribute }, 607 { "weakref", 0, 1, true, false, false, 608 handle_weakref_attribute }, 609 { "no_instrument_function", 0, 0, true, false, false, 610 handle_no_instrument_function_attribute }, 611 { "malloc", 0, 0, true, false, false, 612 handle_malloc_attribute }, 613 { "returns_twice", 0, 0, true, false, false, 614 handle_returns_twice_attribute }, 615 { "no_stack_limit", 0, 0, true, false, false, 616 handle_no_limit_stack_attribute }, 617 { "pure", 0, 0, true, false, false, 618 handle_pure_attribute }, 619 /* For internal use (marking of builtins) only. The name contains space 620 to prevent its usage in source code. */ 621 { "no vops", 0, 0, true, false, false, 622 handle_novops_attribute }, 623 { "deprecated", 0, 0, false, false, false, 624 handle_deprecated_attribute }, 625 { "vector_size", 1, 1, false, true, false, 626 handle_vector_size_attribute }, 627 { "visibility", 1, 1, false, false, false, 628 handle_visibility_attribute }, 629 { "tls_model", 1, 1, true, false, false, 630 handle_tls_model_attribute }, 631 { "nonnull", 0, -1, false, true, true, 632 handle_nonnull_attribute }, 633 { "nothrow", 0, 0, true, false, false, 634 handle_nothrow_attribute }, 635 { "may_alias", 0, 0, false, true, false, NULL }, 636 { "cleanup", 1, 1, true, false, false, 637 handle_cleanup_attribute }, 638 { "warn_unused_result", 0, 0, false, true, true, 639 handle_warn_unused_result_attribute }, 640 { "sentinel", 0, 1, false, true, true, 641 handle_sentinel_attribute }, 642 { NULL, 0, 0, false, false, false, NULL } 643}; 644 645/* Give the specifications for the format attributes, used by C and all 646 descendants. */ 647 648const struct attribute_spec c_common_format_attribute_table[] = 649{ 650 /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */ 651 { "format", 3, 3, false, true, true, 652 handle_format_attribute }, 653 { "format_arg", 1, 1, false, true, true, 654 handle_format_arg_attribute }, 655 { NULL, 0, 0, false, false, false, NULL } 656}; 657 658/* Push current bindings for the function name VAR_DECLS. */ 659 660void 661start_fname_decls (void) 662{ 663 unsigned ix; 664 tree saved = NULL_TREE; 665 666 for (ix = 0; fname_vars[ix].decl; ix++) 667 { 668 tree decl = *fname_vars[ix].decl; 669 670 if (decl) 671 { 672 saved = tree_cons (decl, build_int_cst (NULL_TREE, ix), saved); 673 *fname_vars[ix].decl = NULL_TREE; 674 } 675 } 676 if (saved || saved_function_name_decls) 677 /* Normally they'll have been NULL, so only push if we've got a 678 stack, or they are non-NULL. */ 679 saved_function_name_decls = tree_cons (saved, NULL_TREE, 680 saved_function_name_decls); 681} 682 683/* Finish up the current bindings, adding them into the current function's 684 statement tree. This must be done _before_ finish_stmt_tree is called. 685 If there is no current function, we must be at file scope and no statements 686 are involved. Pop the previous bindings. */ 687 688void 689finish_fname_decls (void) 690{ 691 unsigned ix; 692 tree stmts = NULL_TREE; 693 tree stack = saved_function_name_decls; 694 695 for (; stack && TREE_VALUE (stack); stack = TREE_CHAIN (stack)) 696 append_to_statement_list (TREE_VALUE (stack), &stmts); 697 698 if (stmts) 699 { 700 tree *bodyp = &DECL_SAVED_TREE (current_function_decl); 701 702 if (TREE_CODE (*bodyp) == BIND_EXPR) 703 bodyp = &BIND_EXPR_BODY (*bodyp); 704 705 append_to_statement_list_force (*bodyp, &stmts); 706 *bodyp = stmts; 707 } 708 709 for (ix = 0; fname_vars[ix].decl; ix++) 710 *fname_vars[ix].decl = NULL_TREE; 711 712 if (stack) 713 { 714 /* We had saved values, restore them. */ 715 tree saved; 716 717 for (saved = TREE_PURPOSE (stack); saved; saved = TREE_CHAIN (saved)) 718 { 719 tree decl = TREE_PURPOSE (saved); 720 unsigned ix = TREE_INT_CST_LOW (TREE_VALUE (saved)); 721 722 *fname_vars[ix].decl = decl; 723 } 724 stack = TREE_CHAIN (stack); 725 } 726 saved_function_name_decls = stack; 727} 728 729/* Return the text name of the current function, suitably prettified 730 by PRETTY_P. Return string must be freed by caller. */ 731 732const char * 733fname_as_string (int pretty_p) 734{ 735 const char *name = "top level"; 736 char *namep; 737 int vrb = 2; 738 739 if (!pretty_p) 740 { 741 name = ""; 742 vrb = 0; 743 } 744 745 if (current_function_decl) 746 name = lang_hooks.decl_printable_name (current_function_decl, vrb); 747 748 if (c_lex_string_translate) 749 { 750 int len = strlen (name) + 3; /* Two for '"'s. One for NULL. */ 751 cpp_string cstr = { 0, 0 }, strname; 752 753 namep = XNEWVEC (char, len); 754 snprintf (namep, len, "\"%s\"", name); 755 strname.text = (unsigned char *) namep; 756 strname.len = len - 1; 757 758 if (cpp_interpret_string (parse_in, &strname, 1, &cstr, false)) 759 { 760 XDELETEVEC (namep); 761 return (char *) cstr.text; 762 } 763 } 764 else 765 namep = xstrdup (name); 766 767 return namep; 768} 769 770/* Expand DECL if it declares an entity not handled by the 771 common code. */ 772 773int 774c_expand_decl (tree decl) 775{ 776 if (TREE_CODE (decl) == VAR_DECL && !TREE_STATIC (decl)) 777 { 778 /* Let the back-end know about this variable. */ 779 if (!anon_aggr_type_p (TREE_TYPE (decl))) 780 emit_local_var (decl); 781 else 782 expand_anon_union_decl (decl, NULL_TREE, 783 DECL_ANON_UNION_ELEMS (decl)); 784 } 785 else 786 return 0; 787 788 return 1; 789} 790 791 792/* Return the VAR_DECL for a const char array naming the current 793 function. If the VAR_DECL has not yet been created, create it 794 now. RID indicates how it should be formatted and IDENTIFIER_NODE 795 ID is its name (unfortunately C and C++ hold the RID values of 796 keywords in different places, so we can't derive RID from ID in 797 this language independent code. */ 798 799tree 800fname_decl (unsigned int rid, tree id) 801{ 802 unsigned ix; 803 tree decl = NULL_TREE; 804 805 for (ix = 0; fname_vars[ix].decl; ix++) 806 if (fname_vars[ix].rid == rid) 807 break; 808 809 decl = *fname_vars[ix].decl; 810 if (!decl) 811 { 812 /* If a tree is built here, it would normally have the lineno of 813 the current statement. Later this tree will be moved to the 814 beginning of the function and this line number will be wrong. 815 To avoid this problem set the lineno to 0 here; that prevents 816 it from appearing in the RTL. */ 817 tree stmts; 818 location_t saved_location = input_location; 819#ifdef USE_MAPPED_LOCATION 820 input_location = UNKNOWN_LOCATION; 821#else 822 input_line = 0; 823#endif 824 825 stmts = push_stmt_list (); 826 decl = (*make_fname_decl) (id, fname_vars[ix].pretty); 827 stmts = pop_stmt_list (stmts); 828 if (!IS_EMPTY_STMT (stmts)) 829 saved_function_name_decls 830 = tree_cons (decl, stmts, saved_function_name_decls); 831 *fname_vars[ix].decl = decl; 832 input_location = saved_location; 833 } 834 if (!ix && !current_function_decl) 835 pedwarn ("%qD is not defined outside of function scope", decl); 836 837 return decl; 838} 839 840/* Given a STRING_CST, give it a suitable array-of-chars data type. */ 841 842tree 843fix_string_type (tree value) 844{ 845 const int wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT; 846 const int wide_flag = TREE_TYPE (value) == wchar_array_type_node; 847 int length = TREE_STRING_LENGTH (value); 848 int nchars; 849 tree e_type, i_type, a_type; 850 851 /* Compute the number of elements, for the array type. */ 852 nchars = wide_flag ? length / wchar_bytes : length; 853 854 /* C89 2.2.4.1, C99 5.2.4.1 (Translation limits). The analogous 855 limit in C++98 Annex B is very large (65536) and is not normative, 856 so we do not diagnose it (warn_overlength_strings is forced off 857 in c_common_post_options). */ 858 if (warn_overlength_strings) 859 { 860 const int nchars_max = flag_isoc99 ? 4095 : 509; 861 const int relevant_std = flag_isoc99 ? 99 : 90; 862 if (nchars - 1 > nchars_max) 863 /* Translators: The %d after 'ISO C' will be 90 or 99. Do not 864 separate the %d from the 'C'. 'ISO' should not be 865 translated, but it may be moved after 'C%d' in languages 866 where modifiers follow nouns. */ 867 pedwarn ("string length %qd is greater than the length %qd " 868 "ISO C%d compilers are required to support", 869 nchars - 1, nchars_max, relevant_std); 870 } 871 872 /* Create the array type for the string constant. The ISO C++ 873 standard says that a string literal has type `const char[N]' or 874 `const wchar_t[N]'. We use the same logic when invoked as a C 875 front-end with -Wwrite-strings. 876 ??? We should change the type of an expression depending on the 877 state of a warning flag. We should just be warning -- see how 878 this is handled in the C++ front-end for the deprecated implicit 879 conversion from string literals to `char*' or `wchar_t*'. 880 881 The C++ front end relies on TYPE_MAIN_VARIANT of a cv-qualified 882 array type being the unqualified version of that type. 883 Therefore, if we are constructing an array of const char, we must 884 construct the matching unqualified array type first. The C front 885 end does not require this, but it does no harm, so we do it 886 unconditionally. */ 887 e_type = wide_flag ? wchar_type_node : char_type_node; 888 i_type = build_index_type (build_int_cst (NULL_TREE, nchars - 1)); 889 a_type = build_array_type (e_type, i_type); 890 if (c_dialect_cxx() || warn_write_strings) 891 a_type = c_build_qualified_type (a_type, TYPE_QUAL_CONST); 892 893 TREE_TYPE (value) = a_type; 894 TREE_CONSTANT (value) = 1; 895 TREE_INVARIANT (value) = 1; 896 TREE_READONLY (value) = 1; 897 TREE_STATIC (value) = 1; 898 return value; 899} 900 901/* Print a warning if a constant expression had overflow in folding. 902 Invoke this function on every expression that the language 903 requires to be a constant expression. 904 Note the ANSI C standard says it is erroneous for a 905 constant expression to overflow. */ 906 907void 908constant_expression_warning (tree value) 909{ 910 if ((TREE_CODE (value) == INTEGER_CST || TREE_CODE (value) == REAL_CST 911 || TREE_CODE (value) == VECTOR_CST 912 || TREE_CODE (value) == COMPLEX_CST) 913 && TREE_CONSTANT_OVERFLOW (value) 914 && warn_overflow 915 && pedantic) 916 pedwarn ("overflow in constant expression"); 917} 918 919/* Print a warning if an expression had overflow in folding. 920 Invoke this function on every expression that 921 (1) appears in the source code, and 922 (2) might be a constant expression that overflowed, and 923 (3) is not already checked by convert_and_check; 924 however, do not invoke this function on operands of explicit casts. */ 925 926void 927overflow_warning (tree value) 928{ 929 if ((TREE_CODE (value) == INTEGER_CST 930 || (TREE_CODE (value) == COMPLEX_CST 931 && TREE_CODE (TREE_REALPART (value)) == INTEGER_CST)) 932 && TREE_OVERFLOW (value)) 933 { 934 TREE_OVERFLOW (value) = 0; 935 if (skip_evaluation == 0) 936 warning (OPT_Woverflow, "integer overflow in expression"); 937 } 938 else if ((TREE_CODE (value) == REAL_CST 939 || (TREE_CODE (value) == COMPLEX_CST 940 && TREE_CODE (TREE_REALPART (value)) == REAL_CST)) 941 && TREE_OVERFLOW (value)) 942 { 943 TREE_OVERFLOW (value) = 0; 944 if (skip_evaluation == 0) 945 warning (OPT_Woverflow, "floating point overflow in expression"); 946 } 947 else if (TREE_CODE (value) == VECTOR_CST && TREE_OVERFLOW (value)) 948 { 949 TREE_OVERFLOW (value) = 0; 950 if (skip_evaluation == 0) 951 warning (OPT_Woverflow, "vector overflow in expression"); 952 } 953} 954 955/* Print a warning if a large constant is truncated to unsigned, 956 or if -Wconversion is used and a constant < 0 is converted to unsigned. 957 Invoke this function on every expression that might be implicitly 958 converted to an unsigned type. */ 959 960static void 961unsigned_conversion_warning (tree result, tree operand) 962{ 963 tree type = TREE_TYPE (result); 964 965 if (TREE_CODE (operand) == INTEGER_CST 966 && TREE_CODE (type) == INTEGER_TYPE 967 && TYPE_UNSIGNED (type) 968 && skip_evaluation == 0 969 && !int_fits_type_p (operand, type)) 970 { 971 if (!int_fits_type_p (operand, c_common_signed_type (type))) 972 /* This detects cases like converting -129 or 256 to unsigned char. */ 973 warning (OPT_Woverflow, 974 "large integer implicitly truncated to unsigned type"); 975 else 976 warning (OPT_Wconversion, 977 "negative integer implicitly converted to unsigned type"); 978 } 979} 980 981/* Print a warning about casts that might indicate violation 982 of strict aliasing rules if -Wstrict-aliasing is used and 983 strict aliasing mode is in effect. OTYPE is the original 984 TREE_TYPE of EXPR, and TYPE the type we're casting to. */ 985 986void 987strict_aliasing_warning (tree otype, tree type, tree expr) 988{ 989 if (flag_strict_aliasing && warn_strict_aliasing 990 && POINTER_TYPE_P (type) && POINTER_TYPE_P (otype) 991 && TREE_CODE (expr) == ADDR_EXPR 992 && (DECL_P (TREE_OPERAND (expr, 0)) 993 || handled_component_p (TREE_OPERAND (expr, 0))) 994 && !VOID_TYPE_P (TREE_TYPE (type))) 995 { 996 /* Casting the address of an object to non void pointer. Warn 997 if the cast breaks type based aliasing. */ 998 if (!COMPLETE_TYPE_P (TREE_TYPE (type))) 999 warning (OPT_Wstrict_aliasing, "type-punning to incomplete type " 1000 "might break strict-aliasing rules"); 1001 else 1002 { 1003 HOST_WIDE_INT set1 = get_alias_set (TREE_TYPE (TREE_OPERAND (expr, 0))); 1004 HOST_WIDE_INT set2 = get_alias_set (TREE_TYPE (type)); 1005 1006 if (!alias_sets_conflict_p (set1, set2)) 1007 warning (OPT_Wstrict_aliasing, "dereferencing type-punned " 1008 "pointer will break strict-aliasing rules"); 1009 else if (warn_strict_aliasing > 1 1010 && !alias_sets_might_conflict_p (set1, set2)) 1011 warning (OPT_Wstrict_aliasing, "dereferencing type-punned " 1012 "pointer might break strict-aliasing rules"); 1013 } 1014 } 1015} 1016 1017 1018/* Print a warning about if (); or if () .. else; constructs 1019 via the special empty statement node that we create. INNER_THEN 1020 and INNER_ELSE are the statement lists of the if and the else 1021 block. */ 1022 1023void 1024empty_body_warning (tree inner_then, tree inner_else) 1025{ 1026 if (extra_warnings) 1027 { 1028 if (TREE_CODE (inner_then) == STATEMENT_LIST 1029 && STATEMENT_LIST_TAIL (inner_then)) 1030 inner_then = STATEMENT_LIST_TAIL (inner_then)->stmt; 1031 1032 if (inner_else && TREE_CODE (inner_else) == STATEMENT_LIST 1033 && STATEMENT_LIST_TAIL (inner_else)) 1034 inner_else = STATEMENT_LIST_TAIL (inner_else)->stmt; 1035 1036 if (IS_EMPTY_STMT (inner_then) && !inner_else) 1037 warning (OPT_Wextra, "%Hempty body in an if-statement", 1038 EXPR_LOCUS (inner_then)); 1039 1040 if (inner_else && IS_EMPTY_STMT (inner_else)) 1041 warning (OPT_Wextra, "%Hempty body in an else-statement", 1042 EXPR_LOCUS (inner_else)); 1043 } 1044} 1045 1046 1047/* Nonzero if constant C has a value that is permissible 1048 for type TYPE (an INTEGER_TYPE). */ 1049 1050static int 1051constant_fits_type_p (tree c, tree type) 1052{ 1053 if (TREE_CODE (c) == INTEGER_CST) 1054 return int_fits_type_p (c, type); 1055 1056 c = convert (type, c); 1057 return !TREE_OVERFLOW (c); 1058} 1059 1060/* Nonzero if vector types T1 and T2 can be converted to each other 1061 without an explicit cast. */ 1062int 1063vector_types_convertible_p (tree t1, tree t2) 1064{ 1065 return targetm.vector_opaque_p (t1) 1066 || targetm.vector_opaque_p (t2) 1067 || (tree_int_cst_equal (TYPE_SIZE (t1), TYPE_SIZE (t2)) 1068 && (TREE_CODE (TREE_TYPE (t1)) != REAL_TYPE || 1069 TYPE_PRECISION (t1) == TYPE_PRECISION (t2)) 1070 && INTEGRAL_TYPE_P (TREE_TYPE (t1)) 1071 == INTEGRAL_TYPE_P (TREE_TYPE (t2))); 1072} 1073 1074/* Convert EXPR to TYPE, warning about conversion problems with constants. 1075 Invoke this function on every expression that is converted implicitly, 1076 i.e. because of language rules and not because of an explicit cast. */ 1077 1078tree 1079convert_and_check (tree type, tree expr) 1080{ 1081 tree t = convert (type, expr); 1082 if (TREE_CODE (t) == INTEGER_CST) 1083 { 1084 if (TREE_OVERFLOW (t)) 1085 { 1086 TREE_OVERFLOW (t) = 0; 1087 1088 /* Do not diagnose overflow in a constant expression merely 1089 because a conversion overflowed. */ 1090 TREE_CONSTANT_OVERFLOW (t) = CONSTANT_CLASS_P (expr) 1091 && TREE_CONSTANT_OVERFLOW (expr); 1092 1093 /* No warning for converting 0x80000000 to int. */ 1094 if (!(TYPE_UNSIGNED (type) < TYPE_UNSIGNED (TREE_TYPE (expr)) 1095 && TREE_CODE (TREE_TYPE (expr)) == INTEGER_TYPE 1096 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (expr)))) 1097 /* If EXPR fits in the unsigned version of TYPE, 1098 don't warn unless pedantic. */ 1099 if ((pedantic 1100 || TYPE_UNSIGNED (type) 1101 || !constant_fits_type_p (expr, 1102 c_common_unsigned_type (type))) 1103 && skip_evaluation == 0) 1104 warning (OPT_Woverflow, 1105 "overflow in implicit constant conversion"); 1106 } 1107 else 1108 unsigned_conversion_warning (t, expr); 1109 } 1110 return t; 1111} 1112 1113/* A node in a list that describes references to variables (EXPR), which are 1114 either read accesses if WRITER is zero, or write accesses, in which case 1115 WRITER is the parent of EXPR. */ 1116struct tlist 1117{ 1118 struct tlist *next; 1119 tree expr, writer; 1120}; 1121 1122/* Used to implement a cache the results of a call to verify_tree. We only 1123 use this for SAVE_EXPRs. */ 1124struct tlist_cache 1125{ 1126 struct tlist_cache *next; 1127 struct tlist *cache_before_sp; 1128 struct tlist *cache_after_sp; 1129 tree expr; 1130}; 1131 1132/* Obstack to use when allocating tlist structures, and corresponding 1133 firstobj. */ 1134static struct obstack tlist_obstack; 1135static char *tlist_firstobj = 0; 1136 1137/* Keep track of the identifiers we've warned about, so we can avoid duplicate 1138 warnings. */ 1139static struct tlist *warned_ids; 1140/* SAVE_EXPRs need special treatment. We process them only once and then 1141 cache the results. */ 1142static struct tlist_cache *save_expr_cache; 1143 1144static void add_tlist (struct tlist **, struct tlist *, tree, int); 1145static void merge_tlist (struct tlist **, struct tlist *, int); 1146static void verify_tree (tree, struct tlist **, struct tlist **, tree); 1147static int warning_candidate_p (tree); 1148static void warn_for_collisions (struct tlist *); 1149static void warn_for_collisions_1 (tree, tree, struct tlist *, int); 1150static struct tlist *new_tlist (struct tlist *, tree, tree); 1151 1152/* Create a new struct tlist and fill in its fields. */ 1153static struct tlist * 1154new_tlist (struct tlist *next, tree t, tree writer) 1155{ 1156 struct tlist *l; 1157 l = XOBNEW (&tlist_obstack, struct tlist); 1158 l->next = next; 1159 l->expr = t; 1160 l->writer = writer; 1161 return l; 1162} 1163 1164/* Add duplicates of the nodes found in ADD to the list *TO. If EXCLUDE_WRITER 1165 is nonnull, we ignore any node we find which has a writer equal to it. */ 1166 1167static void 1168add_tlist (struct tlist **to, struct tlist *add, tree exclude_writer, int copy) 1169{ 1170 while (add) 1171 { 1172 struct tlist *next = add->next; 1173 if (!copy) 1174 add->next = *to; 1175 if (!exclude_writer || add->writer != exclude_writer) 1176 *to = copy ? new_tlist (*to, add->expr, add->writer) : add; 1177 add = next; 1178 } 1179} 1180 1181/* Merge the nodes of ADD into TO. This merging process is done so that for 1182 each variable that already exists in TO, no new node is added; however if 1183 there is a write access recorded in ADD, and an occurrence on TO is only 1184 a read access, then the occurrence in TO will be modified to record the 1185 write. */ 1186 1187static void 1188merge_tlist (struct tlist **to, struct tlist *add, int copy) 1189{ 1190 struct tlist **end = to; 1191 1192 while (*end) 1193 end = &(*end)->next; 1194 1195 while (add) 1196 { 1197 int found = 0; 1198 struct tlist *tmp2; 1199 struct tlist *next = add->next; 1200 1201 for (tmp2 = *to; tmp2; tmp2 = tmp2->next) 1202 if (tmp2->expr == add->expr) 1203 { 1204 found = 1; 1205 if (!tmp2->writer) 1206 tmp2->writer = add->writer; 1207 } 1208 if (!found) 1209 { 1210 *end = copy ? add : new_tlist (NULL, add->expr, add->writer); 1211 end = &(*end)->next; 1212 *end = 0; 1213 } 1214 add = next; 1215 } 1216} 1217 1218/* WRITTEN is a variable, WRITER is its parent. Warn if any of the variable 1219 references in list LIST conflict with it, excluding reads if ONLY writers 1220 is nonzero. */ 1221 1222static void 1223warn_for_collisions_1 (tree written, tree writer, struct tlist *list, 1224 int only_writes) 1225{ 1226 struct tlist *tmp; 1227 1228 /* Avoid duplicate warnings. */ 1229 for (tmp = warned_ids; tmp; tmp = tmp->next) 1230 if (tmp->expr == written) 1231 return; 1232 1233 while (list) 1234 { 1235 if (list->expr == written 1236 && list->writer != writer 1237 && (!only_writes || list->writer) 1238 && DECL_NAME (list->expr)) 1239 { 1240 warned_ids = new_tlist (warned_ids, written, NULL_TREE); 1241 warning (0, "operation on %qE may be undefined", list->expr); 1242 } 1243 list = list->next; 1244 } 1245} 1246 1247/* Given a list LIST of references to variables, find whether any of these 1248 can cause conflicts due to missing sequence points. */ 1249 1250static void 1251warn_for_collisions (struct tlist *list) 1252{ 1253 struct tlist *tmp; 1254 1255 for (tmp = list; tmp; tmp = tmp->next) 1256 { 1257 if (tmp->writer) 1258 warn_for_collisions_1 (tmp->expr, tmp->writer, list, 0); 1259 } 1260} 1261 1262/* Return nonzero if X is a tree that can be verified by the sequence point 1263 warnings. */ 1264static int 1265warning_candidate_p (tree x) 1266{ 1267 return TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == PARM_DECL; 1268} 1269 1270/* Walk the tree X, and record accesses to variables. If X is written by the 1271 parent tree, WRITER is the parent. 1272 We store accesses in one of the two lists: PBEFORE_SP, and PNO_SP. If this 1273 expression or its only operand forces a sequence point, then everything up 1274 to the sequence point is stored in PBEFORE_SP. Everything else gets stored 1275 in PNO_SP. 1276 Once we return, we will have emitted warnings if any subexpression before 1277 such a sequence point could be undefined. On a higher level, however, the 1278 sequence point may not be relevant, and we'll merge the two lists. 1279 1280 Example: (b++, a) + b; 1281 The call that processes the COMPOUND_EXPR will store the increment of B 1282 in PBEFORE_SP, and the use of A in PNO_SP. The higher-level call that 1283 processes the PLUS_EXPR will need to merge the two lists so that 1284 eventually, all accesses end up on the same list (and we'll warn about the 1285 unordered subexpressions b++ and b. 1286 1287 A note on merging. If we modify the former example so that our expression 1288 becomes 1289 (b++, b) + a 1290 care must be taken not simply to add all three expressions into the final 1291 PNO_SP list. The function merge_tlist takes care of that by merging the 1292 before-SP list of the COMPOUND_EXPR into its after-SP list in a special 1293 way, so that no more than one access to B is recorded. */ 1294 1295static void 1296verify_tree (tree x, struct tlist **pbefore_sp, struct tlist **pno_sp, 1297 tree writer) 1298{ 1299 struct tlist *tmp_before, *tmp_nosp, *tmp_list2, *tmp_list3; 1300 enum tree_code code; 1301 enum tree_code_class cl; 1302 1303 /* X may be NULL if it is the operand of an empty statement expression 1304 ({ }). */ 1305 if (x == NULL) 1306 return; 1307 1308 restart: 1309 code = TREE_CODE (x); 1310 cl = TREE_CODE_CLASS (code); 1311 1312 if (warning_candidate_p (x)) 1313 { 1314 *pno_sp = new_tlist (*pno_sp, x, writer); 1315 return; 1316 } 1317 1318 switch (code) 1319 { 1320 case CONSTRUCTOR: 1321 return; 1322 1323 case COMPOUND_EXPR: 1324 case TRUTH_ANDIF_EXPR: 1325 case TRUTH_ORIF_EXPR: 1326 tmp_before = tmp_nosp = tmp_list3 = 0; 1327 verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE); 1328 warn_for_collisions (tmp_nosp); 1329 merge_tlist (pbefore_sp, tmp_before, 0); 1330 merge_tlist (pbefore_sp, tmp_nosp, 0); 1331 verify_tree (TREE_OPERAND (x, 1), &tmp_list3, pno_sp, NULL_TREE); 1332 merge_tlist (pbefore_sp, tmp_list3, 0); 1333 return; 1334 1335 case COND_EXPR: 1336 tmp_before = tmp_list2 = 0; 1337 verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_list2, NULL_TREE); 1338 warn_for_collisions (tmp_list2); 1339 merge_tlist (pbefore_sp, tmp_before, 0); 1340 merge_tlist (pbefore_sp, tmp_list2, 1); 1341 1342 tmp_list3 = tmp_nosp = 0; 1343 verify_tree (TREE_OPERAND (x, 1), &tmp_list3, &tmp_nosp, NULL_TREE); 1344 warn_for_collisions (tmp_nosp); 1345 merge_tlist (pbefore_sp, tmp_list3, 0); 1346 1347 tmp_list3 = tmp_list2 = 0; 1348 verify_tree (TREE_OPERAND (x, 2), &tmp_list3, &tmp_list2, NULL_TREE); 1349 warn_for_collisions (tmp_list2); 1350 merge_tlist (pbefore_sp, tmp_list3, 0); 1351 /* Rather than add both tmp_nosp and tmp_list2, we have to merge the 1352 two first, to avoid warning for (a ? b++ : b++). */ 1353 merge_tlist (&tmp_nosp, tmp_list2, 0); 1354 add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0); 1355 return; 1356 1357 case PREDECREMENT_EXPR: 1358 case PREINCREMENT_EXPR: 1359 case POSTDECREMENT_EXPR: 1360 case POSTINCREMENT_EXPR: 1361 verify_tree (TREE_OPERAND (x, 0), pno_sp, pno_sp, x); 1362 return; 1363 1364 case MODIFY_EXPR: 1365 tmp_before = tmp_nosp = tmp_list3 = 0; 1366 verify_tree (TREE_OPERAND (x, 1), &tmp_before, &tmp_nosp, NULL_TREE); 1367 verify_tree (TREE_OPERAND (x, 0), &tmp_list3, &tmp_list3, x); 1368 /* Expressions inside the LHS are not ordered wrt. the sequence points 1369 in the RHS. Example: 1370 *a = (a++, 2) 1371 Despite the fact that the modification of "a" is in the before_sp 1372 list (tmp_before), it conflicts with the use of "a" in the LHS. 1373 We can handle this by adding the contents of tmp_list3 1374 to those of tmp_before, and redoing the collision warnings for that 1375 list. */ 1376 add_tlist (&tmp_before, tmp_list3, x, 1); 1377 warn_for_collisions (tmp_before); 1378 /* Exclude the LHS itself here; we first have to merge it into the 1379 tmp_nosp list. This is done to avoid warning for "a = a"; if we 1380 didn't exclude the LHS, we'd get it twice, once as a read and once 1381 as a write. */ 1382 add_tlist (pno_sp, tmp_list3, x, 0); 1383 warn_for_collisions_1 (TREE_OPERAND (x, 0), x, tmp_nosp, 1); 1384 1385 merge_tlist (pbefore_sp, tmp_before, 0); 1386 if (warning_candidate_p (TREE_OPERAND (x, 0))) 1387 merge_tlist (&tmp_nosp, new_tlist (NULL, TREE_OPERAND (x, 0), x), 0); 1388 add_tlist (pno_sp, tmp_nosp, NULL_TREE, 1); 1389 return; 1390 1391 case CALL_EXPR: 1392 /* We need to warn about conflicts among arguments and conflicts between 1393 args and the function address. Side effects of the function address, 1394 however, are not ordered by the sequence point of the call. */ 1395 tmp_before = tmp_nosp = tmp_list2 = tmp_list3 = 0; 1396 verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE); 1397 if (TREE_OPERAND (x, 1)) 1398 verify_tree (TREE_OPERAND (x, 1), &tmp_list2, &tmp_list3, NULL_TREE); 1399 merge_tlist (&tmp_list3, tmp_list2, 0); 1400 add_tlist (&tmp_before, tmp_list3, NULL_TREE, 0); 1401 add_tlist (&tmp_before, tmp_nosp, NULL_TREE, 0); 1402 warn_for_collisions (tmp_before); 1403 add_tlist (pbefore_sp, tmp_before, NULL_TREE, 0); 1404 return; 1405 1406 case TREE_LIST: 1407 /* Scan all the list, e.g. indices of multi dimensional array. */ 1408 while (x) 1409 { 1410 tmp_before = tmp_nosp = 0; 1411 verify_tree (TREE_VALUE (x), &tmp_before, &tmp_nosp, NULL_TREE); 1412 merge_tlist (&tmp_nosp, tmp_before, 0); 1413 add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0); 1414 x = TREE_CHAIN (x); 1415 } 1416 return; 1417 1418 case SAVE_EXPR: 1419 { 1420 struct tlist_cache *t; 1421 for (t = save_expr_cache; t; t = t->next) 1422 if (t->expr == x) 1423 break; 1424 1425 if (!t) 1426 { 1427 t = XOBNEW (&tlist_obstack, struct tlist_cache); 1428 t->next = save_expr_cache; 1429 t->expr = x; 1430 save_expr_cache = t; 1431 1432 tmp_before = tmp_nosp = 0; 1433 verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE); 1434 warn_for_collisions (tmp_nosp); 1435 1436 tmp_list3 = 0; 1437 while (tmp_nosp) 1438 { 1439 struct tlist *t = tmp_nosp; 1440 tmp_nosp = t->next; 1441 merge_tlist (&tmp_list3, t, 0); 1442 } 1443 t->cache_before_sp = tmp_before; 1444 t->cache_after_sp = tmp_list3; 1445 } 1446 merge_tlist (pbefore_sp, t->cache_before_sp, 1); 1447 add_tlist (pno_sp, t->cache_after_sp, NULL_TREE, 1); 1448 return; 1449 } 1450 1451 default: 1452 /* For other expressions, simply recurse on their operands. 1453 Manual tail recursion for unary expressions. 1454 Other non-expressions need not be processed. */ 1455 if (cl == tcc_unary) 1456 { 1457 x = TREE_OPERAND (x, 0); 1458 writer = 0; 1459 goto restart; 1460 } 1461 else if (IS_EXPR_CODE_CLASS (cl)) 1462 { 1463 int lp; 1464 int max = TREE_CODE_LENGTH (TREE_CODE (x)); 1465 for (lp = 0; lp < max; lp++) 1466 { 1467 tmp_before = tmp_nosp = 0; 1468 verify_tree (TREE_OPERAND (x, lp), &tmp_before, &tmp_nosp, 0); 1469 merge_tlist (&tmp_nosp, tmp_before, 0); 1470 add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0); 1471 } 1472 } 1473 return; 1474 } 1475} 1476 1477/* Try to warn for undefined behavior in EXPR due to missing sequence 1478 points. */ 1479 1480void 1481verify_sequence_points (tree expr) 1482{ 1483 struct tlist *before_sp = 0, *after_sp = 0; 1484 1485 warned_ids = 0; 1486 save_expr_cache = 0; 1487 if (tlist_firstobj == 0) 1488 { 1489 gcc_obstack_init (&tlist_obstack); 1490 tlist_firstobj = (char *) obstack_alloc (&tlist_obstack, 0); 1491 } 1492 1493 verify_tree (expr, &before_sp, &after_sp, 0); 1494 warn_for_collisions (after_sp); 1495 obstack_free (&tlist_obstack, tlist_firstobj); 1496} 1497 1498/* Validate the expression after `case' and apply default promotions. */ 1499 1500static tree 1501check_case_value (tree value) 1502{ 1503 if (value == NULL_TREE) 1504 return value; 1505 1506 /* ??? Can we ever get nops here for a valid case value? We 1507 shouldn't for C. */ 1508 STRIP_TYPE_NOPS (value); 1509 /* In C++, the following is allowed: 1510 1511 const int i = 3; 1512 switch (...) { case i: ... } 1513 1514 So, we try to reduce the VALUE to a constant that way. */ 1515 if (c_dialect_cxx ()) 1516 { 1517 value = decl_constant_value (value); 1518 STRIP_TYPE_NOPS (value); 1519 value = fold (value); 1520 } 1521 1522 if (TREE_CODE (value) == INTEGER_CST) 1523 /* Promote char or short to int. */ 1524 value = perform_integral_promotions (value); 1525 else if (value != error_mark_node) 1526 { 1527 error ("case label does not reduce to an integer constant"); 1528 value = error_mark_node; 1529 } 1530 1531 constant_expression_warning (value); 1532 1533 return value; 1534} 1535 1536/* See if the case values LOW and HIGH are in the range of the original 1537 type (i.e. before the default conversion to int) of the switch testing 1538 expression. 1539 TYPE is the promoted type of the testing expression, and ORIG_TYPE is 1540 the type before promoting it. CASE_LOW_P is a pointer to the lower 1541 bound of the case label, and CASE_HIGH_P is the upper bound or NULL 1542 if the case is not a case range. 1543 The caller has to make sure that we are not called with NULL for 1544 CASE_LOW_P (i.e. the default case). 1545 Returns true if the case label is in range of ORIG_TYPE (saturated or 1546 untouched) or false if the label is out of range. */ 1547 1548static bool 1549check_case_bounds (tree type, tree orig_type, 1550 tree *case_low_p, tree *case_high_p) 1551{ 1552 tree min_value, max_value; 1553 tree case_low = *case_low_p; 1554 tree case_high = case_high_p ? *case_high_p : case_low; 1555 1556 /* If there was a problem with the original type, do nothing. */ 1557 if (orig_type == error_mark_node) 1558 return true; 1559 1560 min_value = TYPE_MIN_VALUE (orig_type); 1561 max_value = TYPE_MAX_VALUE (orig_type); 1562 1563 /* Case label is less than minimum for type. */ 1564 if (tree_int_cst_compare (case_low, min_value) < 0 1565 && tree_int_cst_compare (case_high, min_value) < 0) 1566 { 1567 warning (0, "case label value is less than minimum value for type"); 1568 return false; 1569 } 1570 1571 /* Case value is greater than maximum for type. */ 1572 if (tree_int_cst_compare (case_low, max_value) > 0 1573 && tree_int_cst_compare (case_high, max_value) > 0) 1574 { 1575 warning (0, "case label value exceeds maximum value for type"); 1576 return false; 1577 } 1578 1579 /* Saturate lower case label value to minimum. */ 1580 if (tree_int_cst_compare (case_high, min_value) >= 0 1581 && tree_int_cst_compare (case_low, min_value) < 0) 1582 { 1583 warning (0, "lower value in case label range" 1584 " less than minimum value for type"); 1585 case_low = min_value; 1586 } 1587 1588 /* Saturate upper case label value to maximum. */ 1589 if (tree_int_cst_compare (case_low, max_value) <= 0 1590 && tree_int_cst_compare (case_high, max_value) > 0) 1591 { 1592 warning (0, "upper value in case label range" 1593 " exceeds maximum value for type"); 1594 case_high = max_value; 1595 } 1596 1597 if (*case_low_p != case_low) 1598 *case_low_p = convert (type, case_low); 1599 if (case_high_p && *case_high_p != case_high) 1600 *case_high_p = convert (type, case_high); 1601 1602 return true; 1603} 1604 1605/* Return an integer type with BITS bits of precision, 1606 that is unsigned if UNSIGNEDP is nonzero, otherwise signed. */ 1607 1608tree 1609c_common_type_for_size (unsigned int bits, int unsignedp) 1610{ 1611 if (bits == TYPE_PRECISION (integer_type_node)) 1612 return unsignedp ? unsigned_type_node : integer_type_node; 1613 1614 if (bits == TYPE_PRECISION (signed_char_type_node)) 1615 return unsignedp ? unsigned_char_type_node : signed_char_type_node; 1616 1617 if (bits == TYPE_PRECISION (short_integer_type_node)) 1618 return unsignedp ? short_unsigned_type_node : short_integer_type_node; 1619 1620 if (bits == TYPE_PRECISION (long_integer_type_node)) 1621 return unsignedp ? long_unsigned_type_node : long_integer_type_node; 1622 1623 if (bits == TYPE_PRECISION (long_long_integer_type_node)) 1624 return (unsignedp ? long_long_unsigned_type_node 1625 : long_long_integer_type_node); 1626 1627 if (bits == TYPE_PRECISION (widest_integer_literal_type_node)) 1628 return (unsignedp ? widest_unsigned_literal_type_node 1629 : widest_integer_literal_type_node); 1630 1631 if (bits <= TYPE_PRECISION (intQI_type_node)) 1632 return unsignedp ? unsigned_intQI_type_node : intQI_type_node; 1633 1634 if (bits <= TYPE_PRECISION (intHI_type_node)) 1635 return unsignedp ? unsigned_intHI_type_node : intHI_type_node; 1636 1637 if (bits <= TYPE_PRECISION (intSI_type_node)) 1638 return unsignedp ? unsigned_intSI_type_node : intSI_type_node; 1639 1640 if (bits <= TYPE_PRECISION (intDI_type_node)) 1641 return unsignedp ? unsigned_intDI_type_node : intDI_type_node; 1642 1643 return 0; 1644} 1645 1646/* Used for communication between c_common_type_for_mode and 1647 c_register_builtin_type. */ 1648static GTY(()) tree registered_builtin_types; 1649 1650/* Return a data type that has machine mode MODE. 1651 If the mode is an integer, 1652 then UNSIGNEDP selects between signed and unsigned types. */ 1653 1654tree 1655c_common_type_for_mode (enum machine_mode mode, int unsignedp) 1656{ 1657 tree t; 1658 1659 if (mode == TYPE_MODE (integer_type_node)) 1660 return unsignedp ? unsigned_type_node : integer_type_node; 1661 1662 if (mode == TYPE_MODE (signed_char_type_node)) 1663 return unsignedp ? unsigned_char_type_node : signed_char_type_node; 1664 1665 if (mode == TYPE_MODE (short_integer_type_node)) 1666 return unsignedp ? short_unsigned_type_node : short_integer_type_node; 1667 1668 if (mode == TYPE_MODE (long_integer_type_node)) 1669 return unsignedp ? long_unsigned_type_node : long_integer_type_node; 1670 1671 if (mode == TYPE_MODE (long_long_integer_type_node)) 1672 return unsignedp ? long_long_unsigned_type_node : long_long_integer_type_node; 1673 1674 if (mode == TYPE_MODE (widest_integer_literal_type_node)) 1675 return unsignedp ? widest_unsigned_literal_type_node 1676 : widest_integer_literal_type_node; 1677 1678 if (mode == QImode) 1679 return unsignedp ? unsigned_intQI_type_node : intQI_type_node; 1680 1681 if (mode == HImode) 1682 return unsignedp ? unsigned_intHI_type_node : intHI_type_node; 1683 1684 if (mode == SImode) 1685 return unsignedp ? unsigned_intSI_type_node : intSI_type_node; 1686 1687 if (mode == DImode) 1688 return unsignedp ? unsigned_intDI_type_node : intDI_type_node; 1689 1690#if HOST_BITS_PER_WIDE_INT >= 64 1691 if (mode == TYPE_MODE (intTI_type_node)) 1692 return unsignedp ? unsigned_intTI_type_node : intTI_type_node; 1693#endif 1694 1695 if (mode == TYPE_MODE (float_type_node)) 1696 return float_type_node; 1697 1698 if (mode == TYPE_MODE (double_type_node)) 1699 return double_type_node; 1700 1701 if (mode == TYPE_MODE (long_double_type_node)) 1702 return long_double_type_node; 1703 1704 if (mode == TYPE_MODE (void_type_node)) 1705 return void_type_node; 1706 1707 if (mode == TYPE_MODE (build_pointer_type (char_type_node))) 1708 return (unsignedp 1709 ? make_unsigned_type (GET_MODE_PRECISION (mode)) 1710 : make_signed_type (GET_MODE_PRECISION (mode))); 1711 1712 if (mode == TYPE_MODE (build_pointer_type (integer_type_node))) 1713 return (unsignedp 1714 ? make_unsigned_type (GET_MODE_PRECISION (mode)) 1715 : make_signed_type (GET_MODE_PRECISION (mode))); 1716 1717 if (COMPLEX_MODE_P (mode)) 1718 { 1719 enum machine_mode inner_mode; 1720 tree inner_type; 1721 1722 if (mode == TYPE_MODE (complex_float_type_node)) 1723 return complex_float_type_node; 1724 if (mode == TYPE_MODE (complex_double_type_node)) 1725 return complex_double_type_node; 1726 if (mode == TYPE_MODE (complex_long_double_type_node)) 1727 return complex_long_double_type_node; 1728 1729 if (mode == TYPE_MODE (complex_integer_type_node) && !unsignedp) 1730 return complex_integer_type_node; 1731 1732 inner_mode = GET_MODE_INNER (mode); 1733 inner_type = c_common_type_for_mode (inner_mode, unsignedp); 1734 if (inner_type != NULL_TREE) 1735 return build_complex_type (inner_type); 1736 } 1737 else if (VECTOR_MODE_P (mode)) 1738 { 1739 enum machine_mode inner_mode = GET_MODE_INNER (mode); 1740 tree inner_type = c_common_type_for_mode (inner_mode, unsignedp); 1741 if (inner_type != NULL_TREE) 1742 return build_vector_type_for_mode (inner_type, mode); 1743 } 1744 1745 if (mode == TYPE_MODE (dfloat32_type_node)) 1746 return dfloat32_type_node; 1747 if (mode == TYPE_MODE (dfloat64_type_node)) 1748 return dfloat64_type_node; 1749 if (mode == TYPE_MODE (dfloat128_type_node)) 1750 return dfloat128_type_node; 1751 1752 for (t = registered_builtin_types; t; t = TREE_CHAIN (t)) 1753 if (TYPE_MODE (TREE_VALUE (t)) == mode) 1754 return TREE_VALUE (t); 1755 1756 return 0; 1757} 1758 1759/* Return an unsigned type the same as TYPE in other respects. */ 1760tree 1761c_common_unsigned_type (tree type) 1762{ 1763 tree type1 = TYPE_MAIN_VARIANT (type); 1764 if (type1 == signed_char_type_node || type1 == char_type_node) 1765 return unsigned_char_type_node; 1766 if (type1 == integer_type_node) 1767 return unsigned_type_node; 1768 if (type1 == short_integer_type_node) 1769 return short_unsigned_type_node; 1770 if (type1 == long_integer_type_node) 1771 return long_unsigned_type_node; 1772 if (type1 == long_long_integer_type_node) 1773 return long_long_unsigned_type_node; 1774 if (type1 == widest_integer_literal_type_node) 1775 return widest_unsigned_literal_type_node; 1776#if HOST_BITS_PER_WIDE_INT >= 64 1777 if (type1 == intTI_type_node) 1778 return unsigned_intTI_type_node; 1779#endif 1780 if (type1 == intDI_type_node) 1781 return unsigned_intDI_type_node; 1782 if (type1 == intSI_type_node) 1783 return unsigned_intSI_type_node; 1784 if (type1 == intHI_type_node) 1785 return unsigned_intHI_type_node; 1786 if (type1 == intQI_type_node) 1787 return unsigned_intQI_type_node; 1788 1789 return c_common_signed_or_unsigned_type (1, type); 1790} 1791 1792/* Return a signed type the same as TYPE in other respects. */ 1793 1794tree 1795c_common_signed_type (tree type) 1796{ 1797 tree type1 = TYPE_MAIN_VARIANT (type); 1798 if (type1 == unsigned_char_type_node || type1 == char_type_node) 1799 return signed_char_type_node; 1800 if (type1 == unsigned_type_node) 1801 return integer_type_node; 1802 if (type1 == short_unsigned_type_node) 1803 return short_integer_type_node; 1804 if (type1 == long_unsigned_type_node) 1805 return long_integer_type_node; 1806 if (type1 == long_long_unsigned_type_node) 1807 return long_long_integer_type_node; 1808 if (type1 == widest_unsigned_literal_type_node) 1809 return widest_integer_literal_type_node; 1810#if HOST_BITS_PER_WIDE_INT >= 64 1811 if (type1 == unsigned_intTI_type_node) 1812 return intTI_type_node; 1813#endif 1814 if (type1 == unsigned_intDI_type_node) 1815 return intDI_type_node; 1816 if (type1 == unsigned_intSI_type_node) 1817 return intSI_type_node; 1818 if (type1 == unsigned_intHI_type_node) 1819 return intHI_type_node; 1820 if (type1 == unsigned_intQI_type_node) 1821 return intQI_type_node; 1822 1823 return c_common_signed_or_unsigned_type (0, type); 1824} 1825 1826/* Return a type the same as TYPE except unsigned or 1827 signed according to UNSIGNEDP. */ 1828 1829tree 1830c_common_signed_or_unsigned_type (int unsignedp, tree type) 1831{ 1832 if (!INTEGRAL_TYPE_P (type) 1833 || TYPE_UNSIGNED (type) == unsignedp) 1834 return type; 1835 1836 /* For ENUMERAL_TYPEs in C++, must check the mode of the types, not 1837 the precision; they have precision set to match their range, but 1838 may use a wider mode to match an ABI. If we change modes, we may 1839 wind up with bad conversions. For INTEGER_TYPEs in C, must check 1840 the precision as well, so as to yield correct results for 1841 bit-field types. C++ does not have these separate bit-field 1842 types, and producing a signed or unsigned variant of an 1843 ENUMERAL_TYPE may cause other problems as well. */ 1844 1845#define TYPE_OK(node) \ 1846 (TYPE_MODE (type) == TYPE_MODE (node) \ 1847 && (c_dialect_cxx () || TYPE_PRECISION (type) == TYPE_PRECISION (node))) 1848 if (TYPE_OK (signed_char_type_node)) 1849 return unsignedp ? unsigned_char_type_node : signed_char_type_node; 1850 if (TYPE_OK (integer_type_node)) 1851 return unsignedp ? unsigned_type_node : integer_type_node; 1852 if (TYPE_OK (short_integer_type_node)) 1853 return unsignedp ? short_unsigned_type_node : short_integer_type_node; 1854 if (TYPE_OK (long_integer_type_node)) 1855 return unsignedp ? long_unsigned_type_node : long_integer_type_node; 1856 if (TYPE_OK (long_long_integer_type_node)) 1857 return (unsignedp ? long_long_unsigned_type_node 1858 : long_long_integer_type_node); 1859 if (TYPE_OK (widest_integer_literal_type_node)) 1860 return (unsignedp ? widest_unsigned_literal_type_node 1861 : widest_integer_literal_type_node); 1862 1863#if HOST_BITS_PER_WIDE_INT >= 64 1864 if (TYPE_OK (intTI_type_node)) 1865 return unsignedp ? unsigned_intTI_type_node : intTI_type_node; 1866#endif 1867 if (TYPE_OK (intDI_type_node)) 1868 return unsignedp ? unsigned_intDI_type_node : intDI_type_node; 1869 if (TYPE_OK (intSI_type_node)) 1870 return unsignedp ? unsigned_intSI_type_node : intSI_type_node; 1871 if (TYPE_OK (intHI_type_node)) 1872 return unsignedp ? unsigned_intHI_type_node : intHI_type_node; 1873 if (TYPE_OK (intQI_type_node)) 1874 return unsignedp ? unsigned_intQI_type_node : intQI_type_node; 1875#undef TYPE_OK 1876 1877 if (c_dialect_cxx ()) 1878 return type; 1879 else 1880 return build_nonstandard_integer_type (TYPE_PRECISION (type), unsignedp); 1881} 1882 1883/* Build a bit-field integer type for the given WIDTH and UNSIGNEDP. */ 1884 1885tree 1886c_build_bitfield_integer_type (unsigned HOST_WIDE_INT width, int unsignedp) 1887{ 1888 /* Extended integer types of the same width as a standard type have 1889 lesser rank, so those of the same width as int promote to int or 1890 unsigned int and are valid for printf formats expecting int or 1891 unsigned int. To avoid such special cases, avoid creating 1892 extended integer types for bit-fields if a standard integer type 1893 is available. */ 1894 if (width == TYPE_PRECISION (integer_type_node)) 1895 return unsignedp ? unsigned_type_node : integer_type_node; 1896 if (width == TYPE_PRECISION (signed_char_type_node)) 1897 return unsignedp ? unsigned_char_type_node : signed_char_type_node; 1898 if (width == TYPE_PRECISION (short_integer_type_node)) 1899 return unsignedp ? short_unsigned_type_node : short_integer_type_node; 1900 if (width == TYPE_PRECISION (long_integer_type_node)) 1901 return unsignedp ? long_unsigned_type_node : long_integer_type_node; 1902 if (width == TYPE_PRECISION (long_long_integer_type_node)) 1903 return (unsignedp ? long_long_unsigned_type_node 1904 : long_long_integer_type_node); 1905 return build_nonstandard_integer_type (width, unsignedp); 1906} 1907 1908/* The C version of the register_builtin_type langhook. */ 1909 1910void 1911c_register_builtin_type (tree type, const char* name) 1912{ 1913 tree decl; 1914 1915 decl = build_decl (TYPE_DECL, get_identifier (name), type); 1916 DECL_ARTIFICIAL (decl) = 1; 1917 if (!TYPE_NAME (type)) 1918 TYPE_NAME (type) = decl; 1919 pushdecl (decl); 1920 1921 registered_builtin_types = tree_cons (0, type, registered_builtin_types); 1922} 1923 1924 1925/* Return the minimum number of bits needed to represent VALUE in a 1926 signed or unsigned type, UNSIGNEDP says which. */ 1927 1928unsigned int 1929min_precision (tree value, int unsignedp) 1930{ 1931 int log; 1932 1933 /* If the value is negative, compute its negative minus 1. The latter 1934 adjustment is because the absolute value of the largest negative value 1935 is one larger than the largest positive value. This is equivalent to 1936 a bit-wise negation, so use that operation instead. */ 1937 1938 if (tree_int_cst_sgn (value) < 0) 1939 value = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (value), value); 1940 1941 /* Return the number of bits needed, taking into account the fact 1942 that we need one more bit for a signed than unsigned type. */ 1943 1944 if (integer_zerop (value)) 1945 log = 0; 1946 else 1947 log = tree_floor_log2 (value); 1948 1949 return log + 1 + !unsignedp; 1950} 1951 1952/* Print an error message for invalid operands to arith operation 1953 CODE. */ 1954 1955void 1956binary_op_error (enum tree_code code) 1957{ 1958 const char *opname; 1959 1960 switch (code) 1961 { 1962 case PLUS_EXPR: 1963 opname = "+"; break; 1964 case MINUS_EXPR: 1965 opname = "-"; break; 1966 case MULT_EXPR: 1967 opname = "*"; break; 1968 case MAX_EXPR: 1969 opname = "max"; break; 1970 case MIN_EXPR: 1971 opname = "min"; break; 1972 case EQ_EXPR: 1973 opname = "=="; break; 1974 case NE_EXPR: 1975 opname = "!="; break; 1976 case LE_EXPR: 1977 opname = "<="; break; 1978 case GE_EXPR: 1979 opname = ">="; break; 1980 case LT_EXPR: 1981 opname = "<"; break; 1982 case GT_EXPR: 1983 opname = ">"; break; 1984 case LSHIFT_EXPR: 1985 opname = "<<"; break; 1986 case RSHIFT_EXPR: 1987 opname = ">>"; break; 1988 case TRUNC_MOD_EXPR: 1989 case FLOOR_MOD_EXPR: 1990 opname = "%"; break; 1991 case TRUNC_DIV_EXPR: 1992 case FLOOR_DIV_EXPR: 1993 opname = "/"; break; 1994 case BIT_AND_EXPR: 1995 opname = "&"; break; 1996 case BIT_IOR_EXPR: 1997 opname = "|"; break; 1998 case TRUTH_ANDIF_EXPR: 1999 opname = "&&"; break; 2000 case TRUTH_ORIF_EXPR: 2001 opname = "||"; break; 2002 case BIT_XOR_EXPR: 2003 opname = "^"; break; 2004 default: 2005 gcc_unreachable (); 2006 } 2007 error ("invalid operands to binary %s", opname); 2008} 2009 2010/* Subroutine of build_binary_op, used for comparison operations. 2011 See if the operands have both been converted from subword integer types 2012 and, if so, perhaps change them both back to their original type. 2013 This function is also responsible for converting the two operands 2014 to the proper common type for comparison. 2015 2016 The arguments of this function are all pointers to local variables 2017 of build_binary_op: OP0_PTR is &OP0, OP1_PTR is &OP1, 2018 RESTYPE_PTR is &RESULT_TYPE and RESCODE_PTR is &RESULTCODE. 2019 2020 If this function returns nonzero, it means that the comparison has 2021 a constant value. What this function returns is an expression for 2022 that value. */ 2023 2024tree 2025shorten_compare (tree *op0_ptr, tree *op1_ptr, tree *restype_ptr, 2026 enum tree_code *rescode_ptr) 2027{ 2028 tree type; 2029 tree op0 = *op0_ptr; 2030 tree op1 = *op1_ptr; 2031 int unsignedp0, unsignedp1; 2032 int real1, real2; 2033 tree primop0, primop1; 2034 enum tree_code code = *rescode_ptr; 2035 2036 /* Throw away any conversions to wider types 2037 already present in the operands. */ 2038 2039 primop0 = get_narrower (op0, &unsignedp0); 2040 primop1 = get_narrower (op1, &unsignedp1); 2041 2042 /* Handle the case that OP0 does not *contain* a conversion 2043 but it *requires* conversion to FINAL_TYPE. */ 2044 2045 if (op0 == primop0 && TREE_TYPE (op0) != *restype_ptr) 2046 unsignedp0 = TYPE_UNSIGNED (TREE_TYPE (op0)); 2047 if (op1 == primop1 && TREE_TYPE (op1) != *restype_ptr) 2048 unsignedp1 = TYPE_UNSIGNED (TREE_TYPE (op1)); 2049 2050 /* If one of the operands must be floated, we cannot optimize. */ 2051 real1 = TREE_CODE (TREE_TYPE (primop0)) == REAL_TYPE; 2052 real2 = TREE_CODE (TREE_TYPE (primop1)) == REAL_TYPE; 2053 2054 /* If first arg is constant, swap the args (changing operation 2055 so value is preserved), for canonicalization. Don't do this if 2056 the second arg is 0. */ 2057 2058 if (TREE_CONSTANT (primop0) 2059 && !integer_zerop (primop1) && !real_zerop (primop1)) 2060 { 2061 tree tem = primop0; 2062 int temi = unsignedp0; 2063 primop0 = primop1; 2064 primop1 = tem; 2065 tem = op0; 2066 op0 = op1; 2067 op1 = tem; 2068 *op0_ptr = op0; 2069 *op1_ptr = op1; 2070 unsignedp0 = unsignedp1; 2071 unsignedp1 = temi; 2072 temi = real1; 2073 real1 = real2; 2074 real2 = temi; 2075 2076 switch (code) 2077 { 2078 case LT_EXPR: 2079 code = GT_EXPR; 2080 break; 2081 case GT_EXPR: 2082 code = LT_EXPR; 2083 break; 2084 case LE_EXPR: 2085 code = GE_EXPR; 2086 break; 2087 case GE_EXPR: 2088 code = LE_EXPR; 2089 break; 2090 default: 2091 break; 2092 } 2093 *rescode_ptr = code; 2094 } 2095 2096 /* If comparing an integer against a constant more bits wide, 2097 maybe we can deduce a value of 1 or 0 independent of the data. 2098 Or else truncate the constant now 2099 rather than extend the variable at run time. 2100 2101 This is only interesting if the constant is the wider arg. 2102 Also, it is not safe if the constant is unsigned and the 2103 variable arg is signed, since in this case the variable 2104 would be sign-extended and then regarded as unsigned. 2105 Our technique fails in this case because the lowest/highest 2106 possible unsigned results don't follow naturally from the 2107 lowest/highest possible values of the variable operand. 2108 For just EQ_EXPR and NE_EXPR there is another technique that 2109 could be used: see if the constant can be faithfully represented 2110 in the other operand's type, by truncating it and reextending it 2111 and see if that preserves the constant's value. */ 2112 2113 if (!real1 && !real2 2114 && TREE_CODE (primop1) == INTEGER_CST 2115 && TYPE_PRECISION (TREE_TYPE (primop0)) < TYPE_PRECISION (*restype_ptr)) 2116 { 2117 int min_gt, max_gt, min_lt, max_lt; 2118 tree maxval, minval; 2119 /* 1 if comparison is nominally unsigned. */ 2120 int unsignedp = TYPE_UNSIGNED (*restype_ptr); 2121 tree val; 2122 2123 type = c_common_signed_or_unsigned_type (unsignedp0, 2124 TREE_TYPE (primop0)); 2125 2126 maxval = TYPE_MAX_VALUE (type); 2127 minval = TYPE_MIN_VALUE (type); 2128 2129 if (unsignedp && !unsignedp0) 2130 *restype_ptr = c_common_signed_type (*restype_ptr); 2131 2132 if (TREE_TYPE (primop1) != *restype_ptr) 2133 { 2134 /* Convert primop1 to target type, but do not introduce 2135 additional overflow. We know primop1 is an int_cst. */ 2136 tree tmp = build_int_cst_wide (*restype_ptr, 2137 TREE_INT_CST_LOW (primop1), 2138 TREE_INT_CST_HIGH (primop1)); 2139 2140 primop1 = force_fit_type (tmp, 0, TREE_OVERFLOW (primop1), 2141 TREE_CONSTANT_OVERFLOW (primop1)); 2142 } 2143 if (type != *restype_ptr) 2144 { 2145 minval = convert (*restype_ptr, minval); 2146 maxval = convert (*restype_ptr, maxval); 2147 } 2148 2149 if (unsignedp && unsignedp0) 2150 { 2151 min_gt = INT_CST_LT_UNSIGNED (primop1, minval); 2152 max_gt = INT_CST_LT_UNSIGNED (primop1, maxval); 2153 min_lt = INT_CST_LT_UNSIGNED (minval, primop1); 2154 max_lt = INT_CST_LT_UNSIGNED (maxval, primop1); 2155 } 2156 else 2157 { 2158 min_gt = INT_CST_LT (primop1, minval); 2159 max_gt = INT_CST_LT (primop1, maxval); 2160 min_lt = INT_CST_LT (minval, primop1); 2161 max_lt = INT_CST_LT (maxval, primop1); 2162 } 2163 2164 val = 0; 2165 /* This used to be a switch, but Genix compiler can't handle that. */ 2166 if (code == NE_EXPR) 2167 { 2168 if (max_lt || min_gt) 2169 val = truthvalue_true_node; 2170 } 2171 else if (code == EQ_EXPR) 2172 { 2173 if (max_lt || min_gt) 2174 val = truthvalue_false_node; 2175 } 2176 else if (code == LT_EXPR) 2177 { 2178 if (max_lt) 2179 val = truthvalue_true_node; 2180 if (!min_lt) 2181 val = truthvalue_false_node; 2182 } 2183 else if (code == GT_EXPR) 2184 { 2185 if (min_gt) 2186 val = truthvalue_true_node; 2187 if (!max_gt) 2188 val = truthvalue_false_node; 2189 } 2190 else if (code == LE_EXPR) 2191 { 2192 if (!max_gt) 2193 val = truthvalue_true_node; 2194 if (min_gt) 2195 val = truthvalue_false_node; 2196 } 2197 else if (code == GE_EXPR) 2198 { 2199 if (!min_lt) 2200 val = truthvalue_true_node; 2201 if (max_lt) 2202 val = truthvalue_false_node; 2203 } 2204 2205 /* If primop0 was sign-extended and unsigned comparison specd, 2206 we did a signed comparison above using the signed type bounds. 2207 But the comparison we output must be unsigned. 2208 2209 Also, for inequalities, VAL is no good; but if the signed 2210 comparison had *any* fixed result, it follows that the 2211 unsigned comparison just tests the sign in reverse 2212 (positive values are LE, negative ones GE). 2213 So we can generate an unsigned comparison 2214 against an extreme value of the signed type. */ 2215 2216 if (unsignedp && !unsignedp0) 2217 { 2218 if (val != 0) 2219 switch (code) 2220 { 2221 case LT_EXPR: 2222 case GE_EXPR: 2223 primop1 = TYPE_MIN_VALUE (type); 2224 val = 0; 2225 break; 2226 2227 case LE_EXPR: 2228 case GT_EXPR: 2229 primop1 = TYPE_MAX_VALUE (type); 2230 val = 0; 2231 break; 2232 2233 default: 2234 break; 2235 } 2236 type = c_common_unsigned_type (type); 2237 } 2238 2239 if (TREE_CODE (primop0) != INTEGER_CST) 2240 { 2241 if (val == truthvalue_false_node) 2242 warning (0, "comparison is always false due to limited range of data type"); 2243 if (val == truthvalue_true_node) 2244 warning (0, "comparison is always true due to limited range of data type"); 2245 } 2246 2247 if (val != 0) 2248 { 2249 /* Don't forget to evaluate PRIMOP0 if it has side effects. */ 2250 if (TREE_SIDE_EFFECTS (primop0)) 2251 return build2 (COMPOUND_EXPR, TREE_TYPE (val), primop0, val); 2252 return val; 2253 } 2254 2255 /* Value is not predetermined, but do the comparison 2256 in the type of the operand that is not constant. 2257 TYPE is already properly set. */ 2258 } 2259 2260 /* If either arg is decimal float and the other is float, find the 2261 proper common type to use for comparison. */ 2262 else if (real1 && real2 2263 && (DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (primop0))) 2264 || DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (primop1))))) 2265 type = common_type (TREE_TYPE (primop0), TREE_TYPE (primop1)); 2266 2267 else if (real1 && real2 2268 && (TYPE_PRECISION (TREE_TYPE (primop0)) 2269 == TYPE_PRECISION (TREE_TYPE (primop1)))) 2270 type = TREE_TYPE (primop0); 2271 2272 /* If args' natural types are both narrower than nominal type 2273 and both extend in the same manner, compare them 2274 in the type of the wider arg. 2275 Otherwise must actually extend both to the nominal 2276 common type lest different ways of extending 2277 alter the result. 2278 (eg, (short)-1 == (unsigned short)-1 should be 0.) */ 2279 2280 else if (unsignedp0 == unsignedp1 && real1 == real2 2281 && TYPE_PRECISION (TREE_TYPE (primop0)) < TYPE_PRECISION (*restype_ptr) 2282 && TYPE_PRECISION (TREE_TYPE (primop1)) < TYPE_PRECISION (*restype_ptr)) 2283 { 2284 type = common_type (TREE_TYPE (primop0), TREE_TYPE (primop1)); 2285 type = c_common_signed_or_unsigned_type (unsignedp0 2286 || TYPE_UNSIGNED (*restype_ptr), 2287 type); 2288 /* Make sure shorter operand is extended the right way 2289 to match the longer operand. */ 2290 primop0 2291 = convert (c_common_signed_or_unsigned_type (unsignedp0, 2292 TREE_TYPE (primop0)), 2293 primop0); 2294 primop1 2295 = convert (c_common_signed_or_unsigned_type (unsignedp1, 2296 TREE_TYPE (primop1)), 2297 primop1); 2298 } 2299 else 2300 { 2301 /* Here we must do the comparison on the nominal type 2302 using the args exactly as we received them. */ 2303 type = *restype_ptr; 2304 primop0 = op0; 2305 primop1 = op1; 2306 2307 if (!real1 && !real2 && integer_zerop (primop1) 2308 && TYPE_UNSIGNED (*restype_ptr)) 2309 { 2310 tree value = 0; 2311 switch (code) 2312 { 2313 case GE_EXPR: 2314 /* All unsigned values are >= 0, so we warn if extra warnings 2315 are requested. However, if OP0 is a constant that is 2316 >= 0, the signedness of the comparison isn't an issue, 2317 so suppress the warning. */ 2318 if (extra_warnings && !in_system_header 2319 && !(TREE_CODE (primop0) == INTEGER_CST 2320 && !TREE_OVERFLOW (convert (c_common_signed_type (type), 2321 primop0)))) 2322 warning (0, "comparison of unsigned expression >= 0 is always true"); 2323 value = truthvalue_true_node; 2324 break; 2325 2326 case LT_EXPR: 2327 if (extra_warnings && !in_system_header 2328 && !(TREE_CODE (primop0) == INTEGER_CST 2329 && !TREE_OVERFLOW (convert (c_common_signed_type (type), 2330 primop0)))) 2331 warning (0, "comparison of unsigned expression < 0 is always false"); 2332 value = truthvalue_false_node; 2333 break; 2334 2335 default: 2336 break; 2337 } 2338 2339 if (value != 0) 2340 { 2341 /* Don't forget to evaluate PRIMOP0 if it has side effects. */ 2342 if (TREE_SIDE_EFFECTS (primop0)) 2343 return build2 (COMPOUND_EXPR, TREE_TYPE (value), 2344 primop0, value); 2345 return value; 2346 } 2347 } 2348 } 2349 2350 *op0_ptr = convert (type, primop0); 2351 *op1_ptr = convert (type, primop1); 2352 2353 *restype_ptr = truthvalue_type_node; 2354 2355 return 0; 2356} 2357 2358/* Return a tree for the sum or difference (RESULTCODE says which) 2359 of pointer PTROP and integer INTOP. */ 2360 2361tree 2362pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop) 2363{ 2364 tree size_exp, ret; 2365 2366 /* The result is a pointer of the same type that is being added. */ 2367 2368 tree result_type = TREE_TYPE (ptrop); 2369 2370 if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE) 2371 { 2372 if (pedantic || warn_pointer_arith) 2373 pedwarn ("pointer of type %<void *%> used in arithmetic"); 2374 size_exp = integer_one_node; 2375 } 2376 else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE) 2377 { 2378 if (pedantic || warn_pointer_arith) 2379 pedwarn ("pointer to a function used in arithmetic"); 2380 size_exp = integer_one_node; 2381 } 2382 else if (TREE_CODE (TREE_TYPE (result_type)) == METHOD_TYPE) 2383 { 2384 if (pedantic || warn_pointer_arith) 2385 pedwarn ("pointer to member function used in arithmetic"); 2386 size_exp = integer_one_node; 2387 } 2388 else 2389 size_exp = size_in_bytes (TREE_TYPE (result_type)); 2390 2391 /* We are manipulating pointer values, so we don't need to warn 2392 about relying on undefined signed overflow. We disable the 2393 warning here because we use integer types so fold won't know that 2394 they are really pointers. */ 2395 fold_defer_overflow_warnings (); 2396 2397 /* If what we are about to multiply by the size of the elements 2398 contains a constant term, apply distributive law 2399 and multiply that constant term separately. 2400 This helps produce common subexpressions. */ 2401 2402 if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR) 2403 && !TREE_CONSTANT (intop) 2404 && TREE_CONSTANT (TREE_OPERAND (intop, 1)) 2405 && TREE_CONSTANT (size_exp) 2406 /* If the constant comes from pointer subtraction, 2407 skip this optimization--it would cause an error. */ 2408 && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE 2409 /* If the constant is unsigned, and smaller than the pointer size, 2410 then we must skip this optimization. This is because it could cause 2411 an overflow error if the constant is negative but INTOP is not. */ 2412 && (!TYPE_UNSIGNED (TREE_TYPE (intop)) 2413 || (TYPE_PRECISION (TREE_TYPE (intop)) 2414 == TYPE_PRECISION (TREE_TYPE (ptrop))))) 2415 { 2416 enum tree_code subcode = resultcode; 2417 tree int_type = TREE_TYPE (intop); 2418 if (TREE_CODE (intop) == MINUS_EXPR) 2419 subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR); 2420 /* Convert both subexpression types to the type of intop, 2421 because weird cases involving pointer arithmetic 2422 can result in a sum or difference with different type args. */ 2423 ptrop = build_binary_op (subcode, ptrop, 2424 convert (int_type, TREE_OPERAND (intop, 1)), 1); 2425 intop = convert (int_type, TREE_OPERAND (intop, 0)); 2426 } 2427 2428 /* Convert the integer argument to a type the same size as sizetype 2429 so the multiply won't overflow spuriously. */ 2430 2431 if (TYPE_PRECISION (TREE_TYPE (intop)) != TYPE_PRECISION (sizetype) 2432 || TYPE_UNSIGNED (TREE_TYPE (intop)) != TYPE_UNSIGNED (sizetype)) 2433 intop = convert (c_common_type_for_size (TYPE_PRECISION (sizetype), 2434 TYPE_UNSIGNED (sizetype)), intop); 2435 2436 /* Replace the integer argument with a suitable product by the object size. 2437 Do this multiplication as signed, then convert to the appropriate 2438 pointer type (actually unsigned integral). */ 2439 2440 intop = convert (result_type, 2441 build_binary_op (MULT_EXPR, intop, 2442 convert (TREE_TYPE (intop), size_exp), 1)); 2443 2444 /* Create the sum or difference. */ 2445 ret = fold_build2 (resultcode, result_type, ptrop, intop); 2446 2447 fold_undefer_and_ignore_overflow_warnings (); 2448 2449 return ret; 2450} 2451 2452/* Prepare expr to be an argument of a TRUTH_NOT_EXPR, 2453 or for an `if' or `while' statement or ?..: exp. It should already 2454 have been validated to be of suitable type; otherwise, a bad 2455 diagnostic may result. 2456 2457 This preparation consists of taking the ordinary 2458 representation of an expression expr and producing a valid tree 2459 boolean expression describing whether expr is nonzero. We could 2460 simply always do build_binary_op (NE_EXPR, expr, truthvalue_false_node, 1), 2461 but we optimize comparisons, &&, ||, and !. 2462 2463 The resulting type should always be `truthvalue_type_node'. */ 2464 2465tree 2466c_common_truthvalue_conversion (tree expr) 2467{ 2468 switch (TREE_CODE (expr)) 2469 { 2470 case EQ_EXPR: case NE_EXPR: case UNEQ_EXPR: case LTGT_EXPR: 2471 case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR: 2472 case UNLE_EXPR: case UNGE_EXPR: case UNLT_EXPR: case UNGT_EXPR: 2473 case ORDERED_EXPR: case UNORDERED_EXPR: 2474 if (TREE_TYPE (expr) == truthvalue_type_node) 2475 return expr; 2476 return build2 (TREE_CODE (expr), truthvalue_type_node, 2477 TREE_OPERAND (expr, 0), TREE_OPERAND (expr, 1)); 2478 2479 case TRUTH_ANDIF_EXPR: 2480 case TRUTH_ORIF_EXPR: 2481 case TRUTH_AND_EXPR: 2482 case TRUTH_OR_EXPR: 2483 case TRUTH_XOR_EXPR: 2484 if (TREE_TYPE (expr) == truthvalue_type_node) 2485 return expr; 2486 return build2 (TREE_CODE (expr), truthvalue_type_node, 2487 c_common_truthvalue_conversion (TREE_OPERAND (expr, 0)), 2488 c_common_truthvalue_conversion (TREE_OPERAND (expr, 1))); 2489 2490 case TRUTH_NOT_EXPR: 2491 if (TREE_TYPE (expr) == truthvalue_type_node) 2492 return expr; 2493 return build1 (TREE_CODE (expr), truthvalue_type_node, 2494 c_common_truthvalue_conversion (TREE_OPERAND (expr, 0))); 2495 2496 case ERROR_MARK: 2497 return expr; 2498 2499 case INTEGER_CST: 2500 /* Avoid integer_zerop to ignore TREE_CONSTANT_OVERFLOW. */ 2501 return (TREE_INT_CST_LOW (expr) != 0 || TREE_INT_CST_HIGH (expr) != 0) 2502 ? truthvalue_true_node 2503 : truthvalue_false_node; 2504 2505 case REAL_CST: 2506 return real_compare (NE_EXPR, &TREE_REAL_CST (expr), &dconst0) 2507 ? truthvalue_true_node 2508 : truthvalue_false_node; 2509 2510 case FUNCTION_DECL: 2511 expr = build_unary_op (ADDR_EXPR, expr, 0); 2512 /* Fall through. */ 2513 2514 case ADDR_EXPR: 2515 { 2516 tree inner = TREE_OPERAND (expr, 0); 2517 if (DECL_P (inner) 2518 && (TREE_CODE (inner) == PARM_DECL 2519 || TREE_CODE (inner) == LABEL_DECL 2520 || !DECL_WEAK (inner))) 2521 { 2522 /* Common Ada/Pascal programmer's mistake. We always warn 2523 about this since it is so bad. */ 2524 warning (OPT_Waddress, 2525 "the address of %qD will always evaluate as %<true%>", 2526 inner); 2527 return truthvalue_true_node; 2528 } 2529 2530 /* If we are taking the address of an external decl, it might be 2531 zero if it is weak, so we cannot optimize. */ 2532 if (DECL_P (inner) 2533 && DECL_EXTERNAL (inner)) 2534 break; 2535 2536 if (TREE_SIDE_EFFECTS (inner)) 2537 return build2 (COMPOUND_EXPR, truthvalue_type_node, 2538 inner, truthvalue_true_node); 2539 else 2540 return truthvalue_true_node; 2541 } 2542 2543 case COMPLEX_EXPR: 2544 return build_binary_op ((TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)) 2545 ? TRUTH_OR_EXPR : TRUTH_ORIF_EXPR), 2546 c_common_truthvalue_conversion (TREE_OPERAND (expr, 0)), 2547 c_common_truthvalue_conversion (TREE_OPERAND (expr, 1)), 2548 0); 2549 2550 case NEGATE_EXPR: 2551 case ABS_EXPR: 2552 case FLOAT_EXPR: 2553 /* These don't change whether an object is nonzero or zero. */ 2554 return c_common_truthvalue_conversion (TREE_OPERAND (expr, 0)); 2555 2556 case LROTATE_EXPR: 2557 case RROTATE_EXPR: 2558 /* These don't change whether an object is zero or nonzero, but 2559 we can't ignore them if their second arg has side-effects. */ 2560 if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1))) 2561 return build2 (COMPOUND_EXPR, truthvalue_type_node, 2562 TREE_OPERAND (expr, 1), 2563 c_common_truthvalue_conversion (TREE_OPERAND (expr, 0))); 2564 else 2565 return c_common_truthvalue_conversion (TREE_OPERAND (expr, 0)); 2566 2567 case COND_EXPR: 2568 /* Distribute the conversion into the arms of a COND_EXPR. */ 2569 return fold_build3 (COND_EXPR, truthvalue_type_node, 2570 TREE_OPERAND (expr, 0), 2571 c_common_truthvalue_conversion (TREE_OPERAND (expr, 1)), 2572 c_common_truthvalue_conversion (TREE_OPERAND (expr, 2))); 2573 2574 case CONVERT_EXPR: 2575 case NOP_EXPR: 2576 /* Don't cancel the effect of a CONVERT_EXPR from a REFERENCE_TYPE, 2577 since that affects how `default_conversion' will behave. */ 2578 if (TREE_CODE (TREE_TYPE (expr)) == REFERENCE_TYPE 2579 || TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == REFERENCE_TYPE) 2580 break; 2581 /* If this is widening the argument, we can ignore it. */ 2582 if (TYPE_PRECISION (TREE_TYPE (expr)) 2583 >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (expr, 0)))) 2584 return c_common_truthvalue_conversion (TREE_OPERAND (expr, 0)); 2585 break; 2586 2587 case MODIFY_EXPR: 2588 if (!TREE_NO_WARNING (expr) 2589 && warn_parentheses) 2590 { 2591 warning (OPT_Wparentheses, 2592 "suggest parentheses around assignment used as truth value"); 2593 TREE_NO_WARNING (expr) = 1; 2594 } 2595 break; 2596 2597 default: 2598 break; 2599 } 2600 2601 if (TREE_CODE (TREE_TYPE (expr)) == COMPLEX_TYPE) 2602 { 2603 tree t = save_expr (expr); 2604 return (build_binary_op 2605 ((TREE_SIDE_EFFECTS (expr) 2606 ? TRUTH_OR_EXPR : TRUTH_ORIF_EXPR), 2607 c_common_truthvalue_conversion (build_unary_op (REALPART_EXPR, t, 0)), 2608 c_common_truthvalue_conversion (build_unary_op (IMAGPART_EXPR, t, 0)), 2609 0)); 2610 } 2611 2612 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1); 2613} 2614 2615static void def_builtin_1 (enum built_in_function fncode, 2616 const char *name, 2617 enum built_in_class fnclass, 2618 tree fntype, tree libtype, 2619 bool both_p, bool fallback_p, bool nonansi_p, 2620 tree fnattrs, bool implicit_p); 2621 2622/* Make a variant type in the proper way for C/C++, propagating qualifiers 2623 down to the element type of an array. */ 2624 2625tree 2626c_build_qualified_type (tree type, int type_quals) 2627{ 2628 if (type == error_mark_node) 2629 return type; 2630 2631 if (TREE_CODE (type) == ARRAY_TYPE) 2632 { 2633 tree t; 2634 tree element_type = c_build_qualified_type (TREE_TYPE (type), 2635 type_quals); 2636 2637 /* See if we already have an identically qualified type. */ 2638 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t)) 2639 { 2640 if (TYPE_QUALS (strip_array_types (t)) == type_quals 2641 && TYPE_NAME (t) == TYPE_NAME (type) 2642 && TYPE_CONTEXT (t) == TYPE_CONTEXT (type) 2643 && attribute_list_equal (TYPE_ATTRIBUTES (t), 2644 TYPE_ATTRIBUTES (type))) 2645 break; 2646 } 2647 if (!t) 2648 { 2649 t = build_variant_type_copy (type); 2650 TREE_TYPE (t) = element_type; 2651 } 2652 return t; 2653 } 2654 2655 /* A restrict-qualified pointer type must be a pointer to object or 2656 incomplete type. Note that the use of POINTER_TYPE_P also allows 2657 REFERENCE_TYPEs, which is appropriate for C++. */ 2658 if ((type_quals & TYPE_QUAL_RESTRICT) 2659 && (!POINTER_TYPE_P (type) 2660 || !C_TYPE_OBJECT_OR_INCOMPLETE_P (TREE_TYPE (type)))) 2661 { 2662 error ("invalid use of %<restrict%>"); 2663 type_quals &= ~TYPE_QUAL_RESTRICT; 2664 } 2665 2666 return build_qualified_type (type, type_quals); 2667} 2668 2669/* Apply the TYPE_QUALS to the new DECL. */ 2670 2671void 2672c_apply_type_quals_to_decl (int type_quals, tree decl) 2673{ 2674 tree type = TREE_TYPE (decl); 2675 2676 if (type == error_mark_node) 2677 return; 2678 2679 if (((type_quals & TYPE_QUAL_CONST) 2680 || (type && TREE_CODE (type) == REFERENCE_TYPE)) 2681 /* An object declared 'const' is only readonly after it is 2682 initialized. We don't have any way of expressing this currently, 2683 so we need to be conservative and unset TREE_READONLY for types 2684 with constructors. Otherwise aliasing code will ignore stores in 2685 an inline constructor. */ 2686 && !(type && TYPE_NEEDS_CONSTRUCTING (type))) 2687 TREE_READONLY (decl) = 1; 2688 if (type_quals & TYPE_QUAL_VOLATILE) 2689 { 2690 TREE_SIDE_EFFECTS (decl) = 1; 2691 TREE_THIS_VOLATILE (decl) = 1; 2692 } 2693 if (type_quals & TYPE_QUAL_RESTRICT) 2694 { 2695 while (type && TREE_CODE (type) == ARRAY_TYPE) 2696 /* Allow 'restrict' on arrays of pointers. 2697 FIXME currently we just ignore it. */ 2698 type = TREE_TYPE (type); 2699 if (!type 2700 || !POINTER_TYPE_P (type) 2701 || !C_TYPE_OBJECT_OR_INCOMPLETE_P (TREE_TYPE (type))) 2702 error ("invalid use of %<restrict%>"); 2703 else if (flag_strict_aliasing && type == TREE_TYPE (decl)) 2704 /* Indicate we need to make a unique alias set for this pointer. 2705 We can't do it here because it might be pointing to an 2706 incomplete type. */ 2707 DECL_POINTER_ALIAS_SET (decl) = -2; 2708 } 2709} 2710 2711/* Hash function for the problem of multiple type definitions in 2712 different files. This must hash all types that will compare 2713 equal via comptypes to the same value. In practice it hashes 2714 on some of the simple stuff and leaves the details to comptypes. */ 2715 2716static hashval_t 2717c_type_hash (const void *p) 2718{ 2719 int i = 0; 2720 int shift, size; 2721 tree t = (tree) p; 2722 tree t2; 2723 switch (TREE_CODE (t)) 2724 { 2725 /* For pointers, hash on pointee type plus some swizzling. */ 2726 case POINTER_TYPE: 2727 return c_type_hash (TREE_TYPE (t)) ^ 0x3003003; 2728 /* Hash on number of elements and total size. */ 2729 case ENUMERAL_TYPE: 2730 shift = 3; 2731 t2 = TYPE_VALUES (t); 2732 break; 2733 case RECORD_TYPE: 2734 shift = 0; 2735 t2 = TYPE_FIELDS (t); 2736 break; 2737 case QUAL_UNION_TYPE: 2738 shift = 1; 2739 t2 = TYPE_FIELDS (t); 2740 break; 2741 case UNION_TYPE: 2742 shift = 2; 2743 t2 = TYPE_FIELDS (t); 2744 break; 2745 default: 2746 gcc_unreachable (); 2747 } 2748 for (; t2; t2 = TREE_CHAIN (t2)) 2749 i++; 2750 size = TREE_INT_CST_LOW (TYPE_SIZE (t)); 2751 return ((size << 24) | (i << shift)); 2752} 2753 2754static GTY((param_is (union tree_node))) htab_t type_hash_table; 2755 2756/* Return the typed-based alias set for T, which may be an expression 2757 or a type. Return -1 if we don't do anything special. */ 2758 2759HOST_WIDE_INT 2760c_common_get_alias_set (tree t) 2761{ 2762 tree u; 2763 PTR *slot; 2764 2765 /* Permit type-punning when accessing a union, provided the access 2766 is directly through the union. For example, this code does not 2767 permit taking the address of a union member and then storing 2768 through it. Even the type-punning allowed here is a GCC 2769 extension, albeit a common and useful one; the C standard says 2770 that such accesses have implementation-defined behavior. */ 2771 for (u = t; 2772 TREE_CODE (u) == COMPONENT_REF || TREE_CODE (u) == ARRAY_REF; 2773 u = TREE_OPERAND (u, 0)) 2774 if (TREE_CODE (u) == COMPONENT_REF 2775 && TREE_CODE (TREE_TYPE (TREE_OPERAND (u, 0))) == UNION_TYPE) 2776 return 0; 2777 2778 /* That's all the expressions we handle specially. */ 2779 if (!TYPE_P (t)) 2780 return -1; 2781 2782 /* The C standard guarantees that any object may be accessed via an 2783 lvalue that has character type. */ 2784 if (t == char_type_node 2785 || t == signed_char_type_node 2786 || t == unsigned_char_type_node) 2787 return 0; 2788 2789 /* If it has the may_alias attribute, it can alias anything. */ 2790 if (lookup_attribute ("may_alias", TYPE_ATTRIBUTES (t))) 2791 return 0; 2792 2793 /* The C standard specifically allows aliasing between signed and 2794 unsigned variants of the same type. We treat the signed 2795 variant as canonical. */ 2796 if (TREE_CODE (t) == INTEGER_TYPE && TYPE_UNSIGNED (t)) 2797 { 2798 tree t1 = c_common_signed_type (t); 2799 2800 /* t1 == t can happen for boolean nodes which are always unsigned. */ 2801 if (t1 != t) 2802 return get_alias_set (t1); 2803 } 2804 else if (POINTER_TYPE_P (t)) 2805 { 2806 tree t1; 2807 2808 /* Unfortunately, there is no canonical form of a pointer type. 2809 In particular, if we have `typedef int I', then `int *', and 2810 `I *' are different types. So, we have to pick a canonical 2811 representative. We do this below. 2812 2813 Technically, this approach is actually more conservative that 2814 it needs to be. In particular, `const int *' and `int *' 2815 should be in different alias sets, according to the C and C++ 2816 standard, since their types are not the same, and so, 2817 technically, an `int **' and `const int **' cannot point at 2818 the same thing. 2819 2820 But, the standard is wrong. In particular, this code is 2821 legal C++: 2822 2823 int *ip; 2824 int **ipp = &ip; 2825 const int* const* cipp = ipp; 2826 2827 And, it doesn't make sense for that to be legal unless you 2828 can dereference IPP and CIPP. So, we ignore cv-qualifiers on 2829 the pointed-to types. This issue has been reported to the 2830 C++ committee. */ 2831 t1 = build_type_no_quals (t); 2832 if (t1 != t) 2833 return get_alias_set (t1); 2834 } 2835 2836 /* Handle the case of multiple type nodes referring to "the same" type, 2837 which occurs with IMA. These share an alias set. FIXME: Currently only 2838 C90 is handled. (In C99 type compatibility is not transitive, which 2839 complicates things mightily. The alias set splay trees can theoretically 2840 represent this, but insertion is tricky when you consider all the 2841 different orders things might arrive in.) */ 2842 2843 if (c_language != clk_c || flag_isoc99) 2844 return -1; 2845 2846 /* Save time if there's only one input file. */ 2847 if (num_in_fnames == 1) 2848 return -1; 2849 2850 /* Pointers need special handling if they point to any type that 2851 needs special handling (below). */ 2852 if (TREE_CODE (t) == POINTER_TYPE) 2853 { 2854 tree t2; 2855 /* Find bottom type under any nested POINTERs. */ 2856 for (t2 = TREE_TYPE (t); 2857 TREE_CODE (t2) == POINTER_TYPE; 2858 t2 = TREE_TYPE (t2)) 2859 ; 2860 if (TREE_CODE (t2) != RECORD_TYPE 2861 && TREE_CODE (t2) != ENUMERAL_TYPE 2862 && TREE_CODE (t2) != QUAL_UNION_TYPE 2863 && TREE_CODE (t2) != UNION_TYPE) 2864 return -1; 2865 if (TYPE_SIZE (t2) == 0) 2866 return -1; 2867 } 2868 /* These are the only cases that need special handling. */ 2869 if (TREE_CODE (t) != RECORD_TYPE 2870 && TREE_CODE (t) != ENUMERAL_TYPE 2871 && TREE_CODE (t) != QUAL_UNION_TYPE 2872 && TREE_CODE (t) != UNION_TYPE 2873 && TREE_CODE (t) != POINTER_TYPE) 2874 return -1; 2875 /* Undefined? */ 2876 if (TYPE_SIZE (t) == 0) 2877 return -1; 2878 2879 /* Look up t in hash table. Only one of the compatible types within each 2880 alias set is recorded in the table. */ 2881 if (!type_hash_table) 2882 type_hash_table = htab_create_ggc (1021, c_type_hash, 2883 (htab_eq) lang_hooks.types_compatible_p, 2884 NULL); 2885 slot = htab_find_slot (type_hash_table, t, INSERT); 2886 if (*slot != NULL) 2887 { 2888 TYPE_ALIAS_SET (t) = TYPE_ALIAS_SET ((tree)*slot); 2889 return TYPE_ALIAS_SET ((tree)*slot); 2890 } 2891 else 2892 /* Our caller will assign and record (in t) a new alias set; all we need 2893 to do is remember t in the hash table. */ 2894 *slot = t; 2895 2896 return -1; 2897} 2898 2899/* Compute the value of 'sizeof (TYPE)' or '__alignof__ (TYPE)', where the 2900 second parameter indicates which OPERATOR is being applied. The COMPLAIN 2901 flag controls whether we should diagnose possibly ill-formed 2902 constructs or not. */ 2903 2904tree 2905c_sizeof_or_alignof_type (tree type, bool is_sizeof, int complain) 2906{ 2907 const char *op_name; 2908 tree value = NULL; 2909 enum tree_code type_code = TREE_CODE (type); 2910 2911 op_name = is_sizeof ? "sizeof" : "__alignof__"; 2912 2913 if (type_code == FUNCTION_TYPE) 2914 { 2915 if (is_sizeof) 2916 { 2917 if (complain && (pedantic || warn_pointer_arith)) 2918 pedwarn ("invalid application of %<sizeof%> to a function type"); 2919 value = size_one_node; 2920 } 2921 else 2922 value = size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT); 2923 } 2924 else if (type_code == VOID_TYPE || type_code == ERROR_MARK) 2925 { 2926 if (type_code == VOID_TYPE 2927 && complain && (pedantic || warn_pointer_arith)) 2928 pedwarn ("invalid application of %qs to a void type", op_name); 2929 value = size_one_node; 2930 } 2931 else if (!COMPLETE_TYPE_P (type)) 2932 { 2933 if (complain) 2934 error ("invalid application of %qs to incomplete type %qT ", 2935 op_name, type); 2936 value = size_zero_node; 2937 } 2938 else 2939 { 2940 if (is_sizeof) 2941 /* Convert in case a char is more than one unit. */ 2942 value = size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type), 2943 size_int (TYPE_PRECISION (char_type_node) 2944 / BITS_PER_UNIT)); 2945 else 2946 value = size_int (TYPE_ALIGN_UNIT (type)); 2947 } 2948 2949 /* VALUE will have an integer type with TYPE_IS_SIZETYPE set. 2950 TYPE_IS_SIZETYPE means that certain things (like overflow) will 2951 never happen. However, this node should really have type 2952 `size_t', which is just a typedef for an ordinary integer type. */ 2953 value = fold_convert (size_type_node, value); 2954 gcc_assert (!TYPE_IS_SIZETYPE (TREE_TYPE (value))); 2955 2956 return value; 2957} 2958 2959/* Implement the __alignof keyword: Return the minimum required 2960 alignment of EXPR, measured in bytes. For VAR_DECL's and 2961 FIELD_DECL's return DECL_ALIGN (which can be set from an 2962 "aligned" __attribute__ specification). */ 2963 2964tree 2965c_alignof_expr (tree expr) 2966{ 2967 tree t; 2968 2969 if (TREE_CODE (expr) == VAR_DECL) 2970 t = size_int (DECL_ALIGN_UNIT (expr)); 2971 2972 else if (TREE_CODE (expr) == COMPONENT_REF 2973 && DECL_C_BIT_FIELD (TREE_OPERAND (expr, 1))) 2974 { 2975 error ("%<__alignof%> applied to a bit-field"); 2976 t = size_one_node; 2977 } 2978 else if (TREE_CODE (expr) == COMPONENT_REF 2979 && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL) 2980 t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (expr, 1))); 2981 2982 else if (TREE_CODE (expr) == INDIRECT_REF) 2983 { 2984 tree t = TREE_OPERAND (expr, 0); 2985 tree best = t; 2986 int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t))); 2987 2988 while ((TREE_CODE (t) == NOP_EXPR || TREE_CODE (t) == CONVERT_EXPR) 2989 && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE) 2990 { 2991 int thisalign; 2992 2993 t = TREE_OPERAND (t, 0); 2994 thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t))); 2995 if (thisalign > bestalign) 2996 best = t, bestalign = thisalign; 2997 } 2998 return c_alignof (TREE_TYPE (TREE_TYPE (best))); 2999 } 3000 else 3001 return c_alignof (TREE_TYPE (expr)); 3002 3003 return fold_convert (size_type_node, t); 3004} 3005 3006/* Handle C and C++ default attributes. */ 3007 3008enum built_in_attribute 3009{ 3010#define DEF_ATTR_NULL_TREE(ENUM) ENUM, 3011#define DEF_ATTR_INT(ENUM, VALUE) ENUM, 3012#define DEF_ATTR_IDENT(ENUM, STRING) ENUM, 3013#define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) ENUM, 3014#include "builtin-attrs.def" 3015#undef DEF_ATTR_NULL_TREE 3016#undef DEF_ATTR_INT 3017#undef DEF_ATTR_IDENT 3018#undef DEF_ATTR_TREE_LIST 3019 ATTR_LAST 3020}; 3021 3022static GTY(()) tree built_in_attributes[(int) ATTR_LAST]; 3023 3024static void c_init_attributes (void); 3025 3026enum c_builtin_type 3027{ 3028#define DEF_PRIMITIVE_TYPE(NAME, VALUE) NAME, 3029#define DEF_FUNCTION_TYPE_0(NAME, RETURN) NAME, 3030#define DEF_FUNCTION_TYPE_1(NAME, RETURN, ARG1) NAME, 3031#define DEF_FUNCTION_TYPE_2(NAME, RETURN, ARG1, ARG2) NAME, 3032#define DEF_FUNCTION_TYPE_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME, 3033#define DEF_FUNCTION_TYPE_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME, 3034#define DEF_FUNCTION_TYPE_5(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) NAME, 3035#define DEF_FUNCTION_TYPE_6(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6) NAME, 3036#define DEF_FUNCTION_TYPE_7(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6, ARG7) NAME, 3037#define DEF_FUNCTION_TYPE_VAR_0(NAME, RETURN) NAME, 3038#define DEF_FUNCTION_TYPE_VAR_1(NAME, RETURN, ARG1) NAME, 3039#define DEF_FUNCTION_TYPE_VAR_2(NAME, RETURN, ARG1, ARG2) NAME, 3040#define DEF_FUNCTION_TYPE_VAR_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME, 3041#define DEF_FUNCTION_TYPE_VAR_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME, 3042#define DEF_FUNCTION_TYPE_VAR_5(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG6) \ 3043 NAME, 3044#define DEF_POINTER_TYPE(NAME, TYPE) NAME, 3045#include "builtin-types.def" 3046#undef DEF_PRIMITIVE_TYPE 3047#undef DEF_FUNCTION_TYPE_0 3048#undef DEF_FUNCTION_TYPE_1 3049#undef DEF_FUNCTION_TYPE_2 3050#undef DEF_FUNCTION_TYPE_3 3051#undef DEF_FUNCTION_TYPE_4 3052#undef DEF_FUNCTION_TYPE_5 3053#undef DEF_FUNCTION_TYPE_6 3054#undef DEF_FUNCTION_TYPE_7 3055#undef DEF_FUNCTION_TYPE_VAR_0 3056#undef DEF_FUNCTION_TYPE_VAR_1 3057#undef DEF_FUNCTION_TYPE_VAR_2 3058#undef DEF_FUNCTION_TYPE_VAR_3 3059#undef DEF_FUNCTION_TYPE_VAR_4 3060#undef DEF_FUNCTION_TYPE_VAR_5 3061#undef DEF_POINTER_TYPE 3062 BT_LAST 3063}; 3064 3065typedef enum c_builtin_type builtin_type; 3066 3067/* A temporary array for c_common_nodes_and_builtins. Used in 3068 communication with def_fn_type. */ 3069static tree builtin_types[(int) BT_LAST + 1]; 3070 3071/* A helper function for c_common_nodes_and_builtins. Build function type 3072 for DEF with return type RET and N arguments. If VAR is true, then the 3073 function should be variadic after those N arguments. 3074 3075 Takes special care not to ICE if any of the types involved are 3076 error_mark_node, which indicates that said type is not in fact available 3077 (see builtin_type_for_size). In which case the function type as a whole 3078 should be error_mark_node. */ 3079 3080static void 3081def_fn_type (builtin_type def, builtin_type ret, bool var, int n, ...) 3082{ 3083 tree args = NULL, t; 3084 va_list list; 3085 int i; 3086 3087 va_start (list, n); 3088 for (i = 0; i < n; ++i) 3089 { 3090 builtin_type a = va_arg (list, builtin_type); 3091 t = builtin_types[a]; 3092 if (t == error_mark_node) 3093 goto egress; 3094 args = tree_cons (NULL_TREE, t, args); 3095 } 3096 va_end (list); 3097 3098 args = nreverse (args); 3099 if (!var) 3100 args = chainon (args, void_list_node); 3101 3102 t = builtin_types[ret]; 3103 if (t == error_mark_node) 3104 goto egress; 3105 t = build_function_type (t, args); 3106 3107 egress: 3108 builtin_types[def] = t; 3109} 3110 3111/* Build tree nodes and builtin functions common to both C and C++ language 3112 frontends. */ 3113 3114void 3115c_common_nodes_and_builtins (void) 3116{ 3117 int wchar_type_size; 3118 tree array_domain_type; 3119 tree va_list_ref_type_node; 3120 tree va_list_arg_type_node; 3121 3122 /* Define `int' and `char' first so that dbx will output them first. */ 3123 record_builtin_type (RID_INT, NULL, integer_type_node); 3124 record_builtin_type (RID_CHAR, "char", char_type_node); 3125 3126 /* `signed' is the same as `int'. FIXME: the declarations of "signed", 3127 "unsigned long", "long long unsigned" and "unsigned short" were in C++ 3128 but not C. Are the conditionals here needed? */ 3129 if (c_dialect_cxx ()) 3130 record_builtin_type (RID_SIGNED, NULL, integer_type_node); 3131 record_builtin_type (RID_LONG, "long int", long_integer_type_node); 3132 record_builtin_type (RID_UNSIGNED, "unsigned int", unsigned_type_node); 3133 record_builtin_type (RID_MAX, "long unsigned int", 3134 long_unsigned_type_node); 3135 if (c_dialect_cxx ()) 3136 record_builtin_type (RID_MAX, "unsigned long", long_unsigned_type_node); 3137 record_builtin_type (RID_MAX, "long long int", 3138 long_long_integer_type_node); 3139 record_builtin_type (RID_MAX, "long long unsigned int", 3140 long_long_unsigned_type_node); 3141 if (c_dialect_cxx ()) 3142 record_builtin_type (RID_MAX, "long long unsigned", 3143 long_long_unsigned_type_node); 3144 record_builtin_type (RID_SHORT, "short int", short_integer_type_node); 3145 record_builtin_type (RID_MAX, "short unsigned int", 3146 short_unsigned_type_node); 3147 if (c_dialect_cxx ()) 3148 record_builtin_type (RID_MAX, "unsigned short", 3149 short_unsigned_type_node); 3150 3151 /* Define both `signed char' and `unsigned char'. */ 3152 record_builtin_type (RID_MAX, "signed char", signed_char_type_node); 3153 record_builtin_type (RID_MAX, "unsigned char", unsigned_char_type_node); 3154 3155 /* These are types that c_common_type_for_size and 3156 c_common_type_for_mode use. */ 3157 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE, 3158 intQI_type_node)); 3159 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE, 3160 intHI_type_node)); 3161 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE, 3162 intSI_type_node)); 3163 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE, 3164 intDI_type_node)); 3165#if HOST_BITS_PER_WIDE_INT >= 64 3166 if (targetm.scalar_mode_supported_p (TImode)) 3167 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, 3168 get_identifier ("__int128_t"), 3169 intTI_type_node)); 3170#endif 3171 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE, 3172 unsigned_intQI_type_node)); 3173 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE, 3174 unsigned_intHI_type_node)); 3175 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE, 3176 unsigned_intSI_type_node)); 3177 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE, 3178 unsigned_intDI_type_node)); 3179#if HOST_BITS_PER_WIDE_INT >= 64 3180 if (targetm.scalar_mode_supported_p (TImode)) 3181 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, 3182 get_identifier ("__uint128_t"), 3183 unsigned_intTI_type_node)); 3184#endif 3185 3186 /* Create the widest literal types. */ 3187 widest_integer_literal_type_node 3188 = make_signed_type (HOST_BITS_PER_WIDE_INT * 2); 3189 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE, 3190 widest_integer_literal_type_node)); 3191 3192 widest_unsigned_literal_type_node 3193 = make_unsigned_type (HOST_BITS_PER_WIDE_INT * 2); 3194 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE, 3195 widest_unsigned_literal_type_node)); 3196 3197 /* `unsigned long' is the standard type for sizeof. 3198 Note that stddef.h uses `unsigned long', 3199 and this must agree, even if long and int are the same size. */ 3200 size_type_node = 3201 TREE_TYPE (identifier_global_value (get_identifier (SIZE_TYPE))); 3202 signed_size_type_node = c_common_signed_type (size_type_node); 3203 set_sizetype (size_type_node); 3204 3205 pid_type_node = 3206 TREE_TYPE (identifier_global_value (get_identifier (PID_TYPE))); 3207 3208 build_common_tree_nodes_2 (flag_short_double); 3209 3210 record_builtin_type (RID_FLOAT, NULL, float_type_node); 3211 record_builtin_type (RID_DOUBLE, NULL, double_type_node); 3212 record_builtin_type (RID_MAX, "long double", long_double_type_node); 3213 3214 /* Only supported decimal floating point extension if the target 3215 actually supports underlying modes. */ 3216 if (targetm.scalar_mode_supported_p (SDmode) 3217 && targetm.scalar_mode_supported_p (DDmode) 3218 && targetm.scalar_mode_supported_p (TDmode)) 3219 { 3220 record_builtin_type (RID_DFLOAT32, NULL, dfloat32_type_node); 3221 record_builtin_type (RID_DFLOAT64, NULL, dfloat64_type_node); 3222 record_builtin_type (RID_DFLOAT128, NULL, dfloat128_type_node); 3223 } 3224 3225 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, 3226 get_identifier ("complex int"), 3227 complex_integer_type_node)); 3228 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, 3229 get_identifier ("complex float"), 3230 complex_float_type_node)); 3231 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, 3232 get_identifier ("complex double"), 3233 complex_double_type_node)); 3234 lang_hooks.decls.pushdecl 3235 (build_decl (TYPE_DECL, get_identifier ("complex long double"), 3236 complex_long_double_type_node)); 3237 3238 if (c_dialect_cxx ()) 3239 /* For C++, make fileptr_type_node a distinct void * type until 3240 FILE type is defined. */ 3241 fileptr_type_node = build_variant_type_copy (ptr_type_node); 3242 3243 record_builtin_type (RID_VOID, NULL, void_type_node); 3244 3245 /* This node must not be shared. */ 3246 void_zero_node = make_node (INTEGER_CST); 3247 TREE_TYPE (void_zero_node) = void_type_node; 3248 3249 void_list_node = build_void_list_node (); 3250 3251 /* Make a type to be the domain of a few array types 3252 whose domains don't really matter. 3253 200 is small enough that it always fits in size_t 3254 and large enough that it can hold most function names for the 3255 initializations of __FUNCTION__ and __PRETTY_FUNCTION__. */ 3256 array_domain_type = build_index_type (size_int (200)); 3257 3258 /* Make a type for arrays of characters. 3259 With luck nothing will ever really depend on the length of this 3260 array type. */ 3261 char_array_type_node 3262 = build_array_type (char_type_node, array_domain_type); 3263 3264 /* Likewise for arrays of ints. */ 3265 int_array_type_node 3266 = build_array_type (integer_type_node, array_domain_type); 3267 3268 string_type_node = build_pointer_type (char_type_node); 3269 const_string_type_node 3270 = build_pointer_type (build_qualified_type 3271 (char_type_node, TYPE_QUAL_CONST)); 3272 3273 /* This is special for C++ so functions can be overloaded. */ 3274 wchar_type_node = get_identifier (MODIFIED_WCHAR_TYPE); 3275 wchar_type_node = TREE_TYPE (identifier_global_value (wchar_type_node)); 3276 wchar_type_size = TYPE_PRECISION (wchar_type_node); 3277 if (c_dialect_cxx ()) 3278 { 3279 if (TYPE_UNSIGNED (wchar_type_node)) 3280 wchar_type_node = make_unsigned_type (wchar_type_size); 3281 else 3282 wchar_type_node = make_signed_type (wchar_type_size); 3283 record_builtin_type (RID_WCHAR, "wchar_t", wchar_type_node); 3284 } 3285 else 3286 { 3287 signed_wchar_type_node = c_common_signed_type (wchar_type_node); 3288 unsigned_wchar_type_node = c_common_unsigned_type (wchar_type_node); 3289 } 3290 3291 /* This is for wide string constants. */ 3292 wchar_array_type_node 3293 = build_array_type (wchar_type_node, array_domain_type); 3294 3295 wint_type_node = 3296 TREE_TYPE (identifier_global_value (get_identifier (WINT_TYPE))); 3297 3298 intmax_type_node = 3299 TREE_TYPE (identifier_global_value (get_identifier (INTMAX_TYPE))); 3300 uintmax_type_node = 3301 TREE_TYPE (identifier_global_value (get_identifier (UINTMAX_TYPE))); 3302 3303 default_function_type = build_function_type (integer_type_node, NULL_TREE); 3304 ptrdiff_type_node 3305 = TREE_TYPE (identifier_global_value (get_identifier (PTRDIFF_TYPE))); 3306 unsigned_ptrdiff_type_node = c_common_unsigned_type (ptrdiff_type_node); 3307 3308 lang_hooks.decls.pushdecl 3309 (build_decl (TYPE_DECL, get_identifier ("__builtin_va_list"), 3310 va_list_type_node)); 3311 3312 if (TREE_CODE (va_list_type_node) == ARRAY_TYPE) 3313 { 3314 va_list_arg_type_node = va_list_ref_type_node = 3315 build_pointer_type (TREE_TYPE (va_list_type_node)); 3316 } 3317 else 3318 { 3319 va_list_arg_type_node = va_list_type_node; 3320 va_list_ref_type_node = build_reference_type (va_list_type_node); 3321 } 3322 3323#define DEF_PRIMITIVE_TYPE(ENUM, VALUE) \ 3324 builtin_types[ENUM] = VALUE; 3325#define DEF_FUNCTION_TYPE_0(ENUM, RETURN) \ 3326 def_fn_type (ENUM, RETURN, 0, 0); 3327#define DEF_FUNCTION_TYPE_1(ENUM, RETURN, ARG1) \ 3328 def_fn_type (ENUM, RETURN, 0, 1, ARG1); 3329#define DEF_FUNCTION_TYPE_2(ENUM, RETURN, ARG1, ARG2) \ 3330 def_fn_type (ENUM, RETURN, 0, 2, ARG1, ARG2); 3331#define DEF_FUNCTION_TYPE_3(ENUM, RETURN, ARG1, ARG2, ARG3) \ 3332 def_fn_type (ENUM, RETURN, 0, 3, ARG1, ARG2, ARG3); 3333#define DEF_FUNCTION_TYPE_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4) \ 3334 def_fn_type (ENUM, RETURN, 0, 4, ARG1, ARG2, ARG3, ARG4); 3335#define DEF_FUNCTION_TYPE_5(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) \ 3336 def_fn_type (ENUM, RETURN, 0, 5, ARG1, ARG2, ARG3, ARG4, ARG5); 3337#define DEF_FUNCTION_TYPE_6(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \ 3338 ARG6) \ 3339 def_fn_type (ENUM, RETURN, 0, 6, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6); 3340#define DEF_FUNCTION_TYPE_7(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \ 3341 ARG6, ARG7) \ 3342 def_fn_type (ENUM, RETURN, 0, 7, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6, ARG7); 3343#define DEF_FUNCTION_TYPE_VAR_0(ENUM, RETURN) \ 3344 def_fn_type (ENUM, RETURN, 1, 0); 3345#define DEF_FUNCTION_TYPE_VAR_1(ENUM, RETURN, ARG1) \ 3346 def_fn_type (ENUM, RETURN, 1, 1, ARG1); 3347#define DEF_FUNCTION_TYPE_VAR_2(ENUM, RETURN, ARG1, ARG2) \ 3348 def_fn_type (ENUM, RETURN, 1, 2, ARG1, ARG2); 3349#define DEF_FUNCTION_TYPE_VAR_3(ENUM, RETURN, ARG1, ARG2, ARG3) \ 3350 def_fn_type (ENUM, RETURN, 1, 3, ARG1, ARG2, ARG3); 3351#define DEF_FUNCTION_TYPE_VAR_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4) \ 3352 def_fn_type (ENUM, RETURN, 1, 4, ARG1, ARG2, ARG3, ARG4); 3353#define DEF_FUNCTION_TYPE_VAR_5(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) \ 3354 def_fn_type (ENUM, RETURN, 1, 5, ARG1, ARG2, ARG3, ARG4, ARG5); 3355#define DEF_POINTER_TYPE(ENUM, TYPE) \ 3356 builtin_types[(int) ENUM] = build_pointer_type (builtin_types[(int) TYPE]); 3357 3358#include "builtin-types.def" 3359 3360#undef DEF_PRIMITIVE_TYPE 3361#undef DEF_FUNCTION_TYPE_1 3362#undef DEF_FUNCTION_TYPE_2 3363#undef DEF_FUNCTION_TYPE_3 3364#undef DEF_FUNCTION_TYPE_4 3365#undef DEF_FUNCTION_TYPE_5 3366#undef DEF_FUNCTION_TYPE_6 3367#undef DEF_FUNCTION_TYPE_VAR_0 3368#undef DEF_FUNCTION_TYPE_VAR_1 3369#undef DEF_FUNCTION_TYPE_VAR_2 3370#undef DEF_FUNCTION_TYPE_VAR_3 3371#undef DEF_FUNCTION_TYPE_VAR_4 3372#undef DEF_FUNCTION_TYPE_VAR_5 3373#undef DEF_POINTER_TYPE 3374 builtin_types[(int) BT_LAST] = NULL_TREE; 3375 3376 c_init_attributes (); 3377 3378#define DEF_BUILTIN(ENUM, NAME, CLASS, TYPE, LIBTYPE, BOTH_P, FALLBACK_P, \ 3379 NONANSI_P, ATTRS, IMPLICIT, COND) \ 3380 if (NAME && COND) \ 3381 def_builtin_1 (ENUM, NAME, CLASS, \ 3382 builtin_types[(int) TYPE], \ 3383 builtin_types[(int) LIBTYPE], \ 3384 BOTH_P, FALLBACK_P, NONANSI_P, \ 3385 built_in_attributes[(int) ATTRS], IMPLICIT); 3386#include "builtins.def" 3387#undef DEF_BUILTIN 3388 3389 build_common_builtin_nodes (); 3390 3391 targetm.init_builtins (); 3392 if (flag_mudflap) 3393 mudflap_init (); 3394 3395 main_identifier_node = get_identifier ("main"); 3396 3397 /* Create the built-in __null node. It is important that this is 3398 not shared. */ 3399 null_node = make_node (INTEGER_CST); 3400 TREE_TYPE (null_node) = c_common_type_for_size (POINTER_SIZE, 0); 3401 3402 /* Since builtin_types isn't gc'ed, don't export these nodes. */ 3403 memset (builtin_types, 0, sizeof (builtin_types)); 3404} 3405 3406/* Look up the function in built_in_decls that corresponds to DECL 3407 and set ASMSPEC as its user assembler name. DECL must be a 3408 function decl that declares a builtin. */ 3409 3410void 3411set_builtin_user_assembler_name (tree decl, const char *asmspec) 3412{ 3413 tree builtin; 3414 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL 3415 && DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL 3416 && asmspec != 0); 3417 3418 builtin = built_in_decls [DECL_FUNCTION_CODE (decl)]; 3419 set_user_assembler_name (builtin, asmspec); 3420 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_MEMCPY) 3421 init_block_move_fn (asmspec); 3422 else if (DECL_FUNCTION_CODE (decl) == BUILT_IN_MEMSET) 3423 init_block_clear_fn (asmspec); 3424} 3425 3426/* The number of named compound-literals generated thus far. */ 3427static GTY(()) int compound_literal_number; 3428 3429/* Set DECL_NAME for DECL, a VAR_DECL for a compound-literal. */ 3430 3431void 3432set_compound_literal_name (tree decl) 3433{ 3434 char *name; 3435 ASM_FORMAT_PRIVATE_NAME (name, "__compound_literal", 3436 compound_literal_number); 3437 compound_literal_number++; 3438 DECL_NAME (decl) = get_identifier (name); 3439} 3440 3441tree 3442build_va_arg (tree expr, tree type) 3443{ 3444 return build1 (VA_ARG_EXPR, type, expr); 3445} 3446 3447 3448/* Linked list of disabled built-in functions. */ 3449 3450typedef struct disabled_builtin 3451{ 3452 const char *name; 3453 struct disabled_builtin *next; 3454} disabled_builtin; 3455static disabled_builtin *disabled_builtins = NULL; 3456 3457static bool builtin_function_disabled_p (const char *); 3458 3459/* Disable a built-in function specified by -fno-builtin-NAME. If NAME 3460 begins with "__builtin_", give an error. */ 3461 3462void 3463disable_builtin_function (const char *name) 3464{ 3465 if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0) 3466 error ("cannot disable built-in function %qs", name); 3467 else 3468 { 3469 disabled_builtin *new_disabled_builtin = XNEW (disabled_builtin); 3470 new_disabled_builtin->name = name; 3471 new_disabled_builtin->next = disabled_builtins; 3472 disabled_builtins = new_disabled_builtin; 3473 } 3474} 3475 3476 3477/* Return true if the built-in function NAME has been disabled, false 3478 otherwise. */ 3479 3480static bool 3481builtin_function_disabled_p (const char *name) 3482{ 3483 disabled_builtin *p; 3484 for (p = disabled_builtins; p != NULL; p = p->next) 3485 { 3486 if (strcmp (name, p->name) == 0) 3487 return true; 3488 } 3489 return false; 3490} 3491 3492 3493/* Worker for DEF_BUILTIN. 3494 Possibly define a builtin function with one or two names. 3495 Does not declare a non-__builtin_ function if flag_no_builtin, or if 3496 nonansi_p and flag_no_nonansi_builtin. */ 3497 3498static void 3499def_builtin_1 (enum built_in_function fncode, 3500 const char *name, 3501 enum built_in_class fnclass, 3502 tree fntype, tree libtype, 3503 bool both_p, bool fallback_p, bool nonansi_p, 3504 tree fnattrs, bool implicit_p) 3505{ 3506 tree decl; 3507 const char *libname; 3508 3509 if (fntype == error_mark_node) 3510 return; 3511 3512 gcc_assert ((!both_p && !fallback_p) 3513 || !strncmp (name, "__builtin_", 3514 strlen ("__builtin_"))); 3515 3516 libname = name + strlen ("__builtin_"); 3517 decl = lang_hooks.builtin_function (name, fntype, fncode, fnclass, 3518 (fallback_p ? libname : NULL), 3519 fnattrs); 3520 if (both_p 3521 && !flag_no_builtin && !builtin_function_disabled_p (libname) 3522 && !(nonansi_p && flag_no_nonansi_builtin)) 3523 lang_hooks.builtin_function (libname, libtype, fncode, fnclass, 3524 NULL, fnattrs); 3525 3526 built_in_decls[(int) fncode] = decl; 3527 if (implicit_p) 3528 implicit_built_in_decls[(int) fncode] = decl; 3529} 3530 3531/* Nonzero if the type T promotes to int. This is (nearly) the 3532 integral promotions defined in ISO C99 6.3.1.1/2. */ 3533 3534bool 3535c_promoting_integer_type_p (tree t) 3536{ 3537 switch (TREE_CODE (t)) 3538 { 3539 case INTEGER_TYPE: 3540 return (TYPE_MAIN_VARIANT (t) == char_type_node 3541 || TYPE_MAIN_VARIANT (t) == signed_char_type_node 3542 || TYPE_MAIN_VARIANT (t) == unsigned_char_type_node 3543 || TYPE_MAIN_VARIANT (t) == short_integer_type_node 3544 || TYPE_MAIN_VARIANT (t) == short_unsigned_type_node 3545 || TYPE_PRECISION (t) < TYPE_PRECISION (integer_type_node)); 3546 3547 case ENUMERAL_TYPE: 3548 /* ??? Technically all enumerations not larger than an int 3549 promote to an int. But this is used along code paths 3550 that only want to notice a size change. */ 3551 return TYPE_PRECISION (t) < TYPE_PRECISION (integer_type_node); 3552 3553 case BOOLEAN_TYPE: 3554 return 1; 3555 3556 default: 3557 return 0; 3558 } 3559} 3560 3561/* Return 1 if PARMS specifies a fixed number of parameters 3562 and none of their types is affected by default promotions. */ 3563 3564int 3565self_promoting_args_p (tree parms) 3566{ 3567 tree t; 3568 for (t = parms; t; t = TREE_CHAIN (t)) 3569 { 3570 tree type = TREE_VALUE (t); 3571 3572 if (type == error_mark_node) 3573 continue; 3574 3575 if (TREE_CHAIN (t) == 0 && type != void_type_node) 3576 return 0; 3577 3578 if (type == 0) 3579 return 0; 3580 3581 if (TYPE_MAIN_VARIANT (type) == float_type_node) 3582 return 0; 3583 3584 if (c_promoting_integer_type_p (type)) 3585 return 0; 3586 } 3587 return 1; 3588} 3589 3590/* Recursively examines the array elements of TYPE, until a non-array 3591 element type is found. */ 3592 3593tree 3594strip_array_types (tree type) 3595{ 3596 while (TREE_CODE (type) == ARRAY_TYPE) 3597 type = TREE_TYPE (type); 3598 3599 return type; 3600} 3601 3602/* Recursively remove any '*' or '&' operator from TYPE. */ 3603tree 3604strip_pointer_operator (tree t) 3605{ 3606 while (POINTER_TYPE_P (t)) 3607 t = TREE_TYPE (t); 3608 return t; 3609} 3610 3611/* Used to compare case labels. K1 and K2 are actually tree nodes 3612 representing case labels, or NULL_TREE for a `default' label. 3613 Returns -1 if K1 is ordered before K2, -1 if K1 is ordered after 3614 K2, and 0 if K1 and K2 are equal. */ 3615 3616int 3617case_compare (splay_tree_key k1, splay_tree_key k2) 3618{ 3619 /* Consider a NULL key (such as arises with a `default' label) to be 3620 smaller than anything else. */ 3621 if (!k1) 3622 return k2 ? -1 : 0; 3623 else if (!k2) 3624 return k1 ? 1 : 0; 3625 3626 return tree_int_cst_compare ((tree) k1, (tree) k2); 3627} 3628 3629/* Process a case label for the range LOW_VALUE ... HIGH_VALUE. If 3630 LOW_VALUE and HIGH_VALUE are both NULL_TREE then this case label is 3631 actually a `default' label. If only HIGH_VALUE is NULL_TREE, then 3632 case label was declared using the usual C/C++ syntax, rather than 3633 the GNU case range extension. CASES is a tree containing all the 3634 case ranges processed so far; COND is the condition for the 3635 switch-statement itself. Returns the CASE_LABEL_EXPR created, or 3636 ERROR_MARK_NODE if no CASE_LABEL_EXPR is created. */ 3637 3638tree 3639c_add_case_label (splay_tree cases, tree cond, tree orig_type, 3640 tree low_value, tree high_value) 3641{ 3642 tree type; 3643 tree label; 3644 tree case_label; 3645 splay_tree_node node; 3646 3647 /* Create the LABEL_DECL itself. */ 3648 label = create_artificial_label (); 3649 3650 /* If there was an error processing the switch condition, bail now 3651 before we get more confused. */ 3652 if (!cond || cond == error_mark_node) 3653 goto error_out; 3654 3655 if ((low_value && TREE_TYPE (low_value) 3656 && POINTER_TYPE_P (TREE_TYPE (low_value))) 3657 || (high_value && TREE_TYPE (high_value) 3658 && POINTER_TYPE_P (TREE_TYPE (high_value)))) 3659 { 3660 error ("pointers are not permitted as case values"); 3661 goto error_out; 3662 } 3663 3664 /* Case ranges are a GNU extension. */ 3665 if (high_value && pedantic) 3666 pedwarn ("range expressions in switch statements are non-standard"); 3667 3668 type = TREE_TYPE (cond); 3669 if (low_value) 3670 { 3671 low_value = check_case_value (low_value); 3672 low_value = convert_and_check (type, low_value); 3673 if (low_value == error_mark_node) 3674 goto error_out; 3675 } 3676 if (high_value) 3677 { 3678 high_value = check_case_value (high_value); 3679 high_value = convert_and_check (type, high_value); 3680 if (high_value == error_mark_node) 3681 goto error_out; 3682 } 3683 3684 if (low_value && high_value) 3685 { 3686 /* If the LOW_VALUE and HIGH_VALUE are the same, then this isn't 3687 really a case range, even though it was written that way. 3688 Remove the HIGH_VALUE to simplify later processing. */ 3689 if (tree_int_cst_equal (low_value, high_value)) 3690 high_value = NULL_TREE; 3691 else if (!tree_int_cst_lt (low_value, high_value)) 3692 warning (0, "empty range specified"); 3693 } 3694 3695 /* See if the case is in range of the type of the original testing 3696 expression. If both low_value and high_value are out of range, 3697 don't insert the case label and return NULL_TREE. */ 3698 if (low_value 3699 && !check_case_bounds (type, orig_type, 3700 &low_value, high_value ? &high_value : NULL)) 3701 return NULL_TREE; 3702 3703 /* Look up the LOW_VALUE in the table of case labels we already 3704 have. */ 3705 node = splay_tree_lookup (cases, (splay_tree_key) low_value); 3706 /* If there was not an exact match, check for overlapping ranges. 3707 There's no need to do this if there's no LOW_VALUE or HIGH_VALUE; 3708 that's a `default' label and the only overlap is an exact match. */ 3709 if (!node && (low_value || high_value)) 3710 { 3711 splay_tree_node low_bound; 3712 splay_tree_node high_bound; 3713 3714 /* Even though there wasn't an exact match, there might be an 3715 overlap between this case range and another case range. 3716 Since we've (inductively) not allowed any overlapping case 3717 ranges, we simply need to find the greatest low case label 3718 that is smaller that LOW_VALUE, and the smallest low case 3719 label that is greater than LOW_VALUE. If there is an overlap 3720 it will occur in one of these two ranges. */ 3721 low_bound = splay_tree_predecessor (cases, 3722 (splay_tree_key) low_value); 3723 high_bound = splay_tree_successor (cases, 3724 (splay_tree_key) low_value); 3725 3726 /* Check to see if the LOW_BOUND overlaps. It is smaller than 3727 the LOW_VALUE, so there is no need to check unless the 3728 LOW_BOUND is in fact itself a case range. */ 3729 if (low_bound 3730 && CASE_HIGH ((tree) low_bound->value) 3731 && tree_int_cst_compare (CASE_HIGH ((tree) low_bound->value), 3732 low_value) >= 0) 3733 node = low_bound; 3734 /* Check to see if the HIGH_BOUND overlaps. The low end of that 3735 range is bigger than the low end of the current range, so we 3736 are only interested if the current range is a real range, and 3737 not an ordinary case label. */ 3738 else if (high_bound 3739 && high_value 3740 && (tree_int_cst_compare ((tree) high_bound->key, 3741 high_value) 3742 <= 0)) 3743 node = high_bound; 3744 } 3745 /* If there was an overlap, issue an error. */ 3746 if (node) 3747 { 3748 tree duplicate = CASE_LABEL ((tree) node->value); 3749 3750 if (high_value) 3751 { 3752 error ("duplicate (or overlapping) case value"); 3753 error ("%Jthis is the first entry overlapping that value", duplicate); 3754 } 3755 else if (low_value) 3756 { 3757 error ("duplicate case value") ; 3758 error ("%Jpreviously used here", duplicate); 3759 } 3760 else 3761 { 3762 error ("multiple default labels in one switch"); 3763 error ("%Jthis is the first default label", duplicate); 3764 } 3765 goto error_out; 3766 } 3767 3768 /* Add a CASE_LABEL to the statement-tree. */ 3769 case_label = add_stmt (build_case_label (low_value, high_value, label)); 3770 /* Register this case label in the splay tree. */ 3771 splay_tree_insert (cases, 3772 (splay_tree_key) low_value, 3773 (splay_tree_value) case_label); 3774 3775 return case_label; 3776 3777 error_out: 3778 /* Add a label so that the back-end doesn't think that the beginning of 3779 the switch is unreachable. Note that we do not add a case label, as 3780 that just leads to duplicates and thence to failure later on. */ 3781 if (!cases->root) 3782 { 3783 tree t = create_artificial_label (); 3784 add_stmt (build_stmt (LABEL_EXPR, t)); 3785 } 3786 return error_mark_node; 3787} 3788 3789/* Subroutines of c_do_switch_warnings, called via splay_tree_foreach. 3790 Used to verify that case values match up with enumerator values. */ 3791 3792static void 3793match_case_to_enum_1 (tree key, tree type, tree label) 3794{ 3795 char buf[2 + 2*HOST_BITS_PER_WIDE_INT/4 + 1]; 3796 3797 /* ??? Not working too hard to print the double-word value. 3798 Should perhaps be done with %lwd in the diagnostic routines? */ 3799 if (TREE_INT_CST_HIGH (key) == 0) 3800 snprintf (buf, sizeof (buf), HOST_WIDE_INT_PRINT_UNSIGNED, 3801 TREE_INT_CST_LOW (key)); 3802 else if (!TYPE_UNSIGNED (type) 3803 && TREE_INT_CST_HIGH (key) == -1 3804 && TREE_INT_CST_LOW (key) != 0) 3805 snprintf (buf, sizeof (buf), "-" HOST_WIDE_INT_PRINT_UNSIGNED, 3806 -TREE_INT_CST_LOW (key)); 3807 else 3808 snprintf (buf, sizeof (buf), HOST_WIDE_INT_PRINT_DOUBLE_HEX, 3809 TREE_INT_CST_HIGH (key), TREE_INT_CST_LOW (key)); 3810 3811 if (TYPE_NAME (type) == 0) 3812 warning (0, "%Jcase value %qs not in enumerated type", 3813 CASE_LABEL (label), buf); 3814 else 3815 warning (0, "%Jcase value %qs not in enumerated type %qT", 3816 CASE_LABEL (label), buf, type); 3817} 3818 3819/* Subroutine of c_do_switch_warnings, called via splay_tree_foreach. 3820 Used to verify that case values match up with enumerator values. */ 3821 3822static int 3823match_case_to_enum (splay_tree_node node, void *data) 3824{ 3825 tree label = (tree) node->value; 3826 tree type = (tree) data; 3827 3828 /* Skip default case. */ 3829 if (!CASE_LOW (label)) 3830 return 0; 3831 3832 /* If CASE_LOW_SEEN is not set, that means CASE_LOW did not appear 3833 when we did our enum->case scan. Reset our scratch bit after. */ 3834 if (!CASE_LOW_SEEN (label)) 3835 match_case_to_enum_1 (CASE_LOW (label), type, label); 3836 else 3837 CASE_LOW_SEEN (label) = 0; 3838 3839 /* If CASE_HIGH is non-null, we have a range. If CASE_HIGH_SEEN is 3840 not set, that means that CASE_HIGH did not appear when we did our 3841 enum->case scan. Reset our scratch bit after. */ 3842 if (CASE_HIGH (label)) 3843 { 3844 if (!CASE_HIGH_SEEN (label)) 3845 match_case_to_enum_1 (CASE_HIGH (label), type, label); 3846 else 3847 CASE_HIGH_SEEN (label) = 0; 3848 } 3849 3850 return 0; 3851} 3852 3853/* Handle -Wswitch*. Called from the front end after parsing the 3854 switch construct. */ 3855/* ??? Should probably be somewhere generic, since other languages 3856 besides C and C++ would want this. At the moment, however, C/C++ 3857 are the only tree-ssa languages that support enumerations at all, 3858 so the point is moot. */ 3859 3860void 3861c_do_switch_warnings (splay_tree cases, location_t switch_location, 3862 tree type, tree cond) 3863{ 3864 splay_tree_node default_node; 3865 splay_tree_node node; 3866 tree chain; 3867 3868 if (!warn_switch && !warn_switch_enum && !warn_switch_default) 3869 return; 3870 3871 default_node = splay_tree_lookup (cases, (splay_tree_key) NULL); 3872 if (!default_node) 3873 warning (OPT_Wswitch_default, "%Hswitch missing default case", 3874 &switch_location); 3875 3876 /* From here on, we only care about about enumerated types. */ 3877 if (!type || TREE_CODE (type) != ENUMERAL_TYPE) 3878 return; 3879 3880 /* If the switch expression was an enumerated type, check that 3881 exactly all enumeration literals are covered by the cases. 3882 The check is made when -Wswitch was specified and there is no 3883 default case, or when -Wswitch-enum was specified. */ 3884 3885 if (!warn_switch_enum 3886 && !(warn_switch && !default_node)) 3887 return; 3888 3889 /* Clearing COND if it is not an integer constant simplifies 3890 the tests inside the loop below. */ 3891 if (TREE_CODE (cond) != INTEGER_CST) 3892 cond = NULL_TREE; 3893 3894 /* The time complexity here is O(N*lg(N)) worst case, but for the 3895 common case of monotonically increasing enumerators, it is 3896 O(N), since the nature of the splay tree will keep the next 3897 element adjacent to the root at all times. */ 3898 3899 for (chain = TYPE_VALUES (type); chain; chain = TREE_CHAIN (chain)) 3900 { 3901 tree value = TREE_VALUE (chain); 3902 node = splay_tree_lookup (cases, (splay_tree_key) value); 3903 if (node) 3904 { 3905 /* Mark the CASE_LOW part of the case entry as seen. */ 3906 tree label = (tree) node->value; 3907 CASE_LOW_SEEN (label) = 1; 3908 continue; 3909 } 3910 3911 /* Even though there wasn't an exact match, there might be a 3912 case range which includes the enumator's value. */ 3913 node = splay_tree_predecessor (cases, (splay_tree_key) value); 3914 if (node && CASE_HIGH ((tree) node->value)) 3915 { 3916 tree label = (tree) node->value; 3917 int cmp = tree_int_cst_compare (CASE_HIGH (label), value); 3918 if (cmp >= 0) 3919 { 3920 /* If we match the upper bound exactly, mark the CASE_HIGH 3921 part of the case entry as seen. */ 3922 if (cmp == 0) 3923 CASE_HIGH_SEEN (label) = 1; 3924 continue; 3925 } 3926 } 3927 3928 /* We've now determined that this enumerated literal isn't 3929 handled by the case labels of the switch statement. */ 3930 3931 /* If the switch expression is a constant, we only really care 3932 about whether that constant is handled by the switch. */ 3933 if (cond && tree_int_cst_compare (cond, value)) 3934 continue; 3935 3936 warning (0, "%Henumeration value %qE not handled in switch", 3937 &switch_location, TREE_PURPOSE (chain)); 3938 } 3939 3940 /* Warn if there are case expressions that don't correspond to 3941 enumerators. This can occur since C and C++ don't enforce 3942 type-checking of assignments to enumeration variables. 3943 3944 The time complexity here is now always O(N) worst case, since 3945 we should have marked both the lower bound and upper bound of 3946 every disjoint case label, with CASE_LOW_SEEN and CASE_HIGH_SEEN 3947 above. This scan also resets those fields. */ 3948 splay_tree_foreach (cases, match_case_to_enum, type); 3949} 3950 3951/* Finish an expression taking the address of LABEL (an 3952 IDENTIFIER_NODE). Returns an expression for the address. */ 3953 3954tree 3955finish_label_address_expr (tree label) 3956{ 3957 tree result; 3958 3959 if (pedantic) 3960 pedwarn ("taking the address of a label is non-standard"); 3961 3962 if (label == error_mark_node) 3963 return error_mark_node; 3964 3965 label = lookup_label (label); 3966 if (label == NULL_TREE) 3967 result = null_pointer_node; 3968 else 3969 { 3970 TREE_USED (label) = 1; 3971 result = build1 (ADDR_EXPR, ptr_type_node, label); 3972 /* The current function in not necessarily uninlinable. 3973 Computed gotos are incompatible with inlining, but the value 3974 here could be used only in a diagnostic, for example. */ 3975 } 3976 3977 return result; 3978} 3979 3980/* Hook used by expand_expr to expand language-specific tree codes. */ 3981/* The only things that should go here are bits needed to expand 3982 constant initializers. Everything else should be handled by the 3983 gimplification routines. */ 3984 3985rtx 3986c_expand_expr (tree exp, rtx target, enum machine_mode tmode, 3987 int modifier /* Actually enum_modifier. */, 3988 rtx *alt_rtl) 3989{ 3990 switch (TREE_CODE (exp)) 3991 { 3992 case COMPOUND_LITERAL_EXPR: 3993 { 3994 /* Initialize the anonymous variable declared in the compound 3995 literal, then return the variable. */ 3996 tree decl = COMPOUND_LITERAL_EXPR_DECL (exp); 3997 emit_local_var (decl); 3998 return expand_expr_real (decl, target, tmode, modifier, alt_rtl); 3999 } 4000 4001 default: 4002 gcc_unreachable (); 4003 } 4004} 4005 4006/* Hook used by staticp to handle language-specific tree codes. */ 4007 4008tree 4009c_staticp (tree exp) 4010{ 4011 return (TREE_CODE (exp) == COMPOUND_LITERAL_EXPR 4012 && TREE_STATIC (COMPOUND_LITERAL_EXPR_DECL (exp)) 4013 ? exp : NULL); 4014} 4015 4016 4017/* Given a boolean expression ARG, return a tree representing an increment 4018 or decrement (as indicated by CODE) of ARG. The front end must check for 4019 invalid cases (e.g., decrement in C++). */ 4020tree 4021boolean_increment (enum tree_code code, tree arg) 4022{ 4023 tree val; 4024 tree true_res = boolean_true_node; 4025 4026 arg = stabilize_reference (arg); 4027 switch (code) 4028 { 4029 case PREINCREMENT_EXPR: 4030 val = build2 (MODIFY_EXPR, TREE_TYPE (arg), arg, true_res); 4031 break; 4032 case POSTINCREMENT_EXPR: 4033 val = build2 (MODIFY_EXPR, TREE_TYPE (arg), arg, true_res); 4034 arg = save_expr (arg); 4035 val = build2 (COMPOUND_EXPR, TREE_TYPE (arg), val, arg); 4036 val = build2 (COMPOUND_EXPR, TREE_TYPE (arg), arg, val); 4037 break; 4038 case PREDECREMENT_EXPR: 4039 val = build2 (MODIFY_EXPR, TREE_TYPE (arg), arg, 4040 invert_truthvalue (arg)); 4041 break; 4042 case POSTDECREMENT_EXPR: 4043 val = build2 (MODIFY_EXPR, TREE_TYPE (arg), arg, 4044 invert_truthvalue (arg)); 4045 arg = save_expr (arg); 4046 val = build2 (COMPOUND_EXPR, TREE_TYPE (arg), val, arg); 4047 val = build2 (COMPOUND_EXPR, TREE_TYPE (arg), arg, val); 4048 break; 4049 default: 4050 gcc_unreachable (); 4051 } 4052 TREE_SIDE_EFFECTS (val) = 1; 4053 return val; 4054} 4055 4056/* Built-in macros for stddef.h, that require macros defined in this 4057 file. */ 4058void 4059c_stddef_cpp_builtins(void) 4060{ 4061 builtin_define_with_value ("__SIZE_TYPE__", SIZE_TYPE, 0); 4062 builtin_define_with_value ("__PTRDIFF_TYPE__", PTRDIFF_TYPE, 0); 4063 builtin_define_with_value ("__WCHAR_TYPE__", MODIFIED_WCHAR_TYPE, 0); 4064 builtin_define_with_value ("__WINT_TYPE__", WINT_TYPE, 0); 4065 builtin_define_with_value ("__INTMAX_TYPE__", INTMAX_TYPE, 0); 4066 builtin_define_with_value ("__UINTMAX_TYPE__", UINTMAX_TYPE, 0); 4067} 4068 4069static void 4070c_init_attributes (void) 4071{ 4072 /* Fill in the built_in_attributes array. */ 4073#define DEF_ATTR_NULL_TREE(ENUM) \ 4074 built_in_attributes[(int) ENUM] = NULL_TREE; 4075#define DEF_ATTR_INT(ENUM, VALUE) \ 4076 built_in_attributes[(int) ENUM] = build_int_cst (NULL_TREE, VALUE); 4077#define DEF_ATTR_IDENT(ENUM, STRING) \ 4078 built_in_attributes[(int) ENUM] = get_identifier (STRING); 4079#define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) \ 4080 built_in_attributes[(int) ENUM] \ 4081 = tree_cons (built_in_attributes[(int) PURPOSE], \ 4082 built_in_attributes[(int) VALUE], \ 4083 built_in_attributes[(int) CHAIN]); 4084#include "builtin-attrs.def" 4085#undef DEF_ATTR_NULL_TREE 4086#undef DEF_ATTR_INT 4087#undef DEF_ATTR_IDENT 4088#undef DEF_ATTR_TREE_LIST 4089} 4090 4091/* Attribute handlers common to C front ends. */ 4092 4093/* Handle a "packed" attribute; arguments as in 4094 struct attribute_spec.handler. */ 4095 4096static tree 4097handle_packed_attribute (tree *node, tree name, tree ARG_UNUSED (args), 4098 int flags, bool *no_add_attrs) 4099{ 4100 if (TYPE_P (*node)) 4101 { 4102 if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE)) 4103 *node = build_variant_type_copy (*node); 4104 TYPE_PACKED (*node) = 1; 4105 } 4106 else if (TREE_CODE (*node) == FIELD_DECL) 4107 { 4108 if (TYPE_ALIGN (TREE_TYPE (*node)) <= BITS_PER_UNIT) 4109 warning (OPT_Wattributes, 4110 "%qE attribute ignored for field of type %qT", 4111 name, TREE_TYPE (*node)); 4112 else 4113 DECL_PACKED (*node) = 1; 4114 } 4115 /* We can't set DECL_PACKED for a VAR_DECL, because the bit is 4116 used for DECL_REGISTER. It wouldn't mean anything anyway. 4117 We can't set DECL_PACKED on the type of a TYPE_DECL, because 4118 that changes what the typedef is typing. */ 4119 else 4120 { 4121 warning (OPT_Wattributes, "%qE attribute ignored", name); 4122 *no_add_attrs = true; 4123 } 4124 4125 return NULL_TREE; 4126} 4127 4128/* Handle a "nocommon" attribute; arguments as in 4129 struct attribute_spec.handler. */ 4130 4131static tree 4132handle_nocommon_attribute (tree *node, tree name, 4133 tree ARG_UNUSED (args), 4134 int ARG_UNUSED (flags), bool *no_add_attrs) 4135{ 4136 if (TREE_CODE (*node) == VAR_DECL) 4137 DECL_COMMON (*node) = 0; 4138 else 4139 { 4140 warning (OPT_Wattributes, "%qE attribute ignored", name); 4141 *no_add_attrs = true; 4142 } 4143 4144 return NULL_TREE; 4145} 4146 4147/* Handle a "common" attribute; arguments as in 4148 struct attribute_spec.handler. */ 4149 4150static tree 4151handle_common_attribute (tree *node, tree name, tree ARG_UNUSED (args), 4152 int ARG_UNUSED (flags), bool *no_add_attrs) 4153{ 4154 if (TREE_CODE (*node) == VAR_DECL) 4155 DECL_COMMON (*node) = 1; 4156 else 4157 { 4158 warning (OPT_Wattributes, "%qE attribute ignored", name); 4159 *no_add_attrs = true; 4160 } 4161 4162 return NULL_TREE; 4163} 4164 4165/* Handle a "noreturn" attribute; arguments as in 4166 struct attribute_spec.handler. */ 4167 4168static tree 4169handle_noreturn_attribute (tree *node, tree name, tree ARG_UNUSED (args), 4170 int ARG_UNUSED (flags), bool *no_add_attrs) 4171{ 4172 tree type = TREE_TYPE (*node); 4173 4174 /* See FIXME comment in c_common_attribute_table. */ 4175 if (TREE_CODE (*node) == FUNCTION_DECL) 4176 TREE_THIS_VOLATILE (*node) = 1; 4177 else if (TREE_CODE (type) == POINTER_TYPE 4178 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE) 4179 TREE_TYPE (*node) 4180 = build_pointer_type 4181 (build_type_variant (TREE_TYPE (type), 4182 TYPE_READONLY (TREE_TYPE (type)), 1)); 4183 else 4184 { 4185 warning (OPT_Wattributes, "%qE attribute ignored", name); 4186 *no_add_attrs = true; 4187 } 4188 4189 return NULL_TREE; 4190} 4191 4192/* Handle a "noinline" attribute; arguments as in 4193 struct attribute_spec.handler. */ 4194 4195static tree 4196handle_noinline_attribute (tree *node, tree name, 4197 tree ARG_UNUSED (args), 4198 int ARG_UNUSED (flags), bool *no_add_attrs) 4199{ 4200 if (TREE_CODE (*node) == FUNCTION_DECL) 4201 DECL_UNINLINABLE (*node) = 1; 4202 else 4203 { 4204 warning (OPT_Wattributes, "%qE attribute ignored", name); 4205 *no_add_attrs = true; 4206 } 4207 4208 return NULL_TREE; 4209} 4210 4211/* Handle a "always_inline" attribute; arguments as in 4212 struct attribute_spec.handler. */ 4213 4214static tree 4215handle_always_inline_attribute (tree *node, tree name, 4216 tree ARG_UNUSED (args), 4217 int ARG_UNUSED (flags), 4218 bool *no_add_attrs) 4219{ 4220 if (TREE_CODE (*node) == FUNCTION_DECL) 4221 { 4222 /* Do nothing else, just set the attribute. We'll get at 4223 it later with lookup_attribute. */ 4224 } 4225 else 4226 { 4227 warning (OPT_Wattributes, "%qE attribute ignored", name); 4228 *no_add_attrs = true; 4229 } 4230 4231 return NULL_TREE; 4232} 4233 4234/* Handle a "gnu_inline" attribute; arguments as in 4235 struct attribute_spec.handler. */ 4236 4237static tree 4238handle_gnu_inline_attribute (tree *node, tree name, 4239 tree ARG_UNUSED (args), 4240 int ARG_UNUSED (flags), 4241 bool *no_add_attrs) 4242{ 4243 if (TREE_CODE (*node) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (*node)) 4244 { 4245 /* Do nothing else, just set the attribute. We'll get at 4246 it later with lookup_attribute. */ 4247 } 4248 else 4249 { 4250 warning (OPT_Wattributes, "%qE attribute ignored", name); 4251 *no_add_attrs = true; 4252 } 4253 4254 return NULL_TREE; 4255} 4256 4257/* Handle a "flatten" attribute; arguments as in 4258 struct attribute_spec.handler. */ 4259 4260static tree 4261handle_flatten_attribute (tree *node, tree name, 4262 tree args ATTRIBUTE_UNUSED, 4263 int flags ATTRIBUTE_UNUSED, bool *no_add_attrs) 4264{ 4265 if (TREE_CODE (*node) == FUNCTION_DECL) 4266 /* Do nothing else, just set the attribute. We'll get at 4267 it later with lookup_attribute. */ 4268 ; 4269 else 4270 { 4271 warning (OPT_Wattributes, "%qE attribute ignored", name); 4272 *no_add_attrs = true; 4273 } 4274 4275 return NULL_TREE; 4276} 4277 4278 4279/* Handle a "used" attribute; arguments as in 4280 struct attribute_spec.handler. */ 4281 4282static tree 4283handle_used_attribute (tree *pnode, tree name, tree ARG_UNUSED (args), 4284 int ARG_UNUSED (flags), bool *no_add_attrs) 4285{ 4286 tree node = *pnode; 4287 4288 if (TREE_CODE (node) == FUNCTION_DECL 4289 || (TREE_CODE (node) == VAR_DECL && TREE_STATIC (node))) 4290 { 4291 TREE_USED (node) = 1; 4292 DECL_PRESERVE_P (node) = 1; 4293 } 4294 else 4295 { 4296 warning (OPT_Wattributes, "%qE attribute ignored", name); 4297 *no_add_attrs = true; 4298 } 4299 4300 return NULL_TREE; 4301} 4302 4303/* Handle a "unused" attribute; arguments as in 4304 struct attribute_spec.handler. */ 4305 4306static tree 4307handle_unused_attribute (tree *node, tree name, tree ARG_UNUSED (args), 4308 int flags, bool *no_add_attrs) 4309{ 4310 if (DECL_P (*node)) 4311 { 4312 tree decl = *node; 4313 4314 if (TREE_CODE (decl) == PARM_DECL 4315 || TREE_CODE (decl) == VAR_DECL 4316 || TREE_CODE (decl) == FUNCTION_DECL 4317 || TREE_CODE (decl) == LABEL_DECL 4318 || TREE_CODE (decl) == TYPE_DECL) 4319 TREE_USED (decl) = 1; 4320 else 4321 { 4322 warning (OPT_Wattributes, "%qE attribute ignored", name); 4323 *no_add_attrs = true; 4324 } 4325 } 4326 else 4327 { 4328 if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE)) 4329 *node = build_variant_type_copy (*node); 4330 TREE_USED (*node) = 1; 4331 } 4332 4333 return NULL_TREE; 4334} 4335 4336/* Handle a "externally_visible" attribute; arguments as in 4337 struct attribute_spec.handler. */ 4338 4339static tree 4340handle_externally_visible_attribute (tree *pnode, tree name, 4341 tree ARG_UNUSED (args), 4342 int ARG_UNUSED (flags), 4343 bool *no_add_attrs) 4344{ 4345 tree node = *pnode; 4346 4347 if (TREE_CODE (node) == FUNCTION_DECL || TREE_CODE (node) == VAR_DECL) 4348 { 4349 if ((!TREE_STATIC (node) && TREE_CODE (node) != FUNCTION_DECL 4350 && !DECL_EXTERNAL (node)) || !TREE_PUBLIC (node)) 4351 { 4352 warning (OPT_Wattributes, 4353 "%qE attribute have effect only on public objects", name); 4354 *no_add_attrs = true; 4355 } 4356 } 4357 else 4358 { 4359 warning (OPT_Wattributes, "%qE attribute ignored", name); 4360 *no_add_attrs = true; 4361 } 4362 4363 return NULL_TREE; 4364} 4365 4366/* Handle a "const" attribute; arguments as in 4367 struct attribute_spec.handler. */ 4368 4369static tree 4370handle_const_attribute (tree *node, tree name, tree ARG_UNUSED (args), 4371 int ARG_UNUSED (flags), bool *no_add_attrs) 4372{ 4373 tree type = TREE_TYPE (*node); 4374 4375 /* See FIXME comment on noreturn in c_common_attribute_table. */ 4376 if (TREE_CODE (*node) == FUNCTION_DECL) 4377 TREE_READONLY (*node) = 1; 4378 else if (TREE_CODE (type) == POINTER_TYPE 4379 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE) 4380 TREE_TYPE (*node) 4381 = build_pointer_type 4382 (build_type_variant (TREE_TYPE (type), 1, 4383 TREE_THIS_VOLATILE (TREE_TYPE (type)))); 4384 else 4385 { 4386 warning (OPT_Wattributes, "%qE attribute ignored", name); 4387 *no_add_attrs = true; 4388 } 4389 4390 return NULL_TREE; 4391} 4392 4393/* Handle a "transparent_union" attribute; arguments as in 4394 struct attribute_spec.handler. */ 4395 4396static tree 4397handle_transparent_union_attribute (tree *node, tree name, 4398 tree ARG_UNUSED (args), int flags, 4399 bool *no_add_attrs) 4400{ 4401 tree type = NULL; 4402 4403 *no_add_attrs = true; 4404 4405 if (DECL_P (*node)) 4406 { 4407 if (TREE_CODE (*node) != TYPE_DECL) 4408 goto ignored; 4409 node = &TREE_TYPE (*node); 4410 type = *node; 4411 } 4412 else if (TYPE_P (*node)) 4413 type = *node; 4414 else 4415 goto ignored; 4416 4417 if (TREE_CODE (type) == UNION_TYPE) 4418 { 4419 /* When IN_PLACE is set, leave the check for FIELDS and MODE to 4420 the code in finish_struct. */ 4421 if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE)) 4422 { 4423 if (TYPE_FIELDS (type) == NULL_TREE 4424 || TYPE_MODE (type) != DECL_MODE (TYPE_FIELDS (type))) 4425 goto ignored; 4426 4427 /* A type variant isn't good enough, since we don't a cast 4428 to such a type removed as a no-op. */ 4429 *node = type = build_duplicate_type (type); 4430 } 4431 4432 TYPE_TRANSPARENT_UNION (type) = 1; 4433 return NULL_TREE; 4434 } 4435 4436 ignored: 4437 warning (OPT_Wattributes, "%qE attribute ignored", name); 4438 return NULL_TREE; 4439} 4440 4441/* Handle a "constructor" attribute; arguments as in 4442 struct attribute_spec.handler. */ 4443 4444static tree 4445handle_constructor_attribute (tree *node, tree name, 4446 tree ARG_UNUSED (args), 4447 int ARG_UNUSED (flags), 4448 bool *no_add_attrs) 4449{ 4450 tree decl = *node; 4451 tree type = TREE_TYPE (decl); 4452 4453 if (TREE_CODE (decl) == FUNCTION_DECL 4454 && TREE_CODE (type) == FUNCTION_TYPE 4455 && decl_function_context (decl) == 0) 4456 { 4457 DECL_STATIC_CONSTRUCTOR (decl) = 1; 4458 TREE_USED (decl) = 1; 4459 } 4460 else 4461 { 4462 warning (OPT_Wattributes, "%qE attribute ignored", name); 4463 *no_add_attrs = true; 4464 } 4465 4466 return NULL_TREE; 4467} 4468 4469/* Handle a "destructor" attribute; arguments as in 4470 struct attribute_spec.handler. */ 4471 4472static tree 4473handle_destructor_attribute (tree *node, tree name, 4474 tree ARG_UNUSED (args), 4475 int ARG_UNUSED (flags), 4476 bool *no_add_attrs) 4477{ 4478 tree decl = *node; 4479 tree type = TREE_TYPE (decl); 4480 4481 if (TREE_CODE (decl) == FUNCTION_DECL 4482 && TREE_CODE (type) == FUNCTION_TYPE 4483 && decl_function_context (decl) == 0) 4484 { 4485 DECL_STATIC_DESTRUCTOR (decl) = 1; 4486 TREE_USED (decl) = 1; 4487 } 4488 else 4489 { 4490 warning (OPT_Wattributes, "%qE attribute ignored", name); 4491 *no_add_attrs = true; 4492 } 4493 4494 return NULL_TREE; 4495} 4496 4497/* Handle a "mode" attribute; arguments as in 4498 struct attribute_spec.handler. */ 4499 4500static tree 4501handle_mode_attribute (tree *node, tree name, tree args, 4502 int ARG_UNUSED (flags), bool *no_add_attrs) 4503{ 4504 tree type = *node; 4505 4506 *no_add_attrs = true; 4507 4508 if (TREE_CODE (TREE_VALUE (args)) != IDENTIFIER_NODE) 4509 warning (OPT_Wattributes, "%qE attribute ignored", name); 4510 else 4511 { 4512 int j; 4513 const char *p = IDENTIFIER_POINTER (TREE_VALUE (args)); 4514 int len = strlen (p); 4515 enum machine_mode mode = VOIDmode; 4516 tree typefm; 4517 bool valid_mode; 4518 4519 if (len > 4 && p[0] == '_' && p[1] == '_' 4520 && p[len - 1] == '_' && p[len - 2] == '_') 4521 { 4522 char *newp = (char *) alloca (len - 1); 4523 4524 strcpy (newp, &p[2]); 4525 newp[len - 4] = '\0'; 4526 p = newp; 4527 } 4528 4529 /* Change this type to have a type with the specified mode. 4530 First check for the special modes. */ 4531 if (!strcmp (p, "byte")) 4532 mode = byte_mode; 4533 else if (!strcmp (p, "word")) 4534 mode = word_mode; 4535 else if (!strcmp (p, "pointer")) 4536 mode = ptr_mode; 4537 else 4538 for (j = 0; j < NUM_MACHINE_MODES; j++) 4539 if (!strcmp (p, GET_MODE_NAME (j))) 4540 { 4541 mode = (enum machine_mode) j; 4542 break; 4543 } 4544 4545 if (mode == VOIDmode) 4546 { 4547 error ("unknown machine mode %qs", p); 4548 return NULL_TREE; 4549 } 4550 4551 valid_mode = false; 4552 switch (GET_MODE_CLASS (mode)) 4553 { 4554 case MODE_INT: 4555 case MODE_PARTIAL_INT: 4556 case MODE_FLOAT: 4557 case MODE_DECIMAL_FLOAT: 4558 valid_mode = targetm.scalar_mode_supported_p (mode); 4559 break; 4560 4561 case MODE_COMPLEX_INT: 4562 case MODE_COMPLEX_FLOAT: 4563 valid_mode = targetm.scalar_mode_supported_p (GET_MODE_INNER (mode)); 4564 break; 4565 4566 case MODE_VECTOR_INT: 4567 case MODE_VECTOR_FLOAT: 4568 warning (OPT_Wattributes, "specifying vector types with " 4569 "__attribute__ ((mode)) is deprecated"); 4570 warning (OPT_Wattributes, 4571 "use __attribute__ ((vector_size)) instead"); 4572 valid_mode = vector_mode_valid_p (mode); 4573 break; 4574 4575 default: 4576 break; 4577 } 4578 if (!valid_mode) 4579 { 4580 error ("unable to emulate %qs", p); 4581 return NULL_TREE; 4582 } 4583 4584 if (POINTER_TYPE_P (type)) 4585 { 4586 tree (*fn)(tree, enum machine_mode, bool); 4587 4588 if (!targetm.valid_pointer_mode (mode)) 4589 { 4590 error ("invalid pointer mode %qs", p); 4591 return NULL_TREE; 4592 } 4593 4594 if (TREE_CODE (type) == POINTER_TYPE) 4595 fn = build_pointer_type_for_mode; 4596 else 4597 fn = build_reference_type_for_mode; 4598 typefm = fn (TREE_TYPE (type), mode, false); 4599 } 4600 else 4601 typefm = lang_hooks.types.type_for_mode (mode, TYPE_UNSIGNED (type)); 4602 4603 if (typefm == NULL_TREE) 4604 { 4605 error ("no data type for mode %qs", p); 4606 return NULL_TREE; 4607 } 4608 else if (TREE_CODE (type) == ENUMERAL_TYPE) 4609 { 4610 /* For enumeral types, copy the precision from the integer 4611 type returned above. If not an INTEGER_TYPE, we can't use 4612 this mode for this type. */ 4613 if (TREE_CODE (typefm) != INTEGER_TYPE) 4614 { 4615 error ("cannot use mode %qs for enumeral types", p); 4616 return NULL_TREE; 4617 } 4618 4619 if (flags & ATTR_FLAG_TYPE_IN_PLACE) 4620 { 4621 TYPE_PRECISION (type) = TYPE_PRECISION (typefm); 4622 typefm = type; 4623 } 4624 else 4625 { 4626 /* We cannot build a type variant, as there's code that assumes 4627 that TYPE_MAIN_VARIANT has the same mode. This includes the 4628 debug generators. Instead, create a subrange type. This 4629 results in all of the enumeral values being emitted only once 4630 in the original, and the subtype gets them by reference. */ 4631 if (TYPE_UNSIGNED (type)) 4632 typefm = make_unsigned_type (TYPE_PRECISION (typefm)); 4633 else 4634 typefm = make_signed_type (TYPE_PRECISION (typefm)); 4635 TREE_TYPE (typefm) = type; 4636 } 4637 } 4638 else if (VECTOR_MODE_P (mode) 4639 ? TREE_CODE (type) != TREE_CODE (TREE_TYPE (typefm)) 4640 : TREE_CODE (type) != TREE_CODE (typefm)) 4641 { 4642 error ("mode %qs applied to inappropriate type", p); 4643 return NULL_TREE; 4644 } 4645 4646 *node = typefm; 4647 } 4648 4649 return NULL_TREE; 4650} 4651 4652/* Handle a "section" attribute; arguments as in 4653 struct attribute_spec.handler. */ 4654 4655static tree 4656handle_section_attribute (tree *node, tree ARG_UNUSED (name), tree args, 4657 int ARG_UNUSED (flags), bool *no_add_attrs) 4658{ 4659 tree decl = *node; 4660 4661 if (targetm.have_named_sections) 4662 { 4663 user_defined_section_attribute = true; 4664 4665 if ((TREE_CODE (decl) == FUNCTION_DECL 4666 || TREE_CODE (decl) == VAR_DECL) 4667 && TREE_CODE (TREE_VALUE (args)) == STRING_CST) 4668 { 4669 if (TREE_CODE (decl) == VAR_DECL 4670 && current_function_decl != NULL_TREE 4671 && !TREE_STATIC (decl)) 4672 { 4673 error ("%Jsection attribute cannot be specified for " 4674 "local variables", decl); 4675 *no_add_attrs = true; 4676 } 4677 4678 /* The decl may have already been given a section attribute 4679 from a previous declaration. Ensure they match. */ 4680 else if (DECL_SECTION_NAME (decl) != NULL_TREE 4681 && strcmp (TREE_STRING_POINTER (DECL_SECTION_NAME (decl)), 4682 TREE_STRING_POINTER (TREE_VALUE (args))) != 0) 4683 { 4684 error ("section of %q+D conflicts with previous declaration", 4685 *node); 4686 *no_add_attrs = true; 4687 } 4688 else 4689 DECL_SECTION_NAME (decl) = TREE_VALUE (args); 4690 } 4691 else 4692 { 4693 error ("section attribute not allowed for %q+D", *node); 4694 *no_add_attrs = true; 4695 } 4696 } 4697 else 4698 { 4699 error ("%Jsection attributes are not supported for this target", *node); 4700 *no_add_attrs = true; 4701 } 4702 4703 return NULL_TREE; 4704} 4705 4706/* Handle a "aligned" attribute; arguments as in 4707 struct attribute_spec.handler. */ 4708 4709static tree 4710handle_aligned_attribute (tree *node, tree ARG_UNUSED (name), tree args, 4711 int flags, bool *no_add_attrs) 4712{ 4713 tree decl = NULL_TREE; 4714 tree *type = NULL; 4715 int is_type = 0; 4716 tree align_expr = (args ? TREE_VALUE (args) 4717 : size_int (BIGGEST_ALIGNMENT / BITS_PER_UNIT)); 4718 int i; 4719 4720 if (DECL_P (*node)) 4721 { 4722 decl = *node; 4723 type = &TREE_TYPE (decl); 4724 is_type = TREE_CODE (*node) == TYPE_DECL; 4725 } 4726 else if (TYPE_P (*node)) 4727 type = node, is_type = 1; 4728 4729 if (TREE_CODE (align_expr) != INTEGER_CST) 4730 { 4731 error ("requested alignment is not a constant"); 4732 *no_add_attrs = true; 4733 } 4734 else if ((i = tree_log2 (align_expr)) == -1) 4735 { 4736 error ("requested alignment is not a power of 2"); 4737 *no_add_attrs = true; 4738 } 4739 else if (i > HOST_BITS_PER_INT - 2) 4740 { 4741 error ("requested alignment is too large"); 4742 *no_add_attrs = true; 4743 } 4744 else if (is_type) 4745 { 4746 /* If we have a TYPE_DECL, then copy the type, so that we 4747 don't accidentally modify a builtin type. See pushdecl. */ 4748 if (decl && TREE_TYPE (decl) != error_mark_node 4749 && DECL_ORIGINAL_TYPE (decl) == NULL_TREE) 4750 { 4751 tree tt = TREE_TYPE (decl); 4752 *type = build_variant_type_copy (*type); 4753 DECL_ORIGINAL_TYPE (decl) = tt; 4754 TYPE_NAME (*type) = decl; 4755 TREE_USED (*type) = TREE_USED (decl); 4756 TREE_TYPE (decl) = *type; 4757 } 4758 else if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE)) 4759 *type = build_variant_type_copy (*type); 4760 4761 TYPE_ALIGN (*type) = (1 << i) * BITS_PER_UNIT; 4762 TYPE_USER_ALIGN (*type) = 1; 4763 } 4764 else if (TREE_CODE (decl) != VAR_DECL 4765 && TREE_CODE (decl) != FIELD_DECL) 4766 { 4767 error ("alignment may not be specified for %q+D", decl); 4768 *no_add_attrs = true; 4769 } 4770 else 4771 { 4772 DECL_ALIGN (decl) = (1 << i) * BITS_PER_UNIT; 4773 DECL_USER_ALIGN (decl) = 1; 4774 } 4775 4776 return NULL_TREE; 4777} 4778 4779/* Handle a "weak" attribute; arguments as in 4780 struct attribute_spec.handler. */ 4781 4782static tree 4783handle_weak_attribute (tree *node, tree name, 4784 tree ARG_UNUSED (args), 4785 int ARG_UNUSED (flags), 4786 bool * ARG_UNUSED (no_add_attrs)) 4787{ 4788 if (TREE_CODE (*node) == FUNCTION_DECL 4789 || TREE_CODE (*node) == VAR_DECL) 4790 declare_weak (*node); 4791 else 4792 warning (OPT_Wattributes, "%qE attribute ignored", name); 4793 4794 4795 return NULL_TREE; 4796} 4797 4798/* Handle an "alias" attribute; arguments as in 4799 struct attribute_spec.handler. */ 4800 4801static tree 4802handle_alias_attribute (tree *node, tree name, tree args, 4803 int ARG_UNUSED (flags), bool *no_add_attrs) 4804{ 4805 tree decl = *node; 4806 4807 if ((TREE_CODE (decl) == FUNCTION_DECL && DECL_INITIAL (decl)) 4808 || (TREE_CODE (decl) != FUNCTION_DECL 4809 && TREE_PUBLIC (decl) && !DECL_EXTERNAL (decl)) 4810 /* A static variable declaration is always a tentative definition, 4811 but the alias is a non-tentative definition which overrides. */ 4812 || (TREE_CODE (decl) != FUNCTION_DECL 4813 && ! TREE_PUBLIC (decl) && DECL_INITIAL (decl))) 4814 { 4815 error ("%q+D defined both normally and as an alias", decl); 4816 *no_add_attrs = true; 4817 } 4818 4819 /* Note that the very first time we process a nested declaration, 4820 decl_function_context will not be set. Indeed, *would* never 4821 be set except for the DECL_INITIAL/DECL_EXTERNAL frobbery that 4822 we do below. After such frobbery, pushdecl would set the context. 4823 In any case, this is never what we want. */ 4824 else if (decl_function_context (decl) == 0 && current_function_decl == NULL) 4825 { 4826 tree id; 4827 4828 id = TREE_VALUE (args); 4829 if (TREE_CODE (id) != STRING_CST) 4830 { 4831 error ("alias argument not a string"); 4832 *no_add_attrs = true; 4833 return NULL_TREE; 4834 } 4835 id = get_identifier (TREE_STRING_POINTER (id)); 4836 /* This counts as a use of the object pointed to. */ 4837 TREE_USED (id) = 1; 4838 4839 if (TREE_CODE (decl) == FUNCTION_DECL) 4840 DECL_INITIAL (decl) = error_mark_node; 4841 else 4842 { 4843 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl))) 4844 DECL_EXTERNAL (decl) = 1; 4845 else 4846 DECL_EXTERNAL (decl) = 0; 4847 TREE_STATIC (decl) = 1; 4848 } 4849 } 4850 else 4851 { 4852 warning (OPT_Wattributes, "%qE attribute ignored", name); 4853 *no_add_attrs = true; 4854 } 4855 4856 return NULL_TREE; 4857} 4858 4859/* Handle a "weakref" attribute; arguments as in struct 4860 attribute_spec.handler. */ 4861 4862static tree 4863handle_weakref_attribute (tree *node, tree ARG_UNUSED (name), tree args, 4864 int flags, bool *no_add_attrs) 4865{ 4866 tree attr = NULL_TREE; 4867 4868 /* We must ignore the attribute when it is associated with 4869 local-scoped decls, since attribute alias is ignored and many 4870 such symbols do not even have a DECL_WEAK field. */ 4871 if (decl_function_context (*node) || current_function_decl) 4872 { 4873 warning (OPT_Wattributes, "%qE attribute ignored", name); 4874 *no_add_attrs = true; 4875 return NULL_TREE; 4876 } 4877 4878 /* The idea here is that `weakref("name")' mutates into `weakref, 4879 alias("name")', and weakref without arguments, in turn, 4880 implicitly adds weak. */ 4881 4882 if (args) 4883 { 4884 attr = tree_cons (get_identifier ("alias"), args, attr); 4885 attr = tree_cons (get_identifier ("weakref"), NULL_TREE, attr); 4886 4887 *no_add_attrs = true; 4888 4889 decl_attributes (node, attr, flags); 4890 } 4891 else 4892 { 4893 if (lookup_attribute ("alias", DECL_ATTRIBUTES (*node))) 4894 error ("%Jweakref attribute must appear before alias attribute", 4895 *node); 4896 4897 /* Can't call declare_weak because it wants this to be TREE_PUBLIC, 4898 and that isn't supported; and because it wants to add it to 4899 the list of weak decls, which isn't helpful. */ 4900 DECL_WEAK (*node) = 1; 4901 } 4902 4903 return NULL_TREE; 4904} 4905 4906/* Handle an "visibility" attribute; arguments as in 4907 struct attribute_spec.handler. */ 4908 4909static tree 4910handle_visibility_attribute (tree *node, tree name, tree args, 4911 int ARG_UNUSED (flags), 4912 bool *ARG_UNUSED (no_add_attrs)) 4913{ 4914 tree decl = *node; 4915 tree id = TREE_VALUE (args); 4916 enum symbol_visibility vis; 4917 4918 if (TYPE_P (*node)) 4919 { 4920 if (TREE_CODE (*node) == ENUMERAL_TYPE) 4921 /* OK */; 4922 else if (TREE_CODE (*node) != RECORD_TYPE && TREE_CODE (*node) != UNION_TYPE) 4923 { 4924 warning (OPT_Wattributes, "%qE attribute ignored on non-class types", 4925 name); 4926 return NULL_TREE; 4927 } 4928 else if (TYPE_FIELDS (*node)) 4929 { 4930 error ("%qE attribute ignored because %qT is already defined", 4931 name, *node); 4932 return NULL_TREE; 4933 } 4934 } 4935 else if (decl_function_context (decl) != 0 || !TREE_PUBLIC (decl)) 4936 { 4937 warning (OPT_Wattributes, "%qE attribute ignored", name); 4938 return NULL_TREE; 4939 } 4940 4941 if (TREE_CODE (id) != STRING_CST) 4942 { 4943 error ("visibility argument not a string"); 4944 return NULL_TREE; 4945 } 4946 4947 /* If this is a type, set the visibility on the type decl. */ 4948 if (TYPE_P (decl)) 4949 { 4950 decl = TYPE_NAME (decl); 4951 if (!decl) 4952 return NULL_TREE; 4953 if (TREE_CODE (decl) == IDENTIFIER_NODE) 4954 { 4955 warning (OPT_Wattributes, "%qE attribute ignored on types", 4956 name); 4957 return NULL_TREE; 4958 } 4959 } 4960 4961 if (strcmp (TREE_STRING_POINTER (id), "default") == 0) 4962 vis = VISIBILITY_DEFAULT; 4963 else if (strcmp (TREE_STRING_POINTER (id), "internal") == 0) 4964 vis = VISIBILITY_INTERNAL; 4965 else if (strcmp (TREE_STRING_POINTER (id), "hidden") == 0) 4966 vis = VISIBILITY_HIDDEN; 4967 else if (strcmp (TREE_STRING_POINTER (id), "protected") == 0) 4968 vis = VISIBILITY_PROTECTED; 4969 else 4970 { 4971 error ("visibility argument must be one of \"default\", \"hidden\", \"protected\" or \"internal\""); 4972 vis = VISIBILITY_DEFAULT; 4973 } 4974 4975 if (DECL_VISIBILITY_SPECIFIED (decl) 4976 && vis != DECL_VISIBILITY (decl) 4977 && lookup_attribute ("visibility", (TYPE_P (*node) 4978 ? TYPE_ATTRIBUTES (*node) 4979 : DECL_ATTRIBUTES (decl)))) 4980 error ("%qD redeclared with different visibility", decl); 4981 4982 DECL_VISIBILITY (decl) = vis; 4983 DECL_VISIBILITY_SPECIFIED (decl) = 1; 4984 4985 /* Go ahead and attach the attribute to the node as well. This is needed 4986 so we can determine whether we have VISIBILITY_DEFAULT because the 4987 visibility was not specified, or because it was explicitly overridden 4988 from the containing scope. */ 4989 4990 return NULL_TREE; 4991} 4992 4993/* Determine the ELF symbol visibility for DECL, which is either a 4994 variable or a function. It is an error to use this function if a 4995 definition of DECL is not available in this translation unit. 4996 Returns true if the final visibility has been determined by this 4997 function; false if the caller is free to make additional 4998 modifications. */ 4999 5000bool 5001c_determine_visibility (tree decl) 5002{ 5003 gcc_assert (TREE_CODE (decl) == VAR_DECL 5004 || TREE_CODE (decl) == FUNCTION_DECL); 5005 5006 /* If the user explicitly specified the visibility with an 5007 attribute, honor that. DECL_VISIBILITY will have been set during 5008 the processing of the attribute. We check for an explicit 5009 attribute, rather than just checking DECL_VISIBILITY_SPECIFIED, 5010 to distinguish the use of an attribute from the use of a "#pragma 5011 GCC visibility push(...)"; in the latter case we still want other 5012 considerations to be able to overrule the #pragma. */ 5013 if (lookup_attribute ("visibility", DECL_ATTRIBUTES (decl))) 5014 return true; 5015 5016 /* Anything that is exported must have default visibility. */ 5017 if (TARGET_DLLIMPORT_DECL_ATTRIBUTES 5018 && lookup_attribute ("dllexport", DECL_ATTRIBUTES (decl))) 5019 { 5020 DECL_VISIBILITY (decl) = VISIBILITY_DEFAULT; 5021 DECL_VISIBILITY_SPECIFIED (decl) = 1; 5022 return true; 5023 } 5024 5025 /* Set default visibility to whatever the user supplied with 5026 visibility_specified depending on #pragma GCC visibility. */ 5027 if (!DECL_VISIBILITY_SPECIFIED (decl)) 5028 { 5029 DECL_VISIBILITY (decl) = default_visibility; 5030 DECL_VISIBILITY_SPECIFIED (decl) = visibility_options.inpragma; 5031 } 5032 return false; 5033} 5034 5035/* Handle an "tls_model" attribute; arguments as in 5036 struct attribute_spec.handler. */ 5037 5038static tree 5039handle_tls_model_attribute (tree *node, tree name, tree args, 5040 int ARG_UNUSED (flags), bool *no_add_attrs) 5041{ 5042 tree id; 5043 tree decl = *node; 5044 enum tls_model kind; 5045 5046 *no_add_attrs = true; 5047 5048 if (!DECL_THREAD_LOCAL_P (decl)) 5049 { 5050 warning (OPT_Wattributes, "%qE attribute ignored", name); 5051 return NULL_TREE; 5052 } 5053 5054 kind = DECL_TLS_MODEL (decl); 5055 id = TREE_VALUE (args); 5056 if (TREE_CODE (id) != STRING_CST) 5057 { 5058 error ("tls_model argument not a string"); 5059 return NULL_TREE; 5060 } 5061 5062 if (!strcmp (TREE_STRING_POINTER (id), "local-exec")) 5063 kind = TLS_MODEL_LOCAL_EXEC; 5064 else if (!strcmp (TREE_STRING_POINTER (id), "initial-exec")) 5065 kind = TLS_MODEL_INITIAL_EXEC; 5066 else if (!strcmp (TREE_STRING_POINTER (id), "local-dynamic")) 5067 kind = optimize ? TLS_MODEL_LOCAL_DYNAMIC : TLS_MODEL_GLOBAL_DYNAMIC; 5068 else if (!strcmp (TREE_STRING_POINTER (id), "global-dynamic")) 5069 kind = TLS_MODEL_GLOBAL_DYNAMIC; 5070 else 5071 error ("tls_model argument must be one of \"local-exec\", \"initial-exec\", \"local-dynamic\" or \"global-dynamic\""); 5072 5073 DECL_TLS_MODEL (decl) = kind; 5074 return NULL_TREE; 5075} 5076 5077/* Handle a "no_instrument_function" attribute; arguments as in 5078 struct attribute_spec.handler. */ 5079 5080static tree 5081handle_no_instrument_function_attribute (tree *node, tree name, 5082 tree ARG_UNUSED (args), 5083 int ARG_UNUSED (flags), 5084 bool *no_add_attrs) 5085{ 5086 tree decl = *node; 5087 5088 if (TREE_CODE (decl) != FUNCTION_DECL) 5089 { 5090 error ("%J%qE attribute applies only to functions", decl, name); 5091 *no_add_attrs = true; 5092 } 5093 else if (DECL_INITIAL (decl)) 5094 { 5095 error ("%Jcan%'t set %qE attribute after definition", decl, name); 5096 *no_add_attrs = true; 5097 } 5098 else 5099 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl) = 1; 5100 5101 return NULL_TREE; 5102} 5103 5104/* Handle a "malloc" attribute; arguments as in 5105 struct attribute_spec.handler. */ 5106 5107static tree 5108handle_malloc_attribute (tree *node, tree name, tree ARG_UNUSED (args), 5109 int ARG_UNUSED (flags), bool *no_add_attrs) 5110{ 5111 if (TREE_CODE (*node) == FUNCTION_DECL 5112 && POINTER_TYPE_P (TREE_TYPE (TREE_TYPE (*node)))) 5113 DECL_IS_MALLOC (*node) = 1; 5114 else 5115 { 5116 warning (OPT_Wattributes, "%qE attribute ignored", name); 5117 *no_add_attrs = true; 5118 } 5119 5120 return NULL_TREE; 5121} 5122 5123/* Handle a "returns_twice" attribute; arguments as in 5124 struct attribute_spec.handler. */ 5125 5126static tree 5127handle_returns_twice_attribute (tree *node, tree name, tree ARG_UNUSED (args), 5128 int ARG_UNUSED (flags), bool *no_add_attrs) 5129{ 5130 if (TREE_CODE (*node) == FUNCTION_DECL) 5131 DECL_IS_RETURNS_TWICE (*node) = 1; 5132 else 5133 { 5134 warning (OPT_Wattributes, "%qE attribute ignored", name); 5135 *no_add_attrs = true; 5136 } 5137 5138 return NULL_TREE; 5139} 5140 5141/* Handle a "no_limit_stack" attribute; arguments as in 5142 struct attribute_spec.handler. */ 5143 5144static tree 5145handle_no_limit_stack_attribute (tree *node, tree name, 5146 tree ARG_UNUSED (args), 5147 int ARG_UNUSED (flags), 5148 bool *no_add_attrs) 5149{ 5150 tree decl = *node; 5151 5152 if (TREE_CODE (decl) != FUNCTION_DECL) 5153 { 5154 error ("%J%qE attribute applies only to functions", decl, name); 5155 *no_add_attrs = true; 5156 } 5157 else if (DECL_INITIAL (decl)) 5158 { 5159 error ("%Jcan%'t set %qE attribute after definition", decl, name); 5160 *no_add_attrs = true; 5161 } 5162 else 5163 DECL_NO_LIMIT_STACK (decl) = 1; 5164 5165 return NULL_TREE; 5166} 5167 5168/* Handle a "pure" attribute; arguments as in 5169 struct attribute_spec.handler. */ 5170 5171static tree 5172handle_pure_attribute (tree *node, tree name, tree ARG_UNUSED (args), 5173 int ARG_UNUSED (flags), bool *no_add_attrs) 5174{ 5175 if (TREE_CODE (*node) == FUNCTION_DECL) 5176 DECL_IS_PURE (*node) = 1; 5177 /* ??? TODO: Support types. */ 5178 else 5179 { 5180 warning (OPT_Wattributes, "%qE attribute ignored", name); 5181 *no_add_attrs = true; 5182 } 5183 5184 return NULL_TREE; 5185} 5186 5187/* Handle a "no vops" attribute; arguments as in 5188 struct attribute_spec.handler. */ 5189 5190static tree 5191handle_novops_attribute (tree *node, tree ARG_UNUSED (name), 5192 tree ARG_UNUSED (args), int ARG_UNUSED (flags), 5193 bool *ARG_UNUSED (no_add_attrs)) 5194{ 5195 gcc_assert (TREE_CODE (*node) == FUNCTION_DECL); 5196 DECL_IS_NOVOPS (*node) = 1; 5197 return NULL_TREE; 5198} 5199 5200/* Handle a "deprecated" attribute; arguments as in 5201 struct attribute_spec.handler. */ 5202 5203static tree 5204handle_deprecated_attribute (tree *node, tree name, 5205 tree ARG_UNUSED (args), int flags, 5206 bool *no_add_attrs) 5207{ 5208 tree type = NULL_TREE; 5209 int warn = 0; 5210 tree what = NULL_TREE; 5211 5212 if (DECL_P (*node)) 5213 { 5214 tree decl = *node; 5215 type = TREE_TYPE (decl); 5216 5217 if (TREE_CODE (decl) == TYPE_DECL 5218 || TREE_CODE (decl) == PARM_DECL 5219 || TREE_CODE (decl) == VAR_DECL 5220 || TREE_CODE (decl) == FUNCTION_DECL 5221 || TREE_CODE (decl) == FIELD_DECL) 5222 TREE_DEPRECATED (decl) = 1; 5223 else 5224 warn = 1; 5225 } 5226 else if (TYPE_P (*node)) 5227 { 5228 if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE)) 5229 *node = build_variant_type_copy (*node); 5230 TREE_DEPRECATED (*node) = 1; 5231 type = *node; 5232 } 5233 else 5234 warn = 1; 5235 5236 if (warn) 5237 { 5238 *no_add_attrs = true; 5239 if (type && TYPE_NAME (type)) 5240 { 5241 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE) 5242 what = TYPE_NAME (*node); 5243 else if (TREE_CODE (TYPE_NAME (type)) == TYPE_DECL 5244 && DECL_NAME (TYPE_NAME (type))) 5245 what = DECL_NAME (TYPE_NAME (type)); 5246 } 5247 if (what) 5248 warning (OPT_Wattributes, "%qE attribute ignored for %qE", name, what); 5249 else 5250 warning (OPT_Wattributes, "%qE attribute ignored", name); 5251 } 5252 5253 return NULL_TREE; 5254} 5255 5256/* Handle a "vector_size" attribute; arguments as in 5257 struct attribute_spec.handler. */ 5258 5259static tree 5260handle_vector_size_attribute (tree *node, tree name, tree args, 5261 int ARG_UNUSED (flags), 5262 bool *no_add_attrs) 5263{ 5264 unsigned HOST_WIDE_INT vecsize, nunits; 5265 enum machine_mode orig_mode; 5266 tree type = *node, new_type, size; 5267 5268 *no_add_attrs = true; 5269 5270 size = TREE_VALUE (args); 5271 5272 if (!host_integerp (size, 1)) 5273 { 5274 warning (OPT_Wattributes, "%qE attribute ignored", name); 5275 return NULL_TREE; 5276 } 5277 5278 /* Get the vector size (in bytes). */ 5279 vecsize = tree_low_cst (size, 1); 5280 5281 /* We need to provide for vector pointers, vector arrays, and 5282 functions returning vectors. For example: 5283 5284 __attribute__((vector_size(16))) short *foo; 5285 5286 In this case, the mode is SI, but the type being modified is 5287 HI, so we need to look further. */ 5288 5289 while (POINTER_TYPE_P (type) 5290 || TREE_CODE (type) == FUNCTION_TYPE 5291 || TREE_CODE (type) == METHOD_TYPE 5292 || TREE_CODE (type) == ARRAY_TYPE) 5293 type = TREE_TYPE (type); 5294 5295 /* Get the mode of the type being modified. */ 5296 orig_mode = TYPE_MODE (type); 5297 5298 if (TREE_CODE (type) == RECORD_TYPE 5299 || TREE_CODE (type) == UNION_TYPE 5300 || TREE_CODE (type) == VECTOR_TYPE 5301 || (!SCALAR_FLOAT_MODE_P (orig_mode) 5302 && GET_MODE_CLASS (orig_mode) != MODE_INT) 5303 || !host_integerp (TYPE_SIZE_UNIT (type), 1)) 5304 { 5305 error ("invalid vector type for attribute %qE", name); 5306 return NULL_TREE; 5307 } 5308 5309 if (vecsize % tree_low_cst (TYPE_SIZE_UNIT (type), 1)) 5310 { 5311 error ("vector size not an integral multiple of component size"); 5312 return NULL; 5313 } 5314 5315 if (vecsize == 0) 5316 { 5317 error ("zero vector size"); 5318 return NULL; 5319 } 5320 5321 /* Calculate how many units fit in the vector. */ 5322 nunits = vecsize / tree_low_cst (TYPE_SIZE_UNIT (type), 1); 5323 if (nunits & (nunits - 1)) 5324 { 5325 error ("number of components of the vector not a power of two"); 5326 return NULL_TREE; 5327 } 5328 5329 new_type = build_vector_type (type, nunits); 5330 5331 /* Build back pointers if needed. */ 5332 *node = reconstruct_complex_type (*node, new_type); 5333 5334 return NULL_TREE; 5335} 5336 5337/* Handle the "nonnull" attribute. */ 5338static tree 5339handle_nonnull_attribute (tree *node, tree ARG_UNUSED (name), 5340 tree args, int ARG_UNUSED (flags), 5341 bool *no_add_attrs) 5342{ 5343 tree type = *node; 5344 unsigned HOST_WIDE_INT attr_arg_num; 5345 5346 /* If no arguments are specified, all pointer arguments should be 5347 non-null. Verify a full prototype is given so that the arguments 5348 will have the correct types when we actually check them later. */ 5349 if (!args) 5350 { 5351 if (!TYPE_ARG_TYPES (type)) 5352 { 5353 error ("nonnull attribute without arguments on a non-prototype"); 5354 *no_add_attrs = true; 5355 } 5356 return NULL_TREE; 5357 } 5358 5359 /* Argument list specified. Verify that each argument number references 5360 a pointer argument. */ 5361 for (attr_arg_num = 1; args; args = TREE_CHAIN (args)) 5362 { 5363 tree argument; 5364 unsigned HOST_WIDE_INT arg_num = 0, ck_num; 5365 5366 if (!get_nonnull_operand (TREE_VALUE (args), &arg_num)) 5367 { 5368 error ("nonnull argument has invalid operand number (argument %lu)", 5369 (unsigned long) attr_arg_num); 5370 *no_add_attrs = true; 5371 return NULL_TREE; 5372 } 5373 5374 argument = TYPE_ARG_TYPES (type); 5375 if (argument) 5376 { 5377 for (ck_num = 1; ; ck_num++) 5378 { 5379 if (!argument || ck_num == arg_num) 5380 break; 5381 argument = TREE_CHAIN (argument); 5382 } 5383 5384 if (!argument 5385 || TREE_CODE (TREE_VALUE (argument)) == VOID_TYPE) 5386 { 5387 error ("nonnull argument with out-of-range operand number (argument %lu, operand %lu)", 5388 (unsigned long) attr_arg_num, (unsigned long) arg_num); 5389 *no_add_attrs = true; 5390 return NULL_TREE; 5391 } 5392 5393 if (TREE_CODE (TREE_VALUE (argument)) != POINTER_TYPE) 5394 { 5395 error ("nonnull argument references non-pointer operand (argument %lu, operand %lu)", 5396 (unsigned long) attr_arg_num, (unsigned long) arg_num); 5397 *no_add_attrs = true; 5398 return NULL_TREE; 5399 } 5400 } 5401 } 5402 5403 return NULL_TREE; 5404} 5405 5406/* Check the argument list of a function call for null in argument slots 5407 that are marked as requiring a non-null pointer argument. */ 5408 5409static void 5410check_function_nonnull (tree attrs, tree params) 5411{ 5412 tree a, args, param; 5413 int param_num; 5414 5415 for (a = attrs; a; a = TREE_CHAIN (a)) 5416 { 5417 if (is_attribute_p ("nonnull", TREE_PURPOSE (a))) 5418 { 5419 args = TREE_VALUE (a); 5420 5421 /* Walk the argument list. If we encounter an argument number we 5422 should check for non-null, do it. If the attribute has no args, 5423 then every pointer argument is checked (in which case the check 5424 for pointer type is done in check_nonnull_arg). */ 5425 for (param = params, param_num = 1; ; 5426 param_num++, param = TREE_CHAIN (param)) 5427 { 5428 if (!param) 5429 break; 5430 if (!args || nonnull_check_p (args, param_num)) 5431 check_function_arguments_recurse (check_nonnull_arg, NULL, 5432 TREE_VALUE (param), 5433 param_num); 5434 } 5435 } 5436 } 5437} 5438 5439/* Check that the Nth argument of a function call (counting backwards 5440 from the end) is a (pointer)0. */ 5441 5442static void 5443check_function_sentinel (tree attrs, tree params, tree typelist) 5444{ 5445 tree attr = lookup_attribute ("sentinel", attrs); 5446 5447 if (attr) 5448 { 5449 /* Skip over the named arguments. */ 5450 while (typelist && params) 5451 { 5452 typelist = TREE_CHAIN (typelist); 5453 params = TREE_CHAIN (params); 5454 } 5455 5456 if (typelist || !params) 5457 warning (OPT_Wformat, 5458 "not enough variable arguments to fit a sentinel"); 5459 else 5460 { 5461 tree sentinel, end; 5462 unsigned pos = 0; 5463 5464 if (TREE_VALUE (attr)) 5465 { 5466 tree p = TREE_VALUE (TREE_VALUE (attr)); 5467 pos = TREE_INT_CST_LOW (p); 5468 } 5469 5470 sentinel = end = params; 5471 5472 /* Advance `end' ahead of `sentinel' by `pos' positions. */ 5473 while (pos > 0 && TREE_CHAIN (end)) 5474 { 5475 pos--; 5476 end = TREE_CHAIN (end); 5477 } 5478 if (pos > 0) 5479 { 5480 warning (OPT_Wformat, 5481 "not enough variable arguments to fit a sentinel"); 5482 return; 5483 } 5484 5485 /* Now advance both until we find the last parameter. */ 5486 while (TREE_CHAIN (end)) 5487 { 5488 end = TREE_CHAIN (end); 5489 sentinel = TREE_CHAIN (sentinel); 5490 } 5491 5492 /* Validate the sentinel. */ 5493 if ((!POINTER_TYPE_P (TREE_TYPE (TREE_VALUE (sentinel))) 5494 || !integer_zerop (TREE_VALUE (sentinel))) 5495 /* Although __null (in C++) is only an integer we allow it 5496 nevertheless, as we are guaranteed that it's exactly 5497 as wide as a pointer, and we don't want to force 5498 users to cast the NULL they have written there. 5499 We warn with -Wstrict-null-sentinel, though. */ 5500 && (warn_strict_null_sentinel 5501 || null_node != TREE_VALUE (sentinel))) 5502 warning (OPT_Wformat, "missing sentinel in function call"); 5503 } 5504 } 5505} 5506 5507/* Helper for check_function_nonnull; given a list of operands which 5508 must be non-null in ARGS, determine if operand PARAM_NUM should be 5509 checked. */ 5510 5511static bool 5512nonnull_check_p (tree args, unsigned HOST_WIDE_INT param_num) 5513{ 5514 unsigned HOST_WIDE_INT arg_num = 0; 5515 5516 for (; args; args = TREE_CHAIN (args)) 5517 { 5518 bool found = get_nonnull_operand (TREE_VALUE (args), &arg_num); 5519 5520 gcc_assert (found); 5521 5522 if (arg_num == param_num) 5523 return true; 5524 } 5525 return false; 5526} 5527 5528/* Check that the function argument PARAM (which is operand number 5529 PARAM_NUM) is non-null. This is called by check_function_nonnull 5530 via check_function_arguments_recurse. */ 5531 5532static void 5533check_nonnull_arg (void * ARG_UNUSED (ctx), tree param, 5534 unsigned HOST_WIDE_INT param_num) 5535{ 5536 /* Just skip checking the argument if it's not a pointer. This can 5537 happen if the "nonnull" attribute was given without an operand 5538 list (which means to check every pointer argument). */ 5539 5540 if (TREE_CODE (TREE_TYPE (param)) != POINTER_TYPE) 5541 return; 5542 5543 if (integer_zerop (param)) 5544 warning (OPT_Wnonnull, "null argument where non-null required " 5545 "(argument %lu)", (unsigned long) param_num); 5546} 5547 5548/* Helper for nonnull attribute handling; fetch the operand number 5549 from the attribute argument list. */ 5550 5551static bool 5552get_nonnull_operand (tree arg_num_expr, unsigned HOST_WIDE_INT *valp) 5553{ 5554 /* Verify the arg number is a constant. */ 5555 if (TREE_CODE (arg_num_expr) != INTEGER_CST 5556 || TREE_INT_CST_HIGH (arg_num_expr) != 0) 5557 return false; 5558 5559 *valp = TREE_INT_CST_LOW (arg_num_expr); 5560 return true; 5561} 5562 5563/* Handle a "nothrow" attribute; arguments as in 5564 struct attribute_spec.handler. */ 5565 5566static tree 5567handle_nothrow_attribute (tree *node, tree name, tree ARG_UNUSED (args), 5568 int ARG_UNUSED (flags), bool *no_add_attrs) 5569{ 5570 if (TREE_CODE (*node) == FUNCTION_DECL) 5571 TREE_NOTHROW (*node) = 1; 5572 /* ??? TODO: Support types. */ 5573 else 5574 { 5575 warning (OPT_Wattributes, "%qE attribute ignored", name); 5576 *no_add_attrs = true; 5577 } 5578 5579 return NULL_TREE; 5580} 5581 5582/* Handle a "cleanup" attribute; arguments as in 5583 struct attribute_spec.handler. */ 5584 5585static tree 5586handle_cleanup_attribute (tree *node, tree name, tree args, 5587 int ARG_UNUSED (flags), bool *no_add_attrs) 5588{ 5589 tree decl = *node; 5590 tree cleanup_id, cleanup_decl; 5591 5592 /* ??? Could perhaps support cleanups on TREE_STATIC, much like we do 5593 for global destructors in C++. This requires infrastructure that 5594 we don't have generically at the moment. It's also not a feature 5595 we'd be missing too much, since we do have attribute constructor. */ 5596 if (TREE_CODE (decl) != VAR_DECL || TREE_STATIC (decl)) 5597 { 5598 warning (OPT_Wattributes, "%qE attribute ignored", name); 5599 *no_add_attrs = true; 5600 return NULL_TREE; 5601 } 5602 5603 /* Verify that the argument is a function in scope. */ 5604 /* ??? We could support pointers to functions here as well, if 5605 that was considered desirable. */ 5606 cleanup_id = TREE_VALUE (args); 5607 if (TREE_CODE (cleanup_id) != IDENTIFIER_NODE) 5608 { 5609 error ("cleanup argument not an identifier"); 5610 *no_add_attrs = true; 5611 return NULL_TREE; 5612 } 5613 cleanup_decl = lookup_name (cleanup_id); 5614 if (!cleanup_decl || TREE_CODE (cleanup_decl) != FUNCTION_DECL) 5615 { 5616 error ("cleanup argument not a function"); 5617 *no_add_attrs = true; 5618 return NULL_TREE; 5619 } 5620 5621 /* That the function has proper type is checked with the 5622 eventual call to build_function_call. */ 5623 5624 return NULL_TREE; 5625} 5626 5627/* Handle a "warn_unused_result" attribute. No special handling. */ 5628 5629static tree 5630handle_warn_unused_result_attribute (tree *node, tree name, 5631 tree ARG_UNUSED (args), 5632 int ARG_UNUSED (flags), bool *no_add_attrs) 5633{ 5634 /* Ignore the attribute for functions not returning any value. */ 5635 if (VOID_TYPE_P (TREE_TYPE (*node))) 5636 { 5637 warning (OPT_Wattributes, "%qE attribute ignored", name); 5638 *no_add_attrs = true; 5639 } 5640 5641 return NULL_TREE; 5642} 5643 5644/* Handle a "sentinel" attribute. */ 5645 5646static tree 5647handle_sentinel_attribute (tree *node, tree name, tree args, 5648 int ARG_UNUSED (flags), bool *no_add_attrs) 5649{ 5650 tree params = TYPE_ARG_TYPES (*node); 5651 5652 if (!params) 5653 { 5654 warning (OPT_Wattributes, 5655 "%qE attribute requires prototypes with named arguments", name); 5656 *no_add_attrs = true; 5657 } 5658 else 5659 { 5660 while (TREE_CHAIN (params)) 5661 params = TREE_CHAIN (params); 5662 5663 if (VOID_TYPE_P (TREE_VALUE (params))) 5664 { 5665 warning (OPT_Wattributes, 5666 "%qE attribute only applies to variadic functions", name); 5667 *no_add_attrs = true; 5668 } 5669 } 5670 5671 if (args) 5672 { 5673 tree position = TREE_VALUE (args); 5674 5675 if (TREE_CODE (position) != INTEGER_CST) 5676 { 5677 warning (0, "requested position is not an integer constant"); 5678 *no_add_attrs = true; 5679 } 5680 else 5681 { 5682 if (tree_int_cst_lt (position, integer_zero_node)) 5683 { 5684 warning (0, "requested position is less than zero"); 5685 *no_add_attrs = true; 5686 } 5687 } 5688 } 5689 5690 return NULL_TREE; 5691} 5692 5693/* Check for valid arguments being passed to a function. */ 5694void 5695check_function_arguments (tree attrs, tree params, tree typelist) 5696{ 5697 /* Check for null being passed in a pointer argument that must be 5698 non-null. We also need to do this if format checking is enabled. */ 5699 5700 if (warn_nonnull) 5701 check_function_nonnull (attrs, params); 5702 5703 /* Check for errors in format strings. */ 5704 5705 if (warn_format || warn_missing_format_attribute) 5706 check_function_format (attrs, params); 5707 5708 if (warn_format) 5709 check_function_sentinel (attrs, params, typelist); 5710} 5711 5712/* Generic argument checking recursion routine. PARAM is the argument to 5713 be checked. PARAM_NUM is the number of the argument. CALLBACK is invoked 5714 once the argument is resolved. CTX is context for the callback. */ 5715void 5716check_function_arguments_recurse (void (*callback) 5717 (void *, tree, unsigned HOST_WIDE_INT), 5718 void *ctx, tree param, 5719 unsigned HOST_WIDE_INT param_num) 5720{ 5721 if ((TREE_CODE (param) == NOP_EXPR || TREE_CODE (param) == CONVERT_EXPR) 5722 && (TYPE_PRECISION (TREE_TYPE (param)) 5723 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (param, 0))))) 5724 { 5725 /* Strip coercion. */ 5726 check_function_arguments_recurse (callback, ctx, 5727 TREE_OPERAND (param, 0), param_num); 5728 return; 5729 } 5730 5731 if (TREE_CODE (param) == CALL_EXPR) 5732 { 5733 tree type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (param, 0))); 5734 tree attrs; 5735 bool found_format_arg = false; 5736 5737 /* See if this is a call to a known internationalization function 5738 that modifies a format arg. Such a function may have multiple 5739 format_arg attributes (for example, ngettext). */ 5740 5741 for (attrs = TYPE_ATTRIBUTES (type); 5742 attrs; 5743 attrs = TREE_CHAIN (attrs)) 5744 if (is_attribute_p ("format_arg", TREE_PURPOSE (attrs))) 5745 { 5746 tree inner_args; 5747 tree format_num_expr; 5748 int format_num; 5749 int i; 5750 5751 /* Extract the argument number, which was previously checked 5752 to be valid. */ 5753 format_num_expr = TREE_VALUE (TREE_VALUE (attrs)); 5754 5755 gcc_assert (TREE_CODE (format_num_expr) == INTEGER_CST 5756 && !TREE_INT_CST_HIGH (format_num_expr)); 5757 5758 format_num = TREE_INT_CST_LOW (format_num_expr); 5759 5760 for (inner_args = TREE_OPERAND (param, 1), i = 1; 5761 inner_args != 0; 5762 inner_args = TREE_CHAIN (inner_args), i++) 5763 if (i == format_num) 5764 { 5765 check_function_arguments_recurse (callback, ctx, 5766 TREE_VALUE (inner_args), 5767 param_num); 5768 found_format_arg = true; 5769 break; 5770 } 5771 } 5772 5773 /* If we found a format_arg attribute and did a recursive check, 5774 we are done with checking this argument. Otherwise, we continue 5775 and this will be considered a non-literal. */ 5776 if (found_format_arg) 5777 return; 5778 } 5779 5780 if (TREE_CODE (param) == COND_EXPR) 5781 { 5782 /* Check both halves of the conditional expression. */ 5783 check_function_arguments_recurse (callback, ctx, 5784 TREE_OPERAND (param, 1), param_num); 5785 check_function_arguments_recurse (callback, ctx, 5786 TREE_OPERAND (param, 2), param_num); 5787 return; 5788 } 5789 5790 (*callback) (ctx, param, param_num); 5791} 5792 5793/* Function to help qsort sort FIELD_DECLs by name order. */ 5794 5795int 5796field_decl_cmp (const void *x_p, const void *y_p) 5797{ 5798 const tree *const x = (const tree *const) x_p; 5799 const tree *const y = (const tree *const) y_p; 5800 5801 if (DECL_NAME (*x) == DECL_NAME (*y)) 5802 /* A nontype is "greater" than a type. */ 5803 return (TREE_CODE (*y) == TYPE_DECL) - (TREE_CODE (*x) == TYPE_DECL); 5804 if (DECL_NAME (*x) == NULL_TREE) 5805 return -1; 5806 if (DECL_NAME (*y) == NULL_TREE) 5807 return 1; 5808 if (DECL_NAME (*x) < DECL_NAME (*y)) 5809 return -1; 5810 return 1; 5811} 5812 5813static struct { 5814 gt_pointer_operator new_value; 5815 void *cookie; 5816} resort_data; 5817 5818/* This routine compares two fields like field_decl_cmp but using the 5819pointer operator in resort_data. */ 5820 5821static int 5822resort_field_decl_cmp (const void *x_p, const void *y_p) 5823{ 5824 const tree *const x = (const tree *const) x_p; 5825 const tree *const y = (const tree *const) y_p; 5826 5827 if (DECL_NAME (*x) == DECL_NAME (*y)) 5828 /* A nontype is "greater" than a type. */ 5829 return (TREE_CODE (*y) == TYPE_DECL) - (TREE_CODE (*x) == TYPE_DECL); 5830 if (DECL_NAME (*x) == NULL_TREE) 5831 return -1; 5832 if (DECL_NAME (*y) == NULL_TREE) 5833 return 1; 5834 { 5835 tree d1 = DECL_NAME (*x); 5836 tree d2 = DECL_NAME (*y); 5837 resort_data.new_value (&d1, resort_data.cookie); 5838 resort_data.new_value (&d2, resort_data.cookie); 5839 if (d1 < d2) 5840 return -1; 5841 } 5842 return 1; 5843} 5844 5845/* Resort DECL_SORTED_FIELDS because pointers have been reordered. */ 5846 5847void 5848resort_sorted_fields (void *obj, 5849 void * ARG_UNUSED (orig_obj), 5850 gt_pointer_operator new_value, 5851 void *cookie) 5852{ 5853 struct sorted_fields_type *sf = (struct sorted_fields_type *) obj; 5854 resort_data.new_value = new_value; 5855 resort_data.cookie = cookie; 5856 qsort (&sf->elts[0], sf->len, sizeof (tree), 5857 resort_field_decl_cmp); 5858} 5859 5860/* Subroutine of c_parse_error. 5861 Return the result of concatenating LHS and RHS. RHS is really 5862 a string literal, its first character is indicated by RHS_START and 5863 RHS_SIZE is its length (including the terminating NUL character). 5864 5865 The caller is responsible for deleting the returned pointer. */ 5866 5867static char * 5868catenate_strings (const char *lhs, const char *rhs_start, int rhs_size) 5869{ 5870 const int lhs_size = strlen (lhs); 5871 char *result = XNEWVEC (char, lhs_size + rhs_size); 5872 strncpy (result, lhs, lhs_size); 5873 strncpy (result + lhs_size, rhs_start, rhs_size); 5874 return result; 5875} 5876 5877/* Issue the error given by GMSGID, indicating that it occurred before 5878 TOKEN, which had the associated VALUE. */ 5879 5880void 5881c_parse_error (const char *gmsgid, enum cpp_ttype token, tree value) 5882{ 5883#define catenate_messages(M1, M2) catenate_strings ((M1), (M2), sizeof (M2)) 5884 5885 char *message = NULL; 5886 5887 if (token == CPP_EOF) 5888 message = catenate_messages (gmsgid, " at end of input"); 5889 else if (token == CPP_CHAR || token == CPP_WCHAR) 5890 { 5891 unsigned int val = TREE_INT_CST_LOW (value); 5892 const char *const ell = (token == CPP_CHAR) ? "" : "L"; 5893 if (val <= UCHAR_MAX && ISGRAPH (val)) 5894 message = catenate_messages (gmsgid, " before %s'%c'"); 5895 else 5896 message = catenate_messages (gmsgid, " before %s'\\x%x'"); 5897 5898 error (message, ell, val); 5899 free (message); 5900 message = NULL; 5901 } 5902 else if (token == CPP_STRING || token == CPP_WSTRING) 5903 message = catenate_messages (gmsgid, " before string constant"); 5904 else if (token == CPP_NUMBER) 5905 message = catenate_messages (gmsgid, " before numeric constant"); 5906 else if (token == CPP_NAME) 5907 { 5908 message = catenate_messages (gmsgid, " before %qE"); 5909 error (message, value); 5910 free (message); 5911 message = NULL; 5912 } 5913 else if (token == CPP_PRAGMA) 5914 message = catenate_messages (gmsgid, " before %<#pragma%>"); 5915 else if (token == CPP_PRAGMA_EOL) 5916 message = catenate_messages (gmsgid, " before end of line"); 5917 else if (token < N_TTYPES) 5918 { 5919 message = catenate_messages (gmsgid, " before %qs token"); 5920 error (message, cpp_type2name (token)); 5921 free (message); 5922 message = NULL; 5923 } 5924 else 5925 error (gmsgid); 5926 5927 if (message) 5928 { 5929 error (message); 5930 free (message); 5931 } 5932#undef catenate_messages 5933} 5934 5935/* Walk a gimplified function and warn for functions whose return value is 5936 ignored and attribute((warn_unused_result)) is set. This is done before 5937 inlining, so we don't have to worry about that. */ 5938 5939void 5940c_warn_unused_result (tree *top_p) 5941{ 5942 tree t = *top_p; 5943 tree_stmt_iterator i; 5944 tree fdecl, ftype; 5945 5946 switch (TREE_CODE (t)) 5947 { 5948 case STATEMENT_LIST: 5949 for (i = tsi_start (*top_p); !tsi_end_p (i); tsi_next (&i)) 5950 c_warn_unused_result (tsi_stmt_ptr (i)); 5951 break; 5952 5953 case COND_EXPR: 5954 c_warn_unused_result (&COND_EXPR_THEN (t)); 5955 c_warn_unused_result (&COND_EXPR_ELSE (t)); 5956 break; 5957 case BIND_EXPR: 5958 c_warn_unused_result (&BIND_EXPR_BODY (t)); 5959 break; 5960 case TRY_FINALLY_EXPR: 5961 case TRY_CATCH_EXPR: 5962 c_warn_unused_result (&TREE_OPERAND (t, 0)); 5963 c_warn_unused_result (&TREE_OPERAND (t, 1)); 5964 break; 5965 case CATCH_EXPR: 5966 c_warn_unused_result (&CATCH_BODY (t)); 5967 break; 5968 case EH_FILTER_EXPR: 5969 c_warn_unused_result (&EH_FILTER_FAILURE (t)); 5970 break; 5971 5972 case CALL_EXPR: 5973 if (TREE_USED (t)) 5974 break; 5975 5976 /* This is a naked call, as opposed to a CALL_EXPR nested inside 5977 a MODIFY_EXPR. All calls whose value is ignored should be 5978 represented like this. Look for the attribute. */ 5979 fdecl = get_callee_fndecl (t); 5980 if (fdecl) 5981 ftype = TREE_TYPE (fdecl); 5982 else 5983 { 5984 ftype = TREE_TYPE (TREE_OPERAND (t, 0)); 5985 /* Look past pointer-to-function to the function type itself. */ 5986 ftype = TREE_TYPE (ftype); 5987 } 5988 5989 if (lookup_attribute ("warn_unused_result", TYPE_ATTRIBUTES (ftype))) 5990 { 5991 if (fdecl) 5992 warning (0, "%Hignoring return value of %qD, " 5993 "declared with attribute warn_unused_result", 5994 EXPR_LOCUS (t), fdecl); 5995 else 5996 warning (0, "%Hignoring return value of function " 5997 "declared with attribute warn_unused_result", 5998 EXPR_LOCUS (t)); 5999 } 6000 break; 6001 6002 default: 6003 /* Not a container, not a call, or a call whose value is used. */ 6004 break; 6005 } 6006} 6007 6008/* Convert a character from the host to the target execution character 6009 set. cpplib handles this, mostly. */ 6010 6011HOST_WIDE_INT 6012c_common_to_target_charset (HOST_WIDE_INT c) 6013{ 6014 /* Character constants in GCC proper are sign-extended under -fsigned-char, 6015 zero-extended under -fno-signed-char. cpplib insists that characters 6016 and character constants are always unsigned. Hence we must convert 6017 back and forth. */ 6018 cppchar_t uc = ((cppchar_t)c) & ((((cppchar_t)1) << CHAR_BIT)-1); 6019 6020 uc = cpp_host_to_exec_charset (parse_in, uc); 6021 6022 if (flag_signed_char) 6023 return ((HOST_WIDE_INT)uc) << (HOST_BITS_PER_WIDE_INT - CHAR_TYPE_SIZE) 6024 >> (HOST_BITS_PER_WIDE_INT - CHAR_TYPE_SIZE); 6025 else 6026 return uc; 6027} 6028 6029/* Build the result of __builtin_offsetof. EXPR is a nested sequence of 6030 component references, with STOP_REF, or alternatively an INDIRECT_REF of 6031 NULL, at the bottom; much like the traditional rendering of offsetof as a 6032 macro. Returns the folded and properly cast result. */ 6033 6034static tree 6035fold_offsetof_1 (tree expr, tree stop_ref) 6036{ 6037 enum tree_code code = PLUS_EXPR; 6038 tree base, off, t; 6039 6040 if (expr == stop_ref && TREE_CODE (expr) != ERROR_MARK) 6041 return size_zero_node; 6042 6043 switch (TREE_CODE (expr)) 6044 { 6045 case ERROR_MARK: 6046 return expr; 6047 6048 case VAR_DECL: 6049 error ("cannot apply %<offsetof%> to static data member %qD", expr); 6050 return error_mark_node; 6051 6052 case CALL_EXPR: 6053 error ("cannot apply %<offsetof%> when %<operator[]%> is overloaded"); 6054 return error_mark_node; 6055 6056 case INTEGER_CST: 6057 gcc_assert (integer_zerop (expr)); 6058 return size_zero_node; 6059 6060 case NOP_EXPR: 6061 case INDIRECT_REF: 6062 base = fold_offsetof_1 (TREE_OPERAND (expr, 0), stop_ref); 6063 gcc_assert (base == error_mark_node || base == size_zero_node); 6064 return base; 6065 6066 case COMPONENT_REF: 6067 base = fold_offsetof_1 (TREE_OPERAND (expr, 0), stop_ref); 6068 if (base == error_mark_node) 6069 return base; 6070 6071 t = TREE_OPERAND (expr, 1); 6072 if (DECL_C_BIT_FIELD (t)) 6073 { 6074 error ("attempt to take address of bit-field structure " 6075 "member %qD", t); 6076 return error_mark_node; 6077 } 6078 off = size_binop (PLUS_EXPR, DECL_FIELD_OFFSET (t), 6079 size_int (tree_low_cst (DECL_FIELD_BIT_OFFSET (t), 1) 6080 / BITS_PER_UNIT)); 6081 break; 6082 6083 case ARRAY_REF: 6084 base = fold_offsetof_1 (TREE_OPERAND (expr, 0), stop_ref); 6085 if (base == error_mark_node) 6086 return base; 6087 6088 t = TREE_OPERAND (expr, 1); 6089 if (TREE_CODE (t) == INTEGER_CST && tree_int_cst_sgn (t) < 0) 6090 { 6091 code = MINUS_EXPR; 6092 t = fold_build1 (NEGATE_EXPR, TREE_TYPE (t), t); 6093 } 6094 t = convert (sizetype, t); 6095 off = size_binop (MULT_EXPR, TYPE_SIZE_UNIT (TREE_TYPE (expr)), t); 6096 break; 6097 6098 case COMPOUND_EXPR: 6099 /* Handle static members of volatile structs. */ 6100 t = TREE_OPERAND (expr, 1); 6101 gcc_assert (TREE_CODE (t) == VAR_DECL); 6102 return fold_offsetof_1 (t, stop_ref); 6103 6104 default: 6105 gcc_unreachable (); 6106 } 6107 6108 return size_binop (code, base, off); 6109} 6110 6111tree 6112fold_offsetof (tree expr, tree stop_ref) 6113{ 6114 /* Convert back from the internal sizetype to size_t. */ 6115 return convert (size_type_node, fold_offsetof_1 (expr, stop_ref)); 6116} 6117 6118/* Print an error message for an invalid lvalue. USE says 6119 how the lvalue is being used and so selects the error message. */ 6120 6121void 6122lvalue_error (enum lvalue_use use) 6123{ 6124 switch (use) 6125 { 6126 case lv_assign: 6127 error ("lvalue required as left operand of assignment"); 6128 break; 6129 case lv_increment: 6130 error ("lvalue required as increment operand"); 6131 break; 6132 case lv_decrement: 6133 error ("lvalue required as decrement operand"); 6134 break; 6135 case lv_addressof: 6136 error ("lvalue required as unary %<&%> operand"); 6137 break; 6138 case lv_asm: 6139 error ("lvalue required in asm statement"); 6140 break; 6141 default: 6142 gcc_unreachable (); 6143 } 6144} 6145 6146/* *PTYPE is an incomplete array. Complete it with a domain based on 6147 INITIAL_VALUE. If INITIAL_VALUE is not present, use 1 if DO_DEFAULT 6148 is true. Return 0 if successful, 1 if INITIAL_VALUE can't be deciphered, 6149 2 if INITIAL_VALUE was NULL, and 3 if INITIAL_VALUE was empty. */ 6150 6151int 6152complete_array_type (tree *ptype, tree initial_value, bool do_default) 6153{ 6154 tree maxindex, type, main_type, elt, unqual_elt; 6155 int failure = 0, quals; 6156 6157 maxindex = size_zero_node; 6158 if (initial_value) 6159 { 6160 if (TREE_CODE (initial_value) == STRING_CST) 6161 { 6162 int eltsize 6163 = int_size_in_bytes (TREE_TYPE (TREE_TYPE (initial_value))); 6164 maxindex = size_int (TREE_STRING_LENGTH (initial_value)/eltsize - 1); 6165 } 6166 else if (TREE_CODE (initial_value) == CONSTRUCTOR) 6167 { 6168 VEC(constructor_elt,gc) *v = CONSTRUCTOR_ELTS (initial_value); 6169 6170 if (VEC_empty (constructor_elt, v)) 6171 { 6172 if (pedantic) 6173 failure = 3; 6174 maxindex = integer_minus_one_node; 6175 } 6176 else 6177 { 6178 tree curindex; 6179 unsigned HOST_WIDE_INT cnt; 6180 constructor_elt *ce; 6181 6182 if (VEC_index (constructor_elt, v, 0)->index) 6183 maxindex = fold_convert (sizetype, 6184 VEC_index (constructor_elt, 6185 v, 0)->index); 6186 curindex = maxindex; 6187 6188 for (cnt = 1; 6189 VEC_iterate (constructor_elt, v, cnt, ce); 6190 cnt++) 6191 { 6192 if (ce->index) 6193 curindex = fold_convert (sizetype, ce->index); 6194 else 6195 curindex = size_binop (PLUS_EXPR, curindex, size_one_node); 6196 6197 if (tree_int_cst_lt (maxindex, curindex)) 6198 maxindex = curindex; 6199 } 6200 } 6201 } 6202 else 6203 { 6204 /* Make an error message unless that happened already. */ 6205 if (initial_value != error_mark_node) 6206 failure = 1; 6207 } 6208 } 6209 else 6210 { 6211 failure = 2; 6212 if (!do_default) 6213 return failure; 6214 } 6215 6216 type = *ptype; 6217 elt = TREE_TYPE (type); 6218 quals = TYPE_QUALS (strip_array_types (elt)); 6219 if (quals == 0) 6220 unqual_elt = elt; 6221 else 6222 unqual_elt = c_build_qualified_type (elt, TYPE_UNQUALIFIED); 6223 6224 /* Using build_distinct_type_copy and modifying things afterward instead 6225 of using build_array_type to create a new type preserves all of the 6226 TYPE_LANG_FLAG_? bits that the front end may have set. */ 6227 main_type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type)); 6228 TREE_TYPE (main_type) = unqual_elt; 6229 TYPE_DOMAIN (main_type) = build_index_type (maxindex); 6230 layout_type (main_type); 6231 6232 if (quals == 0) 6233 type = main_type; 6234 else 6235 type = c_build_qualified_type (main_type, quals); 6236 6237 *ptype = type; 6238 return failure; 6239} 6240 6241 6242/* Used to help initialize the builtin-types.def table. When a type of 6243 the correct size doesn't exist, use error_mark_node instead of NULL. 6244 The later results in segfaults even when a decl using the type doesn't 6245 get invoked. */ 6246 6247tree 6248builtin_type_for_size (int size, bool unsignedp) 6249{ 6250 tree type = lang_hooks.types.type_for_size (size, unsignedp); 6251 return type ? type : error_mark_node; 6252} 6253 6254/* A helper function for resolve_overloaded_builtin in resolving the 6255 overloaded __sync_ builtins. Returns a positive power of 2 if the 6256 first operand of PARAMS is a pointer to a supported data type. 6257 Returns 0 if an error is encountered. */ 6258 6259static int 6260sync_resolve_size (tree function, tree params) 6261{ 6262 tree type; 6263 int size; 6264 6265 if (params == NULL) 6266 { 6267 error ("too few arguments to function %qE", function); 6268 return 0; 6269 } 6270 6271 type = TREE_TYPE (TREE_VALUE (params)); 6272 if (TREE_CODE (type) != POINTER_TYPE) 6273 goto incompatible; 6274 6275 type = TREE_TYPE (type); 6276 if (!INTEGRAL_TYPE_P (type) && !POINTER_TYPE_P (type)) 6277 goto incompatible; 6278 6279 size = tree_low_cst (TYPE_SIZE_UNIT (type), 1); 6280 if (size == 1 || size == 2 || size == 4 || size == 8 || size == 16) 6281 return size; 6282 6283 incompatible: 6284 error ("incompatible type for argument %d of %qE", 1, function); 6285 return 0; 6286} 6287 6288/* A helper function for resolve_overloaded_builtin. Adds casts to 6289 PARAMS to make arguments match up with those of FUNCTION. Drops 6290 the variadic arguments at the end. Returns false if some error 6291 was encountered; true on success. */ 6292 6293static bool 6294sync_resolve_params (tree orig_function, tree function, tree params) 6295{ 6296 tree arg_types = TYPE_ARG_TYPES (TREE_TYPE (function)); 6297 tree ptype; 6298 int number; 6299 6300 /* We've declared the implementation functions to use "volatile void *" 6301 as the pointer parameter, so we shouldn't get any complaints from the 6302 call to check_function_arguments what ever type the user used. */ 6303 arg_types = TREE_CHAIN (arg_types); 6304 ptype = TREE_TYPE (TREE_TYPE (TREE_VALUE (params))); 6305 number = 2; 6306 6307 /* For the rest of the values, we need to cast these to FTYPE, so that we 6308 don't get warnings for passing pointer types, etc. */ 6309 while (arg_types != void_list_node) 6310 { 6311 tree val; 6312 6313 params = TREE_CHAIN (params); 6314 if (params == NULL) 6315 { 6316 error ("too few arguments to function %qE", orig_function); 6317 return false; 6318 } 6319 6320 /* ??? Ideally for the first conversion we'd use convert_for_assignment 6321 so that we get warnings for anything that doesn't match the pointer 6322 type. This isn't portable across the C and C++ front ends atm. */ 6323 val = TREE_VALUE (params); 6324 val = convert (ptype, val); 6325 val = convert (TREE_VALUE (arg_types), val); 6326 TREE_VALUE (params) = val; 6327 6328 arg_types = TREE_CHAIN (arg_types); 6329 number++; 6330 } 6331 6332 /* The definition of these primitives is variadic, with the remaining 6333 being "an optional list of variables protected by the memory barrier". 6334 No clue what that's supposed to mean, precisely, but we consider all 6335 call-clobbered variables to be protected so we're safe. */ 6336 TREE_CHAIN (params) = NULL; 6337 6338 return true; 6339} 6340 6341/* A helper function for resolve_overloaded_builtin. Adds a cast to 6342 RESULT to make it match the type of the first pointer argument in 6343 PARAMS. */ 6344 6345static tree 6346sync_resolve_return (tree params, tree result) 6347{ 6348 tree ptype = TREE_TYPE (TREE_TYPE (TREE_VALUE (params))); 6349 ptype = TYPE_MAIN_VARIANT (ptype); 6350 return convert (ptype, result); 6351} 6352 6353/* Some builtin functions are placeholders for other expressions. This 6354 function should be called immediately after parsing the call expression 6355 before surrounding code has committed to the type of the expression. 6356 6357 FUNCTION is the DECL that has been invoked; it is known to be a builtin. 6358 PARAMS is the argument list for the call. The return value is non-null 6359 when expansion is complete, and null if normal processing should 6360 continue. */ 6361 6362tree 6363resolve_overloaded_builtin (tree function, tree params) 6364{ 6365 enum built_in_function orig_code = DECL_FUNCTION_CODE (function); 6366 switch (DECL_BUILT_IN_CLASS (function)) 6367 { 6368 case BUILT_IN_NORMAL: 6369 break; 6370 case BUILT_IN_MD: 6371 if (targetm.resolve_overloaded_builtin) 6372 return targetm.resolve_overloaded_builtin (function, params); 6373 else 6374 return NULL_TREE; 6375 default: 6376 return NULL_TREE; 6377 } 6378 6379 /* Handle BUILT_IN_NORMAL here. */ 6380 switch (orig_code) 6381 { 6382 case BUILT_IN_FETCH_AND_ADD_N: 6383 case BUILT_IN_FETCH_AND_SUB_N: 6384 case BUILT_IN_FETCH_AND_OR_N: 6385 case BUILT_IN_FETCH_AND_AND_N: 6386 case BUILT_IN_FETCH_AND_XOR_N: 6387 case BUILT_IN_FETCH_AND_NAND_N: 6388 case BUILT_IN_ADD_AND_FETCH_N: 6389 case BUILT_IN_SUB_AND_FETCH_N: 6390 case BUILT_IN_OR_AND_FETCH_N: 6391 case BUILT_IN_AND_AND_FETCH_N: 6392 case BUILT_IN_XOR_AND_FETCH_N: 6393 case BUILT_IN_NAND_AND_FETCH_N: 6394 case BUILT_IN_BOOL_COMPARE_AND_SWAP_N: 6395 case BUILT_IN_VAL_COMPARE_AND_SWAP_N: 6396 case BUILT_IN_LOCK_TEST_AND_SET_N: 6397 case BUILT_IN_LOCK_RELEASE_N: 6398 { 6399 int n = sync_resolve_size (function, params); 6400 tree new_function, result; 6401 6402 if (n == 0) 6403 return error_mark_node; 6404 6405 new_function = built_in_decls[orig_code + exact_log2 (n) + 1]; 6406 if (!sync_resolve_params (function, new_function, params)) 6407 return error_mark_node; 6408 6409 result = build_function_call (new_function, params); 6410 if (orig_code != BUILT_IN_BOOL_COMPARE_AND_SWAP_N 6411 && orig_code != BUILT_IN_LOCK_RELEASE_N) 6412 result = sync_resolve_return (params, result); 6413 6414 return result; 6415 } 6416 6417 default: 6418 return NULL_TREE; 6419 } 6420} 6421 6422/* Ignoring their sign, return true if two scalar types are the same. */ 6423bool 6424same_scalar_type_ignoring_signedness (tree t1, tree t2) 6425{ 6426 enum tree_code c1 = TREE_CODE (t1), c2 = TREE_CODE (t2); 6427 6428 gcc_assert ((c1 == INTEGER_TYPE || c1 == REAL_TYPE) 6429 && (c2 == INTEGER_TYPE || c2 == REAL_TYPE)); 6430 6431 /* Equality works here because c_common_signed_type uses 6432 TYPE_MAIN_VARIANT. */ 6433 return lang_hooks.types.signed_type (t1) 6434 == lang_hooks.types.signed_type (t2); 6435} 6436 6437/* Check for missing format attributes on function pointers. LTYPE is 6438 the new type or left-hand side type. RTYPE is the old type or 6439 right-hand side type. Returns TRUE if LTYPE is missing the desired 6440 attribute. */ 6441 6442bool 6443check_missing_format_attribute (tree ltype, tree rtype) 6444{ 6445 tree const ttr = TREE_TYPE (rtype), ttl = TREE_TYPE (ltype); 6446 tree ra; 6447 6448 for (ra = TYPE_ATTRIBUTES (ttr); ra; ra = TREE_CHAIN (ra)) 6449 if (is_attribute_p ("format", TREE_PURPOSE (ra))) 6450 break; 6451 if (ra) 6452 { 6453 tree la; 6454 for (la = TYPE_ATTRIBUTES (ttl); la; la = TREE_CHAIN (la)) 6455 if (is_attribute_p ("format", TREE_PURPOSE (la))) 6456 break; 6457 return !la; 6458 } 6459 else 6460 return false; 6461} 6462 6463/* Subscripting with type char is likely to lose on a machine where 6464 chars are signed. So warn on any machine, but optionally. Don't 6465 warn for unsigned char since that type is safe. Don't warn for 6466 signed char because anyone who uses that must have done so 6467 deliberately. Furthermore, we reduce the false positive load by 6468 warning only for non-constant value of type char. */ 6469 6470void 6471warn_array_subscript_with_type_char (tree index) 6472{ 6473 if (TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node 6474 && TREE_CODE (index) != INTEGER_CST) 6475 warning (OPT_Wchar_subscripts, "array subscript has type %<char%>"); 6476} 6477 6478/* Implement -Wparentheses for the unexpected C precedence rules, to 6479 cover cases like x + y << z which readers are likely to 6480 misinterpret. We have seen an expression in which CODE is a binary 6481 operator used to combine expressions headed by CODE_LEFT and 6482 CODE_RIGHT. CODE_LEFT and CODE_RIGHT may be ERROR_MARK, which 6483 means that that side of the expression was not formed using a 6484 binary operator, or it was enclosed in parentheses. */ 6485 6486void 6487warn_about_parentheses (enum tree_code code, enum tree_code code_left, 6488 enum tree_code code_right) 6489{ 6490 if (!warn_parentheses) 6491 return; 6492 6493 if (code == LSHIFT_EXPR || code == RSHIFT_EXPR) 6494 { 6495 if (code_left == PLUS_EXPR || code_left == MINUS_EXPR 6496 || code_right == PLUS_EXPR || code_right == MINUS_EXPR) 6497 warning (OPT_Wparentheses, 6498 "suggest parentheses around + or - inside shift"); 6499 } 6500 6501 if (code == TRUTH_ORIF_EXPR) 6502 { 6503 if (code_left == TRUTH_ANDIF_EXPR 6504 || code_right == TRUTH_ANDIF_EXPR) 6505 warning (OPT_Wparentheses, 6506 "suggest parentheses around && within ||"); 6507 } 6508 6509 if (code == BIT_IOR_EXPR) 6510 { 6511 if (code_left == BIT_AND_EXPR || code_left == BIT_XOR_EXPR 6512 || code_left == PLUS_EXPR || code_left == MINUS_EXPR 6513 || code_right == BIT_AND_EXPR || code_right == BIT_XOR_EXPR 6514 || code_right == PLUS_EXPR || code_right == MINUS_EXPR) 6515 warning (OPT_Wparentheses, 6516 "suggest parentheses around arithmetic in operand of |"); 6517 /* Check cases like x|y==z */ 6518 if (TREE_CODE_CLASS (code_left) == tcc_comparison 6519 || TREE_CODE_CLASS (code_right) == tcc_comparison) 6520 warning (OPT_Wparentheses, 6521 "suggest parentheses around comparison in operand of |"); 6522 } 6523 6524 if (code == BIT_XOR_EXPR) 6525 { 6526 if (code_left == BIT_AND_EXPR 6527 || code_left == PLUS_EXPR || code_left == MINUS_EXPR 6528 || code_right == BIT_AND_EXPR 6529 || code_right == PLUS_EXPR || code_right == MINUS_EXPR) 6530 warning (OPT_Wparentheses, 6531 "suggest parentheses around arithmetic in operand of ^"); 6532 /* Check cases like x^y==z */ 6533 if (TREE_CODE_CLASS (code_left) == tcc_comparison 6534 || TREE_CODE_CLASS (code_right) == tcc_comparison) 6535 warning (OPT_Wparentheses, 6536 "suggest parentheses around comparison in operand of ^"); 6537 } 6538 6539 if (code == BIT_AND_EXPR) 6540 { 6541 if (code_left == PLUS_EXPR || code_left == MINUS_EXPR 6542 || code_right == PLUS_EXPR || code_right == MINUS_EXPR) 6543 warning (OPT_Wparentheses, 6544 "suggest parentheses around + or - in operand of &"); 6545 /* Check cases like x&y==z */ 6546 if (TREE_CODE_CLASS (code_left) == tcc_comparison 6547 || TREE_CODE_CLASS (code_right) == tcc_comparison) 6548 warning (OPT_Wparentheses, 6549 "suggest parentheses around comparison in operand of &"); 6550 } 6551 6552 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */ 6553 if (TREE_CODE_CLASS (code) == tcc_comparison 6554 && (TREE_CODE_CLASS (code_left) == tcc_comparison 6555 || TREE_CODE_CLASS (code_right) == tcc_comparison)) 6556 warning (OPT_Wparentheses, "comparisons like X<=Y<=Z do not " 6557 "have their mathematical meaning"); 6558} 6559 6560 6561#include "gt-c-common.h" 6562