xref: /openbsd/gnu/gcc/gcc/common.opt (revision 3e83d15b)
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 a function is using more than <number> bytes of stack space for their local variables.
103
104Wstack-larger-than-
105Common RejectNegative Joined UInteger
106-Wstack-larger-than-<number> Warn if a function is using more than <number> bytes of stack space for their local variables.
107
108Wunsafe-loop-optimizations
109Common Var(warn_unsafe_loop_optimizations)
110Warn if the loop cannot be optimized due to nontrivial assumptions.
111
112Wmissing-noreturn
113Common Var(warn_missing_noreturn)
114Warn about functions which might be candidates for __attribute__((noreturn))
115
116Woverflow
117Common Var(warn_overflow) Init(1)
118Warn about overflow in arithmetic expressions
119
120Wpacked
121Common Var(warn_packed)
122Warn when the packed attribute has no effect on struct layout
123
124Wpadded
125Common Var(warn_padded)
126Warn when padding is required to align structure members
127
128Wshadow
129Common Var(warn_shadow)
130Warn when one local variable shadows another
131
132Wstack-protector
133Common Var(warn_stack_protect)
134Warn when not issuing stack smashing protection for some reason
135
136Wstrict-aliasing
137Common
138Warn about code which might break strict aliasing rules
139
140Wstrict-aliasing=
141Common Joined UInteger
142Warn about code which might break strict aliasing rules
143
144Wstrict-overflow
145Common
146Warn about optimizations that assume that signed overflow is undefined
147
148Wstrict-overflow=
149Common Joined UInteger
150Warn about optimizations that assume that signed overflow is undefined
151
152Wswitch
153Common Var(warn_switch)
154Warn about enumerated switches, with no default, missing a case
155
156Wswitch-default
157Common Var(warn_switch_default)
158Warn about enumerated switches missing a \"default:\" statement
159
160Wswitch-enum
161Common Var(warn_switch_enum)
162Warn about all enumerated switches missing a specific case
163
164Wsystem-headers
165Common Var(warn_system_headers) Init(1)
166Do not suppress warnings from system headers
167
168Wuninitialized
169Common Var(warn_uninitialized)
170Warn about uninitialized automatic variables
171
172Wunreachable-code
173Common Var(warn_notreached)
174Warn about code that will never be executed
175
176Wunused
177Common
178Enable all -Wunused- warnings
179
180Wunused-function
181Common Var(warn_unused_function)
182Warn when a function is unused
183
184Wunused-label
185Common Var(warn_unused_label)
186Warn when a label is unused
187
188Wunused-parameter
189Common Var(warn_unused_parameter)
190Warn when a function parameter is unused
191
192Wunused-value
193Common Var(warn_unused_value)
194Warn when an expression value is unused
195
196Wunused-variable
197Common Var(warn_unused_variable)
198Warn when a variable is unused
199
200Wvariable-decl
201Common Var(warn_variable_decl)
202Warn about variable-sized declarations.
203
204Wvolatile-register-var
205Common Var(warn_register_var)
206Warn when a register variable is declared volatile
207
208aux-info
209Common Separate
210-aux-info <file>	Emit declaration information into <file>
211
212aux-info=
213Common Joined
214
215auxbase
216Common Separate
217
218auxbase-strip
219Common Separate
220
221d
222Common Joined
223-d<letters>	Enable dumps from specific passes of the compiler
224
225dumpbase
226Common Separate
227-dumpbase <file>	Set the file basename to be used for dumps
228
229; The version of the C++ ABI in use.  The following values are allowed:
230;
231; 0: The version of the ABI believed most conformant with the C++ ABI
232;    specification.  This ABI may change as bugs are discovered and fixed.
233;    Therefore, 0 will not necessarily indicate the same ABI in different
234;    versions of G++.
235;
236; 1: The version of the ABI first used in G++ 3.2.
237;
238; Additional positive integers will be assigned as new versions of
239; the ABI become the default version of the ABI.
240fabi-version=
241Common Joined UInteger Var(flag_abi_version) Init(2)
242
243falign-functions
244Common Report Var(align_functions,0)
245Align the start of functions
246
247falign-functions=
248Common RejectNegative Joined UInteger
249
250falign-jumps
251Common Report Var(align_jumps,0)
252Align labels which are only reached by jumping
253
254falign-jumps=
255Common RejectNegative Joined UInteger
256
257falign-labels
258Common Report Var(align_labels,0)
259Align all labels
260
261falign-labels=
262Common RejectNegative Joined UInteger
263
264falign-loops
265Common Report Var(align_loops)
266Align the start of loops
267
268falign-loops=
269Common RejectNegative Joined UInteger
270
271; This flag is only tested if alias checking is enabled.
272; 0 if pointer arguments may alias each other.  True in C.
273; 1 if pointer arguments may not alias each other but may alias
274;   global variables.
275; 2 if pointer arguments may not alias each other and may not
276;   alias global variables.
277; 3 if pointer arguments may not alias anything.  True in Fortran.
278;   Set by the front end.
279fargument-alias
280Common Report Var(flag_argument_noalias,0)
281Specify that arguments may alias each other and globals
282
283fargument-noalias
284Common Report Var(flag_argument_noalias,1) VarExists
285Assume arguments may alias globals but not each other
286
287fargument-noalias-global
288Common Report Var(flag_argument_noalias,2) VarExists
289Assume arguments alias neither each other nor globals
290
291fargument-noalias-anything
292Common Report Var(flag_argument_noalias,3) VarExists
293Assume arguments alias no other storage
294
295fasynchronous-unwind-tables
296Common Report Var(flag_asynchronous_unwind_tables)
297Generate unwind tables that are exact at each instruction boundary
298
299; -fcheck-bounds causes gcc to generate array bounds checks.
300; For C, C++ and ObjC: defaults off.
301; For Java: defaults to on.
302; For Fortran: defaults to off.
303fbounds-check
304Common Report Var(flag_bounds_check)
305Generate code to check bounds before indexing arrays
306
307fbranch-count-reg
308Common Report Var(flag_branch_on_count_reg) Init(1)
309Replace add, compare, branch with branch on count register
310
311fbranch-probabilities
312Common Report Var(flag_branch_probabilities)
313Use profiling information for branch probabilities
314
315fbranch-target-load-optimize
316Common Report Var(flag_branch_target_load_optimize)
317Perform branch target load optimization before prologue / epilogue threading
318
319fbranch-target-load-optimize2
320Common Report Var(flag_branch_target_load_optimize2)
321Perform branch target load optimization after prologue / epilogue threading
322
323fbtr-bb-exclusive
324Common Report Var(flag_btr_bb_exclusive)
325Restrict target load migration not to re-use registers in any basic block
326
327fcall-saved-
328Common Joined RejectNegative
329-fcall-saved-<register>	Mark <register> as being preserved across functions
330
331fcall-used-
332Common Joined RejectNegative
333-fcall-used-<register>	Mark <register> as being corrupted by function calls
334
335; Nonzero for -fcaller-saves: allocate values in regs that need to
336; be saved across function calls, if that produces overall better code.
337; Optional now, so people can test it.
338fcaller-saves
339Common Report Var(flag_caller_saves)
340Save registers around function calls
341
342fcommon
343Common Report Var(flag_no_common,0)
344Do not put uninitialized globals in the common section
345
346fcprop-registers
347Common Report Var(flag_cprop_registers)
348Perform a register copy-propagation optimization pass
349
350fcrossjumping
351Common Report Var(flag_crossjumping)
352Perform cross-jumping optimization
353
354fcse-follow-jumps
355Common Report Var(flag_cse_follow_jumps)
356When running CSE, follow jumps to their targets
357
358fcse-skip-blocks
359Common Report Var(flag_cse_skip_blocks)
360When running CSE, follow conditional jumps
361
362fcx-limited-range
363Common Report Var(flag_cx_limited_range)
364Omit range reduction step when performing complex division
365
366fdata-sections
367Common Report Var(flag_data_sections)
368Place data items into their own section
369
370; Nonzero for -fdefer-pop: don't pop args after each function call
371; instead save them up to pop many calls' args with one insns.
372fdefer-pop
373Common Report Var(flag_defer_pop)
374Defer popping functions args from stack until later
375
376fdelayed-branch
377Common Report Var(flag_delayed_branch)
378Attempt to fill delay slots of branch instructions
379
380fdelete-null-pointer-checks
381Common Report Var(flag_delete_null_pointer_checks)
382Delete useless null pointer checks
383
384fdiagnostics-show-location=
385Common Joined RejectNegative
386-fdiagnostics-show-location=[once|every-line]	How often to emit source location at the beginning of line-wrapped diagnostics
387
388fdiagnostics-show-option
389Common
390Amend appropriate diagnostic messages with the command line option that controls them
391
392fdump-
393Common Joined RejectNegative
394-fdump-<type>	Dump various compiler internals to a file
395
396fdump-noaddr
397Common Report Var(flag_dump_noaddr)
398Suppress output of addresses in debugging dumps
399
400fdump-unnumbered
401Common Report Var(flag_dump_unnumbered) VarExists
402Suppress output of instruction numbers, line number notes and addresses in debugging dumps
403
404fearly-inlining
405Common Report Var(flag_early_inlining) Init(1)
406Perform early inlining
407
408feliminate-dwarf2-dups
409Common Report Var(flag_eliminate_dwarf2_dups)
410Perform DWARF2 duplicate elimination
411
412feliminate-unused-debug-symbols
413Common Report Var(flag_debug_only_used_symbols)
414Perform unused type elimination in debug info
415
416feliminate-unused-debug-types
417Common Report Var(flag_eliminate_unused_debug_types) Init(1)
418Perform unused type elimination in debug info
419
420femit-class-debug-always
421Common Report Var(flag_emit_class_debug_always) Init(1)
422Do not suppress C++ class debug information.
423
424fexceptions
425Common Report Var(flag_exceptions)
426Enable exception handling
427
428fexpensive-optimizations
429Common Report Var(flag_expensive_optimizations)
430Perform a number of minor, expensive optimizations
431
432ffast-math
433Common
434
435ffinite-math-only
436Common Report Var(flag_finite_math_only)
437Assume no NaNs or infinities are generated
438
439ffixed-
440Common Joined RejectNegative
441-ffixed-<register>	Mark <register> as being unavailable to the compiler
442
443ffloat-store
444Common Report Var(flag_float_store)
445Don't allocate floats and doubles in extended-precision registers
446
447; Nonzero for -fforce-addr: load memory address into a register before
448; reference to memory.  This makes better cse but slower compilation.
449fforce-addr
450Common Report Var(flag_force_addr)
451Copy memory address constants into registers before use
452
453; Nonzero for -fforce-mem: load memory value into a register
454; before arithmetic on it.  This makes better cse but slower compilation.
455fforce-mem
456Common Report Var(flag_force_mem)
457Copy memory operands into registers before use
458
459; Nonzero means don't put addresses of constant functions in registers.
460; Used for compiling the Unix kernel, where strange substitutions are
461; done on the assembly output.
462ffunction-cse
463Common Report Var(flag_no_function_cse,0)
464Allow function addresses to be held in registers
465
466ffunction-sections
467Common Report Var(flag_function_sections)
468Place each function into its own section
469
470fgcse
471Common Report Var(flag_gcse)
472Perform global common subexpression elimination
473
474fgcse-lm
475Common Report Var(flag_gcse_lm) Init(1)
476Perform enhanced load motion during global common subexpression elimination
477
478fgcse-sm
479Common Report Var(flag_gcse_sm) Init(0)
480Perform store motion after global common subexpression elimination
481
482fgcse-las
483Common Report Var(flag_gcse_las) Init(0)
484Perform redundant load after store elimination in global common subexpression
485elimination
486
487fgcse-after-reload
488Common Report Var(flag_gcse_after_reload)
489Perform global common subexpression elimination after register allocation
490has finished
491
492fguess-branch-probability
493Common Report Var(flag_guess_branch_prob)
494Enable guessing of branch probabilities
495
496; Nonzero means ignore `#ident' directives.  0 means handle them.
497; Generate position-independent code for executables if possible
498; On SVR4 targets, it also controls whether or not to emit a
499; string identifying the compiler.
500fident
501Common Report Var(flag_no_ident,0) Init(1)
502Process #ident directives
503
504fif-conversion
505Common Report Var(flag_if_conversion)
506Perform conversion of conditional jumps to branchless equivalents
507
508fif-conversion2
509Common Report Var(flag_if_conversion2)
510Perform conversion of conditional jumps to conditional execution
511
512; -finhibit-size-directive inhibits output of .size for ELF.
513; This is used only for compiling crtstuff.c,
514; and it may be extended to other effects
515; needed for crtstuff.c on other systems.
516finhibit-size-directive
517Common Report Var(flag_inhibit_size_directive)
518Do not generate .size directives
519
520; Nonzero means that functions declared `inline' will be treated
521; as `static'.  Prevents generation of zillions of copies of unused
522; static inline functions; instead, `inlines' are written out
523; only when actually used.  Used in conjunction with -g.  Also
524; does the right thing with #pragma interface.
525finline
526Common Report Var(flag_no_inline,0) Init(2)
527Pay attention to the \"inline\" keyword
528
529finline-functions
530Common Report Var(flag_inline_functions)
531Integrate simple functions into their callers
532
533finline-functions-called-once
534Common Report Var(flag_inline_functions_called_once) Init(1)
535Integrate functions called once into their callers
536
537finline-limit-
538Common RejectNegative Joined UInteger
539
540finline-limit=
541Common RejectNegative Joined UInteger
542-finline-limit=<number>	Limit the size of inlined functions to <number>
543
544finstrument-functions
545Common Report Var(flag_instrument_function_entry_exit)
546Instrument function entry and exit with profiling calls
547
548fipa-cp
549Common Report Var(flag_ipa_cp)
550Perform Interprocedural constant propagation
551
552fipa-pure-const
553Common Report Var(flag_ipa_pure_const) Init(0)
554Discover pure and const functions
555
556fipa-pta
557Common Report Var(flag_ipa_pta) Init(0)
558Perform interprocedural points-to analysis
559
560fipa-reference
561Common Report Var(flag_ipa_reference) Init(0)
562Discover readonly and non addressable static variables
563
564fipa-type-escape
565Common Report Var(flag_ipa_type_escape) Init(0)
566Type based escape and alias analysis
567
568fivopts
569Common Report Var(flag_ivopts) Init(1)
570Optimize induction variables on trees
571
572fjump-tables
573Common Var(flag_jump_tables) Init(JUMP_TABLES_DEFAULT)
574Use jump tables for sufficiently large switch statements
575
576fkeep-inline-functions
577Common Report Var(flag_keep_inline_functions)
578Generate code for functions even if they are fully inlined
579
580fkeep-static-consts
581Common Report Var(flag_keep_static_consts) Init(1)
582Emit static const variables even if they are not used
583
584fleading-underscore
585Common Report Var(flag_leading_underscore) Init(-1)
586Give external symbols a leading underscore
587
588floop-optimize
589Common
590Does nothing.  Preserved for backward compatibility.
591
592fmath-errno
593Common Report Var(flag_errno_math) Init(1)
594Set errno after built-in math functions
595
596fmem-report
597Common Report Var(mem_report)
598Report on permanent memory allocation
599
600; This will attempt to merge constant section constants, if 1 only
601; string constants and constants from constant pool, if 2 also constant
602; variables.
603fmerge-all-constants
604Common Report Var(flag_merge_constants,2) Init(1)
605Attempt to merge identical constants and constant variables
606
607fmerge-constants
608Common Report Var(flag_merge_constants,1) VarExists
609Attempt to merge identical constants across compilation units
610
611fmessage-length=
612Common RejectNegative Joined UInteger
613-fmessage-length=<number>	Limit diagnostics to <number> characters per line.  0 suppresses line-wrapping
614
615fmodulo-sched
616Common Report Var(flag_modulo_sched)
617Perform SMS based modulo scheduling before the first scheduling pass
618
619fmove-loop-invariants
620Common Report Var(flag_move_loop_invariants) Init(1)
621Move loop invariant computations out of loops
622
623fmudflap
624Common RejectNegative Report Var(flag_mudflap)
625Add mudflap bounds-checking instrumentation for single-threaded program
626
627fmudflapth
628Common RejectNegative Report VarExists Var(flag_mudflap,2)
629Add mudflap bounds-checking instrumentation for multi-threaded program
630
631fmudflapir
632Common RejectNegative Report Var(flag_mudflap_ignore_reads)
633Ignore read operations when inserting mudflap instrumentation
634
635freschedule-modulo-scheduled-loops
636Common Report Var(flag_resched_modulo_sched)
637Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
638
639fnon-call-exceptions
640Common Report Var(flag_non_call_exceptions)
641Support synchronous non-call exceptions
642
643fomit-frame-pointer
644Common Report Var(flag_omit_frame_pointer)
645When possible do not generate stack frames
646
647foptimize-register-move
648Common Report Var(flag_regmove)
649Do the full register move optimization pass
650
651foptimize-sibling-calls
652Common Report Var(flag_optimize_sibling_calls)
653Optimize sibling and tail recursive calls
654
655fpack-struct
656Common Report Var(flag_pack_struct)
657Pack structure members together without holes
658
659fpack-struct=
660Common RejectNegative Joined UInteger
661-fpack-struct=<number>	Set initial maximum structure member alignment
662
663fpcc-struct-return
664Common Report Var(flag_pcc_struct_return,1) VarExists
665Return small aggregates in memory, not registers
666
667fpeel-loops
668Common Report Var(flag_peel_loops)
669Perform loop peeling
670
671fpeephole
672Common Report Var(flag_no_peephole,0)
673Enable machine specific peephole optimizations
674
675fpeephole2
676Common Report Var(flag_peephole2)
677Enable an RTL peephole pass before sched2
678
679fPIC
680Common Report Var(flag_pic,2)
681Generate position-independent code if possible (large mode)
682
683fPIE
684Common Report Var(flag_pie,2) Init(PIE_DEFAULT)
685Generate position-independent code for executables if possible (large mode)
686
687fpic
688Common Report Var(flag_pic,1) VarExists
689Generate position-independent code if possible (small mode)
690
691fpie
692Common Report Var(flag_pie,1) VarExists
693Generate position-independent code for executables if possible (small mode)
694
695fprefetch-loop-arrays
696Common Report Var(flag_prefetch_loop_arrays)
697Generate prefetch instructions, if available, for arrays in loops
698
699fprofile
700Common Report Var(profile_flag)
701Enable basic program profiling code
702
703fprofile-arcs
704Common Report Var(profile_arc_flag)
705Insert arc-based program profiling code
706
707fprofile-generate
708Common
709Enable common options for generating profile info for profile feedback directed optimizations
710
711fprofile-use
712Common
713Enable common options for performing profile feedback directed optimizations
714
715fprofile-values
716Common Report Var(flag_profile_values)
717Insert code to profile values of expressions
718
719frandom-seed
720Common
721
722frandom-seed=
723Common Joined RejectNegative
724-frandom-seed=<string>	Make compile reproducible using <string>
725
726freg-struct-return
727Common Report Var(flag_pcc_struct_return,0) VarExists
728Return small aggregates in registers
729
730fregmove
731Common Report Var(flag_regmove)
732Enables a register move optimization
733
734frename-registers
735Common Report Var(flag_rename_registers) Init(2)
736Perform a register renaming optimization pass
737
738freorder-blocks
739Common Report Var(flag_reorder_blocks)
740Reorder basic blocks to improve code placement
741
742freorder-blocks-and-partition
743Common Report Var(flag_reorder_blocks_and_partition)
744Reorder basic blocks and partition into hot and cold sections
745
746freorder-functions
747Common Report Var(flag_reorder_functions)
748Reorder functions to improve code placement
749
750frerun-cse-after-loop
751Common Report Var(flag_rerun_cse_after_loop) Init(2)
752Add a common subexpression elimination pass after loop optimizations
753
754frerun-loop-opt
755Common
756Does nothing.  Preserved for backward compatibility.
757
758frounding-math
759Common Report Var(flag_rounding_math)
760Disable optimizations that assume default FP rounding behavior
761
762fsched-interblock
763Common Report Var(flag_schedule_interblock) Init(1)
764Enable scheduling across basic blocks
765
766fsched-spec
767Common Report Var(flag_schedule_speculative) Init(1)
768Allow speculative motion of non-loads
769
770fsched-spec-load
771Common Report Var(flag_schedule_speculative_load)
772Allow speculative motion of some loads
773
774fsched-spec-load-dangerous
775Common Report Var(flag_schedule_speculative_load_dangerous)
776Allow speculative motion of more loads
777
778fsched-verbose=
779Common RejectNegative Joined
780-fsched-verbose=<number>	Set the verbosity level of the scheduler
781
782fsched2-use-superblocks
783Common Report Var(flag_sched2_use_superblocks)
784If scheduling post reload, do superblock scheduling
785
786fsched2-use-traces
787Common Report Var(flag_sched2_use_traces)
788If scheduling post reload, do trace scheduling
789
790fschedule-insns
791Common Report Var(flag_schedule_insns)
792Reschedule instructions before register allocation
793
794fschedule-insns2
795Common Report Var(flag_schedule_insns_after_reload)
796Reschedule instructions after register allocation
797
798; sched_stalled_insns means that insns can be moved prematurely from the queue
799; of stalled insns into the ready list.
800fsched-stalled-insns
801Common Report Var(flag_sched_stalled_insns)
802Allow premature scheduling of queued insns
803
804fsched-stalled-insns=
805Common RejectNegative Joined UInteger
806-fsched-stalled-insns=<number>	Set number of queued insns that can be prematurely scheduled
807
808; sched_stalled_insns_dep controls how many recently scheduled cycles will
809; be examined for a dependency on a stalled insn that is candidate for
810; premature removal from the queue of stalled insns into the ready list (has
811; an effect only if the flag 'sched_stalled_insns' is set).
812fsched-stalled-insns-dep
813Common Report Var(flag_sched_stalled_insns_dep,1) Init(1)
814Set dependence distance checking in premature scheduling of queued insns
815
816fsched-stalled-insns-dep=
817Common RejectNegative Joined UInteger
818-fsched-stalled-insns-dep=<number>	Set dependence distance checking in premature scheduling of queued insns
819
820fsection-anchors
821Common Report Var(flag_section_anchors)
822Access data in the same section from shared anchor points
823
824frtl-abstract-sequences
825Common Report Var(flag_rtl_seqabstr)
826Perform sequence abstraction optimization on RTL
827
828fsee
829Common Report Var(flag_see) Init(0)
830Eliminate redundant sign extensions using LCM.
831
832fshow-column
833Common C ObjC C++ ObjC++ Report Var(flag_show_column) Init(1)
834Show column numbers in diagnostics, when available.  Default on
835
836fsignaling-nans
837Common Report Var(flag_signaling_nans)
838Disable optimizations observable by IEEE signaling NaNs
839
840fsingle-precision-constant
841Common Report Var(flag_single_precision_constant)
842Convert floating point constants to single precision constants
843
844fsplit-ivs-in-unroller
845Common Report Var(flag_split_ivs_in_unroller) Init(1)
846Split lifetimes of induction variables when loops are unrolled
847
848fvariable-expansion-in-unroller
849Common Report Var(flag_variable_expansion_in_unroller)
850Apply variable expansion when loops are unrolled
851
852; Emit code to probe the stack, to help detect stack overflow; also
853; may cause large objects to be allocated dynamically.
854fstack-check
855Common Report Var(flag_stack_check)
856Insert stack checking code into the program
857
858fstack-limit
859Common
860
861fstack-limit-register=
862Common RejectNegative Joined
863-fstack-limit-register=<register>	Trap if the stack goes past <register>
864
865fstack-limit-symbol=
866Common RejectNegative Joined
867-fstack-limit-symbol=<name>	Trap if the stack goes past symbol <name>
868
869fstack-protector
870Common Report Var(flag_stack_protect, 3) Init(-1)
871Use propolice as a stack protection method
872
873fstack-protector-all
874Common Report RejectNegative Var(flag_stack_protect, 2) VarExists
875Use a stack protection method for every function
876
877fstack-protector-strong
878Common Report RejectNegative Var(flag_stack_protect, 3)
879Use a smart stack protection method for certain functions
880
881fstack-shuffle
882Common Report Var(flag_stack_shuffle)
883Shuffle local stack variables.
884
885fstrength-reduce
886Common
887Does nothing.  Preserved for backward compatibility.
888
889; Nonzero if we should do (language-dependent) alias analysis.
890; Typically, this analysis will assume that expressions of certain
891; types do not alias expressions of certain other types.  Only used
892; if alias analysis (in general) is enabled.
893fstrict-aliasing
894Common Report Var(flag_strict_aliasing)
895Assume strict aliasing rules apply
896
897fstrict-overflow
898Common Report Var(flag_strict_overflow)
899Treat signed overflow as undefined
900
901fsyntax-only
902Common Report Var(flag_syntax_only)
903Check for syntax errors, then stop
904
905ftest-coverage
906Common Report Var(flag_test_coverage)
907Create data files needed by \"gcov\"
908
909fthread-jumps
910Common Report Var(flag_thread_jumps)
911Perform jump threading optimizations
912
913ftime-report
914Common Report Var(time_report)
915Report the time taken by each compiler pass
916
917ftls-model=
918Common Joined RejectNegative
919-ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec]	Set the default thread-local storage code generation model
920
921ftoplevel-reorder
922Common Report Var(flag_toplevel_reorder) Init(1)
923Reorder top level functions, variables, and asms
924
925ftracer
926Common Report Var(flag_tracer)
927Perform superblock formation via tail duplication
928
929; Zero means that floating-point math operations cannot generate a
930; (user-visible) trap.  This is the case, for example, in nonstop
931; IEEE 754 arithmetic.
932ftrapping-math
933Common Report Var(flag_trapping_math) Init(1)
934Assume floating-point operations can trap
935
936ftrapv
937Common Report Var(flag_trapv)
938Trap for signed overflow in addition, subtraction and multiplication
939
940ftree-ccp
941Common Report Var(flag_tree_ccp)
942Enable SSA-CCP optimization on trees
943
944ftree-store-ccp
945Common Report Var(flag_tree_store_ccp)
946Enable SSA-CCP optimization for stores and loads
947
948ftree-ch
949Common Report Var(flag_tree_ch)
950Enable loop header copying on trees
951
952ftree-combine-temps
953Common Report Var(flag_tree_combine_temps)
954Coalesce memory temporaries in the SSA->normal pass
955
956ftree-copyrename
957Common Report Var(flag_tree_copyrename)
958Replace SSA temporaries with better names in copies
959
960ftree-copy-prop
961Common Report Var(flag_tree_copy_prop)
962Enable copy propagation on trees
963
964ftree-store-copy-prop
965Common Report Var(flag_tree_store_copy_prop)
966Enable copy propagation for stores and loads
967
968ftree-dce
969Common Report Var(flag_tree_dce)
970Enable SSA dead code elimination optimization on trees
971
972ftree-dominator-opts
973Common Report Var(flag_tree_dom)
974Enable dominator optimizations
975
976ftree-dse
977Common Report Var(flag_tree_dse)
978Enable dead store elimination
979
980ftree-fre
981Common Report Var(flag_tree_fre)
982Enable Full Redundancy Elimination (FRE) on trees
983
984ftree-loop-im
985Common Report Var(flag_tree_loop_im) Init(1)
986Enable loop invariant motion on trees
987
988ftree-loop-linear
989Common Report Var(flag_tree_loop_linear)
990Enable linear loop transforms on trees
991
992ftree-loop-ivcanon
993Common Report Var(flag_tree_loop_ivcanon) Init(1)
994Create canonical induction variables in loops
995
996ftree-loop-optimize
997Common Report Var(flag_tree_loop_optimize) Init(1)
998Enable loop optimizations on tree level
999
1000ftree-pre
1001Common Report Var(flag_tree_pre)
1002Enable SSA-PRE optimization on trees
1003
1004ftree-salias
1005Common Report Var(flag_tree_salias)
1006Perform structural alias analysis
1007
1008ftree-sink
1009Common Report Var(flag_tree_sink)
1010Enable SSA code sinking on trees
1011
1012ftree-sra
1013Common Report Var(flag_tree_sra)
1014Perform scalar replacement of aggregates
1015
1016ftree-ter
1017Common Report Var(flag_tree_ter)
1018Replace temporary expressions in the SSA->normal pass
1019
1020ftree-lrs
1021Common Report Var(flag_tree_live_range_split)
1022Perform live range splitting during the SSA->normal pass
1023
1024ftree-vrp
1025Common Report Var(flag_tree_vrp) Init(0)
1026Perform Value Range Propagation on trees
1027
1028funit-at-a-time
1029Common Report Var(flag_unit_at_a_time)
1030Compile whole compilation unit at a time
1031
1032funroll-loops
1033Common Report Var(flag_unroll_loops)
1034Perform loop unrolling when iteration count is known
1035
1036funroll-all-loops
1037Common Report Var(flag_unroll_all_loops)
1038Perform loop unrolling for all loops
1039
1040; Nonzero means that loop optimizer may assume that the induction variables
1041; that control loops do not overflow and that the loops with nontrivial
1042; exit condition are not infinite
1043funsafe-loop-optimizations
1044Common Report Var(flag_unsafe_loop_optimizations)
1045Allow loop optimizations to assume that the loops behave in normal way
1046
1047; Nonzero means that unsafe floating-point math optimizations are allowed
1048; for the sake of speed.  IEEE compliance is not guaranteed, and operations
1049; are allowed to assume that their arguments and results are "normal"
1050; (e.g., nonnegative for SQRT).
1051funsafe-math-optimizations
1052Common Report Var(flag_unsafe_math_optimizations)
1053Allow math optimizations that may violate IEEE or ISO standards
1054
1055funswitch-loops
1056Common Report Var(flag_unswitch_loops)
1057Perform loop unswitching
1058
1059funwind-tables
1060Common Report Var(flag_unwind_tables)
1061Just generate unwind tables for exception handling
1062
1063fvar-tracking
1064Common Report Var(flag_var_tracking) VarExists
1065Perform variable tracking
1066
1067ftree-vectorize
1068Common Report Var(flag_tree_vectorize)
1069Enable loop vectorization on trees
1070
1071ftree-vect-loop-version
1072Common Report Var(flag_tree_vect_loop_version) Init(1)
1073Enable loop versioning when doing loop vectorization on trees
1074
1075ftree-vectorizer-verbose=
1076Common RejectNegative Joined
1077-ftree-vectorizer-verbose=<number>	Set the verbosity level of the vectorizer
1078
1079; -fverbose-asm causes extra commentary information to be produced in
1080; the generated assembly code (to make it more readable).  This option
1081; is generally only of use to those who actually need to read the
1082; generated assembly code (perhaps while debugging the compiler itself).
1083; -fno-verbose-asm, the default, causes the extra information
1084; to not be added and is useful when comparing two assembler files.
1085fverbose-asm
1086Common Report Var(flag_verbose_asm)
1087Add extra commentary to assembler output
1088
1089fvisibility=
1090Common Joined RejectNegative
1091-fvisibility=[default|internal|hidden|protected]	Set the default symbol visibility
1092
1093
1094fvpt
1095Common Report Var(flag_value_profile_transformations)
1096Use expression value profiles in optimizations
1097
1098fweb
1099Common Report Var(flag_web) Init(2)
1100Construct webs and split unrelated uses of single variable
1101
1102fwhole-program
1103Common Report Var(flag_whole_program) Init(0)
1104Perform whole program optimizations
1105
1106fwrapv
1107Common Report Var(flag_wrapv)
1108Assume signed arithmetic overflow wraps around
1109
1110fzero-initialized-in-bss
1111Common Report Var(flag_zero_initialized_in_bss) Init(0)
1112Put zero initialized data in the bss section
1113
1114g
1115Common JoinedOrMissing
1116Generate debug information in default format
1117
1118gcoff
1119Common JoinedOrMissing Negative(gdwarf-2)
1120Generate debug information in COFF format
1121
1122gdwarf-2
1123Common JoinedOrMissing Negative(gstabs)
1124Generate debug information in DWARF v2 format
1125
1126ggdb
1127Common JoinedOrMissing
1128Generate debug information in default extended format
1129
1130gstabs
1131Common JoinedOrMissing Negative(gstabs+)
1132Generate debug information in STABS format
1133
1134gstabs+
1135Common JoinedOrMissing Negative(gvms)
1136Generate debug information in extended STABS format
1137
1138gvms
1139Common JoinedOrMissing Negative(gxcoff)
1140Generate debug information in VMS format
1141
1142gxcoff
1143Common JoinedOrMissing Negative(gxcoff+)
1144Generate debug information in XCOFF format
1145
1146gxcoff+
1147Common JoinedOrMissing Negative(gcoff)
1148Generate debug information in extended XCOFF format
1149
1150o
1151Common Joined Separate
1152-o <file>	Place output into <file>
1153
1154p
1155Common Var(profile_flag)
1156Enable function profiling
1157
1158pedantic
1159Common Var(pedantic)
1160Issue warnings needed for strict compliance to the standard
1161
1162pedantic-errors
1163Common
1164Like -pedantic but issue them as errors
1165
1166quiet
1167Common Var(quiet_flag)
1168Do not display functions compiled or elapsed time
1169
1170version
1171Common Var(version_flag)
1172Display the compiler's version
1173
1174w
1175Common Var(inhibit_warnings)
1176Suppress warnings
1177
1178; This comment is to ensure we retain the blank line above.
1179