1; Options for the language- and target-independent parts of the compiler.
2
3; Copyright (C) 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
4;
5; This file is part of GCC.
6;
7; GCC is free software; you can redistribute it and/or modify it under
8; the terms of the GNU General Public License as published by the Free
9; Software Foundation; either version 2, or (at your option) any later
10; version.
11;
12; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13; WARRANTY; without even the implied warranty of MERCHANTABILITY or
14; FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15; for more details.
16;
17; You should have received a copy of the GNU General Public License
18; along with GCC; see the file COPYING.  If not, write to the Free
19; Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
20; 02110-1301, USA.
21
22; See the GCC internals manual for a description of this file's format.
23
24; Please try to keep this file in ASCII collating order.
25
26-help
27Common
28Display this information
29
30-param
31Common Separate
32--param <param>=<value>	Set parameter <param> to value.  See below for a complete list of parameters
33
34-target-help
35Common
36
37-version
38Common
39
40G
41Common Joined Separate UInteger
42-G<number>	Put global and static data smaller than <number> bytes into a special section (on some targets)
43
44O
45Common JoinedOrMissing
46-O<number>	Set optimization level to <number>
47
48Os
49Common
50Optimize for space rather than speed
51
52W
53Common RejectNegative
54This switch is deprecated; use -Wextra instead
55
56Waggregate-return
57Common Var(warn_aggregate_return)
58Warn about returning structures, unions or arrays
59
60Wattributes
61Common Var(warn_attributes) Init(1)
62Warn about inappropriate attribute usage
63
64Wcast-align
65Common Var(warn_cast_align)
66Warn about pointer casts which increase alignment
67
68Wdeprecated-declarations
69Common Var(warn_deprecated_decl) Init(1)
70Warn about uses of __attribute__((deprecated)) declarations
71
72Wdisabled-optimization
73Common Var(warn_disabled_optimization)
74Warn when an optimization pass is disabled
75
76Werror
77Common Var(warnings_are_errors)
78Treat all warnings as errors
79
80Werror=
81Common Joined
82Treat specified warning as error
83
84Wextra
85Common
86Print extra (possibly unwanted) warnings
87
88Wfatal-errors
89Common Var(flag_fatal_errors)
90Exit on the first error occurred
91
92Winline
93Common Var(warn_inline)
94Warn when an inlined function cannot be inlined
95
96Wlarger-than-
97Common RejectNegative Joined UInteger
98-Wlarger-than-<number> Warn if an object is larger than <number> bytes
99
100Wframe-larger-than-
101Common RejectNegative Joined UInteger
102-Wframe-larger-than-<number> Warn if the frame size of a function is larger than <number> bytes
103
104Wunsafe-loop-optimizations
105Common Var(warn_unsafe_loop_optimizations)
106Warn if the loop cannot be optimized due to nontrivial assumptions.
107
108Wmissing-noreturn
109Common Var(warn_missing_noreturn)
110Warn about functions which might be candidates for __attribute__((noreturn))
111
112Woverflow
113Common Var(warn_overflow) Init(1)
114Warn about overflow in arithmetic expressions
115
116Wpacked
117Common Var(warn_packed)
118Warn when the packed attribute has no effect on struct layout
119
120Wpadded
121Common Var(warn_padded)
122Warn when padding is required to align structure members
123
124Wshadow
125Common Var(warn_shadow)
126Warn when one local variable shadows another
127
128Wstack-protector
129Common Var(warn_stack_protect)
130Warn when not issuing stack smashing protection for some reason
131
132Wstrict-aliasing
133Common
134Warn about code which might break strict aliasing rules
135
136Wstrict-aliasing=
137Common Joined UInteger
138Warn about code which might break strict aliasing rules
139
140Wstrict-overflow
141Common
142Warn about optimizations that assume that signed overflow is undefined
143
144Wstrict-overflow=
145Common Joined UInteger
146Warn about optimizations that assume that signed overflow is undefined
147
148Wswitch
149Common Var(warn_switch)
150Warn about enumerated switches, with no default, missing a case
151
152Wswitch-default
153Common Var(warn_switch_default)
154Warn about enumerated switches missing a \"default:\" statement
155
156Wswitch-enum
157Common Var(warn_switch_enum)
158Warn about all enumerated switches missing a specific case
159
160Wsystem-headers
161Common Var(warn_system_headers)
162Do not suppress warnings from system headers
163
164Wuninitialized
165Common Var(warn_uninitialized)
166Warn about uninitialized automatic variables
167
168Wunreachable-code
169Common Var(warn_notreached)
170Warn about code that will never be executed
171
172Wunused
173Common
174Enable all -Wunused- warnings
175
176Wunused-function
177Common Var(warn_unused_function)
178Warn when a function is unused
179
180Wunused-label
181Common Var(warn_unused_label)
182Warn when a label is unused
183
184Wunused-parameter
185Common Var(warn_unused_parameter)
186Warn when a function parameter is unused
187
188Wunused-value
189Common Var(warn_unused_value)
190Warn when an expression value is unused
191
192Wunused-variable
193Common Var(warn_unused_variable)
194Warn when a variable is unused
195
196Wvariable-decl
197Common Var(warn_variable_decl)
198Warn about variable-sized declarations.
199
200Wvolatile-register-var
201Common Var(warn_register_var)
202Warn when a register variable is declared volatile
203
204aux-info
205Common Separate
206-aux-info <file>	Emit declaration information into <file>
207
208aux-info=
209Common Joined
210
211auxbase
212Common Separate
213
214auxbase-strip
215Common Separate
216
217d
218Common Joined
219-d<letters>	Enable dumps from specific passes of the compiler
220
221dumpbase
222Common Separate
223-dumpbase <file>	Set the file basename to be used for dumps
224
225; The version of the C++ ABI in use.  The following values are allowed:
226;
227; 0: The version of the ABI believed most conformant with the C++ ABI
228;    specification.  This ABI may change as bugs are discovered and fixed.
229;    Therefore, 0 will not necessarily indicate the same ABI in different
230;    versions of G++.
231;
232; 1: The version of the ABI first used in G++ 3.2.
233;
234; Additional positive integers will be assigned as new versions of
235; the ABI become the default version of the ABI.
236fabi-version=
237Common Joined UInteger Var(flag_abi_version) Init(2)
238
239falign-functions
240Common Report Var(align_functions,0)
241Align the start of functions
242
243falign-functions=
244Common RejectNegative Joined UInteger
245
246falign-jumps
247Common Report Var(align_jumps,0)
248Align labels which are only reached by jumping
249
250falign-jumps=
251Common RejectNegative Joined UInteger
252
253falign-labels
254Common Report Var(align_labels,0)
255Align all labels
256
257falign-labels=
258Common RejectNegative Joined UInteger
259
260falign-loops
261Common Report Var(align_loops)
262Align the start of loops
263
264falign-loops=
265Common RejectNegative Joined UInteger
266
267; This flag is only tested if alias checking is enabled.
268; 0 if pointer arguments may alias each other.  True in C.
269; 1 if pointer arguments may not alias each other but may alias
270;   global variables.
271; 2 if pointer arguments may not alias each other and may not
272;   alias global variables.
273; 3 if pointer arguments may not alias anything.  True in Fortran.
274;   Set by the front end.
275fargument-alias
276Common Report Var(flag_argument_noalias,0)
277Specify that arguments may alias each other and globals
278
279fargument-noalias
280Common Report Var(flag_argument_noalias,1) VarExists
281Assume arguments may alias globals but not each other
282
283fargument-noalias-global
284Common Report Var(flag_argument_noalias,2) VarExists
285Assume arguments alias neither each other nor globals
286
287fargument-noalias-anything
288Common Report Var(flag_argument_noalias,3) VarExists
289Assume arguments alias no other storage
290
291fasynchronous-unwind-tables
292Common Report Var(flag_asynchronous_unwind_tables)
293Generate unwind tables that are exact at each instruction boundary
294
295; -fcheck-bounds causes gcc to generate array bounds checks.
296; For C, C++ and ObjC: defaults off.
297; For Java: defaults to on.
298; For Fortran: defaults to off.
299fbounds-check
300Common Report Var(flag_bounds_check)
301Generate code to check bounds before indexing arrays
302
303fbranch-count-reg
304Common Report Var(flag_branch_on_count_reg) Init(1)
305Replace add, compare, branch with branch on count register
306
307fbranch-probabilities
308Common Report Var(flag_branch_probabilities)
309Use profiling information for branch probabilities
310
311fbranch-target-load-optimize
312Common Report Var(flag_branch_target_load_optimize)
313Perform branch target load optimization before prologue / epilogue threading
314
315fbranch-target-load-optimize2
316Common Report Var(flag_branch_target_load_optimize2)
317Perform branch target load optimization after prologue / epilogue threading
318
319fbtr-bb-exclusive
320Common Report Var(flag_btr_bb_exclusive)
321Restrict target load migration not to re-use registers in any basic block
322
323fcall-saved-
324Common Joined RejectNegative
325-fcall-saved-<register>	Mark <register> as being preserved across functions
326
327fcall-used-
328Common Joined RejectNegative
329-fcall-used-<register>	Mark <register> as being corrupted by function calls
330
331; Nonzero for -fcaller-saves: allocate values in regs that need to
332; be saved across function calls, if that produces overall better code.
333; Optional now, so people can test it.
334fcaller-saves
335Common Report Var(flag_caller_saves)
336Save registers around function calls
337
338fcommon
339Common Report Var(flag_no_common,0)
340Do not put uninitialized globals in the common section
341
342fcprop-registers
343Common Report Var(flag_cprop_registers)
344Perform a register copy-propagation optimization pass
345
346fcrossjumping
347Common Report Var(flag_crossjumping)
348Perform cross-jumping optimization
349
350fcse-follow-jumps
351Common Report Var(flag_cse_follow_jumps)
352When running CSE, follow jumps to their targets
353
354fcse-skip-blocks
355Common Report Var(flag_cse_skip_blocks)
356When running CSE, follow conditional jumps
357
358fcx-limited-range
359Common Report Var(flag_cx_limited_range)
360Omit range reduction step when performing complex division
361
362fdata-sections
363Common Report Var(flag_data_sections)
364Place data items into their own section
365
366; Nonzero for -fdefer-pop: don't pop args after each function call
367; instead save them up to pop many calls' args with one insns.
368fdefer-pop
369Common Report Var(flag_defer_pop)
370Defer popping functions args from stack until later
371
372fdelayed-branch
373Common Report Var(flag_delayed_branch)
374Attempt to fill delay slots of branch instructions
375
376fdelete-null-pointer-checks
377Common Report Var(flag_delete_null_pointer_checks)
378Delete useless null pointer checks
379
380fdiagnostics-show-location=
381Common Joined RejectNegative
382-fdiagnostics-show-location=[once|every-line]	How often to emit source location at the beginning of line-wrapped diagnostics
383
384fdiagnostics-show-option
385Common
386Amend appropriate diagnostic messages with the command line option that controls them
387
388fdump-
389Common Joined RejectNegative
390-fdump-<type>	Dump various compiler internals to a file
391
392fdump-noaddr
393Common Report Var(flag_dump_noaddr)
394Suppress output of addresses in debugging dumps
395
396fdump-unnumbered
397Common Report Var(flag_dump_unnumbered) VarExists
398Suppress output of instruction numbers, line number notes and addresses in debugging dumps
399
400fearly-inlining
401Common Report Var(flag_early_inlining) Init(1)
402Perform early inlining
403
404feliminate-dwarf2-dups
405Common Report Var(flag_eliminate_dwarf2_dups)
406Perform DWARF2 duplicate elimination
407
408feliminate-unused-debug-symbols
409Common Report Var(flag_debug_only_used_symbols)
410Perform unused type elimination in debug info
411
412feliminate-unused-debug-types
413Common Report Var(flag_eliminate_unused_debug_types) Init(1)
414Perform unused type elimination in debug info
415
416femit-class-debug-always
417Common Report Var(flag_emit_class_debug_always) Init(1)
418Do not suppress C++ class debug information.
419
420fexceptions
421Common Report Var(flag_exceptions)
422Enable exception handling
423
424fexpensive-optimizations
425Common Report Var(flag_expensive_optimizations)
426Perform a number of minor, expensive optimizations
427
428ffast-math
429Common
430
431ffinite-math-only
432Common Report Var(flag_finite_math_only)
433Assume no NaNs or infinities are generated
434
435ffixed-
436Common Joined RejectNegative
437-ffixed-<register>	Mark <register> as being unavailable to the compiler
438
439ffloat-store
440Common Report Var(flag_float_store)
441Don't allocate floats and doubles in extended-precision registers
442
443; Nonzero for -fforce-addr: load memory address into a register before
444; reference to memory.  This makes better cse but slower compilation.
445fforce-addr
446Common Report Var(flag_force_addr)
447Copy memory address constants into registers before use
448
449; Nonzero for -fforce-mem: load memory value into a register
450; before arithmetic on it.  This makes better cse but slower compilation.
451fforce-mem
452Common Report Var(flag_force_mem)
453Copy memory operands into registers before use
454
455; Nonzero means don't put addresses of constant functions in registers.
456; Used for compiling the Unix kernel, where strange substitutions are
457; done on the assembly output.
458ffunction-cse
459Common Report Var(flag_no_function_cse,0)
460Allow function addresses to be held in registers
461
462ffunction-sections
463Common Report Var(flag_function_sections)
464Place each function into its own section
465
466fgcse
467Common Report Var(flag_gcse)
468Perform global common subexpression elimination
469
470fgcse-lm
471Common Report Var(flag_gcse_lm) Init(1)
472Perform enhanced load motion during global common subexpression elimination
473
474fgcse-sm
475Common Report Var(flag_gcse_sm) Init(0)
476Perform store motion after global common subexpression elimination
477
478fgcse-las
479Common Report Var(flag_gcse_las) Init(0)
480Perform redundant load after store elimination in global common subexpression
481elimination
482
483fgcse-after-reload
484Common Report Var(flag_gcse_after_reload)
485Perform global common subexpression elimination after register allocation
486has finished
487
488fguess-branch-probability
489Common Report Var(flag_guess_branch_prob)
490Enable guessing of branch probabilities
491
492; Nonzero means ignore `#ident' directives.  0 means handle them.
493; Generate position-independent code for executables if possible
494; On SVR4 targets, it also controls whether or not to emit a
495; string identifying the compiler.
496fident
497Common Report Var(flag_no_ident,0)
498Process #ident directives
499
500fif-conversion
501Common Report Var(flag_if_conversion)
502Perform conversion of conditional jumps to branchless equivalents
503
504fif-conversion2
505Common Report Var(flag_if_conversion2)
506Perform conversion of conditional jumps to conditional execution
507
508; -finhibit-size-directive inhibits output of .size for ELF.
509; This is used only for compiling crtstuff.c,
510; and it may be extended to other effects
511; needed for crtstuff.c on other systems.
512finhibit-size-directive
513Common Report Var(flag_inhibit_size_directive)
514Do not generate .size directives
515
516; Nonzero means that functions declared `inline' will be treated
517; as `static'.  Prevents generation of zillions of copies of unused
518; static inline functions; instead, `inlines' are written out
519; only when actually used.  Used in conjunction with -g.  Also
520; does the right thing with #pragma interface.
521finline
522Common Report Var(flag_no_inline,0) Init(2)
523Pay attention to the \"inline\" keyword
524
525finline-functions
526Common Report Var(flag_inline_functions)
527Integrate simple functions into their callers
528
529finline-functions-called-once
530Common Report Var(flag_inline_functions_called_once) Init(1)
531Integrate functions called once into their callers
532
533finline-limit-
534Common RejectNegative Joined UInteger
535
536finline-limit=
537Common RejectNegative Joined UInteger
538-finline-limit=<number>	Limit the size of inlined functions to <number>
539
540finstrument-functions
541Common Report Var(flag_instrument_function_entry_exit)
542Instrument function entry and exit with profiling calls
543
544finstrument-functions-exclude-function-list=
545Common RejectNegative Joined
546-finstrument-functions-exclude-function-list=name,...  Do not instrument listed functions
547
548finstrument-functions-exclude-file-list=
549Common RejectNegative Joined
550-finstrument-functions-exclude-file-list=filename,...  Do not instrument functions listed in files
551
552fipa-cp
553Common Report Var(flag_ipa_cp)
554Perform Interprocedural constant propagation
555
556fipa-pure-const
557Common Report Var(flag_ipa_pure_const) Init(0)
558Discover pure and const functions
559
560fipa-pta
561Common Report Var(flag_ipa_pta) Init(0)
562Perform interprocedural points-to analysis
563
564fipa-reference
565Common Report Var(flag_ipa_reference) Init(0)
566Discover readonly and non addressable static variables
567
568fipa-type-escape
569Common Report Var(flag_ipa_type_escape) Init(0)
570Type based escape and alias analysis
571
572fivopts
573Common Report Var(flag_ivopts) Init(1)
574Optimize induction variables on trees
575
576fjump-tables
577Common Var(flag_jump_tables) Init(1)
578Use jump tables for sufficiently large switch statements
579
580fkeep-inline-functions
581Common Report Var(flag_keep_inline_functions)
582Generate code for functions even if they are fully inlined
583
584fkeep-static-consts
585Common Report Var(flag_keep_static_consts) Init(1)
586Emit static const variables even if they are not used
587
588fleading-underscore
589Common Report Var(flag_leading_underscore) Init(-1)
590Give external symbols a leading underscore
591
592floop-optimize
593Common
594Does nothing.  Preserved for backward compatibility.
595
596fmath-errno
597Common Report Var(flag_errno_math) Init(0)
598Set errno after built-in math functions
599
600fmem-report
601Common Report Var(mem_report)
602Report on permanent memory allocation
603
604; This will attempt to merge constant section constants, if 1 only
605; string constants and constants from constant pool, if 2 also constant
606; variables.
607fmerge-all-constants
608Common Report Var(flag_merge_constants,2) Init(1)
609Attempt to merge identical constants and constant variables
610
611fmerge-constants
612Common Report Var(flag_merge_constants,1) VarExists
613Attempt to merge identical constants across compilation units
614
615fmessage-length=
616Common RejectNegative Joined UInteger
617-fmessage-length=<number>	Limit diagnostics to <number> characters per line.  0 suppresses line-wrapping
618
619fmodulo-sched
620Common Report Var(flag_modulo_sched)
621Perform SMS based modulo scheduling before the first scheduling pass
622
623fmove-loop-invariants
624Common Report Var(flag_move_loop_invariants) Init(1)
625Move loop invariant computations out of loops
626
627fmudflap
628Common RejectNegative Report Var(flag_mudflap)
629Add mudflap bounds-checking instrumentation for single-threaded program
630
631fmudflapth
632Common RejectNegative Report VarExists Var(flag_mudflap,2)
633Add mudflap bounds-checking instrumentation for multi-threaded program
634
635fmudflapir
636Common RejectNegative Report Var(flag_mudflap_ignore_reads)
637Ignore read operations when inserting mudflap instrumentation
638
639freschedule-modulo-scheduled-loops
640Common Report Var(flag_resched_modulo_sched)
641Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
642
643fnon-call-exceptions
644Common Report Var(flag_non_call_exceptions)
645Support synchronous non-call exceptions
646
647fomit-frame-pointer
648Common Report Var(flag_omit_frame_pointer)
649When possible do not generate stack frames
650
651foptimize-register-move
652Common Report Var(flag_regmove)
653Do the full register move optimization pass
654
655foptimize-sibling-calls
656Common Report Var(flag_optimize_sibling_calls)
657Optimize sibling and tail recursive calls
658
659fpack-struct
660Common Report Var(flag_pack_struct)
661Pack structure members together without holes
662
663fpack-struct=
664Common RejectNegative Joined UInteger
665-fpack-struct=<number>	Set initial maximum structure member alignment
666
667fpcc-struct-return
668Common Report Var(flag_pcc_struct_return,1) VarExists
669Return small aggregates in memory, not registers
670
671fpeel-loops
672Common Report Var(flag_peel_loops)
673Perform loop peeling
674
675fpeephole
676Common Report Var(flag_no_peephole,0)
677Enable machine specific peephole optimizations
678
679fpeephole2
680Common Report Var(flag_peephole2)
681Enable an RTL peephole pass before sched2
682
683fPIC
684Common Report Var(flag_pic,2)
685Generate position-independent code if possible (large mode)
686
687fPIE
688Common Report Var(flag_pie,2)
689Generate position-independent code for executables if possible (large mode)
690
691fpic
692Common Report Var(flag_pic,1) VarExists
693Generate position-independent code if possible (small mode)
694
695fpie
696Common Report Var(flag_pie,1) VarExists
697Generate position-independent code for executables if possible (small mode)
698
699fprefetch-loop-arrays
700Common Report Var(flag_prefetch_loop_arrays)
701Generate prefetch instructions, if available, for arrays in loops
702
703fprofile
704Common Report Var(profile_flag)
705Enable basic program profiling code
706
707fprofile-arcs
708Common Report Var(profile_arc_flag)
709Insert arc-based program profiling code
710
711fprofile-generate
712Common
713Enable common options for generating profile info for profile feedback directed optimizations
714
715fprofile-use
716Common
717Enable common options for performing profile feedback directed optimizations
718
719fprofile-values
720Common Report Var(flag_profile_values)
721Insert code to profile values of expressions
722
723frandom-seed
724Common
725
726frandom-seed=
727Common Joined RejectNegative
728-frandom-seed=<string>	Make compile reproducible using <string>
729
730freg-struct-return
731Common Report Var(flag_pcc_struct_return,0) VarExists
732Return small aggregates in registers
733
734fregmove
735Common Report Var(flag_regmove)
736Enables a register move optimization
737
738frename-registers
739Common Report Var(flag_rename_registers) Init(2)
740Perform a register renaming optimization pass
741
742freorder-blocks
743Common Report Var(flag_reorder_blocks)
744Reorder basic blocks to improve code placement
745
746freorder-blocks-and-partition
747Common Report Var(flag_reorder_blocks_and_partition)
748Reorder basic blocks and partition into hot and cold sections
749
750freorder-functions
751Common Report Var(flag_reorder_functions)
752Reorder functions to improve code placement
753
754frerun-cse-after-loop
755Common Report Var(flag_rerun_cse_after_loop) Init(2)
756Add a common subexpression elimination pass after loop optimizations
757
758frerun-loop-opt
759Common
760Does nothing.  Preserved for backward compatibility.
761
762frounding-math
763Common Report Var(flag_rounding_math)
764Disable optimizations that assume default FP rounding behavior
765
766fsched-interblock
767Common Report Var(flag_schedule_interblock) Init(1)
768Enable scheduling across basic blocks
769
770fsched-spec
771Common Report Var(flag_schedule_speculative) Init(1)
772Allow speculative motion of non-loads
773
774fsched-spec-load
775Common Report Var(flag_schedule_speculative_load)
776Allow speculative motion of some loads
777
778fsched-spec-load-dangerous
779Common Report Var(flag_schedule_speculative_load_dangerous)
780Allow speculative motion of more loads
781
782fsched-verbose=
783Common RejectNegative Joined
784-fsched-verbose=<number>	Set the verbosity level of the scheduler
785
786fsched2-use-superblocks
787Common Report Var(flag_sched2_use_superblocks)
788If scheduling post reload, do superblock scheduling
789
790fsched2-use-traces
791Common Report Var(flag_sched2_use_traces)
792If scheduling post reload, do trace scheduling
793
794fschedule-insns
795Common Report Var(flag_schedule_insns)
796Reschedule instructions before register allocation
797
798fschedule-insns2
799Common Report Var(flag_schedule_insns_after_reload)
800Reschedule instructions after register allocation
801
802; sched_stalled_insns means that insns can be moved prematurely from the queue
803; of stalled insns into the ready list.
804fsched-stalled-insns
805Common Report Var(flag_sched_stalled_insns)
806Allow premature scheduling of queued insns
807
808fsched-stalled-insns=
809Common RejectNegative Joined UInteger
810-fsched-stalled-insns=<number>	Set number of queued insns that can be prematurely scheduled
811
812; sched_stalled_insns_dep controls how many recently scheduled cycles will
813; be examined for a dependency on a stalled insn that is candidate for
814; premature removal from the queue of stalled insns into the ready list (has
815; an effect only if the flag 'sched_stalled_insns' is set).
816fsched-stalled-insns-dep
817Common Report Var(flag_sched_stalled_insns_dep,1) Init(1)
818Set dependence distance checking in premature scheduling of queued insns
819
820fsched-stalled-insns-dep=
821Common RejectNegative Joined UInteger
822-fsched-stalled-insns-dep=<number>	Set dependence distance checking in premature scheduling of queued insns
823
824fsection-anchors
825Common Report Var(flag_section_anchors)
826Access data in the same section from shared anchor points
827
828frtl-abstract-sequences
829Common Report Var(flag_rtl_seqabstr)
830Perform sequence abstraction optimization on RTL
831
832fsee
833Common Report Var(flag_see) Init(0)
834Eliminate redundant sign extensions using LCM.
835
836fshow-column
837Common C ObjC C++ ObjC++ Report Var(flag_show_column) Init(1)
838Show column numbers in diagnostics, when available.  Default on
839
840fsignaling-nans
841Common Report Var(flag_signaling_nans)
842Disable optimizations observable by IEEE signaling NaNs
843
844fsingle-precision-constant
845Common Report Var(flag_single_precision_constant)
846Convert floating point constants to single precision constants
847
848fsplit-ivs-in-unroller
849Common Report Var(flag_split_ivs_in_unroller) Init(1)
850Split lifetimes of induction variables when loops are unrolled
851
852fvariable-expansion-in-unroller
853Common Report Var(flag_variable_expansion_in_unroller)
854Apply variable expansion when loops are unrolled
855
856; Emit code to probe the stack, to help detect stack overflow; also
857; may cause large objects to be allocated dynamically.
858fstack-check
859Common Report Var(flag_stack_check)
860Insert stack checking code into the program
861
862fstack-limit
863Common
864
865fstack-limit-register=
866Common RejectNegative Joined
867-fstack-limit-register=<register>	Trap if the stack goes past <register>
868
869fstack-limit-symbol=
870Common RejectNegative Joined
871-fstack-limit-symbol=<name>	Trap if the stack goes past symbol <name>
872
873fstack-protector
874Common Report Var(flag_stack_protect, 1)
875Use propolice as a stack protection method
876
877fstack-protector-all
878Common Report RejectNegative Var(flag_stack_protect, 2) VarExists
879Use a stack protection method for every function
880
881fstrength-reduce
882Common
883Does nothing.  Preserved for backward compatibility.
884
885; Nonzero if we should do (language-dependent) alias analysis.
886; Typically, this analysis will assume that expressions of certain
887; types do not alias expressions of certain other types.  Only used
888; if alias analysis (in general) is enabled.
889fstrict-aliasing
890Common Report Var(flag_strict_aliasing)
891Assume strict aliasing rules apply
892
893fstrict-overflow
894Common Report Var(flag_strict_overflow)
895Treat signed overflow as undefined
896
897fsyntax-only
898Common Report Var(flag_syntax_only)
899Check for syntax errors, then stop
900
901ftest-coverage
902Common Report Var(flag_test_coverage)
903Create data files needed by \"gcov\"
904
905fthread-jumps
906Common Report Var(flag_thread_jumps)
907Perform jump threading optimizations
908
909ftime-report
910Common Report Var(time_report)
911Report the time taken by each compiler pass
912
913ftls-model=
914Common Joined RejectNegative
915-ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec]	Set the default thread-local storage code generation model
916
917ftoplevel-reorder
918Common Report Var(flag_toplevel_reorder) Init(1)
919Reorder top level functions, variables, and asms
920
921ftracer
922Common Report Var(flag_tracer)
923Perform superblock formation via tail duplication
924
925; Zero means that floating-point math operations cannot generate a
926; (user-visible) trap.  This is the case, for example, in nonstop
927; IEEE 754 arithmetic.
928ftrapping-math
929Common Report Var(flag_trapping_math) Init(1)
930Assume floating-point operations can trap
931
932ftrapv
933Common Report Var(flag_trapv)
934Trap for signed overflow in addition, subtraction and multiplication
935
936ftree-ccp
937Common Report Var(flag_tree_ccp)
938Enable SSA-CCP optimization on trees
939
940ftree-store-ccp
941Common Report Var(flag_tree_store_ccp)
942Enable SSA-CCP optimization for stores and loads
943
944ftree-ch
945Common Report Var(flag_tree_ch)
946Enable loop header copying on trees
947
948ftree-combine-temps
949Common Report Var(flag_tree_combine_temps)
950Coalesce memory temporaries in the SSA->normal pass
951
952ftree-copyrename
953Common Report Var(flag_tree_copyrename)
954Replace SSA temporaries with better names in copies
955
956ftree-copy-prop
957Common Report Var(flag_tree_copy_prop)
958Enable copy propagation on trees
959
960ftree-store-copy-prop
961Common Report Var(flag_tree_store_copy_prop)
962Enable copy propagation for stores and loads
963
964ftree-dce
965Common Report Var(flag_tree_dce)
966Enable SSA dead code elimination optimization on trees
967
968ftree-dominator-opts
969Common Report Var(flag_tree_dom)
970Enable dominator optimizations
971
972ftree-dse
973Common Report Var(flag_tree_dse)
974Enable dead store elimination
975
976ftree-fre
977Common Report Var(flag_tree_fre)
978Enable Full Redundancy Elimination (FRE) on trees
979
980ftree-loop-im
981Common Report Var(flag_tree_loop_im) Init(1)
982Enable loop invariant motion on trees
983
984ftree-loop-linear
985Common Report Var(flag_tree_loop_linear)
986Enable linear loop transforms on trees
987
988ftree-loop-ivcanon
989Common Report Var(flag_tree_loop_ivcanon) Init(1)
990Create canonical induction variables in loops
991
992ftree-loop-optimize
993Common Report Var(flag_tree_loop_optimize) Init(1)
994Enable loop optimizations on tree level
995
996ftree-pre
997Common Report Var(flag_tree_pre)
998Enable SSA-PRE optimization on trees
999
1000ftree-salias
1001Common Report Var(flag_tree_salias)
1002Perform structural alias analysis
1003
1004ftree-sink
1005Common Report Var(flag_tree_sink)
1006Enable SSA code sinking on trees
1007
1008ftree-sra
1009Common Report Var(flag_tree_sra)
1010Perform scalar replacement of aggregates
1011
1012ftree-ter
1013Common Report Var(flag_tree_ter)
1014Replace temporary expressions in the SSA->normal pass
1015
1016ftree-lrs
1017Common Report Var(flag_tree_live_range_split)
1018Perform live range splitting during the SSA->normal pass
1019
1020ftree-vrp
1021Common Report Var(flag_tree_vrp) Init(0)
1022Perform Value Range Propagation on trees
1023
1024funit-at-a-time
1025Common Report Var(flag_unit_at_a_time)
1026Compile whole compilation unit at a time
1027
1028funroll-loops
1029Common Report Var(flag_unroll_loops)
1030Perform loop unrolling when iteration count is known
1031
1032funroll-all-loops
1033Common Report Var(flag_unroll_all_loops)
1034Perform loop unrolling for all loops
1035
1036; Nonzero means that loop optimizer may assume that the induction variables
1037; that control loops do not overflow and that the loops with nontrivial
1038; exit condition are not infinite
1039funsafe-loop-optimizations
1040Common Report Var(flag_unsafe_loop_optimizations)
1041Allow loop optimizations to assume that the loops behave in normal way
1042
1043; Nonzero means that unsafe floating-point math optimizations are allowed
1044; for the sake of speed.  IEEE compliance is not guaranteed, and operations
1045; are allowed to assume that their arguments and results are "normal"
1046; (e.g., nonnegative for SQRT).
1047funsafe-math-optimizations
1048Common Report Var(flag_unsafe_math_optimizations)
1049Allow math optimizations that may violate IEEE or ISO standards
1050
1051funswitch-loops
1052Common Report Var(flag_unswitch_loops)
1053Perform loop unswitching
1054
1055funwind-tables
1056Common Report Var(flag_unwind_tables)
1057Just generate unwind tables for exception handling
1058
1059fvar-tracking
1060Common Report Var(flag_var_tracking) VarExists
1061Perform variable tracking
1062
1063ftree-vectorize
1064Common Report Var(flag_tree_vectorize)
1065Enable loop vectorization on trees
1066
1067ftree-vect-loop-version
1068Common Report Var(flag_tree_vect_loop_version) Init(1)
1069Enable loop versioning when doing loop vectorization on trees
1070
1071ftree-vectorizer-verbose=
1072Common RejectNegative Joined
1073-ftree-vectorizer-verbose=<number>	Set the verbosity level of the vectorizer
1074
1075; -fverbose-asm causes extra commentary information to be produced in
1076; the generated assembly code (to make it more readable).  This option
1077; is generally only of use to those who actually need to read the
1078; generated assembly code (perhaps while debugging the compiler itself).
1079; -fno-verbose-asm, the default, causes the extra information
1080; to not be added and is useful when comparing two assembler files.
1081fverbose-asm
1082Common Report Var(flag_verbose_asm)
1083Add extra commentary to assembler output
1084
1085fvisibility=
1086Common Joined RejectNegative
1087-fvisibility=[default|internal|hidden|protected]	Set the default symbol visibility
1088
1089
1090fvpt
1091Common Report Var(flag_value_profile_transformations)
1092Use expression value profiles in optimizations
1093
1094fweb
1095Common Report Var(flag_web) Init(2)
1096Construct webs and split unrelated uses of single variable
1097
1098fwhole-program
1099Common Report Var(flag_whole_program) Init(0)
1100Perform whole program optimizations
1101
1102fwrapv
1103Common Report Var(flag_wrapv)
1104Assume signed arithmetic overflow wraps around
1105
1106fzero-initialized-in-bss
1107Common Report Var(flag_zero_initialized_in_bss) Init(1)
1108Put zero initialized data in the bss section
1109
1110g
1111Common JoinedOrMissing
1112Generate debug information in default format
1113
1114gcoff
1115Common JoinedOrMissing Negative(gdwarf-2)
1116Generate debug information in COFF format
1117
1118gdwarf-2
1119Common JoinedOrMissing Negative(gstabs)
1120Generate debug information in DWARF v2 format
1121
1122ggdb
1123Common JoinedOrMissing
1124Generate debug information in default extended format
1125
1126gstabs
1127Common JoinedOrMissing Negative(gstabs+)
1128Generate debug information in STABS format
1129
1130gstabs+
1131Common JoinedOrMissing Negative(gvms)
1132Generate debug information in extended STABS format
1133
1134gvms
1135Common JoinedOrMissing Negative(gxcoff)
1136Generate debug information in VMS format
1137
1138gxcoff
1139Common JoinedOrMissing Negative(gxcoff+)
1140Generate debug information in XCOFF format
1141
1142gxcoff+
1143Common JoinedOrMissing Negative(gcoff)
1144Generate debug information in extended XCOFF format
1145
1146o
1147Common Joined Separate
1148-o <file>	Place output into <file>
1149
1150p
1151Common Var(profile_flag)
1152Enable function profiling
1153
1154pedantic
1155Common Var(pedantic)
1156Issue warnings needed for strict compliance to the standard
1157
1158pedantic-errors
1159Common
1160Like -pedantic but issue them as errors
1161
1162quiet
1163Common Var(quiet_flag)
1164Do not display functions compiled or elapsed time
1165
1166version
1167Common Var(version_flag)
1168Display the compiler's version
1169
1170w
1171Common Var(inhibit_warnings)
1172Suppress warnings
1173
1174; This comment is to ensure we retain the blank line above.
1175