hppa: Export main in pr104869.C on hpux
[official-gcc.git] / gcc / common.opt
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1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003-2023 Free Software Foundation, Inc.
5 ; This file is part of GCC.
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 3, or (at your option) any later
10 ; version.
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.
17 ; You should have received a copy of the GNU General Public License
18 ; along with GCC; see the file COPYING3.  If not see
19 ; <http://www.gnu.org/licenses/>.
21 ; See the GCC internals manual (options.texi) for a description of this file's format.
23 ; Please try to keep this file in ASCII collating order.
25 Variable
26 int target_flags
28 Variable
29 int optimize
31 Variable
32 int optimize_size
34 Variable
35 int optimize_debug
37 ; Not used directly to control optimizations, only to save -Ofast
38 ; setting for "optimize" attributes.
39 Variable
40 int optimize_fast
42 ; True if this is the lto front end.  This is used to disable gimple
43 ; generation and lowering passes that are normally run on the output
44 ; of a front end.  These passes must be bypassed for lto since they
45 ; have already been done before the gimple was written.
46 Variable
47 bool in_lto_p = false
49 ; This variable is set to non-0 only by LTO front-end.  1 indicates that
50 ; the output produced will be used for incremental linking (thus weak symbols
51 ; can still be bound) and 2 indicates that the IL is going to be linked and
52 ; and output to LTO object file.
53 Variable
54 enum incremental_link flag_incremental_link = INCREMENTAL_LINK_NONE
56 ; 0 means straightforward implementation of complex divide acceptable.
57 ; 1 means wide ranges of inputs must work for complex divide.
58 ; 2 means C99-like requirements for complex multiply and divide.
59 Variable
60 int flag_complex_method = 1
62 Variable
63 int flag_default_complex_method = 1
65 ; Language specific warning pass for unused results.
66 Variable
67 bool flag_warn_unused_result = false
69 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
70 Variable
71 int flag_generate_lto
73 ; Nonzero if we should write GIMPLE bytecode for offload compilation.
74 Variable
75 int flag_generate_offload = 0
77 ; Nonzero means we should be saving declaration info into a .X file.
78 Variable
79 int flag_gen_aux_info = 0
81 ; Nonzero if we are compiling code for a shared library, zero for
82 ; executable.
83 Variable
84 int flag_shlib
86 ; These three are really VEC(char_p,heap) *.
88 Variable
89 void *flag_instrument_functions_exclude_functions
91 Variable
92 void *flag_instrument_functions_exclude_files
94 Variable
95 void *flag_ignored_attributes
97 ; Generic structs (e.g. templates not explicitly specialized)
98 ; may not have a compilation unit associated with them, and so
99 ; may need to be treated differently from ordinary structs.
101 ; Structs only handled by reference (indirectly), will also usually
102 ; not need as much debugging information.
104 Variable
105 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
107 Variable
108 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
110 ; True if we should exit after parsing options.
111 Variable
112 bool exit_after_options
114 ; Type(s) of debugging information we are producing (if any).  See
115 ; flag-types.h for the definitions of the different possible types of
116 ; debugging information.
117 Variable
118 uint32_t write_symbols = NO_DEBUG
120 ; Level of debugging information we are producing.  See flag-types.h
121 ; for the definitions of the different possible levels.
122 Variable
123 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
125 ; Level of CTF debugging information we are producing.  See flag-types.h
126 ; for the definitions of the different possible levels.
127 Variable
128 enum ctf_debug_info_levels ctf_debug_info_level = CTFINFO_LEVEL_NONE
130 ; Original value of maximum field alignment in bytes, specified via
131 ; -fpack-struct=<value>.
132 Variable
133 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
135 ; Type of stack check.
136 Variable
137 enum stack_check_type flag_stack_check = NO_STACK_CHECK
139 ; True if stack usage information needs to be computed.
140 Variable
141 bool flag_stack_usage_info = false
143 ; -dA causes debug commentary information to be produced in
144 ; the generated assembly code (to make it more readable).  This option
145 ; is generally only of use to those who actually need to read the
146 ; generated assembly code (perhaps while debugging the compiler itself).
147 ; Currently, this switch is only used by dwarf2out.cc; however, it is intended
148 ; to be a catchall for printing debug information in the assembler file.
149 Variable
150 int flag_debug_asm
152 ; Balance between GNAT encodings and standard DWARF to emit.
153 Variable
154 enum dwarf_gnat_encodings gnat_encodings = DWARF_GNAT_ENCODINGS_DEFAULT
156 ; -dP causes the rtl to be emitted as a comment in assembly.
157 Variable
158 int flag_dump_rtl_in_asm
160 ; Whether -da was passed (used only in handle_common_deferred_options).
161 Variable
162 bool flag_dump_all_passed
164 ; Other flags saying which kinds of debugging dump have been requested.
166 Variable
167 int rtl_dump_and_exit
169 Variable
170 int flag_print_asm_name
172 ; Name of top-level original source file (what was input to cpp).
173 ; This comes from the #-command at the beginning of the actual input.
174 ; If there isn't any there, then this is the cc1 input file name.
175 Variable
176 const char *main_input_filename
178 ; Pointer to base name in main_input_filename, with directories and a
179 ; single final extension removed, and the length of this base
180 ; name.
182 Variable
183 const char *main_input_basename
185 Variable
186 int main_input_baselength
188 ; The base name used for auxiliary output files.
189 ; dump_base_name minus dump_base_ext.
191 Variable
192 const char *aux_base_name
194 ; Which options have been printed by --help.
195 Variable
196 char *help_printed
198 ; Which enums have been printed by --help.  0 = not printed, no
199 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
200 ; = printed.
201 Variable
202 char *help_enum_printed
204 ; The number of columns for --help output.
205 Variable
206 unsigned int help_columns
208 ; Whether this options structure has been through finish_options
209 Variable
210 bool flag_opts_finished
212 ; What the sanitizer should instrument
213 Variable
214 unsigned int flag_sanitize
216 ; What sanitizers should recover from errors
217 Variable
218 unsigned int flag_sanitize_recover = (SANITIZE_UNDEFINED | SANITIZE_UNDEFINED_NONDEFAULT | SANITIZE_KERNEL_ADDRESS | SANITIZE_KERNEL_HWADDRESS) & ~(SANITIZE_UNREACHABLE | SANITIZE_RETURN)
220 ; What sanitizers should use __builtin_trap () instead of runtime diagnostics
221 Variable
222 unsigned int flag_sanitize_trap
224 ; Flag whether a prefix has been added to dump_base_name
225 Variable
226 bool dump_base_name_prefixed = false
228 ; What subset of registers should be zeroed on function return
229 Variable
230 unsigned int flag_zero_call_used_regs
233 Driver
235 -assemble
236 Driver Alias(S)
238 -compile
239 Driver Alias(c)
241 -completion=
242 Common Driver Joined Undocumented
243 Provide bash completion for options starting with provided string.
245 -coverage
246 Driver Alias(coverage)
248 -debug
249 Common Alias(g)
251 -dump
252 Common Separate Alias(d)
254 -dump=
255 Common Joined Alias(d)
257 -dumpbase
258 Driver Common Separate Alias(dumpbase)
260 -dumpbase-ext
261 Driver Common Separate Alias(dumpbase-ext)
263 -dumpdir
264 Driver Common Separate Alias(dumpdir)
266 -entry
267 Driver Separate Alias(e)
269 -entry=
270 Driver Joined Alias(e)
272 -extra-warnings
273 Common Warning Alias(Wextra)
275 -for-assembler
276 Driver Separate Alias(Xassembler)
278 -for-assembler=
279 Driver JoinedOrMissing Alias(Xassembler)
281 -for-linker
282 Driver Separate Alias(Xlinker)
284 -for-linker=
285 Driver JoinedOrMissing Alias(Xlinker)
287 -force-link
288 Driver Separate Alias(u)
290 -force-link=
291 Driver Joined Alias(u)
293 -help
294 Common Driver Var(help_flag)
295 Display this information.
297 -help=
298 Common Driver Joined
299 --help=<class>  Display descriptions of a specific class of options.  <class> is one or more of optimizers, target, warnings, undocumented, params.
301 -language
302 Driver Separate Alias(x)
304 -language=
305 Driver Joined Alias(x)
307 -library-directory
308 Driver Separate Alias(L)
310 -library-directory=
311 Driver Joined Alias(L)
313 -no-canonical-prefixes
314 Driver Alias(no-canonical-prefixes)
316 -no-standard-libraries
317 Driver Alias(nostdlib)
319 -no-sysroot-suffix
320 Driver Var(no_sysroot_suffix)
322 -no-warnings
323 Common Alias(w)
325 -optimize
326 Common Alias(O)
328 -output
329 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
331 -output=
332 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
334 -pass-exit-codes
335 Driver Alias(pass-exit-codes)
337 -pedantic
338 Common Alias(Wpedantic)
340 -pedantic-errors
341 Common Alias(pedantic-errors)
343 -pie
344 Driver Alias(pie)
346 -static-pie
347 Driver Alias(static-pie)
349 -pipe
350 Driver Alias(pipe)
352 -prefix
353 Driver Separate Alias(B)
355 -prefix=
356 Driver JoinedOrMissing Alias(B)
358 -preprocess
359 Driver Alias(E)
361 -print-file-name
362 Driver Separate Alias(print-file-name=)
364 -print-file-name=
365 Driver JoinedOrMissing Alias(print-file-name=)
367 -print-libgcc-file-name
368 Driver Alias(print-libgcc-file-name)
370 -print-multi-directory
371 Driver Alias(print-multi-directory)
373 -print-multi-lib
374 Driver Alias(print-multi-lib)
376 -print-multi-os-directory
377 Driver Alias(print-multi-os-directory)
379 -print-multiarch
380 Driver Alias(print-multiarch)
382 -print-prog-name
383 Driver Separate Alias(print-prog-name=)
385 -print-prog-name=
386 Driver JoinedOrMissing Alias(print-prog-name=)
388 -print-search-dirs
389 Driver Alias(print-search-dirs)
391 -print-sysroot
392 Driver Alias(print-sysroot)
394 -print-sysroot-headers-suffix
395 Driver Alias(print-sysroot-headers-suffix)
397 -profile
398 Common Alias(p)
400 -save-temps
401 Driver Alias(save-temps)
403 -shared
404 Driver Alias(shared)
406 -specs
407 Driver Separate Alias(specs=)
409 -specs=
410 Driver Joined Alias(specs=)
412 -static
413 Driver Alias(static)
415 -symbolic
416 Driver Alias(symbolic)
418 -target-help
419 Common Driver
420 Display target specific command line options (including assembler and linker options).
422 -time
423 Driver Alias(time)
425 -verbose
426 Driver Alias(v)
428 ;; The driver used to convert options such as --help into forms such
429 ;; as -fhelp; the following four entries are for compatibility with
430 ;; any direct uses of those (undocumented) -f forms
431 fhelp
432 Common Driver Alias(-help)
434 fhelp=
435 Common Driver Joined Alias(-help=)
437 ftarget-help
438 Common Driver Alias(-target-help)
440 fversion
441 Common Driver Alias(-version)
443 -sysroot
444 Driver Separate Alias(-sysroot=)
446 -sysroot=
447 Driver JoinedOrMissing
449 -version
450 Common Driver
453 Driver Joined Separate
456 Driver
459 Driver Joined Separate
462 Driver
465 Common JoinedOrMissing Optimization
466 -O<number>      Set optimization level to <number>.
469 Common Optimization
470 Optimize for space rather than speed.
472 Ofast
473 Common Optimization
474 Optimize for speed disregarding exact standards compliance.
477 Common Optimization
478 Optimize for debugging experience rather than speed or size.
481 Common Optimization
482 Optimize for space aggressively rather than speed.
485 Driver
488 Driver Negative(Qy)
491 Driver Negative(Qn)
494 Driver Joined Separate
497 Driver
500 Driver Joined Separate
502 Tbss
503 Driver Separate
505 Tbss=
506 Driver Joined
508 Tdata
509 Driver Separate
511 Tdata=
512 Driver Joined
514 Ttext
515 Driver Separate
517 Ttext=
518 Driver Joined
521 Common RejectNegative Warning Alias(Wextra)
522 This switch is deprecated; use -Wextra instead.
525 Driver JoinedOrMissing RejectNegative
528 Driver JoinedOrMissing RejectNegative
531 Driver JoinedOrMissing RejectNegative
533 Waggregate-return
534 Common Var(warn_aggregate_return) Warning
535 Warn about returning structures, unions or arrays.
537 Waggressive-loop-optimizations
538 Common Var(warn_aggressive_loop_optimizations) Init(1) Warning
539 Warn if a loop with constant number of iterations triggers undefined behavior.
541 Warray-bounds
542 Common Alias(Warray-bounds=, 1, 0) Warning
544 Warray-bounds=
545 Common Joined RejectNegative UInteger Var(warn_array_bounds) Warning IntegerRange(0, 2)
546 Warn if an array is accessed out of bounds.
548 Wuse-after-free
549 Common Var(warn_use_after_free) Warning
550 Warn for uses of pointers to deallocated storage.
552 Wuse-after-free=
553 Common Joined RejectNegative UInteger Var(warn_use_after_free) Warning IntegerRange(0, 3)
554 Warn for uses of pointers to deallocated storage.
556 Wattributes
557 Common Var(warn_attributes) Init(1) Warning
558 Warn about inappropriate attribute usage.
560 Wattributes=
561 Common Joined
562 Do not warn about specified attributes.
564 Wattribute-alias
565 Common Alias(Wattribute_alias=, 1, 0) Warning
566 Warn about type safety and similar errors and mismatches in declarations with alias attributes.
568 Wattribute-alias=
569 Common Joined RejectNegative UInteger Var(warn_attribute_alias) Init(1) Warning IntegerRange(0, 2)
570 Warn about type safety and similar errors and mismatches in declarations with alias attributes.
572 Wcannot-profile
573 Common Var(warn_cannot_profile) Init(1) Warning
574 Warn when profiling instrumentation was requested, but could not be applied to
575 a certain function.
577 Wcast-align
578 Common Var(warn_cast_align) Warning
579 Warn about pointer casts which increase alignment.
581 Wcast-align=strict
582 Common Var(warn_cast_align,2) Warning
583 Warn about pointer casts which increase alignment.
585 Wcomplain-wrong-lang
586 Common Var(warn_complain_wrong_lang) Init(1) Warning
587 Complain when a command-line option is valid, but not applicable to the current front end.
589 Wcpp
590 Common Var(warn_cpp) Init(1) Warning
591 Warn when a #warning directive is encountered.
593 Wattribute-warning
594 Common Var(warn_attribute_warning) Init(1) Warning
595 Warn about uses of __attribute__((warning)) declarations.
597 Wdeprecated
598 Common Var(warn_deprecated) Init(1) Warning
599 Warn if a deprecated compiler feature, class, method, or field is used.
601 Wdeprecated-declarations
602 Common Var(warn_deprecated_decl) Init(1) Warning
603 Warn about uses of __attribute__((deprecated)) declarations.
605 Wdisabled-optimization
606 Common Var(warn_disabled_optimization) Warning
607 Warn when an optimization pass is disabled.
609 Werror
610 Common Var(warnings_are_errors)
611 Treat all warnings as errors.
613 Werror=
614 Common Joined
615 Treat specified warning as error.
617 Wextra
618 Common Var(extra_warnings) Warning
619 Print extra (possibly unwanted) warnings.
621 Wfatal-errors
622 Common Var(flag_fatal_errors)
623 Exit on the first error occurred.
625 Wframe-larger-than=
626 Common RejectNegative Joined Host_Wide_Int ByteSize Warning Var(warn_frame_larger_than_size) Init(HOST_WIDE_INT_MAX)
627 -Wframe-larger-than=<byte-size> Warn if a function's stack frame requires in excess of <byte-size>.
629 Wno-frame-larger-than
630 Common Alias(Wframe-larger-than=,18446744073709551615EiB,none) Warning
631 Disable -Wframe-larger-than= warning.  Equivalent to -Wframe-larger-than=<SIZE_MAX> or larger.
633 Wfree-nonheap-object
634 Common Var(warn_free_nonheap_object) Init(1) Warning
635 Warn when attempting to free a non-heap object.
637 Whardened
638 Common Var(warn_hardened) Init(1) Warning
639 Warn when -fhardened did not enable an option from its set.
641 Whsa
642 Common Ignore Warning
643 Does nothing.  Preserved for backward compatibility.
645 Wimplicit-fallthrough
646 Common Alias(Wimplicit-fallthrough=,3,0) Warning
648 Wimplicit-fallthrough=
649 Common Var(warn_implicit_fallthrough) RejectNegative Joined UInteger Warning IntegerRange(0, 5)
650 Warn when a switch case falls through.
652 Winfinite-recursion
653 Var(warn_infinite_recursion) Warning
654 Warn for infinitely recursive calls.
656 Winline
657 Common Var(warn_inline) Warning Optimization
658 Warn when an inlined function cannot be inlined.
660 Winvalid-memory-model
661 Common Var(warn_invalid_memory_model) Init(1) Warning
662 Warn when an atomic memory model parameter is known to be outside the valid range.
664 Wlarger-than-
665 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
667 Wlarger-than=
668 Common RejectNegative Joined Host_Wide_Int ByteSize Warning Var(warn_larger_than_size) Init(HOST_WIDE_INT_MAX)
669 -Wlarger-than=<byte-size>       Warn if an object's size exceeds <byte-size>.
671 Wno-larger-than
672 Common Alias(Wlarger-than=,18446744073709551615EiB,none) Warning
673 Disable -Wlarger-than= warning.  Equivalent to -Wlarger-than=<SIZE_MAX> or larger.
675 Wnonnull-compare
676 Var(warn_nonnull_compare) Warning
677 Warn if comparing pointer parameter with nonnull attribute with NULL.
679 Wnull-dereference
680 Common Var(warn_null_dereference) Warning
681 Warn if dereferencing a NULL pointer may lead to erroneous or undefined behavior.
683 Wunsafe-loop-optimizations
684 Common Ignore Warning
685 Does nothing. Preserved for backward compatibility.
687 Wmissing-noreturn
688 Common Warning Alias(Wsuggest-attribute=noreturn)
690 Wodr
691 Common Var(warn_odr_violations) Init(1) Warning
692 Warn about some C++ One Definition Rule violations during link time optimization.
694 Woverflow
695 Common Var(warn_overflow) Init(1) Warning
696 Warn about overflow in arithmetic expressions.
698 Wlto-type-mismatch
699 Common Var(warn_lto_type_mismatch) Init(1) Warning
700 During link time optimization warn about mismatched types of global declarations.
702 Wpacked
703 Common Var(warn_packed) Warning
704 Warn when the packed attribute has no effect on struct layout.
706 Wpadded
707 Common Var(warn_padded) Warning
708 Warn when padding is required to align structure members.
710 Wpedantic
711 Common Var(pedantic) Init(0) Warning
712 Issue warnings needed for strict compliance to the standard.
714 Wreturn-local-addr
715 Common Var(warn_return_local_addr) Init(1) Warning
716 Warn about returning a pointer/reference to a local or temporary variable.
718 Wshadow
719 Common Var(warn_shadow) Warning
720 Warn when one variable shadows another.  Same as -Wshadow=global.
722 Wshadow=global
723 Common Warning Alias(Wshadow)
724 Warn when one variable shadows another (globally).
726 Wshadow=local
727 Common Var(warn_shadow_local) Warning EnabledBy(Wshadow)
728 Warn when one local variable shadows another local variable or parameter.
730 Wshadow-local
731 Common Warning Undocumented Alias(Wshadow=local)
733 Wshadow=compatible-local
734 Common Var(warn_shadow_compatible_local) Warning EnabledBy(Wshadow=local)
735 Warn when one local variable shadows another local variable or parameter of compatible type.
737 Wshadow-compatible-local
738 Common Warning Undocumented Alias(Wshadow=compatible-local)
740 Wstack-protector
741 Common Var(warn_stack_protect) Warning
742 Warn when not issuing stack smashing protection for some reason.
744 Wstack-usage=
745 Common Joined RejectNegative Host_Wide_Int ByteSize Var(warn_stack_usage) Warning Init(HOST_WIDE_INT_MAX)
746 -Wstack-usage=<byte-size>       Warn if stack usage might exceed <byte-size>.
748 Wno-stack-usage
749 Common Alias(Wstack-usage=,18446744073709551615EiB,none) Warning
750 Disable Wstack-usage= warning.  Equivalent to Wstack-usage=<SIZE_MAX> or larger.
752 Wstrict-aliasing
753 Common Warning
754 Warn about code which might break strict aliasing rules.
756 Wstrict-aliasing=
757 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
758 Warn about code which might break strict aliasing rules.
760 Wstrict-overflow
761 Common Warning
762 Warn about optimizations that assume that signed overflow is undefined.
764 Wstrict-overflow=
765 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
766 Warn about optimizations that assume that signed overflow is undefined.
768 Wsuggest-attribute=cold
769 Common Var(warn_suggest_attribute_cold) Warning
770 Warn about functions which might be candidates for __attribute__((cold)).
772 Wsuggest-attribute=const
773 Common Var(warn_suggest_attribute_const) Warning
774 Warn about functions which might be candidates for __attribute__((const)).
776 Wsuggest-attribute=pure
777 Common Var(warn_suggest_attribute_pure) Warning
778 Warn about functions which might be candidates for __attribute__((pure)).
780 Wsuggest-attribute=noreturn
781 Common Var(warn_suggest_attribute_noreturn) Warning
782 Warn about functions which might be candidates for __attribute__((noreturn)).
784 Wsuggest-attribute=malloc
785 Common Var(warn_suggest_attribute_malloc) Warning
786 Warn about functions which might be candidates for __attribute__((malloc)).
788 Wsuggest-attribute=returns_nonnull
789 Common Var(warn_suggest_attribute_returns_nonnull) Warning
790 Warn about functions which might be candidates for __attribute__((returns_nonnull)).
792 Wsuggest-final-types
793 Common Var(warn_suggest_final_types) Warning
794 Warn about C++ polymorphic types where adding final keyword would improve code quality.
796 Wsuggest-final-methods
797 Common Var(warn_suggest_final_methods) Warning
798 Warn about C++ virtual methods where adding final keyword would improve code quality.
800 Wswitch-unreachable
801 Common Var(warn_switch_unreachable) Warning Init(1)
802 Warn about statements between switch's controlling expression and the first
803 case.
805 Wsystem-headers
806 Common Var(warn_system_headers) Warning
807 Do not suppress warnings from system headers.
809 Wtrampolines
810 Common Var(warn_trampolines) Warning
811 Warn whenever a trampoline is generated.
813 Wtrivial-auto-var-init
814 Common Var(warn_trivial_auto_var_init) Warning Init(0)
815 Warn about cases where -ftrivial-auto-var-init cannot initialize an auto variable.
817 Wtype-limits
818 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
819 Warn if a comparison is always true or always false due to the limited range of the data type.
821 Wuninitialized
822 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
823 Warn about uninitialized automatic variables.
825 Wmaybe-uninitialized
826 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
827 Warn about maybe uninitialized automatic variables.
829 Wunreachable-code
830 Common Ignore Warning
831 Does nothing. Preserved for backward compatibility.
833 Wunused
834 Common Var(warn_unused) Init(0) Warning
835 Enable all -Wunused- warnings.
837 Wunused-but-set-parameter
838 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
839 Warn when a function parameter is only set, otherwise unused.
841 Wunused-but-set-variable
842 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
843 Warn when a variable is only set, otherwise unused.
845 Wunused-function
846 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
847 Warn when a function is unused.
849 Wunused-label
850 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
851 Warn when a label is unused.
853 Wunused-parameter
854 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
855 Warn when a function parameter is unused.
857 Wunused-value
858 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
859 Warn when an expression value is unused.
861 Wunused-variable
862 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
863 Warn when a variable is unused.
865 Wcoverage-mismatch
866 Common Var(warn_coverage_mismatch) Init(1) Warning
867 Warn in case profiles in -fprofile-use do not match.
869 Wcoverage-invalid-line-number
870 Common Var(warn_coverage_invalid_linenum) Init(1) Warning
871 Warn in case a function ends earlier than it begins due to an invalid linenum macros.
873 Wmissing-profile
874 Common Var(warn_missing_profile) Init(1) Warning
875 Warn in case profiles in -fprofile-use do not exist.
877 Wvector-operation-performance
878 Common Var(warn_vector_operation_performance) Warning
879 Warn when a vector operation is compiled outside the SIMD.
881 Wtsan
882 Common Var(warn_tsan) Init(1) Warning
883 Warn about unsupported features in ThreadSanitizer.
885 Xassembler
886 Driver Separate
888 Xlinker
889 Driver Separate
891 Xpreprocessor
892 Driver Separate
895 Driver
897 aux-info
898 Common Separate Var(aux_info_file_name)
899 -aux-info <file>        Emit declaration information into <file>.
901 aux-info=
902 Common Joined Alias(aux-info)
904 coverage
905 Driver
908 Driver
911 Common Joined
912 -d<letters>     Enable dumps from specific passes of the compiler.
914 dumpbase
915 Driver Common Separate Var(dump_base_name)
916 -dumpbase <file>        Set the file basename to be used for dumps.
918 dumpbase-ext
919 Driver Common Separate Var(dump_base_ext)
920 -dumpbase-ext .<ext>    Drop a trailing .<ext> from the dump basename to name auxiliary output files.
922 dumpdir
923 Driver Common Separate Var(dump_dir_name)
924 -dumpdir <dir>  Set the directory name to be used for dumps.
926 dumpmachine
927 Driver
929 dumpspecs
930 Driver
932 dumpversion
933 Driver
935 dumpfullversion
936 Driver
939 Driver Joined Separate
941 ; This option has historically been passed down to the linker by an
942 ; accident of a %{e*} spec, so ensure it continues to be passed down
943 ; as a single option.  The supported option for this purpose is
944 ; -rdynamic.  See PR 47390.
945 export-dynamic
946 Driver Undocumented
948 ; The version of the C++ ABI in use.  The following values are allowed:
950 ; 0: The version of the ABI believed most conformant with the C++ ABI
951 ;    specification.  This ABI may change as bugs are discovered and fixed.
952 ;    Therefore, 0 will not necessarily indicate the same ABI in different
953 ;    versions of G++.
955 ; 1: The version of the ABI first used in G++ 3.2.  No longer selectable.
957 ; 2: The version of the ABI first used in G++ 3.4, and the default
958 ;    until GCC 4.9.
960 ; 3: The version of the ABI that fixes the missing underscore
961 ;    in template non-type arguments of pointer type.
963 ; 4: The version of the ABI that introduces unambiguous mangling of
964 ;    vector types.  First selectable in G++ 4.5.
966 ; 5: The version of the ABI that ignores attribute const/noreturn
967 ;    in function pointer mangling, and corrects mangling of decltype and
968 ;    function parameters used in other parameters and the return type.
969 ;    First selectable in G++ 4.6.
971 ; 6: The version of the ABI that doesn't promote scoped enums to int and
972 ;    changes the mangling of template argument packs, const/static_cast,
973 ;    prefix ++ and --, and a class scope function used as a template
974 ;    argument.
975 ;    First selectable in G++ 4.7.
977 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
978 ;    corrects the mangling of lambdas in default argument scope.
979 ;    First selectable in G++ 4.8.
981 ; 8: The version of the ABI that corrects the substitution behavior of
982 ;    function types with function-cv-qualifiers.
983 ;    First selectable in G++ 4.9 and default in G++ 5.
985 ; 9: The version of the ABI that corrects the alignment of nullptr_t.
986 ;    First selectable and default in G++ 5.2.
988 ; 10: The version of the ABI that mangles attributes that affect type
989 ;     identity, such as ia32 calling convention attributes (stdcall, etc.)
990 ;     Default in G++ 6 (set in c_common_post_options).
992 ; 11: The version of the ABI that corrects mangling of sizeof... expressions
993 ;     and introduces new inheriting constructor handling.
994 ;     Default in G++ 7.
996 ; 12: Corrects the calling convention for classes with only deleted copy/move
997 ;     constructors and changes passing/returning of empty records.
998 ;     Default in G++ 8.1.
1000 ; 13: Fixes the accidental change in 12 to the calling convention for classes
1001 ;     with deleted copy constructor and trivial move constructor.
1002 ;     Default in G++ 8.2.
1004 ; 14: Corrects the mangling of nullptr expression.
1005 ;     Default in G++ 10.
1007 ; 15: Corrects G++ 10 ABI tag regression [PR98481].
1008 ;     Available, but not default, in G++ 10.3.
1010 ; 16: Changes the mangling of __alignof__ to be distinct from that of alignof.
1011 ;     Adds missing 'on' in mangling of operator names in some cases.
1012 ;     Default in G++ 11.
1014 ; 17: Fixes layout of classes that inherit from aggregate classes with default
1015 ;     member initializers in C++14 and up.
1016 ;     Default in G++ 12.
1018 ; 18: Corrects errors in mangling of lambdas with additional context.
1019 ;     Default in G++ 13.
1021 ; 19: Emits ABI tags if needed in structured binding mangled names.
1022 ;     Ignores cv-quals on [[no_unique_object]] members.
1023 ;     Default in G++ 14.
1025 ; Additional positive integers will be assigned as new versions of
1026 ; the ABI become the default version of the ABI.
1027 fabi-version=
1028 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(0)
1029 The version of the C++ ABI in use.
1031 faggressive-loop-optimizations
1032 Common Var(flag_aggressive_loop_optimizations) Optimization Init(1)
1033 Aggressively optimize loops using language constraints.
1035 falign-functions
1036 Common Var(flag_align_functions) Optimization
1037 Align the start of functions.
1039 falign-functions=
1040 Common RejectNegative Joined Var(str_align_functions) Optimization
1042 flimit-function-alignment
1043 Common Var(flag_limit_function_alignment) Optimization Init(0)
1045 falign-jumps
1046 Common Var(flag_align_jumps) Optimization
1047 Align labels which are only reached by jumping.
1049 falign-jumps=
1050 Common RejectNegative Joined Var(str_align_jumps) Optimization
1052 falign-labels
1053 Common Var(flag_align_labels) Optimization
1054 Align all labels.
1056 falign-labels=
1057 Common RejectNegative Joined Var(str_align_labels) Optimization
1059 falign-loops
1060 Common Var(flag_align_loops) Optimization
1061 Align the start of loops.
1063 falign-loops=
1064 Common RejectNegative Joined Var(str_align_loops) Optimization
1066 fallow-store-data-races
1067 Common Var(flag_store_data_races) Optimization
1068 Allow the compiler to introduce new data races on stores.
1070 fanalyzer
1071 Common Var(flag_analyzer)
1072 Enable static analysis pass.
1074 fargument-alias
1075 Common Ignore
1076 Does nothing. Preserved for backward compatibility.
1078 fargument-noalias
1079 Common Ignore
1080 Does nothing. Preserved for backward compatibility.
1082 fargument-noalias-global
1083 Common Ignore
1084 Does nothing. Preserved for backward compatibility.
1086 fargument-noalias-anything
1087 Common Ignore
1088 Does nothing. Preserved for backward compatibility.
1090 fsanitize=
1091 Common Driver Joined
1092 Select what to sanitize.
1094 fsanitize-coverage=
1095 Common Joined Enum(sanitize_coverage) Var(flag_sanitize_coverage) EnumBitSet
1096 Select type of coverage sanitization.
1098 Enum
1099 Name(sanitize_coverage) Type(int)
1101 EnumValue
1102 Enum(sanitize_coverage) String(trace-pc) Value(SANITIZE_COV_TRACE_PC)
1104 EnumValue
1105 Enum(sanitize_coverage) String(trace-cmp) Value(SANITIZE_COV_TRACE_CMP)
1107 fasan-shadow-offset=
1108 Common Joined RejectNegative Var(common_deferred_options) Defer
1109 -fasan-shadow-offset=<number>   Use custom shadow memory offset.
1111 fsanitize-sections=
1112 Common Joined RejectNegative Var(common_deferred_options) Defer
1113 -fsanitize-sections=<sec1,sec2,...>     Sanitize global variables
1114 in user-defined sections.
1116 fsanitize-recover=
1117 Common Joined
1118 After diagnosing undefined behavior attempt to continue execution.
1120 fsanitize-recover
1121 Common
1122 This switch is deprecated; use -fsanitize-recover= instead.
1124 fsanitize-trap=
1125 Common Driver Joined
1126 Use traps instead of diagnostics of undefined behavior sanitizers.
1128 fsanitize-trap
1129 Common Driver
1131 fsanitize-address-use-after-scope
1132 Common Driver Var(flag_sanitize_address_use_after_scope) Init(0)
1134 fsanitize-undefined-trap-on-error
1135 Common Driver Alias(fsanitize-trap)
1136 This switch is deprecated; use -fsanitize-trap= instead.
1138 fasynchronous-unwind-tables
1139 Common Var(flag_asynchronous_unwind_tables) Optimization
1140 Generate unwind tables that are exact at each instruction boundary.
1142 fauto-inc-dec
1143 Common Var(flag_auto_inc_dec) Init(1) Optimization
1144 Generate auto-inc/dec instructions.
1146 fauto-profile
1147 Common Var(flag_auto_profile)
1148 Use sample profile information for call graph node weights. The default
1149 profile file is fbdata.afdo in 'pwd'.
1151 fauto-profile=
1152 Common Joined RejectNegative Var(auto_profile_file)
1153 Use sample profile information for call graph node weights. The profile
1154 file is specified in the argument.
1156 ; -fcheck-bounds causes gcc to generate array bounds checks.
1157 ; For C, C++ and ObjC: defaults off.
1158 ; For Java: defaults to on.
1159 ; For Fortran: defaults to off.
1160 fbounds-check
1161 Common Var(flag_bounds_check)
1162 Generate code to check bounds before indexing arrays.
1164 fbranch-count-reg
1165 Common Var(flag_branch_on_count_reg) Optimization
1166 Replace add, compare, branch with branch on count register.
1168 fbranch-probabilities
1169 Common Var(flag_branch_probabilities) Optimization
1170 Use profiling information for branch probabilities.
1172 fbranch-target-load-optimize
1173 Common Ignore
1174 Does nothing.  Preserved for backward compatibility.
1176 fbranch-target-load-optimize2
1177 Common Ignore
1178 Does nothing.  Preserved for backward compatibility.
1180 fbtr-bb-exclusive
1181 Common Ignore
1182 Does nothing.  Preserved for backward compatibility.
1184 fcallgraph-info
1185 Common RejectNegative Var(flag_callgraph_info) Init(NO_CALLGRAPH_INFO);
1186 Output callgraph information on a per-file basis.
1188 fcallgraph-info=
1189 Common RejectNegative Joined
1190 Output callgraph information on a per-file basis with decorations.
1192 fcall-saved-
1193 Common Joined RejectNegative Var(common_deferred_options) Defer
1194 -fcall-saved-<register> Mark <register> as being preserved across functions.
1196 fcall-used-
1197 Common Joined RejectNegative Var(common_deferred_options) Defer
1198 -fcall-used-<register>  Mark <register> as being corrupted by function calls.
1200 ; Nonzero for -fcaller-saves: allocate values in regs that need to
1201 ; be saved across function calls, if that produces overall better code.
1202 ; Optional now, so people can test it.
1203 fcaller-saves
1204 Common Var(flag_caller_saves) Optimization
1205 Save registers around function calls.
1207 fcheck-data-deps
1208 Common Ignore
1209 This switch is deprecated; do not use.
1211 fcheck-new
1212 Common Var(flag_check_new)
1213 Check the return value of new in C++.
1215 fchecking
1216 Common Var(flag_checking) Init(CHECKING_P ? ENABLE_EXTRA_CHECKING ? 2 : 1 : 0)
1217 Perform internal consistency checkings.
1219 fchecking=
1220 Common Joined RejectNegative UInteger Var(flag_checking)
1221 Perform internal consistency checkings.
1223 fcanon-prefix-map
1224 Common Var(common_deferred_options) Defer
1225 For -f*-prefix-map= options compare canonicalized pathnames rather than just strings.
1227 fcode-hoisting
1228 Common Var(flag_code_hoisting) Optimization
1229 Enable code hoisting.
1231 fcombine-stack-adjustments
1232 Common Var(flag_combine_stack_adjustments) Optimization
1233 Looks for opportunities to reduce stack adjustments and stack references.
1235 fcommon
1236 Common Var(flag_no_common,0) Init(1)
1237 Put uninitialized globals in the common section.
1239 fcompare-debug
1240 Driver
1241 ; Converted by the driver to -fcompare-debug= options.
1243 fcompare-debug=
1244 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
1245 -fcompare-debug[=<opts>]        Compile with and without e.g. -gtoggle, and compare the final-insns dump.
1247 fcompare-debug-second
1248 Common Driver RejectNegative Var(flag_compare_debug)
1249 Run only the second compilation of -fcompare-debug.
1251 fcompare-elim
1252 Common Var(flag_compare_elim_after_reload) Optimization
1253 Perform comparison elimination after register allocation has finished.
1255 fconserve-stack
1256 Common Var(flag_conserve_stack) Optimization
1257 Do not perform optimizations increasing noticeably stack usage.
1259 fcprop-registers
1260 Common Var(flag_cprop_registers) Optimization
1261 Perform a register copy-propagation optimization pass.
1263 ffold-mem-offsets
1264 Target Bool Var(flag_fold_mem_offsets) Init(1)
1265 Fold instructions calculating memory offsets to the memory access instruction if possible.
1267 fcrossjumping
1268 Common Var(flag_crossjumping) Optimization
1269 Perform cross-jumping optimization.
1271 fcse-follow-jumps
1272 Common Var(flag_cse_follow_jumps) Optimization
1273 When running CSE, follow jumps to their targets.
1275 fcse-skip-blocks
1276 Common Ignore
1277 Does nothing.  Preserved for backward compatibility.
1279 fcx-limited-range
1280 Common Var(flag_cx_limited_range) Optimization SetByCombined
1281 Omit range reduction step when performing complex division.
1283 fcx-fortran-rules
1284 Common Var(flag_cx_fortran_rules) Optimization
1285 Complex multiplication and division follow Fortran rules.
1287 fdata-sections
1288 Common Var(flag_data_sections)
1289 Place data items into their own section.
1291 fdbg-cnt-list
1292 Common Var(flag_dbg_cnt_list)
1293 List all available debugging counters with their limits and counts.
1295 fdbg-cnt=
1296 Common RejectNegative Joined Var(common_deferred_options) Defer
1297 -fdbg-cnt=<counter>[:<lower_limit1>-]<upper_limit1>[:<lower_limit2>-<upper_limit2>:...][,<counter>:...] Set the debug counter limit.
1299 fdebug-prefix-map=
1300 Common Joined RejectNegative Var(common_deferred_options) Defer
1301 -fdebug-prefix-map=<old>=<new>  Map one directory name to another in debug information.
1303 ffile-prefix-map=
1304 Common Joined RejectNegative Var(common_deferred_options) Defer
1305 -ffile-prefix-map=<old>=<new>   Map one directory name to another in compilation result.
1307 fdebug-types-section
1308 Common Var(flag_debug_types_section) Init(0)
1309 Output .debug_types section when using DWARF v4 debuginfo.
1311 ; Nonzero for -fdefer-pop: don't pop args after each function call
1312 ; instead save them up to pop many calls' args with one insns.
1313 fdefer-pop
1314 Common Var(flag_defer_pop) Optimization
1315 Defer popping functions args from stack until later.
1317 fdelayed-branch
1318 Common Var(flag_delayed_branch) Optimization
1319 Attempt to fill delay slots of branch instructions.
1321 fdelete-dead-exceptions
1322 Common Var(flag_delete_dead_exceptions) Init(0) Optimization
1323 Delete dead instructions that may throw exceptions.
1325 fdelete-null-pointer-checks
1326 Common Var(flag_delete_null_pointer_checks) Init(-1) Optimization
1327 Delete useless null pointer checks.
1329 fdevirtualize-at-ltrans
1330 Common Var(flag_ltrans_devirtualize)
1331 Stream extra data to support more aggressive devirtualization in LTO local transformation mode.
1333 fdevirtualize-speculatively
1334 Common Var(flag_devirtualize_speculatively) Optimization
1335 Perform speculative devirtualization.
1337 fdevirtualize
1338 Common Var(flag_devirtualize) Optimization
1339 Try to convert virtual calls to direct ones.
1341 fdiagnostics-show-location=
1342 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1343 -fdiagnostics-show-location=[once|every-line]   How often to emit source location at the beginning of line-wrapped diagnostics.
1345 ; Required for these enum values.
1346 SourceInclude
1347 pretty-print.h
1349 Enum
1350 Name(diagnostic_prefixing_rule) Type(int)
1352 EnumValue
1353 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1355 EnumValue
1356 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1358 fdiagnostics-show-caret
1359 Common Var(flag_diagnostics_show_caret) Init(1)
1360 Show the source line with a caret indicating the column.
1362 fdiagnostics-show-labels
1363 Common Var(flag_diagnostics_show_labels) Init(1)
1364 Show labels annotating ranges of source code when showing source.
1366 fdiagnostics-show-line-numbers
1367 Common Var(flag_diagnostics_show_line_numbers) Init(1)
1368 Show line numbers in the left margin when showing source.
1370 fdiagnostics-color
1371 Common Alias(fdiagnostics-color=,always,never)
1374 fdiagnostics-color=
1375 Driver Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1376 -fdiagnostics-color=[never|always|auto] Colorize diagnostics.
1378 ; Required for these enum values.
1379 SourceInclude
1380 diagnostic-color.h
1382 Enum
1383 Name(diagnostic_color_rule) Type(int)
1385 EnumValue
1386 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1388 EnumValue
1389 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1391 EnumValue
1392 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1394 fdiagnostics-urls=
1395 Driver Common Joined RejectNegative Var(flag_diagnostics_show_urls) Enum(diagnostic_url_rule) Init(DIAGNOSTICS_URL_AUTO)
1396 -fdiagnostics-urls=[never|always|auto]  Embed URLs in diagnostics.
1398 ; Required for these enum values.
1399 SourceInclude
1400 diagnostic-url.h
1402 Enum
1403 Name(diagnostic_url_rule) Type(int)
1405 EnumValue
1406 Enum(diagnostic_url_rule) String(never) Value(DIAGNOSTICS_URL_NO)
1408 EnumValue
1409 Enum(diagnostic_url_rule) String(always) Value(DIAGNOSTICS_URL_YES)
1411 EnumValue
1412 Enum(diagnostic_url_rule) String(auto) Value(DIAGNOSTICS_URL_AUTO)
1414 fdiagnostics-column-unit=
1415 Common Joined RejectNegative Enum(diagnostics_column_unit)
1416 -fdiagnostics-column-unit=[display|byte]        Select whether column numbers are output as display columns (default) or raw bytes.
1418 fdiagnostics-column-origin=
1419 Common Joined RejectNegative UInteger
1420 -fdiagnostics-column-origin=<number>    Set the number of the first column.  The default is 1-based as per GNU style, but some utilities may expect 0-based, for example.
1422 fdiagnostics-format=
1423 Common Joined RejectNegative Enum(diagnostics_output_format)
1424 -fdiagnostics-format=[text|sarif-stderr|sarif-file|json|json-stderr|json-file]  Select output format.
1426 fdiagnostics-escape-format=
1427 Common Joined RejectNegative Enum(diagnostics_escape_format)
1428 -fdiagnostics-escape-format=[unicode|bytes]     Select how to escape non-printable-ASCII bytes in the source for diagnostics that suggest it.
1430 ; Required for these enum values.
1431 SourceInclude
1432 diagnostic.h
1434 Enum
1435 Name(diagnostics_column_unit) Type(int)
1437 EnumValue
1438 Enum(diagnostics_column_unit) String(display) Value(DIAGNOSTICS_COLUMN_UNIT_DISPLAY)
1440 EnumValue
1441 Enum(diagnostics_column_unit) String(byte) Value(DIAGNOSTICS_COLUMN_UNIT_BYTE)
1443 Enum
1444 Name(diagnostics_escape_format) Type(int)
1446 EnumValue
1447 Enum(diagnostics_escape_format) String(unicode) Value(DIAGNOSTICS_ESCAPE_FORMAT_UNICODE)
1449 EnumValue
1450 Enum(diagnostics_escape_format) String(bytes) Value(DIAGNOSTICS_ESCAPE_FORMAT_BYTES)
1452 Enum
1453 Name(diagnostics_output_format) Type(int)
1455 EnumValue
1456 Enum(diagnostics_output_format) String(text) Value(DIAGNOSTICS_OUTPUT_FORMAT_TEXT)
1458 EnumValue
1459 Enum(diagnostics_output_format) String(json) Value(DIAGNOSTICS_OUTPUT_FORMAT_JSON_STDERR)
1461 EnumValue
1462 Enum(diagnostics_output_format) String(json-stderr) Value(DIAGNOSTICS_OUTPUT_FORMAT_JSON_STDERR)
1464 EnumValue
1465 Enum(diagnostics_output_format) String(json-file) Value(DIAGNOSTICS_OUTPUT_FORMAT_JSON_FILE)
1467 EnumValue
1468 Enum(diagnostics_output_format) String(sarif-stderr) Value(DIAGNOSTICS_OUTPUT_FORMAT_SARIF_STDERR)
1470 EnumValue
1471 Enum(diagnostics_output_format) String(sarif-file) Value(DIAGNOSTICS_OUTPUT_FORMAT_SARIF_FILE)
1473 fdiagnostics-parseable-fixits
1474 Common Var(flag_diagnostics_parseable_fixits)
1475 Print fix-it hints in machine-readable form.
1477 fdiagnostics-generate-patch
1478 Common Var(flag_diagnostics_generate_patch)
1479 Print fix-it hints to stderr in unified diff format.
1481 fdiagnostics-show-option
1482 Common Var(flag_diagnostics_show_option) Init(1)
1483 Amend appropriate diagnostic messages with the command line option that controls them.
1485 fdiagnostics-show-cwe
1486 Common Var(flag_diagnostics_show_cwe) Init(1)
1487 Print CWE identifiers for diagnostic messages, where available.
1489 fdiagnostics-show-rules
1490 Common Var(flag_diagnostics_show_rules) Init(1)
1491 Print any rules associated with diagnostic messages.
1493 fdiagnostics-path-format=
1494 Common Joined RejectNegative Var(flag_diagnostics_path_format) Enum(diagnostic_path_format) Init(DPF_INLINE_EVENTS)
1495 Specify how to print any control-flow path associated with a diagnostic.
1497 fdiagnostics-plain-output
1498 Driver Common RejectNegative
1499 Turn off any diagnostics features that complicate the output, such as line numbers, color, and warning URLs.
1501 ftabstop=
1502 Common Joined RejectNegative UInteger
1503 -ftabstop=<number>      Distance between tab stops for column reporting.
1505 Enum
1506 Name(diagnostic_path_format) Type(int)
1508 EnumValue
1509 Enum(diagnostic_path_format) String(none) Value(DPF_NONE)
1511 EnumValue
1512 Enum(diagnostic_path_format) String(separate-events) Value(DPF_SEPARATE_EVENTS)
1514 EnumValue
1515 Enum(diagnostic_path_format) String(inline-events) Value(DPF_INLINE_EVENTS)
1517 fdiagnostics-show-path-depths
1518 Common Var(flag_diagnostics_show_path_depths) Init(0)
1519 Show stack depths of events in paths.
1521 fdiagnostics-text-art-charset=
1522 Driver Common Joined RejectNegative Var(flag_diagnostics_text_art_charset) Enum(diagnostic_text_art_charset) Init(DIAGNOSTICS_TEXT_ART_CHARSET_EMOJI)
1523 -fdiagnostics-text-art-charset=[none|ascii|unicode|emoji]       Determine which characters to use in text arg diagrams.
1525 Enum
1526 Name(diagnostic_text_art_charset) Type(int)
1528 EnumValue
1529 Enum(diagnostic_text_art_charset) String(none) Value(DIAGNOSTICS_TEXT_ART_CHARSET_NONE)
1531 EnumValue
1532 Enum(diagnostic_text_art_charset) String(ascii) Value(DIAGNOSTICS_TEXT_ART_CHARSET_ASCII)
1534 EnumValue
1535 Enum(diagnostic_text_art_charset) String(unicode) Value(DIAGNOSTICS_TEXT_ART_CHARSET_UNICODE)
1537 EnumValue
1538 Enum(diagnostic_text_art_charset) String(emoji) Value(DIAGNOSTICS_TEXT_ART_CHARSET_EMOJI)
1540 fdiagnostics-minimum-margin-width=
1541 Common Joined UInteger Var(diagnostics_minimum_margin_width) Init(6)
1542 Set minimum width of left margin of source code when showing source.
1544 fdisable-
1545 Common Joined RejectNegative Var(common_deferred_options) Defer
1546 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2   Disable an optimization pass.
1548 fenable-
1549 Common Joined RejectNegative Var(common_deferred_options) Defer
1550 -fenable-[tree|rtl|ipa]-<pass>=range1+range2    Enable an optimization pass.
1552 fdump-
1553 Common Joined RejectNegative Var(common_deferred_options) Defer
1554 -fdump-<type>   Dump various compiler internals to a file.
1556 fdump-final-insns
1557 Driver RejectNegative
1559 fdump-final-insns=
1560 Common RejectNegative Joined Var(flag_dump_final_insns)
1561 -fdump-final-insns=filename     Dump to filename the insns at the end of translation.
1563 fdump-go-spec=
1564 Common RejectNegative Joined Var(flag_dump_go_spec)
1565 -fdump-go-spec=filename Write all declarations to file as Go code.
1567 fdump-noaddr
1568 Common Var(flag_dump_noaddr)
1569 Suppress output of addresses in debugging dumps.
1571 freport-bug
1572 Common Driver Var(flag_report_bug)
1573 Collect and dump debug information into temporary file if ICE in C/C++
1574 compiler occurred.
1576 fdump-internal-locations
1577 Common Var(flag_dump_locations) Init(0)
1578 Dump detailed information on GCC's internal representation of source code locations.
1580 fdump-passes
1581 Common Var(flag_dump_passes) Init(0)
1582 Dump optimization passes.
1584 fdump-unnumbered
1585 Common Var(flag_dump_unnumbered)
1586 Suppress output of instruction numbers, line number notes and addresses in debugging dumps.
1588 fdump-unnumbered-links
1589 Common Var(flag_dump_unnumbered_links)
1590 Suppress output of previous and next insn numbers in debugging dumps.
1592 fdwarf2-cfi-asm
1593 Common Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1594 Enable CFI tables via GAS assembler directives.
1596 fearly-inlining
1597 Common Var(flag_early_inlining) Init(1) Optimization
1598 Perform early inlining.
1600 feliminate-dwarf2-dups
1601 Common Ignore
1602 Does nothing.  Preserved for backward compatibility.
1604 fipa-sra
1605 Common Var(flag_ipa_sra) Init(0) Optimization
1606 Perform interprocedural reduction of aggregates.
1608 feliminate-unused-debug-symbols
1609 Common Var(flag_debug_only_used_symbols) Init(1)
1610 Perform unused symbol elimination in debug info.
1612 feliminate-unused-debug-types
1613 Common Var(flag_eliminate_unused_debug_types) Init(1)
1614 Perform unused type elimination in debug info.
1616 femit-class-debug-always
1617 Common Var(flag_emit_class_debug_always) Init(0)
1618 Do not suppress C++ class debug information.
1620 fexceptions
1621 Common Var(flag_exceptions) Optimization EnabledBy(fnon-call-exceptions)
1622 Enable exception handling.
1624 fexpensive-optimizations
1625 Common Var(flag_expensive_optimizations) Optimization
1626 Perform a number of minor, expensive optimizations.
1628 fexcess-precision=
1629 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision) Init(EXCESS_PRECISION_DEFAULT) Optimization SetByCombined
1630 -fexcess-precision=[fast|standard|16]   Specify handling of excess floating-point precision.
1632 Enum
1633 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1635 EnumValue
1636 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1638 EnumValue
1639 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1641 EnumValue
1642 Enum(excess_precision) String(16) Value(EXCESS_PRECISION_FLOAT16)
1644 ; Whether we permit the extended set of values for FLT_EVAL_METHOD
1645 ; introduced in ISO/IEC TS 18661-3, or limit ourselves to those in C99/C11.
1646 fpermitted-flt-eval-methods=
1647 Common Joined RejectNegative Enum(permitted_flt_eval_methods) Var(flag_permitted_flt_eval_methods) Init(PERMITTED_FLT_EVAL_METHODS_DEFAULT)
1648 -fpermitted-flt-eval-methods=[c11|ts-18661]     Specify which values of FLT_EVAL_METHOD are permitted.
1650 Enum
1651 Name(permitted_flt_eval_methods) Type(enum permitted_flt_eval_methods) UnknownError(unknown specification for the set of FLT_EVAL_METHOD values to permit %qs)
1653 EnumValue
1654 Enum(permitted_flt_eval_methods) String(c11) Value(PERMITTED_FLT_EVAL_METHODS_C11)
1656 EnumValue
1657 Enum(permitted_flt_eval_methods) String(ts-18661-3) Value(PERMITTED_FLT_EVAL_METHODS_TS_18661)
1659 ffast-math
1660 Common Optimization
1662 ffat-lto-objects
1663 Common Var(flag_fat_lto_objects)
1664 Output lto objects containing both the intermediate language and binary output.
1666 ffinite-math-only
1667 Common Var(flag_finite_math_only) Optimization SetByCombined
1668 Assume no NaNs or infinities are generated.
1670 ffinite-loops
1671 Common Var(flag_finite_loops) Optimization Init(0)
1672 Assume that loops with an exit will terminate and not loop indefinitely.
1674 ffixed-
1675 Common Joined RejectNegative Var(common_deferred_options) Defer
1676 -ffixed-<register>      Mark <register> as being unavailable to the compiler.
1678 ffloat-store
1679 Common Var(flag_float_store) Optimization
1680 Don't allocate floats and doubles in extended-precision registers.
1682 fforce-addr
1683 Common Ignore
1684 Does nothing.  Preserved for backward compatibility.
1686 fforward-propagate
1687 Common Var(flag_forward_propagate) Optimization
1688 Perform a forward propagation pass on RTL.
1690 ffp-contract=
1691 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST) Optimization
1692 -ffp-contract=[off|on|fast]     Perform floating-point expression contraction.
1694 Enum
1695 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1697 EnumValue
1698 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1700 EnumValue
1701 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_ON)
1703 EnumValue
1704 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1706 ffp-int-builtin-inexact
1707 Common Var(flag_fp_int_builtin_inexact) Init(1) Optimization
1708 Allow built-in functions ceil, floor, round, trunc to raise \"inexact\" exceptions.
1710 ; Nonzero means don't put addresses of constant functions in registers.
1711 ; Used for compiling the Unix kernel, where strange substitutions are
1712 ; done on the assembly output.
1713 ffunction-cse
1714 Common Var(flag_no_function_cse,0) Optimization
1715 Allow function addresses to be held in registers.
1717 ffunction-sections
1718 Common Var(flag_function_sections)
1719 Place each function into its own section.
1721 fgcse
1722 Common Var(flag_gcse) Optimization
1723 Perform global common subexpression elimination.
1725 fgcse-lm
1726 Common Var(flag_gcse_lm) Init(1) Optimization
1727 Perform enhanced load motion during global common subexpression elimination.
1729 fgcse-sm
1730 Common Var(flag_gcse_sm) Init(0) Optimization
1731 Perform store motion after global common subexpression elimination.
1733 fgcse-las
1734 Common Var(flag_gcse_las) Init(0) Optimization
1735 Perform redundant load after store elimination in global common subexpression
1736 elimination.
1738 fgcse-after-reload
1739 Common Var(flag_gcse_after_reload) Optimization
1740 Perform global common subexpression elimination after register allocation has
1741 finished.
1743 Enum
1744 Name(dwarf_gnat_encodings) Type(int)
1746 EnumValue
1747 Enum(dwarf_gnat_encodings) String(all) Value(DWARF_GNAT_ENCODINGS_ALL)
1749 EnumValue
1750 Enum(dwarf_gnat_encodings) String(gdb) Value(DWARF_GNAT_ENCODINGS_GDB)
1752 EnumValue
1753 Enum(dwarf_gnat_encodings) String(minimal) Value(DWARF_GNAT_ENCODINGS_MINIMAL)
1755 fgnat-encodings=
1756 Common Enum(dwarf_gnat_encodings) Joined RejectNegative Undocumented Var(gnat_encodings)
1757 -fgnat-encodings=[all|gdb|minimal]      Select the balance between GNAT encodings and standard DWARF emitted in the debug information.
1759 ; This option is not documented yet as its semantics will change.
1760 fgraphite
1761 Common Var(flag_graphite) Optimization
1762 Enable in and out of Graphite representation.
1764 fgraphite-identity
1765 Common Var(flag_graphite_identity) Optimization
1766 Enable Graphite Identity transformation.
1768 fhoist-adjacent-loads
1769 Common Var(flag_hoist_adjacent_loads) Optimization
1770 Enable hoisting adjacent loads to encourage generating conditional move
1771 instructions.
1773 fkeep-gc-roots-live
1774 Common Undocumented Var(flag_keep_gc_roots_live) Optimization
1775 ; Always keep a pointer to a live memory block
1777 flarge-source-files
1778 Common Var(flag_large_source_files) Init(0)
1779 Improve GCC's ability to track column numbers in large source files,
1780 at the expense of slower compilation.
1782 floop-parallelize-all
1783 Common Var(flag_loop_parallelize_all) Optimization
1784 Mark all loops as parallel.
1786 floop-strip-mine
1787 Common Alias(floop-nest-optimize)
1788 Enable loop nest transforms.  Same as -floop-nest-optimize.
1790 floop-interchange
1791 Common Var(flag_loop_interchange) Optimization
1792 Enable loop interchange on trees.
1794 floop-block
1795 Common Alias(floop-nest-optimize)
1796 Enable loop nest transforms.  Same as -floop-nest-optimize.
1798 floop-unroll-and-jam
1799 Common Var(flag_unroll_jam) Optimization
1800 Perform unroll-and-jam on loops.
1802 fgnu-tm
1803 Common Var(flag_tm)
1804 Enable support for GNU transactional memory.
1806 fgnu-unique
1807 Common Var(flag_gnu_unique) Init(1)
1808 Use STB_GNU_UNIQUE if supported by the assembler.
1810 floop-flatten
1811 Common Ignore
1812 Does nothing. Preserved for backward compatibility.
1814 floop-nest-optimize
1815 Common Var(flag_loop_nest_optimize) Optimization
1816 Enable the loop nest optimizer.
1818 fstrict-volatile-bitfields
1819 Common Var(flag_strict_volatile_bitfields) Init(-1) Optimization
1820 Force bitfield accesses to match their type width.
1822 fstore-merging
1823 Common Var(flag_store_merging) Optimization
1824 Merge adjacent stores.
1826 fguess-branch-probability
1827 Common Var(flag_guess_branch_prob) Optimization
1828 Enable guessing of branch probabilities.
1830 fhardened
1831 Common Driver Var(flag_hardened)
1832 Enable various security-relevant flags.
1834 fharden-compares
1835 Common Var(flag_harden_compares) Optimization
1836 Harden conditionals not used in branches, checking reversed conditions.
1838 fharden-conditional-branches
1839 Common Var(flag_harden_conditional_branches) Optimization
1840 Harden conditional branches by checking reversed conditions.
1842 fharden-control-flow-redundancy
1843 Common Var(flag_harden_control_flow_redundancy) Optimization
1844 Harden control flow by recording and checking execution paths.
1846 fhardcfr-skip-leaf
1847 Common Var(flag_harden_control_flow_redundancy_skip_leaf) Optimization
1848 Disable CFR in leaf functions.
1850 fhardcfr-check-returning-calls
1851 Common Var(flag_harden_control_flow_redundancy_check_returning_calls) Init(-1) Optimization
1852 Check CFR execution paths also before calls followed by returns of their results.
1854 fhardcfr-check-exceptions
1855 Common Var(flag_harden_control_flow_redundancy_check_exceptions) Init(-1) Optimization
1856 Check CFR execution paths also when exiting a function through an exception.
1858 fhardcfr-check-noreturn-calls=
1859 Common Joined RejectNegative Enum(hardcfr_check_noreturn_calls) Var(flag_harden_control_flow_redundancy_check_noreturn) Init(HCFRNR_UNSPECIFIED) Optimization
1860 -fhardcfr-check-noreturn-calls=[always|no-xthrow|nothrow|never] Check CFR execution paths also before calling noreturn functions.
1862 Enum
1863 Name(hardcfr_check_noreturn_calls) Type(enum hardcfr_noret) UnknownError(unknown hardcfr noreturn checking level %qs)
1865 EnumValue
1866 Enum(hardcfr_check_noreturn_calls) String(never) Value(HCFRNR_NEVER)
1868 EnumValue
1869 Enum(hardcfr_check_noreturn_calls) String(nothrow) Value(HCFRNR_NOTHROW)
1871 EnumValue
1872 Enum(hardcfr_check_noreturn_calls) String(no-xthrow) Value(HCFRNR_NO_XTHROW)
1874 EnumValue
1875 Enum(hardcfr_check_noreturn_calls) String(always) Value(HCFRNR_ALWAYS)
1877 ; Nonzero means ignore `#ident' directives.  0 means handle them.
1878 ; Generate position-independent code for executables if possible
1879 ; On SVR4 targets, it also controls whether or not to emit a
1880 ; string identifying the compiler.
1881 fident
1882 Common Var(flag_no_ident,0)
1883 Process #ident directives.
1885 fif-conversion
1886 Common Var(flag_if_conversion) Optimization
1887 Perform conversion of conditional jumps to branchless equivalents.
1889 fif-conversion2
1890 Common Var(flag_if_conversion2) Optimization
1891 Perform conversion of conditional jumps to conditional execution.
1893 fstack-reuse=
1894 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL) Optimization
1895 -fstack-reuse=[all|named_vars|none]     Set stack reuse level for local variables.
1897 Enum
1898 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1900 EnumValue
1901 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1903 EnumValue
1904 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1906 EnumValue
1907 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1909 ftree-loop-if-convert
1910 Common Var(flag_tree_loop_if_convert) Init(-1) Optimization
1911 Convert conditional jumps in innermost loops to branchless equivalents.
1913 ftree-loop-if-convert-stores
1914 Common Ignore
1915 Does nothing. Preserved for backward compatibility.
1917 ; -finhibit-size-directive inhibits output of .size for ELF.
1918 ; This is used only for compiling crtstuff.c,
1919 ; and it may be extended to other effects
1920 ; needed for crtstuff.c on other systems.
1921 finhibit-size-directive
1922 Common Var(flag_inhibit_size_directive)
1923 Do not generate .size directives.
1925 findirect-inlining
1926 Common Var(flag_indirect_inlining) Optimization
1927 Perform indirect inlining.
1929 ; General flag to enable inlining.  Specifying -fno-inline will disable
1930 ; all inlining apart from always-inline functions.
1931 finline
1932 Common Var(flag_no_inline,0) Init(0) Optimization
1933 Enable inlining of function declared \"inline\", disabling disables all inlining.
1935 finline-small-functions
1936 Common Var(flag_inline_small_functions) Optimization
1937 Integrate functions into their callers when code size is known not to grow.
1939 finline-functions
1940 Common Var(flag_inline_functions) Optimization
1941 Integrate functions not declared \"inline\" into their callers when profitable.
1943 finline-functions-called-once
1944 Common Var(flag_inline_functions_called_once) Optimization
1945 Integrate functions only required by their single caller.
1947 finline-limit-
1948 Common RejectNegative Joined Alias(finline-limit=)
1950 finline-limit=
1951 Common RejectNegative Joined UInteger
1952 -finline-limit=<number> Limit the size of inlined functions to <number>.
1954 finline-atomics
1955 Common Var(flag_inline_atomics) Init(1) Optimization
1956 Inline __atomic operations when a lock free instruction sequence is available.
1958 fcf-protection
1959 Common RejectNegative Alias(fcf-protection=,full)
1961 fcf-protection=
1962 Common Joined RejectNegative Enum(cf_protection_level) EnumSet Var(flag_cf_protection) Init(CF_NONE)
1963 -fcf-protection=[full|branch|return|none|check] Instrument functions with checks to verify jump/call/return control-flow transfer
1964 instructions have valid targets.
1966 Enum
1967 Name(cf_protection_level) Type(enum cf_protection_level) UnknownError(unknown Control-Flow Protection Level %qs)
1969 EnumValue
1970 Enum(cf_protection_level) String(full) Value(CF_FULL) Set(1)
1972 EnumValue
1973 Enum(cf_protection_level) String(branch) Value(CF_BRANCH) Set(2)
1975 EnumValue
1976 Enum(cf_protection_level) String(return) Value(CF_RETURN) Set(3)
1978 EnumValue
1979 Enum(cf_protection_level) String(check) Value(CF_CHECK) Set(4)
1981 EnumValue
1982 Enum(cf_protection_level) String(none) Value(CF_NONE) Set(1)
1984 finstrument-functions
1985 Common Var(flag_instrument_function_entry_exit,1)
1986 Instrument function entry and exit with profiling calls.
1988 finstrument-functions-once
1989 Common Var(flag_instrument_function_entry_exit,2)
1990 Instrument function entry and exit with profiling calls invoked once.
1992 finstrument-functions-exclude-function-list=
1993 Common RejectNegative Joined
1994 -finstrument-functions-exclude-function-list=name,...   Do not instrument listed functions.
1996 finstrument-functions-exclude-file-list=
1997 Common RejectNegative Joined
1998 -finstrument-functions-exclude-file-list=filename,...   Do not instrument functions listed in files.
2000 fipa-cp
2001 Common Var(flag_ipa_cp) Optimization
2002 Perform interprocedural constant propagation.
2004 fipa-cp-clone
2005 Common Var(flag_ipa_cp_clone) Optimization
2006 Perform cloning to make Interprocedural constant propagation stronger.
2008 fipa-cp-alignment
2009 Common Ignore
2010 Does nothing.  Preserved for backward compatibility.
2012 fipa-bit-cp
2013 Common Var(flag_ipa_bit_cp) Optimization
2014 Perform interprocedural bitwise constant propagation.
2016 fipa-modref
2017 Common Var(flag_ipa_modref) Optimization
2018 Perform interprocedural modref analysis.
2020 fipa-profile
2021 Common Var(flag_ipa_profile) Init(0) Optimization
2022 Perform interprocedural profile propagation.
2024 fipa-pta
2025 Common Var(flag_ipa_pta) Init(0) Optimization
2026 Perform interprocedural points-to analysis.
2028 fipa-pure-const
2029 Common Var(flag_ipa_pure_const) Init(0) Optimization
2030 Discover pure and const functions.
2032 fipa-icf
2033 Common Var(flag_ipa_icf) Optimization
2034 Perform Identical Code Folding for functions and read-only variables.
2036 fipa-icf-functions
2037 Common Var(flag_ipa_icf_functions) Optimization
2038 Perform Identical Code Folding for functions.
2040 fipa-icf-variables
2041 Common Var(flag_ipa_icf_variables) Optimization
2042 Perform Identical Code Folding for variables.
2044 fipa-reference
2045 Common Var(flag_ipa_reference) Init(0) Optimization
2046 Discover read-only and non addressable static variables.
2048 fipa-reference-addressable
2049 Common Var(flag_ipa_reference_addressable) Init(0) Optimization
2050 Discover read-only, write-only and non-addressable static variables.
2052 fipa-stack-alignment
2053 Common Var(flag_ipa_stack_alignment) Init(1) Optimization
2054 Reduce stack alignment on call sites if possible.
2056 fipa-matrix-reorg
2057 Common Ignore
2058 Does nothing. Preserved for backward compatibility.
2060 fipa-struct-reorg
2061 Common Ignore
2062 Does nothing. Preserved for backward compatibility.
2064 fipa-vrp
2065 Common Var(flag_ipa_vrp) Optimization
2066 Perform IPA Value Range Propagation.
2068 fira-algorithm=
2069 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB) Optimization
2070 -fira-algorithm=[CB|priority]   Set the used IRA algorithm.
2072 fipa-strict-aliasing
2073 Common Var(flag_ipa_strict_aliasing) Init(1) Optimization
2074 Assume strict aliasing rules apply across (uninlined) function boundaries.
2076 Enum
2077 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
2079 EnumValue
2080 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
2082 EnumValue
2083 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
2085 fira-region=
2086 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_ONE) Optimization
2087 -fira-region=[one|all|mixed]    Set regions for IRA.
2089 Enum
2090 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
2092 EnumValue
2093 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
2095 EnumValue
2096 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
2098 EnumValue
2099 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
2101 fira-hoist-pressure
2102 Common Var(flag_ira_hoist_pressure) Init(1) Optimization
2103 Use IRA based register pressure calculation
2104 in RTL hoist optimizations.
2106 fira-loop-pressure
2107 Common Var(flag_ira_loop_pressure) Optimization
2108 Use IRA based register pressure calculation
2109 in RTL loop optimizations.
2111 fira-share-save-slots
2112 Common Var(flag_ira_share_save_slots) Init(1) Optimization
2113 Share slots for saving different hard registers.
2115 fira-share-spill-slots
2116 Common Var(flag_ira_share_spill_slots) Init(1) Optimization
2117 Share stack slots for spilled pseudo-registers.
2119 fira-verbose=
2120 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
2121 -fira-verbose=<number>  Control IRA's level of diagnostic messages.
2123 fivopts
2124 Common Var(flag_ivopts) Init(1) Optimization
2125 Optimize induction variables on trees.
2127 fjump-tables
2128 Common Var(flag_jump_tables) Init(1) Optimization
2129 Use jump tables for sufficiently large switch statements.
2131 fbit-tests
2132 Common Var(flag_bit_tests) Init(1) Optimization
2133 Use bit tests for sufficiently large switch statements.
2135 fkeep-inline-functions
2136 Common Var(flag_keep_inline_functions)
2137 Generate code for functions even if they are fully inlined.
2139 fkeep-static-functions
2140 Common Var(flag_keep_static_functions)
2141 Generate code for static functions even if they are never called.
2143 fkeep-static-consts
2144 Common Var(flag_keep_static_consts) Init(1)
2145 Emit static const variables even if they are not used.
2147 fleading-underscore
2148 Common Var(flag_leading_underscore) Init(-1)
2149 Give external symbols a leading underscore.
2151 floop-optimize
2152 Common Ignore
2153 Does nothing.  Preserved for backward compatibility.
2155 flra-remat
2156 Common Var(flag_lra_remat) Optimization
2157 Do CFG-sensitive rematerialization in LRA.
2159 flto
2160 Common
2161 Enable link-time optimization.
2163 flto=
2164 Common RejectNegative Joined Var(flag_lto)
2165 Link-time optimization with number of parallel jobs or jobserver.
2167 Enum
2168 Name(lto_partition_model) Type(enum lto_partition_model) UnknownError(unknown LTO partitioning model %qs)
2170 EnumValue
2171 Enum(lto_partition_model) String(none) Value(LTO_PARTITION_NONE)
2173 EnumValue
2174 Enum(lto_partition_model) String(one) Value(LTO_PARTITION_ONE)
2176 EnumValue
2177 Enum(lto_partition_model) String(balanced) Value(LTO_PARTITION_BALANCED)
2179 EnumValue
2180 Enum(lto_partition_model) String(1to1) Value(LTO_PARTITION_1TO1)
2182 EnumValue
2183 Enum(lto_partition_model) String(max) Value(LTO_PARTITION_MAX)
2185 flto-partition=
2186 Common Joined RejectNegative Enum(lto_partition_model) Var(flag_lto_partition) Init(LTO_PARTITION_BALANCED)
2187 Specify the algorithm to partition symbols and vars at linktime.
2189 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
2190 flto-compression-level=
2191 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1) IntegerRange(0, 19)
2192 Use zlib/zstd compression level <number> for IL.
2194 flto-odr-type-merging
2195 Common Ignore
2196 Does nothing.  Preserved for backward compatibility.
2198 flto-report
2199 Common Var(flag_lto_report) Init(0)
2200 Report various link-time optimization statistics.
2202 flto-report-wpa
2203 Common Var(flag_lto_report_wpa) Init(0)
2204 Report various link-time optimization statistics for WPA only.
2206 fmath-errno
2207 Common Var(flag_errno_math) Init(1) Optimization SetByCombined
2208 Set errno after built-in math functions.
2210 fmax-errors=
2211 Common Joined RejectNegative UInteger Var(flag_max_errors)
2212 -fmax-errors=<number>   Maximum number of errors to report.
2214 fmem-report
2215 Common Var(mem_report)
2216 Report on permanent memory allocation.
2218 fmem-report-wpa
2219 Common Var(mem_report_wpa)
2220 Report on permanent memory allocation in WPA only.
2222 ; This will attempt to merge constant section constants, if 1 only
2223 ; string constants and constants from constant pool, if 2 also constant
2224 ; variables.
2225 fmerge-all-constants
2226 Common Var(flag_merge_constants,2) Init(1)
2227 Attempt to merge identical constants and constant variables.
2229 fmerge-constants
2230 Common Var(flag_merge_constants,1)
2231 Attempt to merge identical constants across compilation units.
2233 fmerge-debug-strings
2234 Common Var(flag_merge_debug_strings) Init(1)
2235 Attempt to merge identical debug strings across compilation units.
2237 fmessage-length=
2238 Common RejectNegative Joined UInteger
2239 -fmessage-length=<number>       Limit diagnostics to <number> characters per line.  0 suppresses line-wrapping.
2241 fmodulo-sched
2242 Common Var(flag_modulo_sched) Optimization
2243 Perform SMS based modulo scheduling before the first scheduling pass.
2245 fmodulo-sched-allow-regmoves
2246 Common Var(flag_modulo_sched_allow_regmoves) Optimization
2247 Perform SMS based modulo scheduling with register moves allowed.
2249 fmove-loop-invariants
2250 Common Var(flag_move_loop_invariants) Optimization
2251 Move loop invariant computations out of loops.
2253 fmove-loop-stores
2254 Common Var(flag_move_loop_stores) Optimization
2255 Move stores out of loops.
2257 fmultiflags
2258 Common Driver
2259 Building block for specs-based multilib-aware TFLAGS.
2261 fdce
2262 Common Var(flag_dce) Init(1) Optimization
2263 Use the RTL dead code elimination pass.
2265 fdse
2266 Common Var(flag_dse) Init(0) Optimization
2267 Use the RTL dead store elimination pass.
2269 freschedule-modulo-scheduled-loops
2270 Common Var(flag_resched_modulo_sched) Optimization
2271 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling.
2273 fnon-call-exceptions
2274 Common Var(flag_non_call_exceptions) Optimization
2275 Support synchronous non-call exceptions.
2277 foffload=
2278 Driver Joined MissingArgError(targets missing after %qs)
2280 foffload-options=
2281 Common Driver Joined MissingArgError(options or targets=options missing after %qs)
2282 -foffload-options=<targets>=<options>   Specify options for the offloading targets.
2284 foffload-abi=
2285 Common Joined RejectNegative Enum(offload_abi)
2286 -foffload-abi=[lp64|ilp32]      Set the ABI to use in an offload compiler.
2288 Enum
2289 Name(offload_abi) Type(enum offload_abi) UnknownError(unknown offload ABI %qs)
2291 EnumValue
2292 Enum(offload_abi) String(ilp32) Value(OFFLOAD_ABI_ILP32)
2294 EnumValue
2295 Enum(offload_abi) String(lp64) Value(OFFLOAD_ABI_LP64)
2297 fomit-frame-pointer
2298 Common Var(flag_omit_frame_pointer) Optimization
2299 When possible do not generate stack frames.
2301 fopenmp-target-simd-clone
2302 Common Alias(fopenmp-target-simd-clone=,any,none)
2304 fopenmp-target-simd-clone=
2305 Common Joined RejectNegative Enum(target_simd_clone_device) Var(flag_openmp_target_simd_clone) Init(OMP_TARGET_SIMD_CLONE_NONE) Optimization
2306 Generate SIMD clones for functions with the OpenMP declare target directive.
2308 Enum
2309 Name(target_simd_clone_device) Type(int)
2311 EnumValue
2312 Enum(target_simd_clone_device) String(none) Value(OMP_TARGET_SIMD_CLONE_NONE)
2314 EnumValue
2315 Enum(target_simd_clone_device) String(host) Value(OMP_TARGET_SIMD_CLONE_HOST)
2317 EnumValue
2318 Enum(target_simd_clone_device) String(nohost) Value(OMP_TARGET_SIMD_CLONE_NOHOST)
2320 EnumValue
2321 Enum(target_simd_clone_device) String(any) Value(OMP_TARGET_SIMD_CLONE_ANY)
2323 fopt-info
2324 Common Var(flag_opt_info) Optimization
2325 Enable all optimization info dumps on stderr.
2327 fopt-info-
2328 Common Joined RejectNegative Var(common_deferred_options) Defer
2329 -fopt-info[-<type>=filename]    Dump compiler optimization details.
2331 fsave-optimization-record
2332 Common Var(flag_save_optimization_record) Optimization
2333 Write a SRCFILE.opt-record.json file detailing what optimizations were performed.
2335 foptimize-register-move
2336 Common Ignore
2337 Does nothing. Preserved for backward compatibility.
2339 foptimize-sibling-calls
2340 Common Var(flag_optimize_sibling_calls) Optimization
2341 Optimize sibling and tail recursive calls.
2343 fpartial-inlining
2344 Common Var(flag_partial_inlining) Optimization
2345 Perform partial inlining.
2347 fpre-ipa-mem-report
2348 Common Var(pre_ipa_mem_report)
2349 Report on memory allocation before interprocedural optimization.
2351 fpost-ipa-mem-report
2352 Common Var(post_ipa_mem_report)
2353 Report on memory allocation before interprocedural optimization.
2355 fpack-struct
2356 Common Var(flag_pack_struct) Optimization
2357 Pack structure members together without holes.
2359 fpack-struct=
2360 Common RejectNegative Joined UInteger Optimization
2361 -fpack-struct=<number>  Set initial maximum structure member alignment.
2363 fpcc-struct-return
2364 Common Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
2365 Return small aggregates in memory, not registers.
2367 fpeel-loops
2368 Common Var(flag_peel_loops) Optimization
2369 Perform loop peeling.
2371 fpeephole
2372 Common Var(flag_no_peephole,0) Optimization
2373 Enable machine specific peephole optimizations.
2375 fpeephole2
2376 Common Var(flag_peephole2) Optimization
2377 Enable an RTL peephole pass before sched2.
2379 fPIC
2380 Common Var(flag_pic,2) Negative(fPIE) Init(-1)
2381 Generate position-independent code if possible (large mode).
2383 fPIE
2384 Common Var(flag_pie,2) Negative(fpic) Init(-1)
2385 Generate position-independent code for executables if possible (large mode).
2387 fpic
2388 Common Var(flag_pic,1) Negative(fpie) Init(-1)
2389 Generate position-independent code if possible (small mode).
2391 fpie
2392 Common Var(flag_pie,1) Negative(fPIC) Init(-1)
2393 Generate position-independent code for executables if possible (small mode).
2395 fplt
2396 Common Var(flag_plt) Init(1) Optimization
2397 Use PLT for PIC calls (-fno-plt: load the address from GOT at call site).
2399 fplugin=
2400 Common Joined RejectNegative Var(common_deferred_options) Defer
2401 Specify a plugin to load.
2403 fplugin-arg-
2404 Common Joined RejectNegative Var(common_deferred_options) Defer
2405 -fplugin-arg-<name>-<key>[=<value>]     Specify argument <key>=<value> for plugin <name>.
2407 fpredictive-commoning
2408 Common Var(flag_predictive_commoning) Optimization
2409 Run predictive commoning optimization.
2411 fprefetch-loop-arrays
2412 Common Var(flag_prefetch_loop_arrays) Init(-1) Optimization
2413 Generate prefetch instructions, if available, for arrays in loops.
2415 fprofile
2416 Common Var(profile_flag)
2417 Enable basic program profiling code.
2419 fprofile-abs-path
2420 Common Var(profile_abs_path_flag)
2421 Generate absolute source path names for gcov.
2423 fprofile-arcs
2424 Common Var(profile_arc_flag)
2425 Insert arc-based program profiling code.
2427 fprofile-dir=
2428 Common Joined RejectNegative Var(profile_data_prefix)
2429 Set the top-level directory for storing the profile data.
2430 The default is 'pwd'.
2432 fprofile-note=
2433 Common Joined RejectNegative Var(profile_note_location)
2434 Select the name for storing the profile note file.
2436 fprofile-correction
2437 Common Var(flag_profile_correction)
2438 Enable correction of flow inconsistent profile data input.
2440 fprofile-update=
2441 Common Joined RejectNegative Enum(profile_update) Var(flag_profile_update) Init(PROFILE_UPDATE_SINGLE)
2442 -fprofile-update=[single|atomic|prefer-atomic]  Set the profile update method.
2444 fprofile-filter-files=
2445 Common Joined RejectNegative Var(flag_profile_filter_files)
2446 Instrument only functions from files whose name matches any of the regular expressions (separated by semi-colons).
2448 fprofile-exclude-files=
2449 Common Joined RejectNegative Var(flag_profile_exclude_files)
2450 Instrument only functions from files whose name does not match any of the regular expressions (separated by semi-colons).
2452 Enum
2453 Name(profile_reproducibility) Type(enum profile_reproducibility) UnknownError(unknown profile reproducibility method %qs)
2455 EnumValue
2456 Enum(profile_reproducibility) String(serial) Value(PROFILE_REPRODUCIBILITY_SERIAL)
2458 EnumValue
2459 Enum(profile_reproducibility) String(parallel-runs) Value(PROFILE_REPRODUCIBILITY_PARALLEL_RUNS)
2461 EnumValue
2462 Enum(profile_reproducibility) String(multithreaded) Value(PROFILE_REPRODUCIBILITY_MULTITHREADED)
2464 fprofile-reproducible=
2465 Common Joined RejectNegative Var(flag_profile_reproducible) Enum(profile_reproducibility) Init(PROFILE_REPRODUCIBILITY_SERIAL)
2466 -fprofile-reproducible=[serial|parallel-runs|multithreaded]     Control level of reproducibility of profile gathered by -fprofile-generate.
2468 Enum
2469 Name(profile_update) Type(enum profile_update) UnknownError(unknown profile update method %qs)
2471 EnumValue
2472 Enum(profile_update) String(single) Value(PROFILE_UPDATE_SINGLE)
2474 EnumValue
2475 Enum(profile_update) String(atomic) Value(PROFILE_UPDATE_ATOMIC)
2477 EnumValue
2478 Enum(profile_update) String(prefer-atomic) Value(PROFILE_UPDATE_PREFER_ATOMIC)
2480 fprofile-prefix-path=
2481 Common Joined RejectNegative Var(profile_prefix_path)
2482 Remove prefix from absolute path before mangling name for -fprofile-generate= and -fprofile-use=.
2484 fprofile-prefix-map=
2485 Common Joined RejectNegative Var(common_deferred_options) Defer
2486 -fprofile-prefix-map=<old>=<new>        Map one directory name to another in GCOV coverage result.
2488 fprofile-generate
2489 Common
2490 Enable common options for generating profile info for profile feedback directed optimizations.
2492 fprofile-generate=
2493 Common Joined RejectNegative
2494 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=.
2496 fprofile-info-section
2497 Common RejectNegative
2498 Register the profile information in the .gcov_info section instead of using a constructor/destructor.
2500 fprofile-info-section=
2501 Common Joined RejectNegative Var(profile_info_section)
2502 Register the profile information in the specified section instead of using a constructor/destructor.
2504 fprofile-partial-training
2505 Common Var(flag_profile_partial_training) Optimization
2506 Do not assume that functions never executed during the train run are cold.
2508 fprofile-use
2509 Common Var(flag_profile_use)
2510 Enable common options for performing profile feedback directed optimizations.
2512 fprofile-use=
2513 Common Joined RejectNegative
2514 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=.
2516 fprofile-values
2517 Common Var(flag_profile_values)
2518 Insert code to profile values of expressions.
2520 fprofile-report
2521 Common Var(profile_report)
2522 Report on consistency of profile.
2524 fprofile-reorder-functions
2525 Common Var(flag_profile_reorder_functions) Optimization
2526 Enable function reordering that improves code placement.
2528 fpatchable-function-entry=
2529 Common Var(flag_patchable_function_entry) Joined Optimization
2530 Insert NOP instructions at each function entry.
2532 frandom-seed
2533 Common Var(common_deferred_options) Defer
2535 frandom-seed=
2536 Common Joined RejectNegative Var(common_deferred_options) Defer
2537 -frandom-seed=<string>  Make compile reproducible using <string>.
2539 ; This switch causes the command line that was used to create an
2540 ; object file to be recorded into the object file.  The exact format
2541 ; of this recording is target and binary file format dependent.
2542 ; It is related to the -fverbose-asm switch, but that switch only
2543 ; records information in the assembler output file as comments, so
2544 ; they never reach the object file.
2545 frecord-gcc-switches
2546 Common Var(flag_record_gcc_switches)
2547 Record gcc command line switches in the object file.
2549 freg-struct-return
2550 Common Var(flag_pcc_struct_return,0) Optimization
2551 Return small aggregates in registers.
2553 fregmove
2554 Common Ignore
2555 Does nothing. Preserved for backward compatibility.
2557 flifetime-dse
2558 Common Var(flag_lifetime_dse,2) Init(2) Optimization
2559 Tell DSE that the storage for a C++ object is dead when the constructor
2560 starts and when the destructor finishes.
2562 flifetime-dse=
2563 Common Joined RejectNegative UInteger Var(flag_lifetime_dse) Optimization IntegerRange(0, 2)
2565 flive-patching
2566 Common RejectNegative Alias(flive-patching=,inline-clone) Optimization
2568 flive-patching=
2569 Common Joined RejectNegative Enum(live_patching_level) Var(flag_live_patching) Init(LIVE_PATCHING_NONE) Optimization
2570 -flive-patching=[inline-only-static|inline-clone]       Control IPA
2571 optimizations to provide a safe compilation for live-patching.  At the same
2572 time, provides multiple-level control on the enabled IPA optimizations.
2574 Enum
2575 Name(live_patching_level) Type(enum live_patching_level) UnknownError(unknown Live-Patching Level %qs)
2577 EnumValue
2578 Enum(live_patching_level) String(inline-only-static) Value(LIVE_PATCHING_INLINE_ONLY_STATIC)
2580 EnumValue
2581 Enum(live_patching_level) String(inline-clone) Value(LIVE_PATCHING_INLINE_CLONE)
2583 fallocation-dce
2584 Common Var(flag_allocation_dce) Init(1) Optimization
2585 Tell DCE to remove unused C++ allocations.
2587 flive-range-shrinkage
2588 Common Var(flag_live_range_shrinkage) Init(0) Optimization
2589 Relief of register pressure through live range shrinkage.
2591 frename-registers
2592 Common Var(flag_rename_registers) Optimization EnabledBy(funroll-loops)
2593 Perform a register renaming optimization pass.
2595 fschedule-fusion
2596 Common Var(flag_schedule_fusion) Init(2) Optimization
2597 Perform a target dependent instruction fusion optimization pass.
2599 freorder-blocks
2600 Common Var(flag_reorder_blocks) Optimization
2601 Reorder basic blocks to improve code placement.
2603 freorder-blocks-algorithm=
2604 Common Joined RejectNegative Enum(reorder_blocks_algorithm) Var(flag_reorder_blocks_algorithm) Init(REORDER_BLOCKS_ALGORITHM_SIMPLE) Optimization
2605 -freorder-blocks-algorithm=[simple|stc] Set the used basic block reordering algorithm.
2607 Enum
2608 Name(reorder_blocks_algorithm) Type(enum reorder_blocks_algorithm) UnknownError(unknown basic block reordering algorithm %qs)
2610 EnumValue
2611 Enum(reorder_blocks_algorithm) String(simple) Value(REORDER_BLOCKS_ALGORITHM_SIMPLE)
2613 EnumValue
2614 Enum(reorder_blocks_algorithm) String(stc) Value(REORDER_BLOCKS_ALGORITHM_STC)
2616 freorder-blocks-and-partition
2617 Common Var(flag_reorder_blocks_and_partition) Optimization
2618 Reorder basic blocks and partition into hot and cold sections.
2620 freorder-functions
2621 Common Var(flag_reorder_functions) Optimization
2622 Reorder functions to improve code placement.
2624 frerun-cse-after-loop
2625 Common Var(flag_rerun_cse_after_loop) Optimization
2626 Add a common subexpression elimination pass after loop optimizations.
2628 frerun-loop-opt
2629 Common Ignore
2630 Does nothing.  Preserved for backward compatibility.
2632 frounding-math
2633 Common Var(flag_rounding_math) Optimization SetByCombined
2634 Disable optimizations that assume default FP rounding behavior.
2636 fsched-interblock
2637 Common Var(flag_schedule_interblock) Init(1) Optimization
2638 Enable scheduling across basic blocks.
2640 fsched-pressure
2641 Common Var(flag_sched_pressure) Init(0) Optimization
2642 Enable register pressure sensitive insn scheduling.
2644 fsched-spec
2645 Common Var(flag_schedule_speculative) Init(1) Optimization
2646 Allow speculative motion of non-loads.
2648 fsched-spec-load
2649 Common Var(flag_schedule_speculative_load) Optimization
2650 Allow speculative motion of some loads.
2652 fsched-spec-load-dangerous
2653 Common Var(flag_schedule_speculative_load_dangerous) Optimization
2654 Allow speculative motion of more loads.
2656 fsched-verbose=
2657 Common RejectNegative Joined UInteger Var(sched_verbose_param) Init(1)
2658 -fsched-verbose=<number>        Set the verbosity level of the scheduler.
2660 fsched2-use-superblocks
2661 Common Var(flag_sched2_use_superblocks) Optimization
2662 If scheduling post reload, do superblock scheduling.
2664 fsched2-use-traces
2665 Common Ignore
2666 Does nothing.  Preserved for backward compatibility.
2668 fschedule-insns
2669 Common Var(flag_schedule_insns) Optimization
2670 Reschedule instructions before register allocation.
2672 fschedule-insns2
2673 Common Var(flag_schedule_insns_after_reload) Optimization
2674 Reschedule instructions after register allocation.
2676 ; This flag should be on when a target implements non-trivial
2677 ; scheduling hooks, maybe saving some information for its own sake.
2678 ; On IA64, for example, this is used for correct bundling.
2679 fselective-scheduling
2680 Common Var(flag_selective_scheduling) Optimization
2681 Schedule instructions using selective scheduling algorithm.
2683 fselective-scheduling2
2684 Common Var(flag_selective_scheduling2) Optimization
2685 Run selective scheduling after reload.
2687 fself-test=
2688 Common Undocumented Joined Var(flag_self_test)
2689 Run self-tests, using the given path to locate test files.
2691 fsel-sched-pipelining
2692 Common Var(flag_sel_sched_pipelining) Init(0) Optimization
2693 Perform software pipelining of inner loops during selective scheduling.
2695 fsel-sched-pipelining-outer-loops
2696 Common Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
2697 Perform software pipelining of outer loops during selective scheduling.
2699 fsel-sched-reschedule-pipelined
2700 Common Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
2701 Reschedule pipelined regions without pipelining.
2703 fsemantic-interposition
2704 Common Var(flag_semantic_interposition) Init(1) Optimization
2705 Allow interposing function (or variables) by ones with different semantics (or initializer) respectively by dynamic linker.
2707 ; sched_stalled_insns means that insns can be moved prematurely from the queue
2708 ; of stalled insns into the ready list.
2709 fsched-stalled-insns
2710 Common Var(flag_sched_stalled_insns) Optimization UInteger
2711 Allow premature scheduling of queued insns.
2713 fsched-stalled-insns=
2714 Common RejectNegative Joined UInteger Optimization
2715 -fsched-stalled-insns=<number>  Set number of queued insns that can be prematurely scheduled.
2717 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
2718 ; be examined for a dependency on a stalled insn that is candidate for
2719 ; premature removal from the queue of stalled insns into the ready list (has
2720 ; an effect only if the flag 'sched_stalled_insns' is set).
2721 fsched-stalled-insns-dep
2722 Common Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
2723 Set dependence distance checking in premature scheduling of queued insns.
2725 fsched-stalled-insns-dep=
2726 Common RejectNegative Joined UInteger Optimization
2727 -fsched-stalled-insns-dep=<number>      Set dependence distance checking in premature scheduling of queued insns.
2729 fsched-group-heuristic
2730 Common Var(flag_sched_group_heuristic) Init(1) Optimization
2731 Enable the group heuristic in the scheduler.
2733 fsched-critical-path-heuristic
2734 Common Var(flag_sched_critical_path_heuristic) Init(1) Optimization
2735 Enable the critical path heuristic in the scheduler.
2737 fsched-spec-insn-heuristic
2738 Common Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
2739 Enable the speculative instruction heuristic in the scheduler.
2741 fsched-rank-heuristic
2742 Common Var(flag_sched_rank_heuristic) Init(1) Optimization
2743 Enable the rank heuristic in the scheduler.
2745 fsched-last-insn-heuristic
2746 Common Var(flag_sched_last_insn_heuristic) Init(1) Optimization
2747 Enable the last instruction heuristic in the scheduler.
2749 fsched-dep-count-heuristic
2750 Common Var(flag_sched_dep_count_heuristic) Init(1) Optimization
2751 Enable the dependent count heuristic in the scheduler.
2753 fsection-anchors
2754 Common Var(flag_section_anchors) Optimization
2755 Access data in the same section from shared anchor points.
2757 fsee
2758 Common Ignore
2759 Does nothing.  Preserved for backward compatibility.
2761 fzee
2762 Common Ignore
2763 Does nothing.  Preserved for backward compatibility.
2765 free
2766 Common Var(flag_ree) Init(0) Optimization
2767 Turn on Redundant Extensions Elimination pass.
2769 fshow-column
2770 Common Var(flag_show_column) Init(1)
2771 Show column numbers in diagnostics, when available.  Default on.
2773 fshrink-wrap
2774 Common Var(flag_shrink_wrap) Optimization
2775 Emit function prologues only before parts of the function that need it,
2776 rather than at the top of the function.
2778 fshrink-wrap-separate
2779 Common Var(flag_shrink_wrap_separate) Init(1) Optimization
2780 Shrink-wrap parts of the prologue and epilogue separately.
2782 fsignaling-nans
2783 Common Var(flag_signaling_nans) Optimization SetByCombined
2784 Disable optimizations observable by IEEE signaling NaNs.
2786 fsigned-zeros
2787 Common Var(flag_signed_zeros) Init(1) Optimization SetByCombined
2788 Disable floating point optimizations that ignore the IEEE signedness of zero.
2790 fsingle-precision-constant
2791 Common Var(flag_single_precision_constant) Optimization
2792 Convert floating point constants to single precision constants.
2794 fsplit-ivs-in-unroller
2795 Common Var(flag_split_ivs_in_unroller) Init(1) Optimization
2796 Split lifetimes of induction variables when loops are unrolled.
2798 fsplit-stack
2799 Common Var(flag_split_stack) Init(-1)
2800 Generate discontiguous stack frames.
2802 fsplit-wide-types
2803 Common Var(flag_split_wide_types) Optimization
2804 Split wide types into independent registers.
2806 fsplit-wide-types-early
2807 Common Var(flag_split_wide_types_early) Optimization
2808 Split wide types into independent registers earlier.
2810 fssa-backprop
2811 Common Var(flag_ssa_backprop) Init(1) Optimization
2812 Enable backward propagation of use properties at the SSA level.
2814 fssa-phiopt
2815 Common Var(flag_ssa_phiopt) Optimization
2816 Optimize conditional patterns using SSA PHI nodes.
2818 fstdarg-opt
2819 Common Var(flag_stdarg_opt) Init(1) Optimization
2820 Optimize amount of stdarg registers saved to stack at start of function.
2822 fvariable-expansion-in-unroller
2823 Common Var(flag_variable_expansion_in_unroller) Optimization
2824 Apply variable expansion when loops are unrolled.
2826 fstack-check=
2827 Common RejectNegative Joined Optimization
2828 -fstack-check=[no|generic|specific]     Insert stack checking code into the program.
2830 fstack-check
2831 Common Alias(fstack-check=, specific, no)
2832 Insert stack checking code into the program.  Same as -fstack-check=specific.
2834 fstack-clash-protection
2835 Common Var(flag_stack_clash_protection) Optimization
2836 Insert code to probe each page of stack space as it is allocated to protect
2837 from stack-clash style attacks.
2839 fstack-limit
2840 Common Var(common_deferred_options) Defer
2842 fstack-limit-register=
2843 Common RejectNegative Joined Var(common_deferred_options) Defer
2844 -fstack-limit-register=<register>       Trap if the stack goes past <register>.
2846 fstack-limit-symbol=
2847 Common RejectNegative Joined Var(common_deferred_options) Defer
2848 -fstack-limit-symbol=<name>     Trap if the stack goes past symbol <name>.
2850 fstack-protector
2851 Common Var(flag_stack_protect, 1) Init(-1) Optimization
2852 Use propolice as a stack protection method.
2854 fstack-protector-all
2855 Common RejectNegative Var(flag_stack_protect, 2) Init(-1) Optimization
2856 Use a stack protection method for every function.
2858 fstack-protector-strong
2859 Common RejectNegative Var(flag_stack_protect, 3) Init(-1) Optimization
2860 Use a smart stack protection method for certain functions.
2862 fstack-protector-explicit
2863 Common RejectNegative Var(flag_stack_protect, 4) Optimization
2864 Use stack protection method only for functions with the stack_protect attribute.
2866 fstack-usage
2867 Common RejectNegative Var(flag_stack_usage)
2868 Output stack usage information on a per-function basis.
2870 fstrength-reduce
2871 Common Ignore
2872 Does nothing.  Preserved for backward compatibility.
2874 ; Nonzero if we should do (language-dependent) alias analysis.
2875 ; Typically, this analysis will assume that expressions of certain
2876 ; types do not alias expressions of certain other types.  Only used
2877 ; if alias analysis (in general) is enabled.
2878 fstrict-aliasing
2879 Common Var(flag_strict_aliasing) Optimization
2880 Assume strict aliasing rules apply.
2882 fstrict-overflow
2883 Common
2884 Treat signed overflow as undefined.  Negated as -fwrapv -fwrapv-pointer.
2886 fsync-libcalls
2887 Common Var(flag_sync_libcalls) Init(1)
2888 Implement __atomic operations via libcalls to legacy __sync functions.
2890 fsyntax-only
2891 Common Var(flag_syntax_only)
2892 Check for syntax errors, then stop.
2894 ftest-coverage
2895 Common Var(flag_test_coverage)
2896 Create data files needed by \"gcov\".
2898 fthread-jumps
2899 Common Var(flag_thread_jumps) Optimization
2900 Perform jump threading optimizations.
2902 ftime-report
2903 Common Var(time_report)
2904 Report the time taken by each compiler pass.
2906 ftime-report-details
2907 Common Var(time_report_details)
2908 Record times taken by sub-phases separately.
2910 ftls-model=
2911 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2912 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec]      Set the default thread-local storage code generation model.
2914 Enum
2915 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2917 EnumValue
2918 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2920 EnumValue
2921 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2923 EnumValue
2924 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2926 EnumValue
2927 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2929 ftoplevel-reorder
2930 Common Var(flag_toplevel_reorder) Init(2) Optimization
2931 Reorder top level functions, variables, and asms.
2933 ftracer
2934 Common Var(flag_tracer) Optimization
2935 Perform superblock formation via tail duplication.
2937 ftrampolines
2938 Common Var(flag_trampolines) Init(HEAP_TRAMPOLINES_INIT)
2939 For targets that normally need trampolines for nested functions, always
2940 generate them instead of using descriptors.
2942 ftrampoline-impl=
2943 Common Joined RejectNegative Enum(trampoline_impl) Var(flag_trampoline_impl) Init(HEAP_TRAMPOLINES_INIT ? TRAMPOLINE_IMPL_HEAP : TRAMPOLINE_IMPL_STACK)
2944 Whether trampolines are generated in executable memory rather than
2945 executable stack.
2947 Enum
2948 Name(trampoline_impl) Type(enum trampoline_impl) UnknownError(unknown trampoline implementation %qs)
2950 EnumValue
2951 Enum(trampoline_impl) String(stack) Value(TRAMPOLINE_IMPL_STACK)
2953 EnumValue
2954 Enum(trampoline_impl) String(heap) Value(TRAMPOLINE_IMPL_HEAP)
2957 ; Zero means that floating-point math operations cannot generate a
2958 ; (user-visible) trap.  This is the case, for example, in nonstop
2959 ; IEEE 754 arithmetic.
2960 ftrapping-math
2961 Common Var(flag_trapping_math) Init(1) Optimization SetByCombined
2962 Assume floating-point operations can trap.
2964 ftrapv
2965 Common Var(flag_trapv) Optimization
2966 Trap for signed overflow in addition, subtraction and multiplication.
2968 ftree-ccp
2969 Common Var(flag_tree_ccp) Optimization
2970 Enable SSA-CCP optimization on trees.
2972 ftree-bit-ccp
2973 Common Var(flag_tree_bit_ccp) Optimization
2974 Enable SSA-BIT-CCP optimization on trees.
2976 ftree-store-ccp
2977 Common Ignore
2978 Does nothing.  Preserved for backward compatibility.
2980 ftree-ch
2981 Common Var(flag_tree_ch) Optimization
2982 Enable loop header copying on trees.
2984 ftree-coalesce-inlined-vars
2985 Common Ignore RejectNegative
2986 Does nothing.  Preserved for backward compatibility.
2988 ftree-coalesce-vars
2989 Common Var(flag_tree_coalesce_vars) Optimization
2990 Enable SSA coalescing of user variables.
2992 ftree-copyrename
2993 Common Ignore
2994 Does nothing.  Preserved for backward compatibility.
2996 ftree-copy-prop
2997 Common Var(flag_tree_copy_prop) Optimization
2998 Enable copy propagation on trees.
3000 ftree-store-copy-prop
3001 Common Ignore
3002 Does nothing.  Preserved for backward compatibility.
3004 ftree-cselim
3005 Common Var(flag_tree_cselim) Optimization
3006 Transform condition stores into unconditional ones.
3008 ftree-switch-conversion
3009 Common Var(flag_tree_switch_conversion) Optimization
3010 Perform conversions of switch initializations.
3012 ftree-dce
3013 Common Var(flag_tree_dce) Optimization
3014 Enable SSA dead code elimination optimization on trees.
3016 ftree-dominator-opts
3017 Common Var(flag_tree_dom) Optimization
3018 Enable dominator optimizations.
3020 ftree-tail-merge
3021 Common Var(flag_tree_tail_merge) Optimization
3022 Enable tail merging on trees.
3024 ftree-dse
3025 Common Var(flag_tree_dse) Optimization
3026 Enable dead store elimination.
3028 ftree-forwprop
3029 Common Var(flag_tree_forwprop) Init(1) Optimization
3030 Enable forward propagation on trees.
3032 ftree-fre
3033 Common Var(flag_tree_fre) Optimization
3034 Enable Full Redundancy Elimination (FRE) on trees.
3036 foptimize-strlen
3037 Common Var(flag_optimize_strlen) Optimization
3038 Enable string length optimizations on trees.
3040 fisolate-erroneous-paths-dereference
3041 Common Var(flag_isolate_erroneous_paths_dereference) Optimization
3042 Detect paths that trigger erroneous or undefined behavior due to
3043 dereferencing a null pointer.  Isolate those paths from the main control
3044 flow and turn the statement with erroneous or undefined behavior into a trap.
3046 fisolate-erroneous-paths-attribute
3047 Common Var(flag_isolate_erroneous_paths_attribute) Optimization
3048 Detect paths that trigger erroneous or undefined behavior due to a null value
3049 being used in a way forbidden by a returns_nonnull or nonnull
3050 attribute.  Isolate those paths from the main control flow and turn the
3051 statement with erroneous or undefined behavior into a trap.
3053 ftree-loop-distribution
3054 Common Var(flag_tree_loop_distribution) Optimization
3055 Enable loop distribution on trees.
3057 ftree-loop-distribute-patterns
3058 Common Var(flag_tree_loop_distribute_patterns) Optimization
3059 Enable loop distribution for patterns transformed into a library call.
3061 ftree-loop-im
3062 Common Var(flag_tree_loop_im) Init(1) Optimization
3063 Enable loop invariant motion on trees.
3065 ftree-loop-linear
3066 Common Alias(floop-nest-optimize)
3067 Enable loop nest transforms.  Same as -floop-nest-optimize.
3069 ftree-loop-ivcanon
3070 Common Var(flag_tree_loop_ivcanon) Init(1) Optimization
3071 Create canonical induction variables in loops.
3073 ftree-loop-optimize
3074 Common Var(flag_tree_loop_optimize) Init(1) Optimization
3075 Enable loop optimizations on tree level.
3077 ftree-parallelize-loops=
3078 Common Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1) Optimization
3079 -ftree-parallelize-loops=<number>       Enable automatic parallelization of loops.
3081 ftree-phiprop
3082 Common Var(flag_tree_phiprop) Init(1) Optimization
3083 Enable hoisting loads from conditional pointers.
3085 ftree-pre
3086 Common Var(flag_tree_pre) Optimization
3087 Enable SSA-PRE optimization on trees.
3089 ftree-partial-pre
3090 Common Var(flag_tree_partial_pre) Optimization
3091 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination.
3093 ftree-pta
3094 Common Var(flag_tree_pta) Optimization
3095 Perform function-local points-to analysis on trees.
3097 ftree-reassoc
3098 Common Var(flag_tree_reassoc) Init(1) Optimization
3099 Enable reassociation on tree level.
3101 ftree-salias
3102 Common Ignore
3103 Does nothing.  Preserved for backward compatibility.
3105 ftree-sink
3106 Common Var(flag_tree_sink) Optimization
3107 Enable SSA code sinking on trees.
3109 ftree-slsr
3110 Common Var(flag_tree_slsr) Optimization
3111 Perform straight-line strength reduction.
3113 ftree-sra
3114 Common Var(flag_tree_sra) Optimization
3115 Perform scalar replacement of aggregates.
3117 ftree-ter
3118 Common Var(flag_tree_ter) Optimization
3119 Replace temporary expressions in the SSA->normal pass.
3121 ftree-lrs
3122 Common Var(flag_tree_live_range_split) Optimization
3123 Perform live range splitting during the SSA->normal pass.
3125 ftree-vrp
3126 Common Var(flag_tree_vrp) Init(0) Optimization
3127 Perform Value Range Propagation on trees.
3129 fsplit-paths
3130 Common Var(flag_split_paths) Init(0) Optimization
3131 Split paths leading to loop backedges.
3133 funconstrained-commons
3134 Common Var(flag_unconstrained_commons) Optimization
3135 Assume common declarations may be overridden with ones with a larger
3136 trailing array.
3138 funit-at-a-time
3139 Common Var(flag_unit_at_a_time) Init(1)
3140 Compile whole compilation unit at a time.
3142 funreachable-traps
3143 Common Var(flag_unreachable_traps) Optimization
3144 Trap on __builtin_unreachable instead of using it for optimization.
3146 funroll-loops
3147 Common Var(flag_unroll_loops) Optimization EnabledBy(funroll-all-loops)
3148 Perform loop unrolling when iteration count is known.
3150 funroll-all-loops
3151 Common Var(flag_unroll_all_loops) Optimization
3152 Perform loop unrolling for all loops.
3154 funroll-completely-grow-size
3155 Undocumented Var(flag_cunroll_grow_size) Optimization
3156 ; Internal undocumented flag, allow size growth during complete unrolling
3158 ; Nonzero means that loop optimizer may assume that the induction variables
3159 ; that control loops do not overflow and that the loops with nontrivial
3160 ; exit condition are not infinite
3161 funsafe-loop-optimizations
3162 Common Ignore
3163 Does nothing.  Preserved for backward compatibility.
3165 fassociative-math
3166 Common Var(flag_associative_math) SetByCombined Optimization
3167 Allow optimization for floating-point arithmetic which may change the
3168 result of the operation due to rounding.
3170 freciprocal-math
3171 Common Var(flag_reciprocal_math) SetByCombined Optimization
3172 Same as -fassociative-math for expressions which include division.
3174 ; Nonzero means that unsafe floating-point math optimizations are allowed
3175 ; for the sake of speed.  IEEE compliance is not guaranteed, and operations
3176 ; are allowed to assume that their arguments and results are "normal"
3177 ; (e.g., nonnegative for SQRT).
3178 funsafe-math-optimizations
3179 Common Var(flag_unsafe_math_optimizations) Optimization SetByCombined
3180 Allow math optimizations that may violate IEEE or ISO standards.
3182 funswitch-loops
3183 Common Var(flag_unswitch_loops) Optimization
3184 Perform loop unswitching.
3186 fsplit-loops
3187 Common Var(flag_split_loops) Optimization
3188 Perform loop splitting.
3190 fversion-loops-for-strides
3191 Common Var(flag_version_loops_for_strides) Optimization
3192 Version loops based on whether indices have a stride of one.
3194 funwind-tables
3195 Common Var(flag_unwind_tables) Optimization
3196 Just generate unwind tables for exception handling.
3198 fuse-ld=bfd
3199 Common Driver Negative(fuse-ld=gold)
3200 Use the bfd linker instead of the default linker.
3202 fuse-ld=gold
3203 Common Driver Negative(fuse-ld=bfd)
3204 Use the gold linker instead of the default linker.
3206 fuse-ld=lld
3207 Common Driver Negative(fuse-ld=lld)
3208 Use the lld LLVM linker instead of the default linker.
3210 fuse-ld=mold
3211 Common Driver Negative(fuse-ld=mold)
3212 Use the Modern linker (MOLD) linker instead of the default linker.
3214 fuse-linker-plugin
3215 Common Undocumented Var(flag_use_linker_plugin)
3217 ; Positive if we should track variables, negative if we should run
3218 ; the var-tracking pass only to discard debug annotations, zero if
3219 ; we're not to run it.
3220 fvar-tracking
3221 Common Var(flag_var_tracking) PerFunction EnabledBy(fvar-tracking-uninit)
3222 Perform variable tracking.
3224 ; Positive if we should track variables at assignments, negative if
3225 ; we should run the var-tracking pass only to discard debug
3226 ; annotations.
3227 fvar-tracking-assignments
3228 Common Var(flag_var_tracking_assignments) PerFunction
3229 Perform variable tracking by annotating assignments.
3231 ; Nonzero if we should toggle flag_var_tracking_assignments after
3232 ; processing options and computing its default.  */
3233 fvar-tracking-assignments-toggle
3234 Common Var(flag_var_tracking_assignments_toggle) PerFunction
3235 Toggle -fvar-tracking-assignments.
3237 ; Positive if we should track uninitialized variables, negative if
3238 ; we should run the var-tracking pass only to discard debug
3239 ; annotations.
3240 fvar-tracking-uninit
3241 Common Var(flag_var_tracking_uninit) PerFunction
3242 Perform variable tracking and also tag variables that are uninitialized.
3244 ; Alias to enable both -ftree-loop-vectorize and -ftree-slp-vectorize.
3245 ftree-vectorize
3246 Common Var(flag_tree_vectorize) Optimization
3247 Enable vectorization on trees.
3249 ftree-vectorizer-verbose=
3250 Common Joined RejectNegative Ignore
3251 Does nothing.  Preserved for backward compatibility.
3253 ftree-loop-vectorize
3254 Common Var(flag_tree_loop_vectorize) Optimization EnabledBy(ftree-vectorize)
3255 Enable loop vectorization on trees.
3257 ftree-slp-vectorize
3258 Common Var(flag_tree_slp_vectorize) Optimization EnabledBy(ftree-vectorize)
3259 Enable basic block vectorization (SLP) on trees.
3261 fvect-cost-model=
3262 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT) Optimization
3263 -fvect-cost-model=[unlimited|dynamic|cheap|very-cheap]  Specifies the cost model for vectorization.
3265 fsimd-cost-model=
3266 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED) Optimization
3267 -fsimd-cost-model=[unlimited|dynamic|cheap|very-cheap]  Specifies the vectorization cost model for code marked with a simd directive.
3269 Enum
3270 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
3272 EnumValue
3273 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
3275 EnumValue
3276 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
3278 EnumValue
3279 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
3281 EnumValue
3282 Enum(vect_cost_model) String(very-cheap) Value(VECT_COST_MODEL_VERY_CHEAP)
3284 fvect-cost-model
3285 Common Alias(fvect-cost-model=,dynamic,unlimited)
3286 Enables the dynamic vectorizer cost model.  Preserved for backward compatibility.
3288 ftree-vect-loop-version
3289 Common Ignore
3290 Does nothing. Preserved for backward compatibility.
3292 ftree-scev-cprop
3293 Common Var(flag_tree_scev_cprop) Init(1) Optimization
3294 Enable copy propagation of scalar-evolution information.
3296 ftrivial-auto-var-init=
3297 Common Joined RejectNegative Enum(auto_init_type) Var(flag_auto_var_init) Init(AUTO_INIT_UNINITIALIZED) Optimization
3298 -ftrivial-auto-var-init=[uninitialized|pattern|zero]    Add initializations to automatic variables.
3300 Enum
3301 Name(auto_init_type) Type(enum auto_init_type) UnknownError(unrecognized automatic variable initialization type %qs)
3303 EnumValue
3304 Enum(auto_init_type) String(uninitialized) Value(AUTO_INIT_UNINITIALIZED)
3306 EnumValue
3307 Enum(auto_init_type) String(pattern) Value(AUTO_INIT_PATTERN)
3309 EnumValue
3310 Enum(auto_init_type) String(zero) Value(AUTO_INIT_ZERO)
3312 ; -fverbose-asm causes extra commentary information to be produced in
3313 ; the generated assembly code (to make it more readable).  This option
3314 ; is generally only of use to those who actually need to read the
3315 ; generated assembly code (perhaps while debugging the compiler itself).
3316 ; -fno-verbose-asm, the default, causes the extra information
3317 ; to not be added and is useful when comparing two assembler files.
3318 fverbose-asm
3319 Common Var(flag_verbose_asm)
3320 Add extra commentary to assembler output.
3322 fvisibility=
3323 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
3324 -fvisibility=[default|internal|hidden|protected]        Set the default symbol visibility.
3326 Enum
3327 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
3329 EnumValue
3330 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
3332 EnumValue
3333 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
3335 EnumValue
3336 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
3338 EnumValue
3339 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
3341 fvtable-verify=
3342 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
3343 Validate vtable pointers before using them.
3345 Enum
3346 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
3348 EnumValue
3349 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
3351 EnumValue
3352 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
3354 EnumValue
3355 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
3357 fvtv-counts
3358 Common Var(flag_vtv_counts)
3359 Output vtable verification counters.
3361 fvtv-debug
3362 Common Var(flag_vtv_debug)
3363 Output vtable verification pointer sets information.
3365 fvpt
3366 Common Var(flag_value_profile_transformations) Optimization
3367 Use expression value profiles in optimizations.
3369 fweb
3370 Common Var(flag_web) Optimization EnabledBy(funroll-loops)
3371 Construct webs and split unrelated uses of single variable.
3373 ftree-builtin-call-dce
3374 Common Var(flag_tree_builtin_call_dce) Init(0) Optimization
3375 Enable conditional dead code elimination for builtin calls.
3377 fwhole-program
3378 Common Var(flag_whole_program) Init(0)
3379 Perform whole program optimizations.
3381 fwrapv-pointer
3382 Common Var(flag_wrapv_pointer) Optimization
3383 Assume pointer overflow wraps around.
3385 fwrapv
3386 Common Var(flag_wrapv) Optimization
3387 Assume signed arithmetic overflow wraps around.
3389 fzero-initialized-in-bss
3390 Common Var(flag_zero_initialized_in_bss) Init(1)
3391 Put zero initialized data in the bss section.
3393 fzero-call-used-regs=
3394 Common RejectNegative Joined
3395 Clear call-used registers upon function return.
3398 Common Driver RejectNegative JoinedOrMissing
3399 Generate debug information in default format.
3401 gas-loc-support
3402 Common Driver Var(dwarf2out_as_loc_support)
3403 Assume assembler support for (DWARF2+) .loc directives.
3405 gas-locview-support
3406 Common Driver Var(dwarf2out_as_locview_support)
3407 Assume assembler support for view in (DWARF2+) .loc directives.
3409 gcodeview
3410 Common Driver JoinedOrMissing
3411 Generate debug information in CodeView format.
3413 gcoff
3414 Common Driver WarnRemoved
3415 Does nothing.  Preserved for backward compatibility.
3417 gcoff1
3418 Common Driver WarnRemoved
3419 Does nothing.  Preserved for backward compatibility.
3421 gcoff2
3422 Common Driver WarnRemoved
3423 Does nothing.  Preserved for backward compatibility.
3425 gcoff3
3426 Common Driver WarnRemoved
3427 Does nothing.  Preserved for backward compatibility.
3429 gcolumn-info
3430 Common Driver Var(debug_column_info,1) Init(1)
3431 Record DW_AT_decl_column and DW_AT_call_column in DWARF.
3433 ; The CTF generation process feeds off DWARF dies.  This option implicitly
3434 ; updates the debug_info_level to DINFO_LEVEL_NORMAL.
3435 gctf
3436 Common Driver RejectNegative JoinedOrMissing
3437 Generate CTF debug information at default level.
3439 gbtf
3440 Common Driver RejectNegative JoinedOrMissing
3441 Generate BTF debug information at default level.
3443 gdwarf
3444 Common Driver JoinedOrMissing RejectNegative
3445 Generate debug information in default version of DWARF format.
3447 gdwarf-
3448 Common Driver Joined UInteger Var(dwarf_version) Init(DWARF_VERSION_DEFAULT) RejectNegative
3449 Generate debug information in DWARF v2 (or later) format.
3451 gdwarf32
3452 Common Driver Var(dwarf_offset_size,4) Init(4) RejectNegative
3453 Use 32-bit DWARF format when emitting DWARF debug information.
3455 gdwarf64
3456 Common Driver Var(dwarf_offset_size,8) RejectNegative
3457 Use 64-bit DWARF format when emitting DWARF debug information.
3459 ggdb
3460 Common Driver JoinedOrMissing RejectNegative
3461 Generate debug information in default extended format.
3463 ginline-points
3464 Common Driver Var(debug_inline_points)
3465 Generate extended entry point information for inlined functions.
3467 ginternal-reset-location-views
3468 Common Driver Var(debug_internal_reset_location_views) Init(2)
3469 Compute locview reset points based on insn length estimates.
3471 gno-
3472 RejectNegative Joined Undocumented
3473 ; Catch the gno- prefix, so it doesn't backtrack to g<level>.
3475 gno-pubnames
3476 Common Driver Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
3477 Don't generate DWARF pubnames and pubtypes sections.
3479 gpubnames
3480 Common Driver Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
3481 Generate DWARF pubnames and pubtypes sections.
3483 ggnu-pubnames
3484 Common Driver Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
3485 Generate DWARF pubnames and pubtypes sections with GNU extensions.
3487 grecord-gcc-switches
3488 Common Driver Var(dwarf_record_gcc_switches) Init(1)
3489 Record gcc command line switches in DWARF DW_AT_producer.
3491 gsplit-dwarf
3492 Common Driver Var(dwarf_split_debug_info) Init(0)
3493 Generate debug information in separate .dwo files.
3495 gstabs
3496 Common Driver WarnRemoved
3497 Does nothing.  Preserved for backward compatibility.
3499 gstabs+
3500 Common Driver WarnRemoved
3501 Does nothing.  Preserved for backward compatibility.
3503 gstatement-frontiers
3504 Common Driver Var(debug_nonbind_markers_p) PerFunction
3505 Emit progressive recommended breakpoint locations.
3507 gstrict-dwarf
3508 Common Driver Var(dwarf_strict) Init(0)
3509 Don't emit DWARF additions beyond selected version.
3511 gdescribe-dies
3512 Common Driver Var(flag_describe_dies) Init(0)
3513 Add description attributes to some DWARF DIEs that have no name attribute.
3515 gtoggle
3516 Common Driver Var(flag_gtoggle)
3517 Toggle debug information generation.
3519 gvariable-location-views
3520 Common Driver Var(debug_variable_location_views, 1)
3521 Augment variable location lists with progressive views.
3523 gvariable-location-views=incompat5
3524 Common Driver RejectNegative Var(debug_variable_location_views, -1) Init(2)
3526 gvms
3527 Common Driver JoinedOrMissing RejectNegative
3528 Generate debug information in VMS format.
3530 gxcoff
3531 Common Driver WarnRemoved
3532 Does nothing.  Preserved for backward compatibility.
3534 gxcoff+
3535 Common Driver JoinedOrMissing  WarnRemoved
3536 Does nothing.  Preserved for backward compatibility.
3538 Enum
3539 Name(compressed_debug_sections) Type(int)
3541 ; Since -gz= is completely handled in specs, the values aren't used and we
3542 ; assign arbitrary constants.
3543 EnumValue
3544 Enum(compressed_debug_sections) String(none) Value(0)
3546 EnumValue
3547 Enum(compressed_debug_sections) String(zlib) Value(1)
3549 EnumValue
3550 Enum(compressed_debug_sections) String(zstd) Value(2)
3552 EnumValue
3553 Enum(compressed_debug_sections) String(zlib-gnu) Value(3)
3556 Common Driver
3557 Generate compressed debug sections.
3560 Common Driver RejectNegative Joined Enum(compressed_debug_sections)
3561 -gz=<format>    Generate compressed debug sections in format <format>.
3564 Driver Joined Separate
3566 iplugindir=
3567 Common Joined Var(plugindir_string) Init(0)
3568 -iplugindir=<dir>       Set <dir> to be the default plugin directory.
3570 imultiarch
3571 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
3572 -imultiarch <dir>       Set <dir> to be the multiarch include subdirectory.
3575 Driver Joined Separate
3578 Driver
3580 no-canonical-prefixes
3581 Driver
3583 nodefaultlibs
3584 Driver
3586 nostartfiles
3587 Driver
3589 nolibc
3590 Driver
3592 nostdlib
3593 Driver
3595 nostdlib++
3596 Driver
3599 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
3600 -o <file>       Place output into <file>.
3603 Common Var(profile_flag)
3604 Enable function profiling.
3606 pass-exit-codes
3607 Driver Var(pass_exit_codes)
3609 pedantic
3610 Common Alias(Wpedantic)
3612 pedantic-errors
3613 Common Var(flag_pedantic_errors)
3614 Like -pedantic but issue them as errors.
3617 Driver
3619 pipe
3620 Driver Var(use_pipes)
3622 print-file-name=
3623 Driver JoinedOrMissing Var(print_file_name)
3625 print-libgcc-file-name
3626 Driver
3628 print-multi-directory
3629 Driver Var(print_multi_directory)
3631 print-multi-lib
3632 Driver Var(print_multi_lib)
3634 print-multi-os-directory
3635 Driver Var(print_multi_os_directory)
3637 print-multiarch
3638 Driver Var(print_multiarch)
3640 print-prog-name=
3641 Driver JoinedOrMissing Var(print_prog_name)
3643 print-search-dirs
3644 Driver Var(print_search_dirs)
3646 print-sysroot
3647 Driver Var(print_sysroot)
3649 print-sysroot-headers-suffix
3650 Driver Var(print_sysroot_headers_suffix)
3652 quiet
3653 Common Var(quiet_flag) RejectDriver
3654 Do not display functions compiled or elapsed time.
3657 Driver
3660 Driver
3662 save-temps
3663 Driver
3665 save-temps=
3666 Driver Joined
3669 Driver
3671 time
3672 Driver Var(report_times)
3674 time=
3675 Driver JoinedOrMissing
3678 Driver Joined Separate
3680 undef
3681 Driver
3682 ; C option, but driver must not handle as "-u ndef".
3685 Common Driver Var(verbose_flag)
3686 Enable verbose output.
3688 version
3689 Common Var(version_flag) RejectDriver
3690 Display the compiler's version.
3693 Common Var(inhibit_warnings)
3694 Suppress warnings.
3696 wrapper
3697 Driver Separate Var(wrapper_string)
3700 Driver Joined Separate
3702 shared
3703 Driver RejectNegative Negative(static-pie)
3704 Create a shared library.
3706 shared-libgcc
3707 Driver
3709 specs
3710 Driver Separate Alias(specs=)
3712 specs=
3713 Driver Joined
3715 static
3716 Driver
3718 static-libgcc
3719 Driver
3721 static-libgfortran
3722 Driver
3723 ; Documented for Fortran, but always accepted by driver.
3725 static-libgm2
3726 Driver
3727 ; Documented for Modula-2, but always accepted by driver.
3729 static-libphobos
3730 Driver
3731 ; Documented for D, but always accepted by driver.
3733 static-libquadmath
3734 Driver
3735 ; Documented for Fortran, but always accepted by driver.
3737 static-libstdc++
3738 Driver
3740 static-libgo
3741 Driver
3742 ; Documented for Go, but always accepted by driver.
3744 static-libasan
3745 Driver
3747 static-libhwasan
3748 Driver
3750 static-libtsan
3751 Driver
3753 static-liblsan
3754 Driver
3756 static-libubsan
3757 Driver
3759 symbolic
3760 Driver
3762 no-pie
3763 Driver RejectNegative Negative(shared)
3764 Don't create a dynamically linked position independent executable.
3767 Driver RejectNegative Negative(no-pie)
3768 Create a dynamically linked position independent executable.
3770 static-pie
3771 Driver RejectNegative Negative(pie)
3772 Create a static position independent executable.
3775 Driver Joined Separate
3777 fipa-ra
3778 Common Var(flag_ipa_ra) Optimization
3779 Use caller save register across calls if possible.
3781 ; This comment is to ensure we retain the blank line above.