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[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) 2003-2020 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 incrmeental 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 ; Language specific warning pass for unused results.
63 Variable
64 bool flag_warn_unused_result = false
66 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
67 Variable
68 int flag_generate_lto
70 ; Nonzero if we should write GIMPLE bytecode for offload compilation.
71 Variable
72 int flag_generate_offload = 0
74 ; Nonzero means we should be saving declaration info into a .X file.
75 Variable
76 int flag_gen_aux_info = 0
78 ; Nonzero if we are compiling code for a shared library, zero for
79 ; executable.
80 Variable
81 int flag_shlib
83 ; These two are really VEC(char_p,heap) *.
85 Variable
86 void *flag_instrument_functions_exclude_functions
88 Variable
89 void *flag_instrument_functions_exclude_files
91 ; Generic structs (e.g. templates not explicitly specialized)
92 ; may not have a compilation unit associated with them, and so
93 ; may need to be treated differently from ordinary structs.
95 ; Structs only handled by reference (indirectly), will also usually
96 ; not need as much debugging information.
98 Variable
99 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
101 Variable
102 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
104 ; True if we should exit after parsing options.
105 Variable
106 bool exit_after_options
108 ; Type(s) of debugging information we are producing (if any).  See
109 ; flag-types.h for the definitions of the different possible types of
110 ; debugging information.
111 Variable
112 enum debug_info_type write_symbols = NO_DEBUG
114 ; Level of debugging information we are producing.  See flag-types.h
115 ; for the definitions of the different possible levels.
116 Variable
117 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
119 ; Nonzero means use GNU-only extensions in the generated symbolic
120 ; debugging information.  Currently, this only has an effect when
121 ; write_symbols is set to DBX_DEBUG or XCOFF_DEBUG.
122 Variable
123 bool use_gnu_debug_info_extensions
125 ; Original value of maximum field alignment in bytes, specified via
126 ; -fpack-struct=<value>.
127 Variable
128 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
130 ; Type of stack check.
131 Variable
132 enum stack_check_type flag_stack_check = NO_STACK_CHECK
134 ; True if stack usage information needs to be computed.
135 Variable
136 bool flag_stack_usage_info = false
138 ; -dA causes debug commentary information to be produced in
139 ; the generated assembly code (to make it more readable).  This option
140 ; is generally only of use to those who actually need to read the
141 ; generated assembly code (perhaps while debugging the compiler itself).
142 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
143 ; to be a catchall for printing debug information in the assembler file.
144 Variable
145 int flag_debug_asm
147 ; How many NOP insns to place at each function entry by default
148 Variable
149 HOST_WIDE_INT function_entry_patch_area_size
151 ; And how far the real asm entry point is into this area
152 Variable
153 HOST_WIDE_INT function_entry_patch_area_start
155 ; Balance between GNAT encodings and standard DWARF to emit.
156 Variable
157 enum dwarf_gnat_encodings gnat_encodings = DWARF_GNAT_ENCODINGS_DEFAULT
159 ; -dP causes the rtl to be emitted as a comment in assembly.
160 Variable
161 int flag_dump_rtl_in_asm
163 ; Whether -da was passed (used only in handle_common_deferred_options).
164 Variable
165 bool flag_dump_all_passed
167 ; Other flags saying which kinds of debugging dump have been requested.
169 Variable
170 int rtl_dump_and_exit
172 Variable
173 int flag_print_asm_name
175 ; Name of top-level original source file (what was input to cpp).
176 ; This comes from the #-command at the beginning of the actual input.
177 ; If there isn't any there, then this is the cc1 input file name.
178 Variable
179 const char *main_input_filename
181 ; Pointer to base name in main_input_filename, with directories and a
182 ; single final extension removed, and the length of this base
183 ; name.
185 Variable
186 const char *main_input_basename
188 Variable
189 int main_input_baselength
191 ; Which options have been printed by --help.
192 Variable
193 char *help_printed
195 ; Which enums have been printed by --help.  0 = not printed, no
196 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
197 ; = printed.
198 Variable
199 char *help_enum_printed
201 ; The number of columns for --help output.
202 Variable
203 unsigned int help_columns
205 ; Whether this options structure has been through finish_options
206 Variable
207 bool flag_opts_finished
209 ; What the sanitizer should instrument
210 Variable
211 unsigned int flag_sanitize
213 ; What sanitizers should recover from errors
214 Variable
215 unsigned int flag_sanitize_recover = (SANITIZE_UNDEFINED | SANITIZE_UNDEFINED_NONDEFAULT | SANITIZE_KERNEL_ADDRESS) & ~(SANITIZE_UNREACHABLE | SANITIZE_RETURN)
217 ; What the coverage sanitizers should instrument
218 Variable
219 unsigned int flag_sanitize_coverage
221 ; Flag whether a prefix has been added to dump_base_name
222 Variable
223 bool dump_base_name_prefixed = false
225 ; Flag whether HSA generation has been explicitely disabled
226 Variable
227 bool flag_disable_hsa = false
230 Driver
232 -assemble
233 Driver Alias(S)
235 -compile
236 Driver Alias(c)
238 -completion=
239 Common Driver Joined Undocumented
240 Provide bash completion for options starting with provided string.
242 -coverage
243 Driver Alias(coverage)
245 -debug
246 Common Alias(g)
248 -dump
249 Common Separate Alias(d)
251 -dump=
252 Common Joined Alias(d)
254 -dumpbase
255 Common Separate Alias(dumpbase)
257 -dumpdir
258 Common Separate Alias(dumpdir)
260 -entry
261 Driver Separate Alias(e)
263 -entry=
264 Driver Joined Alias(e)
266 -extra-warnings
267 Common Warning Alias(Wextra)
269 -for-assembler
270 Driver Separate Alias(Xassembler)
272 -for-assembler=
273 Driver JoinedOrMissing Alias(Xassembler)
275 -for-linker
276 Driver Separate Alias(Xlinker)
278 -for-linker=
279 Driver JoinedOrMissing Alias(Xlinker)
281 -force-link
282 Driver Separate Alias(u)
284 -force-link=
285 Driver Joined Alias(u)
287 -help
288 Common Driver Var(help_flag)
289 Display this information.
291 -help=
292 Common Driver Report Joined
293 --help=<class>  Display descriptions of a specific class of options.  <class> is one or more of optimizers, target, warnings, undocumented, params.
295 -language
296 Driver Separate Alias(x)
298 -language=
299 Driver Joined Alias(x)
301 -library-directory
302 Driver Separate Alias(L)
304 -library-directory=
305 Driver Joined Alias(L)
307 -no-canonical-prefixes
308 Driver Alias(no-canonical-prefixes)
310 -no-standard-libraries
311 Driver Alias(nostdlib)
313 -no-sysroot-suffix
314 Driver Var(no_sysroot_suffix)
316 -no-warnings
317 Common Alias(w)
319 -optimize
320 Common Alias(O)
322 -output
323 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
325 -output=
326 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
328 -pass-exit-codes
329 Driver Alias(pass-exit-codes)
331 -pedantic
332 Common Alias(Wpedantic)
334 -pedantic-errors
335 Common Alias(pedantic-errors)
337 -pie
338 Driver Alias(pie)
340 -static-pie
341 Driver Alias(static-pie)
343 -pipe
344 Driver Alias(pipe)
346 -prefix
347 Driver Separate Alias(B)
349 -prefix=
350 Driver JoinedOrMissing Alias(B)
352 -preprocess
353 Driver Alias(E)
355 -print-file-name
356 Driver Separate Alias(print-file-name=)
358 -print-file-name=
359 Driver JoinedOrMissing Alias(print-file-name=)
361 -print-libgcc-file-name
362 Driver Alias(print-libgcc-file-name)
364 -print-multi-directory
365 Driver Alias(print-multi-directory)
367 -print-multi-lib
368 Driver Alias(print-multi-lib)
370 -print-multi-os-directory
371 Driver Alias(print-multi-os-directory)
373 -print-multiarch
374 Driver Alias(print-multiarch)
376 -print-prog-name
377 Driver Separate Alias(print-prog-name=)
379 -print-prog-name=
380 Driver JoinedOrMissing Alias(print-prog-name=)
382 -print-search-dirs
383 Driver Alias(print-search-dirs)
385 -print-sysroot
386 Driver Alias(print-sysroot)
388 -print-sysroot-headers-suffix
389 Driver Alias(print-sysroot-headers-suffix)
391 -profile
392 Common Alias(p)
394 -save-temps
395 Driver Alias(save-temps)
397 -shared
398 Driver Alias(shared)
400 -specs
401 Driver Separate Alias(specs=)
403 -specs=
404 Driver Joined Alias(specs=)
406 -static
407 Driver Alias(static)
409 -symbolic
410 Driver Alias(symbolic)
412 -target-help
413 Common Driver
414 Alias for --help=target.
416 -time
417 Driver Alias(time)
419 -verbose
420 Driver Alias(v)
422 ;; The driver used to convert options such as --help into forms such
423 ;; as -fhelp; the following four entries are for compatibility with
424 ;; any direct uses of those (undocumented) -f forms
425 fhelp
426 Common Driver Alias(-help)
428 fhelp=
429 Common Driver Joined Alias(-help=)
431 ftarget-help
432 Common Driver Alias(-target-help)
434 fversion
435 Common Driver Alias(-version)
437 -sysroot
438 Driver Separate Alias(-sysroot=)
440 -sysroot=
441 Driver JoinedOrMissing
443 -version
444 Common Driver
447 Driver Joined Separate
450 Driver
453 Driver Joined Separate
456 Driver
459 Common JoinedOrMissing Optimization
460 -O<number>      Set optimization level to <number>.
463 Common Optimization
464 Optimize for space rather than speed.
466 Ofast
467 Common Optimization
468 Optimize for speed disregarding exact standards compliance.
471 Common Optimization
472 Optimize for debugging experience rather than speed or size.
475 Driver
478 Driver Negative(Qy)
481 Driver Negative(Qn)
484 Driver Joined Separate
487 Driver
490 Driver Joined Separate
492 Tbss
493 Driver Separate
495 Tbss=
496 Driver Joined
498 Tdata
499 Driver Separate
501 Tdata=
502 Driver Joined
504 Ttext
505 Driver Separate
507 Ttext=
508 Driver Joined
511 Common RejectNegative Warning Alias(Wextra)
512 This switch is deprecated; use -Wextra instead.
515 Driver JoinedOrMissing RejectNegative
518 Driver JoinedOrMissing RejectNegative
521 Driver JoinedOrMissing RejectNegative
523 Waggregate-return
524 Common Var(warn_aggregate_return) Warning
525 Warn about returning structures, unions or arrays.
527 Waggressive-loop-optimizations
528 Common Var(warn_aggressive_loop_optimizations) Init(1) Warning
529 Warn if a loop with constant number of iterations triggers undefined behavior.
531 Warray-bounds
532 Common Var(warn_array_bounds) Warning
533 Warn if an array is accessed out of bounds.
535 Warray-bounds=
536 Common Joined RejectNegative UInteger Var(warn_array_bounds) Warning IntegerRange(0, 2)
537 Warn if an array is accessed out of bounds.
539 Wattributes
540 Common Var(warn_attributes) Init(1) Warning
541 Warn about inappropriate attribute usage.
543 Wattribute-alias
544 Common Alias(Wattribute_alias=, 1, 0) Warning
545 Warn about type safety and similar errors and mismatches in declarations with alias attributes.
547 Wattribute-alias=
548 Common Joined RejectNegative UInteger Var(warn_attribute_alias) Init(1) Warning IntegerRange(0, 2)
549 Warn about type safety and similar errors and mismatches in declarations with alias attributes.
551 Wcannot-profile
552 Common Var(warn_cannot_profile) Init(1) Warning
553 Warn when profiling instrumentation was requested, but could not be applied to
554 a certain function.
556 Wcast-align
557 Common Var(warn_cast_align) Warning
558 Warn about pointer casts which increase alignment.
560 Wcast-align=strict
561 Common Var(warn_cast_align,2) Warning
562 Warn about pointer casts which increase alignment.
564 Wcpp
565 Common Var(warn_cpp) Init(1) Warning
566 Warn when a #warning directive is encountered.
568 Wattribute-warning
569 Common Var(warn_attribute_warning) Init(1) Warning
570 Warn about uses of __attribute__((warning)) declarations.
572 Wdeprecated
573 Common Var(warn_deprecated) Init(1) Warning
574 Warn if a deprecated compiler feature, class, method, or field is used.
576 Wdeprecated-declarations
577 Common Var(warn_deprecated_decl) Init(1) Warning
578 Warn about uses of __attribute__((deprecated)) declarations.
580 Wdisabled-optimization
581 Common Var(warn_disabled_optimization) Warning
582 Warn when an optimization pass is disabled.
584 Werror
585 Common Var(warnings_are_errors)
586 Treat all warnings as errors.
588 Werror=
589 Common Joined
590 Treat specified warning as error.
592 Wextra
593 Common Var(extra_warnings) Warning
594 Print extra (possibly unwanted) warnings.
596 Wfatal-errors
597 Common Var(flag_fatal_errors)
598 Exit on the first error occurred.
600 Wframe-larger-than=
601 Common RejectNegative Joined Host_Wide_Int ByteSize Warning Var(warn_frame_larger_than_size) Init(HOST_WIDE_INT_MAX)
602 -Wframe-larger-than=<byte-size> Warn if a function's stack frame requires in excess of <byte-size>.
604 Wno-frame-larger-than
605 Common Alias(Wframe-larger-than=,18446744073709551615EiB,none) Warning
606 Disable -Wframe-larger-than= warning.  Equivalent to -Wframe-larger-than=<SIZE_MAX> or larger.
608 Wfree-nonheap-object
609 Common Var(warn_free_nonheap_object) Init(1) Warning
610 Warn when attempting to free a non-heap object.
612 Whsa
613 Common Var(warn_hsa) Init(1) Warning
614 Warn when a function cannot be expanded to HSAIL.
616 Wimplicit-fallthrough
617 Common Alias(Wimplicit-fallthrough=,3,0) Warning
619 Wimplicit-fallthrough=
620 Common Var(warn_implicit_fallthrough) RejectNegative Joined UInteger Warning IntegerRange(0, 5)
621 Warn when a switch case falls through.
623 Winline
624 Common Var(warn_inline) Warning Optimization
625 Warn when an inlined function cannot be inlined.
627 Winvalid-memory-model
628 Common Var(warn_invalid_memory_model) Init(1) Warning
629 Warn when an atomic memory model parameter is known to be outside the valid range.
631 Wlarger-than-
632 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
634 Wlarger-than=
635 Common RejectNegative Joined Host_Wide_Int ByteSize Warning Var(warn_larger_than_size) Init(HOST_WIDE_INT_MAX)
636 -Wlarger-than=<byte-size>       Warn if an object's size exceeds <byte-size>.
638 Wno-larger-than
639 Common Alias(Wlarger-than=,18446744073709551615EiB,none) Warning
640 Disable -Wlarger-than= warning.  Equivalent to -Wlarger-than=<SIZE_MAX> or larger.
642 Wnonnull-compare
643 Var(warn_nonnull_compare) Warning
644 Warn if comparing pointer parameter with nonnull attribute with NULL.
646 Wnull-dereference
647 Common Var(warn_null_dereference) Warning
648 Warn if dereferencing a NULL pointer may lead to erroneous or undefined behavior.
650 Wunsafe-loop-optimizations
651 Common Ignore Warning
652 Does nothing. Preserved for backward compatibility.
654 Wmissing-noreturn
655 Common Warning Alias(Wsuggest-attribute=noreturn)
657 Wodr
658 Common Var(warn_odr_violations) Init(1) Warning
659 Warn about some C++ One Definition Rule violations during link time optimization.
661 Woverflow
662 Common Var(warn_overflow) Init(1) Warning
663 Warn about overflow in arithmetic expressions.
665 Wlto-type-mismatch
666 Common Var(warn_lto_type_mismatch) Init(1) Warning
667 During link time optimization warn about mismatched types of global declarations.
669 Wpacked
670 Common Var(warn_packed) Warning
671 Warn when the packed attribute has no effect on struct layout.
673 Wpadded
674 Common Var(warn_padded) Warning
675 Warn when padding is required to align structure members.
677 Wpedantic
678 Common Var(pedantic) Init(0) Warning
679 Issue warnings needed for strict compliance to the standard.
681 Wreturn-local-addr
682 Common Var(warn_return_local_addr) Init(1) Warning
683 Warn about returning a pointer/reference to a local or temporary variable.
685 Wshadow
686 Common Var(warn_shadow) Warning
687 Warn when one variable shadows another.  Same as -Wshadow=global.
689 Wshadow=global
690 Common Warning Alias(Wshadow)
691 Warn when one variable shadows another (globally).
693 Wshadow=local
694 Common Var(warn_shadow_local) Warning EnabledBy(Wshadow)
695 Warn when one local variable shadows another local variable or parameter.
697 Wshadow-local
698 Common Warning Undocumented Alias(Wshadow=local)
700 Wshadow=compatible-local
701 Common Var(warn_shadow_compatible_local) Warning EnabledBy(Wshadow=local)
702 Warn when one local variable shadows another local variable or parameter of compatible type.
704 Wshadow-compatible-local
705 Common Warning Undocumented Alias(Wshadow=compatible-local)
707 Wstack-protector
708 Common Var(warn_stack_protect) Warning
709 Warn when not issuing stack smashing protection for some reason.
711 Wstack-usage=
712 Common Joined RejectNegative Host_Wide_Int ByteSize Var(warn_stack_usage) Warning Init(HOST_WIDE_INT_MAX)
713 -Wstack-usage=<byte-size>       Warn if stack usage might exceed <byte-size>.
715 Wno-stack-usage
716 Common Alias(Wstack-usage=,18446744073709551615EiB,none) Warning
717 Disable Wstack-usage= warning.  Equivalent to Wstack-usage=<SIZE_MAX> or larger.
719 Wstrict-aliasing
720 Common Warning
721 Warn about code which might break strict aliasing rules.
723 Wstrict-aliasing=
724 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
725 Warn about code which might break strict aliasing rules.
727 Wstrict-overflow
728 Common Warning
729 Warn about optimizations that assume that signed overflow is undefined.
731 Wstrict-overflow=
732 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
733 Warn about optimizations that assume that signed overflow is undefined.
735 Wsuggest-attribute=cold
736 Common Var(warn_suggest_attribute_cold) Warning
737 Warn about functions which might be candidates for __attribute__((cold)).
739 Wsuggest-attribute=const
740 Common Var(warn_suggest_attribute_const) Warning
741 Warn about functions which might be candidates for __attribute__((const)).
743 Wsuggest-attribute=pure
744 Common Var(warn_suggest_attribute_pure) Warning
745 Warn about functions which might be candidates for __attribute__((pure)).
747 Wsuggest-attribute=noreturn
748 Common Var(warn_suggest_attribute_noreturn) Warning
749 Warn about functions which might be candidates for __attribute__((noreturn)).
751 Wsuggest-attribute=malloc
752 Common Var(warn_suggest_attribute_malloc) Warning
753 Warn about functions which might be candidates for __attribute__((malloc)).
755 Wsuggest-final-types
756 Common Var(warn_suggest_final_types) Warning
757 Warn about C++ polymorphic types where adding final keyword would improve code quality.
759 Wsuggest-final-methods
760 Common Var(warn_suggest_final_methods) Warning
761 Warn about C++ virtual methods where adding final keyword would improve code quality.
763 Wswitch-unreachable
764 Common Var(warn_switch_unreachable) Warning Init(1)
765 Warn about statements between switch's controlling expression and the first
766 case.
768 Wsystem-headers
769 Common Var(warn_system_headers) Warning
770 Do not suppress warnings from system headers.
772 Wtrampolines
773 Common Var(warn_trampolines) Warning
774 Warn whenever a trampoline is generated.
776 Wtype-limits
777 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
778 Warn if a comparison is always true or always false due to the limited range of the data type.
780 Wuninitialized
781 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
782 Warn about uninitialized automatic variables.
784 Wmaybe-uninitialized
785 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
786 Warn about maybe uninitialized automatic variables.
788 Wunreachable-code
789 Common Ignore Warning
790 Does nothing. Preserved for backward compatibility.
792 Wunused
793 Common Var(warn_unused) Init(0) Warning
794 Enable all -Wunused- warnings.
796 Wunused-but-set-parameter
797 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
798 Warn when a function parameter is only set, otherwise unused.
800 Wunused-but-set-variable
801 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
802 Warn when a variable is only set, otherwise unused.
804 Wunused-function
805 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
806 Warn when a function is unused.
808 Wunused-label
809 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
810 Warn when a label is unused.
812 Wunused-parameter
813 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
814 Warn when a function parameter is unused.
816 Wunused-value
817 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
818 Warn when an expression value is unused.
820 Wunused-variable
821 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
822 Warn when a variable is unused.
824 Wcoverage-mismatch
825 Common Var(warn_coverage_mismatch) Init(1) Warning
826 Warn in case profiles in -fprofile-use do not match.
828 Wmissing-profile
829 Common Var(warn_missing_profile) Init(1) Warning
830 Warn in case profiles in -fprofile-use do not exist.
832 Wvector-operation-performance
833 Common Var(warn_vector_operation_performance) Warning
834 Warn when a vector operation is compiled outside the SIMD.
836 Xassembler
837 Driver Separate
839 Xlinker
840 Driver Separate
842 Xpreprocessor
843 Driver Separate
846 Driver
848 aux-info
849 Common Separate Var(aux_info_file_name)
850 -aux-info <file>        Emit declaration information into <file>.
852 aux-info=
853 Common Joined Alias(aux-info)
855 auxbase
856 Common Separate RejectDriver Var(aux_base_name)
858 auxbase-strip
859 Common Separate RejectDriver
861 coverage
862 Driver
865 Driver
868 Common Joined
869 -d<letters>     Enable dumps from specific passes of the compiler.
871 dumpbase
872 Common Separate Var(dump_base_name)
873 -dumpbase <file>        Set the file basename to be used for dumps.
875 dumpdir
876 Common Separate Var(dump_dir_name)
877 -dumpdir <dir>  Set the directory name to be used for dumps.
879 dumpmachine
880 Driver
882 dumpspecs
883 Driver
885 dumpversion
886 Driver
888 dumpfullversion
889 Driver
892 Driver Joined Separate
894 ; This option has historically been passed down to the linker by an
895 ; accident of a %{e*} spec, so ensure it continues to be passed down
896 ; as a single option.  The supported option for this purpose is
897 ; -rdynamic.  See PR 47390.
898 export-dynamic
899 Driver Undocumented
901 ; The version of the C++ ABI in use.  The following values are allowed:
903 ; 0: The version of the ABI believed most conformant with the C++ ABI
904 ;    specification.  This ABI may change as bugs are discovered and fixed.
905 ;    Therefore, 0 will not necessarily indicate the same ABI in different
906 ;    versions of G++.
908 ; 1: The version of the ABI first used in G++ 3.2.  No longer selectable.
910 ; 2: The version of the ABI first used in G++ 3.4, and the default
911 ;    until GCC 4.9.
913 ; 3: The version of the ABI that fixes the missing underscore
914 ;    in template non-type arguments of pointer type.
916 ; 4: The version of the ABI that introduces unambiguous mangling of
917 ;    vector types.  First selectable in G++ 4.5.
919 ; 5: The version of the ABI that ignores attribute const/noreturn
920 ;    in function pointer mangling, and corrects mangling of decltype and
921 ;    function parameters used in other parameters and the return type.
922 ;    First selectable in G++ 4.6.
924 ; 6: The version of the ABI that doesn't promote scoped enums to int and
925 ;    changes the mangling of template argument packs, const/static_cast,
926 ;    prefix ++ and --, and a class scope function used as a template
927 ;    argument.
928 ;    First selectable in G++ 4.7.
930 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
931 ;    corrects the mangling of lambdas in default argument scope.
932 ;    First selectable in G++ 4.8.
934 ; 8: The version of the ABI that corrects the substitution behavior of
935 ;    function types with function-cv-qualifiers.
936 ;    First selectable in G++ 4.9 and default in G++ 5.
938 ; 9: The version of the ABI that corrects the alignment of nullptr_t.
939 ;    First selectable and default in G++ 5.2.
941 ; 10: The version of the ABI that mangles attributes that affect type
942 ;     identity, such as ia32 calling convention attributes (stdcall, etc.)
943 ;     Default in G++ 6 (set in c_common_post_options).
945 ; 11: The version of the ABI that corrects mangling of sizeof... expressions
946 ;     and introduces new inheriting constructor handling.
947 ;     Default in G++ 7.
949 ; 12: Corrects the calling convention for classes with only deleted copy/move
950 ;     constructors and changes passing/returning of empty records.
951 ;     Default in G++ 8.1.
953 ; 13: Fixes the accidental change in 12 to the calling convention for classes
954 ;     with deleted copy constructor and trivial move constructor.
955 ;     Default in G++ 8.2.
956 ; 14: Corrects the mangling of nullptr expression.
957 ;     Default in G++ 10.
959 ; Additional positive integers will be assigned as new versions of
960 ; the ABI become the default version of the ABI.
961 fabi-version=
962 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(0)
963 The version of the C++ ABI in use.
965 faggressive-loop-optimizations
966 Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1)
967 Aggressively optimize loops using language constraints.
969 falign-functions
970 Common Report Var(flag_align_functions) Optimization
971 Align the start of functions.
973 falign-functions=
974 Common RejectNegative Joined Var(str_align_functions) Optimization
976 flimit-function-alignment
977 Common Report Var(flag_limit_function_alignment) Optimization Init(0)
979 falign-jumps
980 Common Report Var(flag_align_jumps) Optimization
981 Align labels which are only reached by jumping.
983 falign-jumps=
984 Common RejectNegative Joined Var(str_align_jumps) Optimization
986 falign-labels
987 Common Report Var(flag_align_labels) Optimization
988 Align all labels.
990 falign-labels=
991 Common RejectNegative Joined Var(str_align_labels) Optimization
993 falign-loops
994 Common Report Var(flag_align_loops) Optimization
995 Align the start of loops.
997 falign-loops=
998 Common RejectNegative Joined Var(str_align_loops) Optimization
1000 fallow-store-data-races
1001 Common Report Var(flag_store_data_races) Optimization
1002 Allow the compiler to introduce new data races on stores.
1004 fanalyzer
1005 Common Var(flag_analyzer)
1006 Enable static analysis pass.
1008 fargument-alias
1009 Common Ignore
1010 Does nothing. Preserved for backward compatibility.
1012 fargument-noalias
1013 Common Ignore
1014 Does nothing. Preserved for backward compatibility.
1016 fargument-noalias-global
1017 Common Ignore
1018 Does nothing. Preserved for backward compatibility.
1020 fargument-noalias-anything
1021 Common Ignore
1022 Does nothing. Preserved for backward compatibility.
1024 fsanitize=
1025 Common Driver Report Joined
1026 Select what to sanitize.
1028 fsanitize-coverage=
1029 Common Report Joined
1030 Select type of coverage sanitization.
1032 fasan-shadow-offset=
1033 Common Joined RejectNegative Var(common_deferred_options) Defer
1034 -fasan-shadow-offset=<number>   Use custom shadow memory offset.
1036 fsanitize-sections=
1037 Common Joined RejectNegative Var(common_deferred_options) Defer
1038 -fsanitize-sections=<sec1,sec2,...>     Sanitize global variables
1039 in user-defined sections.
1041 fsanitize-recover=
1042 Common Report Joined
1043 After diagnosing undefined behavior attempt to continue execution.
1045 fsanitize-recover
1046 Common Report
1047 This switch is deprecated; use -fsanitize-recover= instead.
1049 fsanitize-address-use-after-scope
1050 Common Driver Report Var(flag_sanitize_address_use_after_scope) Init(0)
1052 fsanitize-undefined-trap-on-error
1053 Common Driver Report Var(flag_sanitize_undefined_trap_on_error) Init(0)
1054 Use trap instead of a library function for undefined behavior sanitization.
1056 fasynchronous-unwind-tables
1057 Common Report Var(flag_asynchronous_unwind_tables) Optimization
1058 Generate unwind tables that are exact at each instruction boundary.
1060 fauto-inc-dec
1061 Common Report Var(flag_auto_inc_dec) Init(1) Optimization
1062 Generate auto-inc/dec instructions.
1064 fauto-profile
1065 Common Report Var(flag_auto_profile)
1066 Use sample profile information for call graph node weights. The default
1067 profile file is fbdata.afdo in 'pwd'.
1069 fauto-profile=
1070 Common Joined RejectNegative Var(auto_profile_file)
1071 Use sample profile information for call graph node weights. The profile
1072 file is specified in the argument.
1074 ; -fcheck-bounds causes gcc to generate array bounds checks.
1075 ; For C, C++ and ObjC: defaults off.
1076 ; For Java: defaults to on.
1077 ; For Fortran: defaults to off.
1078 fbounds-check
1079 Common Report Var(flag_bounds_check)
1080 Generate code to check bounds before indexing arrays.
1082 fbranch-count-reg
1083 Common Report Var(flag_branch_on_count_reg) Optimization
1084 Replace add, compare, branch with branch on count register.
1086 fbranch-probabilities
1087 Common Report Var(flag_branch_probabilities) Optimization
1088 Use profiling information for branch probabilities.
1090 fbranch-target-load-optimize
1091 Common Ignore
1092 Does nothing.  Preserved for backward compatibility.
1094 fbranch-target-load-optimize2
1095 Common Ignore
1096 Does nothing.  Preserved for backward compatibility.
1098 fbtr-bb-exclusive
1099 Common Ignore
1100 Does nothing.  Preserved for backward compatibility.
1102 fcallgraph-info
1103 Common Report RejectNegative Var(flag_callgraph_info) Init(NO_CALLGRAPH_INFO);
1104 Output callgraph information on a per-file basis.
1106 fcallgraph-info=
1107 Common Report RejectNegative Joined
1108 Output callgraph information on a per-file basis with decorations.
1110 fcall-saved-
1111 Common Joined RejectNegative Var(common_deferred_options) Defer
1112 -fcall-saved-<register> Mark <register> as being preserved across functions.
1114 fcall-used-
1115 Common Joined RejectNegative Var(common_deferred_options) Defer
1116 -fcall-used-<register>  Mark <register> as being corrupted by function calls.
1118 ; Nonzero for -fcaller-saves: allocate values in regs that need to
1119 ; be saved across function calls, if that produces overall better code.
1120 ; Optional now, so people can test it.
1121 fcaller-saves
1122 Common Report Var(flag_caller_saves) Optimization
1123 Save registers around function calls.
1125 fcheck-data-deps
1126 Common Ignore
1127 This switch is deprecated; do not use.
1129 fcheck-new
1130 Common Var(flag_check_new)
1131 Check the return value of new in C++.
1133 fchecking
1134 Common Var(flag_checking) Init(CHECKING_P ? ENABLE_EXTRA_CHECKING ? 2 : 1 : 0)
1135 Perform internal consistency checkings.
1137 fchecking=
1138 Common Joined RejectNegative UInteger Var(flag_checking)
1139 Perform internal consistency checkings.
1141 fcode-hoisting
1142 Common Report Var(flag_code_hoisting) Optimization
1143 Enable code hoisting.
1145 fcombine-stack-adjustments
1146 Common Report Var(flag_combine_stack_adjustments) Optimization
1147 Looks for opportunities to reduce stack adjustments and stack references.
1149 fcommon
1150 Common Report Var(flag_no_common,0) Init(1)
1151 Put uninitialized globals in the common section.
1153 fcompare-debug
1154 Driver
1155 ; Converted by the driver to -fcompare-debug= options.
1157 fcompare-debug=
1158 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
1159 -fcompare-debug[=<opts>]        Compile with and without e.g. -gtoggle, and compare the final-insns dump.
1161 fcompare-debug-second
1162 Common Driver RejectNegative Var(flag_compare_debug)
1163 Run only the second compilation of -fcompare-debug.
1165 fcompare-elim
1166 Common Report Var(flag_compare_elim_after_reload) Optimization
1167 Perform comparison elimination after register allocation has finished.
1169 fconserve-stack
1170 Common Var(flag_conserve_stack) Optimization
1171 Do not perform optimizations increasing noticeably stack usage.
1173 fcprop-registers
1174 Common Report Var(flag_cprop_registers) Optimization
1175 Perform a register copy-propagation optimization pass.
1177 fcrossjumping
1178 Common Report Var(flag_crossjumping) Optimization
1179 Perform cross-jumping optimization.
1181 fcse-follow-jumps
1182 Common Report Var(flag_cse_follow_jumps) Optimization
1183 When running CSE, follow jumps to their targets.
1185 fcse-skip-blocks
1186 Common Ignore
1187 Does nothing.  Preserved for backward compatibility.
1189 fcx-limited-range
1190 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
1191 Omit range reduction step when performing complex division.
1193 fcx-fortran-rules
1194 Common Report Var(flag_cx_fortran_rules) Optimization
1195 Complex multiplication and division follow Fortran rules.
1197 fdata-sections
1198 Common Report Var(flag_data_sections)
1199 Place data items into their own section.
1201 fdbg-cnt-list
1202 Common Report Var(common_deferred_options) Defer
1203 List all available debugging counters with their limits and counts.
1205 fdbg-cnt=
1206 Common RejectNegative Joined Var(common_deferred_options) Defer
1207 -fdbg-cnt=<counter>[:<lower_limit1>-]<upper_limit1>[:<lower_limit2>-<upper_limit2>:...][,<counter>:...] Set the debug counter limit.
1209 fdebug-prefix-map=
1210 Common Joined RejectNegative Var(common_deferred_options) Defer
1211 -fdebug-prefix-map=<old>=<new>  Map one directory name to another in debug information.
1213 ffile-prefix-map=
1214 Common Joined RejectNegative Var(common_deferred_options) Defer
1215 -ffile-prefix-map=<old>=<new>   Map one directory name to another in compilation result.
1217 fdebug-types-section
1218 Common Report Var(flag_debug_types_section) Init(0)
1219 Output .debug_types section when using DWARF v4 debuginfo.
1221 ; Nonzero for -fdefer-pop: don't pop args after each function call
1222 ; instead save them up to pop many calls' args with one insns.
1223 fdefer-pop
1224 Common Report Var(flag_defer_pop) Optimization
1225 Defer popping functions args from stack until later.
1227 fdelayed-branch
1228 Common Report Var(flag_delayed_branch) Optimization
1229 Attempt to fill delay slots of branch instructions.
1231 fdelete-dead-exceptions
1232 Common Report Var(flag_delete_dead_exceptions) Init(0) Optimization
1233 Delete dead instructions that may throw exceptions.
1235 fdelete-null-pointer-checks
1236 Common Report Var(flag_delete_null_pointer_checks) Init(-1) Optimization
1237 Delete useless null pointer checks.
1239 fdevirtualize-at-ltrans
1240 Common Report Var(flag_ltrans_devirtualize)
1241 Stream extra data to support more aggressive devirtualization in LTO local transformation mode.
1243 fdevirtualize-speculatively
1244 Common Report Var(flag_devirtualize_speculatively) Optimization
1245 Perform speculative devirtualization.
1247 fdevirtualize
1248 Common Report Var(flag_devirtualize) Optimization
1249 Try to convert virtual calls to direct ones.
1251 fdiagnostics-show-location=
1252 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1253 -fdiagnostics-show-location=[once|every-line]   How often to emit source location at the beginning of line-wrapped diagnostics.
1255 ; Required for these enum values.
1256 SourceInclude
1257 pretty-print.h
1259 Enum
1260 Name(diagnostic_prefixing_rule) Type(int)
1262 EnumValue
1263 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1265 EnumValue
1266 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1268 fdiagnostics-show-caret
1269 Common Var(flag_diagnostics_show_caret) Init(1)
1270 Show the source line with a caret indicating the column.
1272 fdiagnostics-show-labels
1273 Common Var(flag_diagnostics_show_labels) Init(1)
1274 Show labels annotating ranges of source code when showing source.
1276 fdiagnostics-show-line-numbers
1277 Common Var(flag_diagnostics_show_line_numbers) Init(1)
1278 Show line numbers in the left margin when showing source.
1280 fdiagnostics-color
1281 Common Alias(fdiagnostics-color=,always,never)
1284 fdiagnostics-color=
1285 Driver Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1286 -fdiagnostics-color=[never|always|auto] Colorize diagnostics.
1288 ; Required for these enum values.
1289 SourceInclude
1290 diagnostic-color.h
1292 Enum
1293 Name(diagnostic_color_rule) Type(int)
1295 EnumValue
1296 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1298 EnumValue
1299 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1301 EnumValue
1302 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1304 fdiagnostics-urls=
1305 Driver Common Joined RejectNegative Var(flag_diagnostics_show_urls) Enum(diagnostic_url_rule) Init(DIAGNOSTICS_URL_AUTO)
1306 -fdiagnostics-urls=[never|always|auto]  Embed URLs in diagnostics.
1308 ; Required for these enum values.
1309 SourceInclude
1310 diagnostic-url.h
1312 Enum
1313 Name(diagnostic_url_rule) Type(int)
1315 EnumValue
1316 Enum(diagnostic_url_rule) String(never) Value(DIAGNOSTICS_URL_NO)
1318 EnumValue
1319 Enum(diagnostic_url_rule) String(always) Value(DIAGNOSTICS_URL_YES)
1321 EnumValue
1322 Enum(diagnostic_url_rule) String(auto) Value(DIAGNOSTICS_URL_AUTO)
1324 fdiagnostics-format=
1325 Common Joined RejectNegative Enum(diagnostics_output_format)
1326 -fdiagnostics-format=[text|json]        Select output format.
1328 ; Required for these enum values.
1329 SourceInclude
1330 diagnostic.h
1332 Enum
1333 Name(diagnostics_output_format) Type(int)
1335 EnumValue
1336 Enum(diagnostics_output_format) String(text) Value(DIAGNOSTICS_OUTPUT_FORMAT_TEXT)
1338 EnumValue
1339 Enum(diagnostics_output_format) String(json) Value(DIAGNOSTICS_OUTPUT_FORMAT_JSON)
1341 fdiagnostics-parseable-fixits
1342 Common Var(flag_diagnostics_parseable_fixits)
1343 Print fix-it hints in machine-readable form.
1345 fdiagnostics-generate-patch
1346 Common Var(flag_diagnostics_generate_patch)
1347 Print fix-it hints to stderr in unified diff format.
1349 fdiagnostics-show-option
1350 Common Var(flag_diagnostics_show_option) Init(1)
1351 Amend appropriate diagnostic messages with the command line option that controls them.
1353 fdiagnostics-show-cwe
1354 Common Var(flag_diagnostics_show_cwe) Init(1)
1355 Print CWE identifiers for diagnostic messages, where available.
1357 fdiagnostics-path-format=
1358 Common Joined RejectNegative Var(flag_diagnostics_path_format) Enum(diagnostic_path_format) Init(DPF_INLINE_EVENTS)
1359 Specify how to print any control-flow path associated with a diagnostic.
1361 Enum
1362 Name(diagnostic_path_format) Type(int)
1364 EnumValue
1365 Enum(diagnostic_path_format) String(none) Value(DPF_NONE)
1367 EnumValue
1368 Enum(diagnostic_path_format) String(separate-events) Value(DPF_SEPARATE_EVENTS)
1370 EnumValue
1371 Enum(diagnostic_path_format) String(inline-events) Value(DPF_INLINE_EVENTS)
1373 fdiagnostics-show-path-depths
1374 Common Var(flag_diagnostics_show_path_depths) Init(0)
1375 Show stack depths of events in paths.
1377 fdiagnostics-minimum-margin-width=
1378 Common Joined UInteger Var(diagnostics_minimum_margin_width) Init(6)
1379 Set minimum width of left margin of source code when showing source.
1381 fdisable-
1382 Common Joined RejectNegative Var(common_deferred_options) Defer
1383 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2   Disable an optimization pass.
1385 fenable-
1386 Common Joined RejectNegative Var(common_deferred_options) Defer
1387 -fenable-[tree|rtl|ipa]-<pass>=range1+range2    Enable an optimization pass.
1389 fdump-
1390 Common Joined RejectNegative Var(common_deferred_options) Defer
1391 -fdump-<type>   Dump various compiler internals to a file.
1393 fdump-final-insns
1394 Driver RejectNegative
1396 fdump-final-insns=
1397 Common RejectNegative Joined Var(flag_dump_final_insns)
1398 -fdump-final-insns=filename     Dump to filename the insns at the end of translation.
1400 fdump-go-spec=
1401 Common RejectNegative Joined Var(flag_dump_go_spec)
1402 -fdump-go-spec=filename Write all declarations to file as Go code.
1404 fdump-noaddr
1405 Common Report Var(flag_dump_noaddr)
1406 Suppress output of addresses in debugging dumps.
1408 freport-bug
1409 Common Driver Var(flag_report_bug)
1410 Collect and dump debug information into temporary file if ICE in C/C++
1411 compiler occurred.
1413 fdump-internal-locations
1414 Common Var(flag_dump_locations) Init(0)
1415 Dump detailed information on GCC's internal representation of source code locations.
1417 fdump-passes
1418 Common Var(flag_dump_passes) Init(0)
1419 Dump optimization passes.
1421 fdump-unnumbered
1422 Common Report Var(flag_dump_unnumbered)
1423 Suppress output of instruction numbers, line number notes and addresses in debugging dumps.
1425 fdump-unnumbered-links
1426 Common Report Var(flag_dump_unnumbered_links)
1427 Suppress output of previous and next insn numbers in debugging dumps.
1429 fdwarf2-cfi-asm
1430 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1431 Enable CFI tables via GAS assembler directives.
1433 fearly-inlining
1434 Common Report Var(flag_early_inlining) Init(1) Optimization
1435 Perform early inlining.
1437 feliminate-dwarf2-dups
1438 Common Ignore
1439 Does nothing.  Preserved for backward compatibility.
1441 fipa-sra
1442 Common Report Var(flag_ipa_sra) Init(0) Optimization
1443 Perform interprocedural reduction of aggregates.
1445 feliminate-unused-debug-symbols
1446 Common Report Var(flag_debug_only_used_symbols) Init(1)
1447 Perform unused symbol elimination in debug info.
1449 feliminate-unused-debug-types
1450 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1451 Perform unused type elimination in debug info.
1453 femit-class-debug-always
1454 Common Report Var(flag_emit_class_debug_always) Init(0)
1455 Do not suppress C++ class debug information.
1457 fexceptions
1458 Common Report Var(flag_exceptions) Optimization
1459 Enable exception handling.
1461 fexpensive-optimizations
1462 Common Report Var(flag_expensive_optimizations) Optimization
1463 Perform a number of minor, expensive optimizations.
1465 fexcess-precision=
1466 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision) Init(EXCESS_PRECISION_DEFAULT) Optimization SetByCombined
1467 -fexcess-precision=[fast|standard]      Specify handling of excess floating-point precision.
1469 Enum
1470 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1472 EnumValue
1473 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1475 EnumValue
1476 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1478 ; Whether we permit the extended set of values for FLT_EVAL_METHOD
1479 ; introduced in ISO/IEC TS 18661-3, or limit ourselves to those in C99/C11.
1480 fpermitted-flt-eval-methods=
1481 Common Joined RejectNegative Enum(permitted_flt_eval_methods) Var(flag_permitted_flt_eval_methods) Init(PERMITTED_FLT_EVAL_METHODS_DEFAULT)
1482 -fpermitted-flt-eval-methods=[c11|ts-18661]     Specify which values of FLT_EVAL_METHOD are permitted.
1484 Enum
1485 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)
1487 EnumValue
1488 Enum(permitted_flt_eval_methods) String(c11) Value(PERMITTED_FLT_EVAL_METHODS_C11)
1490 EnumValue
1491 Enum(permitted_flt_eval_methods) String(ts-18661-3) Value(PERMITTED_FLT_EVAL_METHODS_TS_18661)
1493 ffast-math
1494 Common Optimization
1496 ffat-lto-objects
1497 Common Var(flag_fat_lto_objects)
1498 Output lto objects containing both the intermediate language and binary output.
1500 ffinite-math-only
1501 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1502 Assume no NaNs or infinities are generated.
1504 ffinite-loops
1505 Common Report Var(flag_finite_loops) Optimization Init(0)
1506 Assume that loops with an exit will terminate and not loop indefinitely.
1508 ffixed-
1509 Common Joined RejectNegative Var(common_deferred_options) Defer
1510 -ffixed-<register>      Mark <register> as being unavailable to the compiler.
1512 ffloat-store
1513 Common Report Var(flag_float_store) Optimization
1514 Don't allocate floats and doubles in extended-precision registers.
1516 fforce-addr
1517 Common Ignore
1518 Does nothing.  Preserved for backward compatibility.
1520 fforward-propagate
1521 Common Report Var(flag_forward_propagate) Optimization
1522 Perform a forward propagation pass on RTL.
1524 ffp-contract=
1525 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST) Optimization
1526 -ffp-contract=[off|on|fast]     Perform floating-point expression contraction.
1528 Enum
1529 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1531 EnumValue
1532 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1534 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1535 EnumValue
1536 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1538 EnumValue
1539 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1541 ffp-int-builtin-inexact
1542 Common Report Var(flag_fp_int_builtin_inexact) Init(1) Optimization
1543 Allow built-in functions ceil, floor, round, trunc to raise \"inexact\" exceptions.
1545 ; Nonzero means don't put addresses of constant functions in registers.
1546 ; Used for compiling the Unix kernel, where strange substitutions are
1547 ; done on the assembly output.
1548 ffunction-cse
1549 Common Report Var(flag_no_function_cse,0) Optimization
1550 Allow function addresses to be held in registers.
1552 ffunction-sections
1553 Common Report Var(flag_function_sections)
1554 Place each function into its own section.
1556 fgcse
1557 Common Report Var(flag_gcse) Optimization
1558 Perform global common subexpression elimination.
1560 fgcse-lm
1561 Common Report Var(flag_gcse_lm) Init(1) Optimization
1562 Perform enhanced load motion during global common subexpression elimination.
1564 fgcse-sm
1565 Common Report Var(flag_gcse_sm) Init(0) Optimization
1566 Perform store motion after global common subexpression elimination.
1568 fgcse-las
1569 Common Report Var(flag_gcse_las) Init(0) Optimization
1570 Perform redundant load after store elimination in global common subexpression
1571 elimination.
1573 fgcse-after-reload
1574 Common Report Var(flag_gcse_after_reload) Optimization
1575 Perform global common subexpression elimination after register allocation has
1576 finished.
1578 Enum
1579 Name(dwarf_gnat_encodings) Type(int)
1581 EnumValue
1582 Enum(dwarf_gnat_encodings) String(all) Value(DWARF_GNAT_ENCODINGS_ALL)
1584 EnumValue
1585 Enum(dwarf_gnat_encodings) String(gdb) Value(DWARF_GNAT_ENCODINGS_GDB)
1587 EnumValue
1588 Enum(dwarf_gnat_encodings) String(minimal) Value(DWARF_GNAT_ENCODINGS_MINIMAL)
1590 fgnat-encodings=
1591 Common Enum(dwarf_gnat_encodings) Joined RejectNegative Report Undocumented Var(gnat_encodings)
1592 -fgnat-encodings=[all|gdb|minimal]      Select the balance between GNAT encodings and standard DWARF emitted in the debug information.
1594 ; This option is not documented yet as its semantics will change.
1595 fgraphite
1596 Common Report Var(flag_graphite) Optimization
1597 Enable in and out of Graphite representation.
1599 fgraphite-identity
1600 Common Report Var(flag_graphite_identity) Optimization
1601 Enable Graphite Identity transformation.
1603 fhoist-adjacent-loads
1604 Common Report Var(flag_hoist_adjacent_loads) Optimization
1605 Enable hoisting adjacent loads to encourage generating conditional move
1606 instructions.
1608 fkeep-gc-roots-live
1609 Common Undocumented Report Var(flag_keep_gc_roots_live) Optimization
1610 ; Always keep a pointer to a live memory block
1612 floop-parallelize-all
1613 Common Report Var(flag_loop_parallelize_all) Optimization
1614 Mark all loops as parallel.
1616 floop-strip-mine
1617 Common Alias(floop-nest-optimize)
1618 Enable loop nest transforms.  Same as -floop-nest-optimize.
1620 floop-interchange
1621 Common Report Var(flag_loop_interchange) Optimization
1622 Enable loop interchange on trees.
1624 floop-block
1625 Common Alias(floop-nest-optimize)
1626 Enable loop nest transforms.  Same as -floop-nest-optimize.
1628 floop-unroll-and-jam
1629 Common Report Var(flag_unroll_jam) Optimization
1630 Perform unroll-and-jam on loops.
1632 fgnu-tm
1633 Common Report Var(flag_tm)
1634 Enable support for GNU transactional memory.
1636 fgnu-unique
1637 Common Report Var(flag_gnu_unique) Init(1)
1638 Use STB_GNU_UNIQUE if supported by the assembler.
1640 floop-flatten
1641 Common Ignore
1642 Does nothing. Preserved for backward compatibility.
1644 floop-nest-optimize
1645 Common Report Var(flag_loop_nest_optimize) Optimization
1646 Enable the loop nest optimizer.
1648 fstrict-volatile-bitfields
1649 Common Report Var(flag_strict_volatile_bitfields) Init(-1) Optimization
1650 Force bitfield accesses to match their type width.
1652 fstore-merging
1653 Common Report Var(flag_store_merging) Optimization
1654 Merge adjacent stores.
1656 fguess-branch-probability
1657 Common Report Var(flag_guess_branch_prob) Optimization
1658 Enable guessing of branch probabilities.
1660 ; Nonzero means ignore `#ident' directives.  0 means handle them.
1661 ; Generate position-independent code for executables if possible
1662 ; On SVR4 targets, it also controls whether or not to emit a
1663 ; string identifying the compiler.
1664 fident
1665 Common Report Var(flag_no_ident,0)
1666 Process #ident directives.
1668 fif-conversion
1669 Common Report Var(flag_if_conversion) Optimization
1670 Perform conversion of conditional jumps to branchless equivalents.
1672 fif-conversion2
1673 Common Report Var(flag_if_conversion2) Optimization
1674 Perform conversion of conditional jumps to conditional execution.
1676 fstack-reuse=
1677 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL) Optimization
1678 -fstack-reuse=[all|named_vars|none]     Set stack reuse level for local variables.
1680 Enum
1681 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1683 EnumValue
1684 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1686 EnumValue
1687 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1689 EnumValue
1690 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1692 ftree-loop-if-convert
1693 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1694 Convert conditional jumps in innermost loops to branchless equivalents.
1696 ftree-loop-if-convert-stores
1697 Common Ignore
1698 Does nothing. Preserved for backward compatibility.
1700 ; -finhibit-size-directive inhibits output of .size for ELF.
1701 ; This is used only for compiling crtstuff.c,
1702 ; and it may be extended to other effects
1703 ; needed for crtstuff.c on other systems.
1704 finhibit-size-directive
1705 Common Report Var(flag_inhibit_size_directive)
1706 Do not generate .size directives.
1708 findirect-inlining
1709 Common Report Var(flag_indirect_inlining) Optimization
1710 Perform indirect inlining.
1712 ; General flag to enable inlining.  Specifying -fno-inline will disable
1713 ; all inlining apart from always-inline functions.
1714 finline
1715 Common Report Var(flag_no_inline,0) Init(0) Optimization
1716 Enable inlining of function declared \"inline\", disabling disables all inlining.
1718 finline-small-functions
1719 Common Report Var(flag_inline_small_functions) Optimization
1720 Integrate functions into their callers when code size is known not to grow.
1722 finline-functions
1723 Common Report Var(flag_inline_functions) Optimization
1724 Integrate functions not declared \"inline\" into their callers when profitable.
1726 finline-functions-called-once
1727 Common Report Var(flag_inline_functions_called_once) Optimization
1728 Integrate functions only required by their single caller.
1730 finline-limit-
1731 Common RejectNegative Joined Alias(finline-limit=)
1733 finline-limit=
1734 Common RejectNegative Joined UInteger
1735 -finline-limit=<number> Limit the size of inlined functions to <number>.
1737 finline-atomics
1738 Common Report Var(flag_inline_atomics) Init(1) Optimization
1739 Inline __atomic operations when a lock free instruction sequence is available.
1741 fcf-protection
1742 Common RejectNegative Alias(fcf-protection=,full)
1744 fcf-protection=
1745 Common Report Joined RejectNegative Enum(cf_protection_level) Var(flag_cf_protection) Init(CF_NONE)
1746 -fcf-protection=[full|branch|return|none]       Instrument functions with checks to verify jump/call/return control-flow transfer
1747 instructions have valid targets.
1749 Enum
1750 Name(cf_protection_level) Type(enum cf_protection_level) UnknownError(unknown Control-Flow Protection Level %qs)
1752 EnumValue
1753 Enum(cf_protection_level) String(full) Value(CF_FULL)
1755 EnumValue
1756 Enum(cf_protection_level) String(branch) Value(CF_BRANCH)
1758 EnumValue
1759 Enum(cf_protection_level) String(return) Value(CF_RETURN)
1761 EnumValue
1762 Enum(cf_protection_level) String(none) Value(CF_NONE)
1764 finstrument-functions
1765 Common Report Var(flag_instrument_function_entry_exit)
1766 Instrument function entry and exit with profiling calls.
1768 finstrument-functions-exclude-function-list=
1769 Common RejectNegative Joined
1770 -finstrument-functions-exclude-function-list=name,...   Do not instrument listed functions.
1772 finstrument-functions-exclude-file-list=
1773 Common RejectNegative Joined
1774 -finstrument-functions-exclude-file-list=filename,...   Do not instrument functions listed in files.
1776 fipa-cp
1777 Common Report Var(flag_ipa_cp) Optimization
1778 Perform interprocedural constant propagation.
1780 fipa-cp-clone
1781 Common Report Var(flag_ipa_cp_clone) Optimization
1782 Perform cloning to make Interprocedural constant propagation stronger.
1784 fipa-cp-alignment
1785 Common Ignore
1786 Does nothing.  Preserved for backward compatibility.
1788 fipa-bit-cp
1789 Common Report Var(flag_ipa_bit_cp) Optimization
1790 Perform interprocedural bitwise constant propagation.
1792 fipa-profile
1793 Common Report Var(flag_ipa_profile) Init(0) Optimization
1794 Perform interprocedural profile propagation.
1796 fipa-pta
1797 Common Report Var(flag_ipa_pta) Init(0) Optimization
1798 Perform interprocedural points-to analysis.
1800 fipa-pure-const
1801 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1802 Discover pure and const functions.
1804 fipa-icf
1805 Common Report Var(flag_ipa_icf) Optimization
1806 Perform Identical Code Folding for functions and read-only variables.
1808 fipa-icf-functions
1809 Common Report Var(flag_ipa_icf_functions) Optimization
1810 Perform Identical Code Folding for functions.
1812 fipa-icf-variables
1813 Common Report Var(flag_ipa_icf_variables) Optimization
1814 Perform Identical Code Folding for variables.
1816 fipa-reference
1817 Common Report Var(flag_ipa_reference) Init(0) Optimization
1818 Discover read-only and non addressable static variables.
1820 fipa-reference-addressable
1821 Common Report Var(flag_ipa_reference_addressable) Init(0) Optimization
1822 Discover read-only, write-only and non-addressable static variables.
1824 fipa-stack-alignment
1825 Common Report Var(flag_ipa_stack_alignment) Init(1) Optimization
1826 Reduce stack alignment on call sites if possible.
1828 fipa-matrix-reorg
1829 Common Ignore
1830 Does nothing. Preserved for backward compatibility.
1832 fipa-struct-reorg
1833 Common Ignore
1834 Does nothing. Preserved for backward compatibility.
1836 fipa-vrp
1837 Common Report Var(flag_ipa_vrp) Optimization
1838 Perform IPA Value Range Propagation.
1840 fira-algorithm=
1841 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB) Optimization
1842 -fira-algorithm=[CB|priority]   Set the used IRA algorithm.
1844 Enum
1845 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1847 EnumValue
1848 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1850 EnumValue
1851 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1853 fira-region=
1854 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT) Optimization
1855 -fira-region=[one|all|mixed]    Set regions for IRA.
1857 Enum
1858 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1860 EnumValue
1861 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1863 EnumValue
1864 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1866 EnumValue
1867 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1869 fira-hoist-pressure
1870 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1871 Use IRA based register pressure calculation
1872 in RTL hoist optimizations.
1874 fira-loop-pressure
1875 Common Report Var(flag_ira_loop_pressure) Optimization
1876 Use IRA based register pressure calculation
1877 in RTL loop optimizations.
1879 fira-share-save-slots
1880 Common Report Var(flag_ira_share_save_slots) Init(1) Optimization
1881 Share slots for saving different hard registers.
1883 fira-share-spill-slots
1884 Common Report Var(flag_ira_share_spill_slots) Init(1) Optimization
1885 Share stack slots for spilled pseudo-registers.
1887 fira-verbose=
1888 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1889 -fira-verbose=<number>  Control IRA's level of diagnostic messages.
1891 fivopts
1892 Common Report Var(flag_ivopts) Init(1) Optimization
1893 Optimize induction variables on trees.
1895 fjump-tables
1896 Common Var(flag_jump_tables) Init(1) Optimization
1897 Use jump tables for sufficiently large switch statements.
1899 fkeep-inline-functions
1900 Common Report Var(flag_keep_inline_functions)
1901 Generate code for functions even if they are fully inlined.
1903 fkeep-static-functions
1904 Common Report Var(flag_keep_static_functions)
1905 Generate code for static functions even if they are never called.
1907 fkeep-static-consts
1908 Common Report Var(flag_keep_static_consts) Init(1)
1909 Emit static const variables even if they are not used.
1911 fleading-underscore
1912 Common Report Var(flag_leading_underscore) Init(-1)
1913 Give external symbols a leading underscore.
1915 floop-optimize
1916 Common Ignore
1917 Does nothing.  Preserved for backward compatibility.
1919 flra-remat
1920 Common Report Var(flag_lra_remat) Optimization
1921 Do CFG-sensitive rematerialization in LRA.
1923 flto
1924 Common
1925 Enable link-time optimization.
1927 flto=
1928 Common RejectNegative Joined Var(flag_lto)
1929 Link-time optimization with number of parallel jobs or jobserver.
1931 Enum
1932 Name(lto_partition_model) Type(enum lto_partition_model) UnknownError(unknown LTO partitioning model %qs)
1934 EnumValue
1935 Enum(lto_partition_model) String(none) Value(LTO_PARTITION_NONE)
1937 EnumValue
1938 Enum(lto_partition_model) String(one) Value(LTO_PARTITION_ONE)
1940 EnumValue
1941 Enum(lto_partition_model) String(balanced) Value(LTO_PARTITION_BALANCED)
1943 EnumValue
1944 Enum(lto_partition_model) String(1to1) Value(LTO_PARTITION_1TO1)
1946 EnumValue
1947 Enum(lto_partition_model) String(max) Value(LTO_PARTITION_MAX)
1949 flto-partition=
1950 Common Joined RejectNegative Enum(lto_partition_model) Var(flag_lto_partition) Init(LTO_PARTITION_BALANCED)
1951 Specify the algorithm to partition symbols and vars at linktime.
1953 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1954 flto-compression-level=
1955 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1) IntegerRange(0, 19)
1956 -flto-compression-level=<number>        Use zlib/zstd compression level <number> for IL.
1958 flto-odr-type-merging
1959 Common Ignore
1960 Does nothing.  Preserved for backward compatibility.
1962 flto-report
1963 Common Report Var(flag_lto_report) Init(0)
1964 Report various link-time optimization statistics.
1966 flto-report-wpa
1967 Common Report Var(flag_lto_report_wpa) Init(0)
1968 Report various link-time optimization statistics for WPA only.
1970 fmath-errno
1971 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1972 Set errno after built-in math functions.
1974 fmax-errors=
1975 Common Joined RejectNegative UInteger Var(flag_max_errors)
1976 -fmax-errors=<number>   Maximum number of errors to report.
1978 fmem-report
1979 Common Report Var(mem_report)
1980 Report on permanent memory allocation.
1982 fmem-report-wpa
1983 Common Report Var(mem_report_wpa)
1984 Report on permanent memory allocation in WPA only.
1986 ; This will attempt to merge constant section constants, if 1 only
1987 ; string constants and constants from constant pool, if 2 also constant
1988 ; variables.
1989 fmerge-all-constants
1990 Common Report Var(flag_merge_constants,2) Init(1)
1991 Attempt to merge identical constants and constant variables.
1993 fmerge-constants
1994 Common Report Var(flag_merge_constants,1)
1995 Attempt to merge identical constants across compilation units.
1997 fmerge-debug-strings
1998 Common Report Var(flag_merge_debug_strings) Init(1)
1999 Attempt to merge identical debug strings across compilation units.
2001 fmessage-length=
2002 Common RejectNegative Joined UInteger
2003 -fmessage-length=<number>       Limit diagnostics to <number> characters per line.  0 suppresses line-wrapping.
2005 fmodulo-sched
2006 Common Report Var(flag_modulo_sched) Optimization
2007 Perform SMS based modulo scheduling before the first scheduling pass.
2009 fmodulo-sched-allow-regmoves
2010 Common Report Var(flag_modulo_sched_allow_regmoves) Optimization
2011 Perform SMS based modulo scheduling with register moves allowed.
2013 fmove-loop-invariants
2014 Common Report Var(flag_move_loop_invariants) Optimization
2015 Move loop invariant computations out of loops.
2017 fdce
2018 Common Var(flag_dce) Init(1) Optimization
2019 Use the RTL dead code elimination pass.
2021 fdse
2022 Common Var(flag_dse) Init(0) Optimization
2023 Use the RTL dead store elimination pass.
2025 freschedule-modulo-scheduled-loops
2026 Common Report Var(flag_resched_modulo_sched) Optimization
2027 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling.
2029 fnon-call-exceptions
2030 Common Report Var(flag_non_call_exceptions) Optimization
2031 Support synchronous non-call exceptions.
2033 foffload=
2034 Common Driver Joined MissingArgError(options or targets missing after %qs)
2035 -foffload=<targets>=<options>   Specify offloading targets and options for them.
2037 foffload-abi=
2038 Common Joined RejectNegative Enum(offload_abi) Var(flag_offload_abi) Init(OFFLOAD_ABI_UNSET)
2039 -foffload-abi=[lp64|ilp32]      Set the ABI to use in an offload compiler.
2041 Enum
2042 Name(offload_abi) Type(enum offload_abi) UnknownError(unknown offload ABI %qs)
2044 EnumValue
2045 Enum(offload_abi) String(ilp32) Value(OFFLOAD_ABI_ILP32)
2047 EnumValue
2048 Enum(offload_abi) String(lp64) Value(OFFLOAD_ABI_LP64)
2050 fomit-frame-pointer
2051 Common Report Var(flag_omit_frame_pointer) Optimization
2052 When possible do not generate stack frames.
2054 fopt-info
2055 Common Report Var(flag_opt_info) Optimization
2056 Enable all optimization info dumps on stderr.
2058 fopt-info-
2059 Common Joined RejectNegative Var(common_deferred_options) Defer
2060 -fopt-info[-<type>=filename]    Dump compiler optimization details.
2062 fsave-optimization-record
2063 Common Report Var(flag_save_optimization_record) Optimization
2064 Write a SRCFILE.opt-record.json file detailing what optimizations were performed.
2066 foptimize-register-move
2067 Common Ignore
2068 Does nothing. Preserved for backward compatibility.
2070 foptimize-sibling-calls
2071 Common Report Var(flag_optimize_sibling_calls) Optimization
2072 Optimize sibling and tail recursive calls.
2074 fpartial-inlining
2075 Common Report Var(flag_partial_inlining) Optimization
2076 Perform partial inlining.
2078 fpre-ipa-mem-report
2079 Common Report Var(pre_ipa_mem_report)
2080 Report on memory allocation before interprocedural optimization.
2082 fpost-ipa-mem-report
2083 Common Report Var(post_ipa_mem_report)
2084 Report on memory allocation before interprocedural optimization.
2086 fpack-struct
2087 Common Report Var(flag_pack_struct) Optimization
2088 Pack structure members together without holes.
2090 fpack-struct=
2091 Common RejectNegative Joined UInteger Optimization
2092 -fpack-struct=<number>  Set initial maximum structure member alignment.
2094 fpcc-struct-return
2095 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
2096 Return small aggregates in memory, not registers.
2098 fpeel-loops
2099 Common Report Var(flag_peel_loops) Optimization
2100 Perform loop peeling.
2102 fpeephole
2103 Common Report Var(flag_no_peephole,0) Optimization
2104 Enable machine specific peephole optimizations.
2106 fpeephole2
2107 Common Report Var(flag_peephole2) Optimization
2108 Enable an RTL peephole pass before sched2.
2110 fPIC
2111 Common Report Var(flag_pic,2) Negative(fPIE) Init(-1)
2112 Generate position-independent code if possible (large mode).
2114 fPIE
2115 Common Report Var(flag_pie,2) Negative(fpic) Init(-1)
2116 Generate position-independent code for executables if possible (large mode).
2118 fpic
2119 Common Report Var(flag_pic,1) Negative(fpie) Init(-1)
2120 Generate position-independent code if possible (small mode).
2122 fpie
2123 Common Report Var(flag_pie,1) Negative(fPIC) Init(-1)
2124 Generate position-independent code for executables if possible (small mode).
2126 fplt
2127 Common Report Var(flag_plt) Init(1) Optimization
2128 Use PLT for PIC calls (-fno-plt: load the address from GOT at call site).
2130 fplugin=
2131 Common Joined RejectNegative Var(common_deferred_options) Defer
2132 Specify a plugin to load.
2134 fplugin-arg-
2135 Common Joined RejectNegative Var(common_deferred_options) Defer
2136 -fplugin-arg-<name>-<key>[=<value>]     Specify argument <key>=<value> for plugin <name>.
2138 fpredictive-commoning
2139 Common Report Var(flag_predictive_commoning) Optimization
2140 Run predictive commoning optimization.
2142 fprefetch-loop-arrays
2143 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
2144 Generate prefetch instructions, if available, for arrays in loops.
2146 fprofile
2147 Common Report Var(profile_flag)
2148 Enable basic program profiling code.
2150 fprofile-abs-path
2151 Common Report Var(profile_abs_path_flag)
2152 Generate absolute source path names for gcov.
2154 fprofile-arcs
2155 Common Report Var(profile_arc_flag)
2156 Insert arc-based program profiling code.
2158 fprofile-dir=
2159 Common Joined RejectNegative Var(profile_data_prefix)
2160 Set the top-level directory for storing the profile data.
2161 The default is 'pwd'.
2163 fprofile-note=
2164 Common Joined RejectNegative Var(profile_note_location)
2165 Select the name for storing the profile note file.
2167 fprofile-correction
2168 Common Report Var(flag_profile_correction)
2169 Enable correction of flow inconsistent profile data input.
2171 fprofile-update=
2172 Common Joined RejectNegative Enum(profile_update) Var(flag_profile_update) Init(PROFILE_UPDATE_SINGLE)
2173 -fprofile-update=[single|atomic|prefer-atomic]  Set the profile update method.
2175 fprofile-filter-files=
2176 Common Joined RejectNegative Var(flag_profile_filter_files)
2177 Instrument only functions from files where names match any regular expression (separated by a semi-colon).
2179 fprofile-exclude-files=
2180 Common Joined RejectNegative Var(flag_profile_exclude_files)
2181 Instrument only functions from files where names do not match all the regular expressions (separated by a semi-colon).
2183 Enum
2184 Name(profile_reproducibility) Type(enum profile_reproducibility) UnknownError(unknown profile reproducibility method %qs)
2186 EnumValue
2187 Enum(profile_reproducibility) String(serial) Value(PROFILE_REPRODUCIBILITY_SERIAL)
2189 EnumValue
2190 Enum(profile_reproducibility) String(parallel-runs) Value(PROFILE_REPRODUCIBILITY_PARALLEL_RUNS)
2192 EnumValue
2193 Enum(profile_reproducibility) String(multithreaded) Value(PROFILE_REPRODUCIBILITY_MULTITHREADED)
2195 fprofile-reproducible
2196 Common Joined RejectNegative Var(flag_profile_reproducible) Enum(profile_reproducibility) Init(PROFILE_REPRODUCIBILITY_SERIAL)
2197 -fprofile-reproducible=[serial|parallel-runs|multithreaded]     Control level of reproducibility of profile gathered by -fprofile-generate.
2199 Enum
2200 Name(profile_update) Type(enum profile_update) UnknownError(unknown profile update method %qs)
2202 EnumValue
2203 Enum(profile_update) String(single) Value(PROFILE_UPDATE_SINGLE)
2205 EnumValue
2206 Enum(profile_update) String(atomic) Value(PROFILE_UPDATE_ATOMIC)
2208 EnumValue
2209 Enum(profile_update) String(prefer-atomic) Value(PROFILE_UPDATE_PREFER_ATOMIC)
2211 fprofile-prefix-path=
2212 Common Joined RejectNegative Var(profile_prefix_path)
2213 Remove prefix from absolute path before manging name for -fprofile-generate= and -fprofile-use=.
2215 fprofile-generate
2216 Common
2217 Enable common options for generating profile info for profile feedback directed optimizations.
2219 fprofile-generate=
2220 Common Joined RejectNegative
2221 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=.
2223 fprofile-partial-training
2224 Common Report Var(flag_profile_partial_training) Optimization
2225 Do not assume that functions never executed during the train run are cold.
2227 fprofile-use
2228 Common Var(flag_profile_use)
2229 Enable common options for performing profile feedback directed optimizations.
2231 fprofile-use=
2232 Common Joined RejectNegative
2233 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=.
2235 fprofile-values
2236 Common Report Var(flag_profile_values)
2237 Insert code to profile values of expressions.
2239 fprofile-report
2240 Common Report Var(profile_report)
2241 Report on consistency of profile.
2243 fprofile-reorder-functions
2244 Common Report Var(flag_profile_reorder_functions) Optimization
2245 Enable function reordering that improves code placement.
2247 fpatchable-function-entry=
2248 Common Joined Optimization
2249 Insert NOP instructions at each function entry.
2251 frandom-seed
2252 Common Var(common_deferred_options) Defer
2254 frandom-seed=
2255 Common Joined RejectNegative Var(common_deferred_options) Defer
2256 -frandom-seed=<string>  Make compile reproducible using <string>.
2258 ; This switch causes the command line that was used to create an
2259 ; object file to be recorded into the object file.  The exact format
2260 ; of this recording is target and binary file format dependent.
2261 ; It is related to the -fverbose-asm switch, but that switch only
2262 ; records information in the assembler output file as comments, so
2263 ; they never reach the object file.
2264 frecord-gcc-switches
2265 Common Report Var(flag_record_gcc_switches)
2266 Record gcc command line switches in the object file.
2268 freg-struct-return
2269 Common Report Var(flag_pcc_struct_return,0) Optimization
2270 Return small aggregates in registers.
2272 fregmove
2273 Common Ignore
2274 Does nothing. Preserved for backward compatibility.
2276 flifetime-dse
2277 Common Report Var(flag_lifetime_dse,2) Init(2) Optimization
2278 Tell DSE that the storage for a C++ object is dead when the constructor
2279 starts and when the destructor finishes.
2281 flifetime-dse=
2282 Common Joined RejectNegative UInteger Var(flag_lifetime_dse) Optimization IntegerRange(0, 2)
2284 flive-patching
2285 Common RejectNegative Alias(flive-patching=,inline-clone) Optimization
2287 flive-patching=
2288 Common Report Joined RejectNegative Enum(live_patching_level) Var(flag_live_patching) Init(LIVE_PATCHING_NONE) Optimization
2289 -flive-patching=[inline-only-static|inline-clone]       Control IPA
2290 optimizations to provide a safe compilation for live-patching.  At the same
2291 time, provides multiple-level control on the enabled IPA optimizations.
2293 Enum
2294 Name(live_patching_level) Type(enum live_patching_level) UnknownError(unknown Live-Patching Level %qs)
2296 EnumValue
2297 Enum(live_patching_level) String(inline-only-static) Value(LIVE_PATCHING_INLINE_ONLY_STATIC)
2299 EnumValue
2300 Enum(live_patching_level) String(inline-clone) Value(LIVE_PATCHING_INLINE_CLONE)
2302 fallocation-dce
2303 Common Report Var(flag_allocation_dce) Init(1) Optimization
2304 Tell DCE to remove unused C++ allocations.
2306 flive-range-shrinkage
2307 Common Report Var(flag_live_range_shrinkage) Init(0) Optimization
2308 Relief of register pressure through live range shrinkage.
2310 frename-registers
2311 Common Report Var(flag_rename_registers) Init(2) Optimization
2312 Perform a register renaming optimization pass.
2314 fschedule-fusion
2315 Common Report Var(flag_schedule_fusion) Init(2) Optimization
2316 Perform a target dependent instruction fusion optimization pass.
2318 freorder-blocks
2319 Common Report Var(flag_reorder_blocks) Optimization
2320 Reorder basic blocks to improve code placement.
2322 freorder-blocks-algorithm=
2323 Common Joined RejectNegative Enum(reorder_blocks_algorithm) Var(flag_reorder_blocks_algorithm) Init(REORDER_BLOCKS_ALGORITHM_SIMPLE) Optimization
2324 -freorder-blocks-algorithm=[simple|stc] Set the used basic block reordering algorithm.
2326 Enum
2327 Name(reorder_blocks_algorithm) Type(enum reorder_blocks_algorithm) UnknownError(unknown basic block reordering algorithm %qs)
2329 EnumValue
2330 Enum(reorder_blocks_algorithm) String(simple) Value(REORDER_BLOCKS_ALGORITHM_SIMPLE)
2332 EnumValue
2333 Enum(reorder_blocks_algorithm) String(stc) Value(REORDER_BLOCKS_ALGORITHM_STC)
2335 freorder-blocks-and-partition
2336 Common Report Var(flag_reorder_blocks_and_partition) Optimization
2337 Reorder basic blocks and partition into hot and cold sections.
2339 freorder-functions
2340 Common Report Var(flag_reorder_functions) Optimization
2341 Reorder functions to improve code placement.
2343 frerun-cse-after-loop
2344 Common Report Var(flag_rerun_cse_after_loop) Optimization
2345 Add a common subexpression elimination pass after loop optimizations.
2347 frerun-loop-opt
2348 Common Ignore
2349 Does nothing.  Preserved for backward compatibility.
2351 frounding-math
2352 Common Report Var(flag_rounding_math) Optimization SetByCombined
2353 Disable optimizations that assume default FP rounding behavior.
2355 fsched-interblock
2356 Common Report Var(flag_schedule_interblock) Init(1) Optimization
2357 Enable scheduling across basic blocks.
2359 fsched-pressure
2360 Common Report Var(flag_sched_pressure) Init(0) Optimization
2361 Enable register pressure sensitive insn scheduling.
2363 fsched-spec
2364 Common Report Var(flag_schedule_speculative) Init(1) Optimization
2365 Allow speculative motion of non-loads.
2367 fsched-spec-load
2368 Common Report Var(flag_schedule_speculative_load) Optimization
2369 Allow speculative motion of some loads.
2371 fsched-spec-load-dangerous
2372 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
2373 Allow speculative motion of more loads.
2375 fsched-verbose=
2376 Common RejectNegative Joined UInteger Var(sched_verbose_param) Init(1)
2377 -fsched-verbose=<number>        Set the verbosity level of the scheduler.
2379 fsched2-use-superblocks
2380 Common Report Var(flag_sched2_use_superblocks) Optimization
2381 If scheduling post reload, do superblock scheduling.
2383 fsched2-use-traces
2384 Common Ignore
2385 Does nothing.  Preserved for backward compatibility.
2387 fschedule-insns
2388 Common Report Var(flag_schedule_insns) Optimization
2389 Reschedule instructions before register allocation.
2391 fschedule-insns2
2392 Common Report Var(flag_schedule_insns_after_reload) Optimization
2393 Reschedule instructions after register allocation.
2395 ; This flag should be on when a target implements non-trivial
2396 ; scheduling hooks, maybe saving some information for its own sake.
2397 ; On IA64, for example, this is used for correct bundling.
2398 fselective-scheduling
2399 Common Report Var(flag_selective_scheduling) Optimization
2400 Schedule instructions using selective scheduling algorithm.
2402 fselective-scheduling2
2403 Common Report Var(flag_selective_scheduling2) Optimization
2404 Run selective scheduling after reload.
2406 fself-test=
2407 Common Undocumented Joined Var(flag_self_test)
2408 Run self-tests, using the given path to locate test files.
2410 fsel-sched-pipelining
2411 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
2412 Perform software pipelining of inner loops during selective scheduling.
2414 fsel-sched-pipelining-outer-loops
2415 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
2416 Perform software pipelining of outer loops during selective scheduling.
2418 fsel-sched-reschedule-pipelined
2419 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
2420 Reschedule pipelined regions without pipelining.
2422 fsemantic-interposition
2423 Common Report Var(flag_semantic_interposition) Init(1)
2424 Allow interposing function (or variables) by ones with different semantics (or initializer) respectively by dynamic linker.
2426 ; sched_stalled_insns means that insns can be moved prematurely from the queue
2427 ; of stalled insns into the ready list.
2428 fsched-stalled-insns
2429 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
2430 Allow premature scheduling of queued insns.
2432 fsched-stalled-insns=
2433 Common RejectNegative Joined UInteger Optimization
2434 -fsched-stalled-insns=<number>  Set number of queued insns that can be prematurely scheduled.
2436 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
2437 ; be examined for a dependency on a stalled insn that is candidate for
2438 ; premature removal from the queue of stalled insns into the ready list (has
2439 ; an effect only if the flag 'sched_stalled_insns' is set).
2440 fsched-stalled-insns-dep
2441 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
2442 Set dependence distance checking in premature scheduling of queued insns.
2444 fsched-stalled-insns-dep=
2445 Common RejectNegative Joined UInteger Optimization
2446 -fsched-stalled-insns-dep=<number>      Set dependence distance checking in premature scheduling of queued insns.
2448 fsched-group-heuristic
2449 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
2450 Enable the group heuristic in the scheduler.
2452 fsched-critical-path-heuristic
2453 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
2454 Enable the critical path heuristic in the scheduler.
2456 fsched-spec-insn-heuristic
2457 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
2458 Enable the speculative instruction heuristic in the scheduler.
2460 fsched-rank-heuristic
2461 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
2462 Enable the rank heuristic in the scheduler.
2464 fsched-last-insn-heuristic
2465 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
2466 Enable the last instruction heuristic in the scheduler.
2468 fsched-dep-count-heuristic
2469 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
2470 Enable the dependent count heuristic in the scheduler.
2472 fsection-anchors
2473 Common Report Var(flag_section_anchors) Optimization
2474 Access data in the same section from shared anchor points.
2476 fsee
2477 Common Ignore
2478 Does nothing.  Preserved for backward compatibility.
2480 fzee
2481 Common Ignore
2482 Does nothing.  Preserved for backward compatibility.
2484 free
2485 Common Report Var(flag_ree) Init(0) Optimization
2486 Turn on Redundant Extensions Elimination pass.
2488 fshow-column
2489 Common Report Var(flag_show_column) Init(1)
2490 Show column numbers in diagnostics, when available.  Default on.
2492 fshrink-wrap
2493 Common Report Var(flag_shrink_wrap) Optimization
2494 Emit function prologues only before parts of the function that need it,
2495 rather than at the top of the function.
2497 fshrink-wrap-separate
2498 Common Report Var(flag_shrink_wrap_separate) Init(1) Optimization
2499 Shrink-wrap parts of the prologue and epilogue separately.
2501 fsignaling-nans
2502 Common Report Var(flag_signaling_nans) Optimization SetByCombined
2503 Disable optimizations observable by IEEE signaling NaNs.
2505 fsigned-zeros
2506 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
2507 Disable floating point optimizations that ignore the IEEE signedness of zero.
2509 fsingle-precision-constant
2510 Common Report Var(flag_single_precision_constant) Optimization
2511 Convert floating point constants to single precision constants.
2513 fsplit-ivs-in-unroller
2514 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
2515 Split lifetimes of induction variables when loops are unrolled.
2517 fsplit-stack
2518 Common Report Var(flag_split_stack) Init(-1)
2519 Generate discontiguous stack frames.
2521 fsplit-wide-types
2522 Common Report Var(flag_split_wide_types) Optimization
2523 Split wide types into independent registers.
2525 fsplit-wide-types-early
2526 Common Report Var(flag_split_wide_types_early) Optimization
2527 Split wide types into independent registers earlier.
2529 fssa-backprop
2530 Common Report Var(flag_ssa_backprop) Init(1) Optimization
2531 Enable backward propagation of use properties at the SSA level.
2533 fssa-phiopt
2534 Common Report Var(flag_ssa_phiopt) Optimization
2535 Optimize conditional patterns using SSA PHI nodes.
2537 fstdarg-opt
2538 Common Report Var(flag_stdarg_opt) Init(1) Optimization
2539 Optimize amount of stdarg registers saved to stack at start of function.
2541 fvariable-expansion-in-unroller
2542 Common Report Var(flag_variable_expansion_in_unroller) Optimization
2543 Apply variable expansion when loops are unrolled.
2545 fstack-check=
2546 Common Report RejectNegative Joined Optimization
2547 -fstack-check=[no|generic|specific]     Insert stack checking code into the program.
2549 fstack-check
2550 Common Alias(fstack-check=, specific, no)
2551 Insert stack checking code into the program.  Same as -fstack-check=specific.
2553 fstack-clash-protection
2554 Common Report Var(flag_stack_clash_protection) Optimization
2555 Insert code to probe each page of stack space as it is allocated to protect
2556 from stack-clash style attacks.
2558 fstack-limit
2559 Common Var(common_deferred_options) Defer
2561 fstack-limit-register=
2562 Common RejectNegative Joined Var(common_deferred_options) Defer
2563 -fstack-limit-register=<register>       Trap if the stack goes past <register>.
2565 fstack-limit-symbol=
2566 Common RejectNegative Joined Var(common_deferred_options) Defer
2567 -fstack-limit-symbol=<name>     Trap if the stack goes past symbol <name>.
2569 fstack-protector
2570 Common Report Var(flag_stack_protect, 1) Init(-1) Optimization
2571 Use propolice as a stack protection method.
2573 fstack-protector-all
2574 Common Report RejectNegative Var(flag_stack_protect, 2) Init(-1) Optimization
2575 Use a stack protection method for every function.
2577 fstack-protector-strong
2578 Common Report RejectNegative Var(flag_stack_protect, 3) Init(-1) Optimization
2579 Use a smart stack protection method for certain functions.
2581 fstack-protector-explicit
2582 Common Report RejectNegative Var(flag_stack_protect, 4) Optimization
2583 Use stack protection method only for functions with the stack_protect attribute.
2585 fstack-usage
2586 Common RejectNegative Var(flag_stack_usage)
2587 Output stack usage information on a per-function basis.
2589 fstrength-reduce
2590 Common Ignore
2591 Does nothing.  Preserved for backward compatibility.
2593 ; Nonzero if we should do (language-dependent) alias analysis.
2594 ; Typically, this analysis will assume that expressions of certain
2595 ; types do not alias expressions of certain other types.  Only used
2596 ; if alias analysis (in general) is enabled.
2597 fstrict-aliasing
2598 Common Report Var(flag_strict_aliasing) Optimization
2599 Assume strict aliasing rules apply.
2601 fstrict-overflow
2602 Common Report
2603 Treat signed overflow as undefined.  Negated as -fwrapv -fwrapv-pointer.
2605 fsync-libcalls
2606 Common Report Var(flag_sync_libcalls) Init(1)
2607 Implement __atomic operations via libcalls to legacy __sync functions.
2609 fsyntax-only
2610 Common Report Var(flag_syntax_only)
2611 Check for syntax errors, then stop.
2613 ftest-coverage
2614 Common Report Var(flag_test_coverage)
2615 Create data files needed by \"gcov\".
2617 fthread-jumps
2618 Common Report Var(flag_thread_jumps) Optimization
2619 Perform jump threading optimizations.
2621 ftime-report
2622 Common Report Var(time_report)
2623 Report the time taken by each compiler pass.
2625 ftime-report-details
2626 Common Report Var(time_report_details)
2627 Record times taken by sub-phases separately.
2629 ftls-model=
2630 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2631 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec]      Set the default thread-local storage code generation model.
2633 Enum
2634 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2636 EnumValue
2637 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2639 EnumValue
2640 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2642 EnumValue
2643 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2645 EnumValue
2646 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2648 ftoplevel-reorder
2649 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
2650 Reorder top level functions, variables, and asms.
2652 ftracer
2653 Common Report Var(flag_tracer) Optimization
2654 Perform superblock formation via tail duplication.
2656 ftrampolines
2657 Common Report Var(flag_trampolines) Init(0)
2658 For targets that normally need trampolines for nested functions, always
2659 generate them instead of using descriptors.
2661 ; Zero means that floating-point math operations cannot generate a
2662 ; (user-visible) trap.  This is the case, for example, in nonstop
2663 ; IEEE 754 arithmetic.
2664 ftrapping-math
2665 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
2666 Assume floating-point operations can trap.
2668 ftrapv
2669 Common Report Var(flag_trapv) Optimization
2670 Trap for signed overflow in addition, subtraction and multiplication.
2672 ftree-ccp
2673 Common Report Var(flag_tree_ccp) Optimization
2674 Enable SSA-CCP optimization on trees.
2676 ftree-bit-ccp
2677 Common Report Var(flag_tree_bit_ccp) Optimization
2678 Enable SSA-BIT-CCP optimization on trees.
2680 ftree-store-ccp
2681 Common Ignore
2682 Does nothing.  Preserved for backward compatibility.
2684 ftree-ch
2685 Common Report Var(flag_tree_ch) Optimization
2686 Enable loop header copying on trees.
2688 ftree-coalesce-inlined-vars
2689 Common Ignore RejectNegative
2690 Does nothing.  Preserved for backward compatibility.
2692 ftree-coalesce-vars
2693 Common Report Var(flag_tree_coalesce_vars) Optimization
2694 Enable SSA coalescing of user variables.
2696 ftree-copyrename
2697 Common Ignore
2698 Does nothing.  Preserved for backward compatibility.
2700 ftree-copy-prop
2701 Common Report Var(flag_tree_copy_prop) Optimization
2702 Enable copy propagation on trees.
2704 ftree-store-copy-prop
2705 Common Ignore
2706 Does nothing.  Preserved for backward compatibility.
2708 ftree-cselim
2709 Common Report Var(flag_tree_cselim) Init(2) Optimization
2710 Transform condition stores into unconditional ones.
2712 ftree-switch-conversion
2713 Common Report Var(flag_tree_switch_conversion) Optimization
2714 Perform conversions of switch initializations.
2716 ftree-dce
2717 Common Report Var(flag_tree_dce) Optimization
2718 Enable SSA dead code elimination optimization on trees.
2720 ftree-dominator-opts
2721 Common Report Var(flag_tree_dom) Optimization
2722 Enable dominator optimizations.
2724 ftree-tail-merge
2725 Common Report Var(flag_tree_tail_merge) Optimization
2726 Enable tail merging on trees.
2728 ftree-dse
2729 Common Report Var(flag_tree_dse) Optimization
2730 Enable dead store elimination.
2732 ftree-forwprop
2733 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2734 Enable forward propagation on trees.
2736 ftree-fre
2737 Common Report Var(flag_tree_fre) Optimization
2738 Enable Full Redundancy Elimination (FRE) on trees.
2740 foptimize-strlen
2741 Common Report Var(flag_optimize_strlen) Optimization
2742 Enable string length optimizations on trees.
2744 fisolate-erroneous-paths-dereference
2745 Common Report Var(flag_isolate_erroneous_paths_dereference) Optimization
2746 Detect paths that trigger erroneous or undefined behavior due to
2747 dereferencing a null pointer.  Isolate those paths from the main control
2748 flow and turn the statement with erroneous or undefined behavior into a trap.
2750 fisolate-erroneous-paths-attribute
2751 Common Report Var(flag_isolate_erroneous_paths_attribute) Optimization
2752 Detect paths that trigger erroneous or undefined behavior due to a null value
2753 being used in a way forbidden by a returns_nonnull or nonnull
2754 attribute.  Isolate those paths from the main control flow and turn the
2755 statement with erroneous or undefined behavior into a trap.
2757 ftree-loop-distribution
2758 Common Report Var(flag_tree_loop_distribution) Optimization
2759 Enable loop distribution on trees.
2761 ftree-loop-distribute-patterns
2762 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2763 Enable loop distribution for patterns transformed into a library call.
2765 ftree-loop-im
2766 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2767 Enable loop invariant motion on trees.
2769 ftree-loop-linear
2770 Common Alias(floop-nest-optimize)
2771 Enable loop nest transforms.  Same as -floop-nest-optimize.
2773 ftree-loop-ivcanon
2774 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2775 Create canonical induction variables in loops.
2777 ftree-loop-optimize
2778 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2779 Enable loop optimizations on tree level.
2781 ftree-parallelize-loops=
2782 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1) Optimization
2783 -ftree-parallelize-loops=<number>       Enable automatic parallelization of loops.
2785 ftree-phiprop
2786 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2787 Enable hoisting loads from conditional pointers.
2789 ftree-pre
2790 Common Report Var(flag_tree_pre) Optimization
2791 Enable SSA-PRE optimization on trees.
2793 ftree-partial-pre
2794 Common Report Var(flag_tree_partial_pre) Optimization
2795 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination.
2797 ftree-pta
2798 Common Report Var(flag_tree_pta) Optimization
2799 Perform function-local points-to analysis on trees.
2801 ftree-reassoc
2802 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2803 Enable reassociation on tree level.
2805 ftree-salias
2806 Common Ignore
2807 Does nothing.  Preserved for backward compatibility.
2809 ftree-sink
2810 Common Report Var(flag_tree_sink) Optimization
2811 Enable SSA code sinking on trees.
2813 ftree-slsr
2814 Common Report Var(flag_tree_slsr) Optimization
2815 Perform straight-line strength reduction.
2817 ftree-sra
2818 Common Report Var(flag_tree_sra) Optimization
2819 Perform scalar replacement of aggregates.
2821 ftree-ter
2822 Common Report Var(flag_tree_ter) Optimization
2823 Replace temporary expressions in the SSA->normal pass.
2825 ftree-lrs
2826 Common Report Var(flag_tree_live_range_split) Optimization
2827 Perform live range splitting during the SSA->normal pass.
2829 ftree-vrp
2830 Common Report Var(flag_tree_vrp) Init(0) Optimization
2831 Perform Value Range Propagation on trees.
2833 fsplit-paths
2834 Common Report Var(flag_split_paths) Init(0) Optimization
2835 Split paths leading to loop backedges.
2837 funconstrained-commons
2838 Common Var(flag_unconstrained_commons) Optimization
2839 Assume common declarations may be overridden with ones with a larger
2840 trailing array.
2842 funit-at-a-time
2843 Common Report Var(flag_unit_at_a_time) Init(1)
2844 Compile whole compilation unit at a time.
2846 funroll-loops
2847 Common Report Var(flag_unroll_loops) Optimization
2848 Perform loop unrolling when iteration count is known.
2850 funroll-all-loops
2851 Common Report Var(flag_unroll_all_loops) Optimization
2852 Perform loop unrolling for all loops.
2854 ; Nonzero means that loop optimizer may assume that the induction variables
2855 ; that control loops do not overflow and that the loops with nontrivial
2856 ; exit condition are not infinite
2857 funsafe-loop-optimizations
2858 Common Ignore
2859 Does nothing.  Preserved for backward compatibility.
2861 fassociative-math
2862 Common Report Var(flag_associative_math) SetByCombined Optimization
2863 Allow optimization for floating-point arithmetic which may change the
2864 result of the operation due to rounding.
2866 freciprocal-math
2867 Common Report Var(flag_reciprocal_math) SetByCombined Optimization
2868 Same as -fassociative-math for expressions which include division.
2870 ; Nonzero means that unsafe floating-point math optimizations are allowed
2871 ; for the sake of speed.  IEEE compliance is not guaranteed, and operations
2872 ; are allowed to assume that their arguments and results are "normal"
2873 ; (e.g., nonnegative for SQRT).
2874 funsafe-math-optimizations
2875 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2876 Allow math optimizations that may violate IEEE or ISO standards.
2878 funswitch-loops
2879 Common Report Var(flag_unswitch_loops) Optimization
2880 Perform loop unswitching.
2882 fsplit-loops
2883 Common Report Var(flag_split_loops) Optimization
2884 Perform loop splitting.
2886 fversion-loops-for-strides
2887 Common Report Var(flag_version_loops_for_strides) Optimization
2888 Version loops based on whether indices have a stride of one.
2890 funwind-tables
2891 Common Report Var(flag_unwind_tables) Optimization
2892 Just generate unwind tables for exception handling.
2894 fuse-ld=bfd
2895 Common Driver Negative(fuse-ld=gold)
2896 Use the bfd linker instead of the default linker.
2898 fuse-ld=gold
2899 Common Driver Negative(fuse-ld=bfd)
2900 Use the gold linker instead of the default linker.
2902 fuse-ld=lld
2903 Common Driver Negative(fuse-ld=lld)
2904 Use the lld LLVM linker instead of the default linker.
2906 fuse-linker-plugin
2907 Common Undocumented Var(flag_use_linker_plugin)
2909 ; Positive if we should track variables, negative if we should run
2910 ; the var-tracking pass only to discard debug annotations, zero if
2911 ; we're not to run it.  When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2912 ; will be set according to optimize, debug_info_level and debug_hooks
2913 ; in process_options ().
2914 fvar-tracking
2915 Common Report Var(flag_var_tracking) Init(2) PerFunction
2916 Perform variable tracking.
2918 ; Positive if we should track variables at assignments, negative if
2919 ; we should run the var-tracking pass only to discard debug
2920 ; annotations.  When flag_var_tracking_assignments ==
2921 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2922 fvar-tracking-assignments
2923 Common Report Var(flag_var_tracking_assignments) Init(2) PerFunction
2924 Perform variable tracking by annotating assignments.
2926 ; Nonzero if we should toggle flag_var_tracking_assignments after
2927 ; processing options and computing its default.  */
2928 fvar-tracking-assignments-toggle
2929 Common Report Var(flag_var_tracking_assignments_toggle) PerFunction
2930 Toggle -fvar-tracking-assignments.
2932 ; Positive if we should track uninitialized variables, negative if
2933 ; we should run the var-tracking pass only to discard debug
2934 ; annotations.  When flag_var_tracking_uninit == AUTODETECT_VALUE it
2935 ; will be set according to flag_var_tracking.
2936 fvar-tracking-uninit
2937 Common Report Var(flag_var_tracking_uninit) PerFunction
2938 Perform variable tracking and also tag variables that are uninitialized.
2940 ; Alias to enable both -ftree-loop-vectorize and -ftree-slp-vectorize.
2941 ftree-vectorize
2942 Common Report Optimization
2943 Enable vectorization on trees.
2945 ftree-vectorizer-verbose=
2946 Common Joined RejectNegative Ignore
2947 Does nothing.  Preserved for backward compatibility.
2949 ftree-loop-vectorize
2950 Common Report Var(flag_tree_loop_vectorize) Optimization EnabledBy(ftree-vectorize)
2951 Enable loop vectorization on trees.
2953 ftree-slp-vectorize
2954 Common Report Var(flag_tree_slp_vectorize) Optimization EnabledBy(ftree-vectorize)
2955 Enable basic block vectorization (SLP) on trees.
2957 fvect-cost-model=
2958 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT) Optimization
2959 -fvect-cost-model=[unlimited|dynamic|cheap]     Specifies the cost model for vectorization.
2961 fsimd-cost-model=
2962 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED) Optimization
2963 -fsimd-cost-model=[unlimited|dynamic|cheap]     Specifies the vectorization cost model for code marked with a simd directive.
2965 Enum
2966 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
2968 EnumValue
2969 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
2971 EnumValue
2972 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
2974 EnumValue
2975 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
2977 fvect-cost-model
2978 Common Alias(fvect-cost-model=,dynamic,unlimited)
2979 Enables the dynamic vectorizer cost model.  Preserved for backward compatibility.
2981 ftree-vect-loop-version
2982 Common Ignore
2983 Does nothing. Preserved for backward compatibility.
2985 ftree-scev-cprop
2986 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2987 Enable copy propagation of scalar-evolution information.
2989 ; -fverbose-asm causes extra commentary information to be produced in
2990 ; the generated assembly code (to make it more readable).  This option
2991 ; is generally only of use to those who actually need to read the
2992 ; generated assembly code (perhaps while debugging the compiler itself).
2993 ; -fno-verbose-asm, the default, causes the extra information
2994 ; to not be added and is useful when comparing two assembler files.
2995 fverbose-asm
2996 Common Report Var(flag_verbose_asm)
2997 Add extra commentary to assembler output.
2999 fvisibility=
3000 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
3001 -fvisibility=[default|internal|hidden|protected]        Set the default symbol visibility.
3003 Enum
3004 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
3006 EnumValue
3007 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
3009 EnumValue
3010 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
3012 EnumValue
3013 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
3015 EnumValue
3016 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
3018 fvtable-verify=
3019 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
3020 Validate vtable pointers before using them.
3022 Enum
3023 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
3025 EnumValue
3026 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
3028 EnumValue
3029 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
3031 EnumValue
3032 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
3034 fvtv-counts
3035 Common Var(flag_vtv_counts)
3036 Output vtable verification counters.
3038 fvtv-debug
3039 Common Var(flag_vtv_debug)
3040 Output vtable verification pointer sets information.
3042 fvpt
3043 Common Report Var(flag_value_profile_transformations) Optimization
3044 Use expression value profiles in optimizations.
3046 fweb
3047 Common Report Var(flag_web) Init(2) Optimization
3048 Construct webs and split unrelated uses of single variable.
3050 ftree-builtin-call-dce
3051 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
3052 Enable conditional dead code elimination for builtin calls.
3054 fwhole-program
3055 Common Report Var(flag_whole_program) Init(0)
3056 Perform whole program optimizations.
3058 fwrapv-pointer
3059 Common Report Var(flag_wrapv_pointer) Optimization
3060 Assume pointer overflow wraps around.
3062 fwrapv
3063 Common Report Var(flag_wrapv) Optimization
3064 Assume signed arithmetic overflow wraps around.
3066 fzero-initialized-in-bss
3067 Common Report Var(flag_zero_initialized_in_bss) Init(1)
3068 Put zero initialized data in the bss section.
3071 Common Driver RejectNegative JoinedOrMissing
3072 Generate debug information in default format.
3074 gas-loc-support
3075 Common Driver Var(dwarf2out_as_loc_support) Init(2)
3076 Assume assembler support for (DWARF2+) .loc directives.
3078 gas-locview-support
3079 Common Driver Var(dwarf2out_as_locview_support) Init(2)
3080 Assume assembler support for view in (DWARF2+) .loc directives.
3082 gcoff
3083 Common Driver WarnRemoved
3084 Does nothing.  Preserved for backward compatibility.
3086 gcoff1
3087 Common Driver WarnRemoved
3088 Does nothing.  Preserved for backward compatibility.
3090 gcoff2
3091 Common Driver WarnRemoved
3092 Does nothing.  Preserved for backward compatibility.
3094 gcoff3
3095 Common Driver WarnRemoved
3096 Does nothing.  Preserved for backward compatibility.
3098 gcolumn-info
3099 Common Driver Var(debug_column_info,1) Init(1)
3100 Record DW_AT_decl_column and DW_AT_call_column in DWARF.
3102 gdwarf
3103 Common Driver JoinedOrMissing Negative(gdwarf-)
3104 Generate debug information in default version of DWARF format.
3106 gdwarf-
3107 Common Driver Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
3108 Generate debug information in DWARF v2 (or later) format.
3110 ggdb
3111 Common Driver JoinedOrMissing
3112 Generate debug information in default extended format.
3114 ginline-points
3115 Common Driver Var(debug_inline_points) Init(2)
3116 Generate extended entry point information for inlined functions.
3118 ginternal-reset-location-views
3119 Common Driver Var(debug_internal_reset_location_views) Init(2)
3120 Compute locview reset points based on insn length estimates.
3122 gno-
3123 RejectNegative Joined Undocumented
3124 ; Catch the gno- prefix, so it doesn't backtrack to g<level>.
3126 gno-pubnames
3127 Common Driver Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
3128 Don't generate DWARF pubnames and pubtypes sections.
3130 gpubnames
3131 Common Driver Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
3132 Generate DWARF pubnames and pubtypes sections.
3134 ggnu-pubnames
3135 Common Driver Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
3136 Generate DWARF pubnames and pubtypes sections with GNU extensions.
3138 grecord-gcc-switches
3139 Common Driver Var(dwarf_record_gcc_switches) Init(1)
3140 Record gcc command line switches in DWARF DW_AT_producer.
3142 gsplit-dwarf
3143 Common Driver Var(dwarf_split_debug_info) Init(0)
3144 Generate debug information in separate .dwo files.
3146 gstabs
3147 Common Driver JoinedOrMissing Negative(gstabs+)
3148 Generate debug information in STABS format.
3150 gstabs+
3151 Common Driver JoinedOrMissing Negative(gvms)
3152 Generate debug information in extended STABS format.
3154 gstatement-frontiers
3155 Common Driver Var(debug_nonbind_markers_p) Init(2)
3156 Emit progressive recommended breakpoint locations.
3158 gstrict-dwarf
3159 Common Driver Report Var(dwarf_strict) Init(0)
3160 Don't emit DWARF additions beyond selected version.
3162 gdescribe-dies
3163 Common Driver Report Var(flag_describe_dies) Init(0)
3164 Add description attributes to some DWARF DIEs that have no name attribute.
3166 gtoggle
3167 Common Driver Report Var(flag_gtoggle)
3168 Toggle debug information generation.
3170 gvariable-location-views
3171 Common Driver Var(debug_variable_location_views, 1) Init(2)
3172 Augment variable location lists with progressive views.
3174 gvariable-location-views=incompat5
3175 Common Driver RejectNegative Var(debug_variable_location_views, -1) Init(2)
3177 gvms
3178 Common Driver JoinedOrMissing Negative(gxcoff)
3179 Generate debug information in VMS format.
3181 gxcoff
3182 Common Driver JoinedOrMissing Negative(gxcoff+)
3183 Generate debug information in XCOFF format.
3185 gxcoff+
3186 Common Driver JoinedOrMissing Negative(gdwarf)
3187 Generate debug information in extended XCOFF format.
3189 Enum
3190 Name(compressed_debug_sections) Type(int)
3192 ; Since -gz= is completely handled in specs, the values aren't used and we
3193 ; assign arbitrary constants.
3194 EnumValue
3195 Enum(compressed_debug_sections) String(none) Value(0)
3197 EnumValue
3198 Enum(compressed_debug_sections) String(zlib) Value(1)
3200 EnumValue
3201 Enum(compressed_debug_sections) String(zlib-gnu) Value(2)
3204 Common Driver
3205 Generate compressed debug sections.
3208 Common Driver RejectNegative Joined Enum(compressed_debug_sections)
3209 -gz=<format>    Generate compressed debug sections in format <format>.
3212 Driver Joined Separate
3214 iplugindir=
3215 Common Joined Var(plugindir_string) Init(0)
3216 -iplugindir=<dir>       Set <dir> to be the default plugin directory.
3218 imultiarch
3219 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
3220 -imultiarch <dir>       Set <dir> to be the multiarch include subdirectory.
3223 Driver Joined Separate
3226 Driver
3228 no-canonical-prefixes
3229 Driver
3231 nodefaultlibs
3232 Driver
3234 nostartfiles
3235 Driver
3237 nolibc
3238 Driver
3240 nostdlib
3241 Driver
3244 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
3245 -o <file>       Place output into <file>.
3248 Common Var(profile_flag)
3249 Enable function profiling.
3251 pass-exit-codes
3252 Driver Var(pass_exit_codes)
3254 pedantic
3255 Common Alias(Wpedantic)
3257 pedantic-errors
3258 Common Var(flag_pedantic_errors)
3259 Like -pedantic but issue them as errors.
3262 Driver
3264 pipe
3265 Driver Var(use_pipes)
3267 print-file-name=
3268 Driver JoinedOrMissing Var(print_file_name)
3270 print-libgcc-file-name
3271 Driver
3273 print-multi-directory
3274 Driver Var(print_multi_directory)
3276 print-multi-lib
3277 Driver Var(print_multi_lib)
3279 print-multi-os-directory
3280 Driver Var(print_multi_os_directory)
3282 print-multiarch
3283 Driver Var(print_multiarch)
3285 print-prog-name=
3286 Driver JoinedOrMissing Var(print_prog_name)
3288 print-search-dirs
3289 Driver Var(print_search_dirs)
3291 print-sysroot
3292 Driver Var(print_sysroot)
3294 print-sysroot-headers-suffix
3295 Driver Var(print_sysroot_headers_suffix)
3297 quiet
3298 Common Var(quiet_flag) RejectDriver
3299 Do not display functions compiled or elapsed time.
3302 Driver
3305 Driver
3307 save-temps
3308 Driver
3310 save-temps=
3311 Driver Joined
3314 Driver
3316 time
3317 Driver Var(report_times)
3319 time=
3320 Driver JoinedOrMissing
3323 Driver Joined Separate
3325 undef
3326 Driver
3327 ; C option, but driver must not handle as "-u ndef".
3330 Common Driver Var(verbose_flag)
3331 Enable verbose output.
3333 version
3334 Common Var(version_flag) RejectDriver
3335 Display the compiler's version.
3338 Common Var(inhibit_warnings)
3339 Suppress warnings.
3341 wrapper
3342 Driver Separate Var(wrapper_string)
3345 Driver Joined Separate
3347 shared
3348 Driver RejectNegative Negative(static-pie)
3349 Create a shared library.
3351 shared-libgcc
3352 Driver
3354 specs
3355 Driver Separate Alias(specs=)
3357 specs=
3358 Driver Joined
3360 static
3361 Driver
3363 static-libgcc
3364 Driver
3366 static-libgfortran
3367 Driver
3368 ; Documented for Fortran, but always accepted by driver.
3370 static-libstdc++
3371 Driver
3373 static-libgo
3374 Driver
3375 ; Documented for Go, but always accepted by driver.
3377 static-libasan
3378 Driver
3380 static-libtsan
3381 Driver
3383 static-liblsan
3384 Driver
3386 static-libubsan
3387 Driver
3389 symbolic
3390 Driver
3392 no-pie
3393 Driver RejectNegative Negative(shared)
3394 Don't create a dynamically linked position independent executable.
3397 Driver RejectNegative Negative(no-pie)
3398 Create a dynamically linked position independent executable.
3400 static-pie
3401 Driver RejectNegative Negative(pie)
3402 Create a static position independent executable.
3405 Driver Joined Separate
3407 fipa-ra
3408 Common Report Var(flag_ipa_ra) Optimization
3409 Use caller save register across calls if possible.
3411 ; This comment is to ensure we retain the blank line above.