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1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003-2019 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 Variable
67 int *param_values
69 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
70 Variable
71 int flag_generate_lto
73 ; Nonzero if we should write GIMPLE bytecode for offload compilation.
74 Variable
75 int flag_generate_offload = 0
77 ; Nonzero means we should be saving declaration info into a .X file.
78 Variable
79 int flag_gen_aux_info = 0
81 ; Nonzero if we are compiling code for a shared library, zero for
82 ; executable.
83 Variable
84 int flag_shlib
86 ; These two are really VEC(char_p,heap) *.
88 Variable
89 void *flag_instrument_functions_exclude_functions
91 Variable
92 void *flag_instrument_functions_exclude_files
94 ; Generic structs (e.g. templates not explicitly specialized)
95 ; may not have a compilation unit associated with them, and so
96 ; may need to be treated differently from ordinary structs.
98 ; Structs only handled by reference (indirectly), will also usually
99 ; not need as much debugging information.
101 Variable
102 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
104 Variable
105 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
107 ; True if we should exit after parsing options.
108 Variable
109 bool exit_after_options
111 ; Type(s) of debugging information we are producing (if any).  See
112 ; flag-types.h for the definitions of the different possible types of
113 ; debugging information.
114 Variable
115 enum debug_info_type write_symbols = NO_DEBUG
117 ; Level of debugging information we are producing.  See flag-types.h
118 ; for the definitions of the different possible levels.
119 Variable
120 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
122 ; Nonzero means use GNU-only extensions in the generated symbolic
123 ; debugging information.  Currently, this only has an effect when
124 ; write_symbols is set to DBX_DEBUG or XCOFF_DEBUG.
125 Variable
126 bool use_gnu_debug_info_extensions
128 ; Original value of maximum field alignment in bytes, specified via
129 ; -fpack-struct=<value>.
130 Variable
131 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
133 ; Type of stack check.
134 Variable
135 enum stack_check_type flag_stack_check = NO_STACK_CHECK
137 ; True if stack usage information needs to be computed.
138 Variable
139 bool flag_stack_usage_info = false
141 ; -dA causes debug commentary information to be produced in
142 ; the generated assembly code (to make it more readable).  This option
143 ; is generally only of use to those who actually need to read the
144 ; generated assembly code (perhaps while debugging the compiler itself).
145 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
146 ; to be a catchall for printing debug information in the assembler file.
147 Variable
148 int flag_debug_asm
150 ; How many NOP insns to place at each function entry by default
151 Variable
152 HOST_WIDE_INT function_entry_patch_area_size
154 ; And how far the real asm entry point is into this area
155 Variable
156 HOST_WIDE_INT function_entry_patch_area_start
158 ; Balance between GNAT encodings and standard DWARF to emit.
159 Variable
160 enum dwarf_gnat_encodings gnat_encodings = DWARF_GNAT_ENCODINGS_DEFAULT
162 ; -dP causes the rtl to be emitted as a comment in assembly.
163 Variable
164 int flag_dump_rtl_in_asm
166 ; Whether -da was passed (used only in handle_common_deferred_options).
167 Variable
168 bool flag_dump_all_passed
170 ; Other flags saying which kinds of debugging dump have been requested.
172 Variable
173 int rtl_dump_and_exit
175 Variable
176 int flag_print_asm_name
178 ; Name of top-level original source file (what was input to cpp).
179 ; This comes from the #-command at the beginning of the actual input.
180 ; If there isn't any there, then this is the cc1 input file name.
181 Variable
182 const char *main_input_filename
184 ; Pointer to base name in main_input_filename, with directories and a
185 ; single final extension removed, and the length of this base
186 ; name.
188 Variable
189 const char *main_input_basename
191 Variable
192 int main_input_baselength
194 ; Which options have been printed by --help.
195 Variable
196 char *help_printed
198 ; Which enums have been printed by --help.  0 = not printed, no
199 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
200 ; = printed.
201 Variable
202 char *help_enum_printed
204 ; The number of columns for --help output.
205 Variable
206 unsigned int help_columns
208 ; Whether this options structure has been through finish_options
209 Variable
210 bool flag_opts_finished
212 ; What the sanitizer should instrument
213 Variable
214 unsigned int flag_sanitize
216 ; What sanitizers should recover from errors
217 Variable
218 unsigned int flag_sanitize_recover = (SANITIZE_UNDEFINED | SANITIZE_UNDEFINED_NONDEFAULT | SANITIZE_KERNEL_ADDRESS) & ~(SANITIZE_UNREACHABLE | SANITIZE_RETURN)
220 ; What the coverage sanitizers should instrument
221 Variable
222 unsigned int flag_sanitize_coverage
224 ; Flag whether a prefix has been added to dump_base_name
225 Variable
226 bool dump_base_name_prefixed = false
228 ; Flag whether HSA generation has been explicitely disabled
229 Variable
230 bool flag_disable_hsa = false
233 Driver
235 -assemble
236 Driver Alias(S)
238 -compile
239 Driver Alias(c)
241 -completion=
242 Common Driver Joined Undocumented
243 Provide bash completion for options starting with provided string.
245 -coverage
246 Driver Alias(coverage)
248 -debug
249 Common Alias(g)
251 -dump
252 Common Separate Alias(d)
254 -dump=
255 Common Joined Alias(d)
257 -dumpbase
258 Common Separate Alias(dumpbase)
260 -dumpdir
261 Common Separate Alias(dumpdir)
263 -entry
264 Driver Separate Alias(e)
266 -entry=
267 Driver Joined Alias(e)
269 -extra-warnings
270 Common Warning Alias(Wextra)
272 -for-assembler
273 Driver Separate Alias(Xassembler)
275 -for-assembler=
276 Driver JoinedOrMissing Alias(Xassembler)
278 -for-linker
279 Driver Separate Alias(Xlinker)
281 -for-linker=
282 Driver JoinedOrMissing Alias(Xlinker)
284 -force-link
285 Driver Separate Alias(u)
287 -force-link=
288 Driver Joined Alias(u)
290 -help
291 Common Driver Var(help_flag)
292 Display this information.
294 -help=
295 Common Driver Report Joined
296 --help=<class>  Display descriptions of a specific class of options.  <class> is one or more of optimizers, target, warnings, undocumented, params.
298 -language
299 Driver Separate Alias(x)
301 -language=
302 Driver Joined Alias(x)
304 -library-directory
305 Driver Separate Alias(L)
307 -library-directory=
308 Driver Joined Alias(L)
310 -no-canonical-prefixes
311 Driver Alias(no-canonical-prefixes)
313 -no-standard-libraries
314 Driver Alias(nostdlib)
316 -no-sysroot-suffix
317 Driver Var(no_sysroot_suffix)
319 -no-warnings
320 Common Alias(w)
322 -optimize
323 Common Alias(O)
325 -output
326 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
328 -output=
329 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
331 -pass-exit-codes
332 Driver Alias(pass-exit-codes)
334 -pedantic
335 Common Alias(Wpedantic)
337 -pedantic-errors
338 Common Alias(pedantic-errors)
340 -pie
341 Driver Alias(pie)
343 -static-pie
344 Driver Alias(static-pie)
346 -pipe
347 Driver Alias(pipe)
349 -prefix
350 Driver Separate Alias(B)
352 -prefix=
353 Driver JoinedOrMissing Alias(B)
355 -preprocess
356 Driver Alias(E)
358 -print-file-name
359 Driver Separate Alias(print-file-name=)
361 -print-file-name=
362 Driver JoinedOrMissing Alias(print-file-name=)
364 -print-libgcc-file-name
365 Driver Alias(print-libgcc-file-name)
367 -print-multi-directory
368 Driver Alias(print-multi-directory)
370 -print-multi-lib
371 Driver Alias(print-multi-lib)
373 -print-multi-os-directory
374 Driver Alias(print-multi-os-directory)
376 -print-multiarch
377 Driver Alias(print-multiarch)
379 -print-prog-name
380 Driver Separate Alias(print-prog-name=)
382 -print-prog-name=
383 Driver JoinedOrMissing Alias(print-prog-name=)
385 -print-search-dirs
386 Driver Alias(print-search-dirs)
388 -print-sysroot
389 Driver Alias(print-sysroot)
391 -print-sysroot-headers-suffix
392 Driver Alias(print-sysroot-headers-suffix)
394 -profile
395 Common Alias(p)
397 -save-temps
398 Driver Alias(save-temps)
400 -shared
401 Driver Alias(shared)
403 -specs
404 Driver Separate Alias(specs=)
406 -specs=
407 Driver Joined Alias(specs=)
409 -static
410 Driver Alias(static)
412 -symbolic
413 Driver Alias(symbolic)
415 -target-help
416 Common Driver
417 Alias for --help=target.
419 -time
420 Driver Alias(time)
422 -verbose
423 Driver Alias(v)
425 ;; The driver used to convert options such as --help into forms such
426 ;; as -fhelp; the following four entries are for compatibility with
427 ;; any direct uses of those (undocumented) -f forms
428 fhelp
429 Common Driver Alias(-help)
431 fhelp=
432 Common Driver Joined Alias(-help=)
434 ftarget-help
435 Common Driver Alias(-target-help)
437 fversion
438 Common Driver Alias(-version)
440 -param
441 Common Separate
442 --param <param>=<value> Set parameter <param> to value.  See below for a complete list of parameters.
444 -param=
445 Common Joined Alias(-param)
447 -sysroot
448 Driver Separate Alias(-sysroot=)
450 -sysroot=
451 Driver JoinedOrMissing
453 -version
454 Common Driver
457 Driver Joined Separate
460 Driver
463 Driver Joined Separate
466 Driver
469 Common JoinedOrMissing Optimization
470 -O<number>      Set optimization level to <number>.
473 Common Optimization
474 Optimize for space rather than speed.
476 Ofast
477 Common Optimization
478 Optimize for speed disregarding exact standards compliance.
481 Common Optimization
482 Optimize for debugging experience rather than speed or size.
485 Driver
488 Driver Negative(Qy)
491 Driver Negative(Qn)
494 Driver Joined Separate
497 Driver
500 Driver Joined Separate
502 Tbss
503 Driver Separate
505 Tbss=
506 Driver Joined
508 Tdata
509 Driver Separate
511 Tdata=
512 Driver Joined
514 Ttext
515 Driver Separate
517 Ttext=
518 Driver Joined
521 Common RejectNegative Warning Alias(Wextra)
522 This switch is deprecated; use -Wextra instead.
525 Driver JoinedOrMissing RejectNegative
528 Driver JoinedOrMissing RejectNegative
531 Driver JoinedOrMissing RejectNegative
533 Waggregate-return
534 Common Var(warn_aggregate_return) Warning
535 Warn about returning structures, unions or arrays.
537 Waggressive-loop-optimizations
538 Common Var(warn_aggressive_loop_optimizations) Init(1) Warning
539 Warn if a loop with constant number of iterations triggers undefined behavior.
541 Warray-bounds
542 Common Var(warn_array_bounds) Warning
543 Warn if an array is accessed out of bounds.
545 Warray-bounds=
546 Common Joined RejectNegative UInteger Var(warn_array_bounds) Warning IntegerRange(0, 2)
547 Warn if an array is accessed out of bounds.
549 Wattributes
550 Common Var(warn_attributes) Init(1) Warning
551 Warn about inappropriate attribute usage.
553 Wattribute-alias
554 Common Alias(Wattribute_alias=, 1, 0) Warning
555 Warn about type safety and similar errors and mismatches in declarations with alias attributes.
557 Wattribute-alias=
558 Common Joined RejectNegative UInteger Var(warn_attribute_alias) Init(1) Warning IntegerRange(0, 2)
559 Warn about type safety and similar errors and mismatches in declarations with alias attributes.
561 Wcannot-profile
562 Common Var(warn_cannot_profile) Init(1) Warning
563 Warn when profiling instrumentation was requested, but could not be applied to
564 a certain function.
566 Wcast-align
567 Common Var(warn_cast_align) Warning
568 Warn about pointer casts which increase alignment.
570 Wcast-align=strict
571 Common Var(warn_cast_align,2) Warning
572 Warn about pointer casts which increase alignment.
574 Wcpp
575 Common Var(warn_cpp) Init(1) Warning
576 Warn when a #warning directive is encountered.
578 Wattribute-warning
579 Common Var(warn_attribute_warning) Init(1) Warning
580 Warn about uses of __attribute__((warning)) declarations.
582 Wdeprecated
583 Common Var(warn_deprecated) Init(1) Warning
584 Warn if a deprecated compiler feature, class, method, or field is used.
586 Wdeprecated-declarations
587 Common Var(warn_deprecated_decl) Init(1) Warning
588 Warn about uses of __attribute__((deprecated)) declarations.
590 Wdisabled-optimization
591 Common Var(warn_disabled_optimization) Warning
592 Warn when an optimization pass is disabled.
594 Werror
595 Common Var(warnings_are_errors)
596 Treat all warnings as errors.
598 Werror=
599 Common Joined
600 Treat specified warning as error.
602 Wextra
603 Common Var(extra_warnings) Warning
604 Print extra (possibly unwanted) warnings.
606 Wfatal-errors
607 Common Var(flag_fatal_errors)
608 Exit on the first error occurred.
610 Wframe-larger-than=
611 Common RejectNegative Joined Host_Wide_Int ByteSize Warning Var(warn_frame_larger_than_size) Init(HOST_WIDE_INT_MAX)
612 -Wframe-larger-than=<byte-size> Warn if a function's stack frame requires in excess of <byte-size>.
614 Wfree-nonheap-object
615 Common Var(warn_free_nonheap_object) Init(1) Warning
616 Warn when attempting to free a non-heap object.
618 Whsa
619 Common Var(warn_hsa) Init(1) Warning
620 Warn when a function cannot be expanded to HSAIL.
622 Wimplicit-fallthrough
623 Common Alias(Wimplicit-fallthrough=,3,0) Warning
625 Wimplicit-fallthrough=
626 Common Var(warn_implicit_fallthrough) RejectNegative Joined UInteger Warning IntegerRange(0, 5)
627 Warn when a switch case falls through.
629 Winline
630 Common Var(warn_inline) Warning
631 Warn when an inlined function cannot be inlined.
633 Winvalid-memory-model
634 Common Var(warn_invalid_memory_model) Init(1) Warning
635 Warn when an atomic memory model parameter is known to be outside the valid range.
637 Wlarger-than-
638 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
640 Wlarger-than=
641 Common RejectNegative Joined Host_Wide_Int ByteSize Warning Var(warn_larger_than_size) Init(HOST_WIDE_INT_MAX)
642 -Wlarger-than=<byte-size>       Warn if an object's size exceeds <byte-size>.
644 Wnonnull-compare
645 Var(warn_nonnull_compare) Warning
646 Warn if comparing pointer parameter with nonnull attribute with NULL.
648 Wnull-dereference
649 Common Var(warn_null_dereference) Warning
650 Warn if dereferencing a NULL pointer may lead to erroneous or undefined behavior.
652 Wunsafe-loop-optimizations
653 Common Ignore Warning
654 Does nothing. Preserved for backward compatibility.
656 Wmissing-noreturn
657 Common Warning Alias(Wsuggest-attribute=noreturn)
659 Wodr
660 Common Var(warn_odr_violations) Init(1) Warning
661 Warn about some C++ One Definition Rule violations during link time optimization.
663 Woverflow
664 Common Var(warn_overflow) Init(1) Warning
665 Warn about overflow in arithmetic expressions.
667 Wlto-type-mismatch
668 Common Var(warn_lto_type_mismatch) Init(1) Warning
669 During link time optimization warn about mismatched types of global declarations.
671 Wpacked
672 Common Var(warn_packed) Warning
673 Warn when the packed attribute has no effect on struct layout.
675 Wpadded
676 Common Var(warn_padded) Warning
677 Warn when padding is required to align structure members.
679 Wpedantic
680 Common Var(pedantic) Init(0) Warning
681 Issue warnings needed for strict compliance to the standard.
683 Wreturn-local-addr
684 Common Var(warn_return_local_addr) Init(1) Warning
685 Warn about returning a pointer/reference to a local or temporary variable.
687 Wshadow
688 Common Var(warn_shadow) Warning
689 Warn when one variable shadows another.  Same as -Wshadow=global.
691 Wshadow=global
692 Common Warning Alias(Wshadow)
693 Warn when one variable shadows another (globally).
695 Wshadow=local
696 Common Var(warn_shadow_local) Warning EnabledBy(Wshadow)
697 Warn when one local variable shadows another local variable or parameter.
699 Wshadow-local
700 Common Warning Undocumented Alias(Wshadow=local)
702 Wshadow=compatible-local
703 Common Var(warn_shadow_compatible_local) Warning EnabledBy(Wshadow=local)
704 Warn when one local variable shadows another local variable or parameter of compatible type.
706 Wshadow-compatible-local
707 Common Warning Undocumented Alias(Wshadow=compatible-local)
709 Wstack-protector
710 Common Var(warn_stack_protect) Warning
711 Warn when not issuing stack smashing protection for some reason.
713 Wstack-usage=
714 Common Joined RejectNegative Host_Wide_Int ByteSize Var(warn_stack_usage) Warning Init(HOST_WIDE_INT_MAX)
715 -Wstack-usage=<byte-size>       Warn if stack usage might exceed <byte-size>.
717 Wstrict-aliasing
718 Common Warning
719 Warn about code which might break strict aliasing rules.
721 Wstrict-aliasing=
722 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
723 Warn about code which might break strict aliasing rules.
725 Wstrict-overflow
726 Common Warning
727 Warn about optimizations that assume that signed overflow is undefined.
729 Wstrict-overflow=
730 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
731 Warn about optimizations that assume that signed overflow is undefined.
733 Wsuggest-attribute=cold
734 Common Var(warn_suggest_attribute_cold) Warning
735 Warn about functions which might be candidates for __attribute__((cold)).
737 Wsuggest-attribute=const
738 Common Var(warn_suggest_attribute_const) Warning
739 Warn about functions which might be candidates for __attribute__((const)).
741 Wsuggest-attribute=pure
742 Common Var(warn_suggest_attribute_pure) Warning
743 Warn about functions which might be candidates for __attribute__((pure)).
745 Wsuggest-attribute=noreturn
746 Common Var(warn_suggest_attribute_noreturn) Warning
747 Warn about functions which might be candidates for __attribute__((noreturn)).
749 Wsuggest-attribute=malloc
750 Common Var(warn_suggest_attribute_malloc) Warning
751 Warn about functions which might be candidates for __attribute__((malloc)).
753 Wsuggest-final-types
754 Common Var(warn_suggest_final_types) Warning
755 Warn about C++ polymorphic types where adding final keyword would improve code quality.
757 Wsuggest-final-methods
758 Common Var(warn_suggest_final_methods) Warning
759 Warn about C++ virtual methods where adding final keyword would improve code quality.
761 Wswitch-unreachable
762 Common Var(warn_switch_unreachable) Warning Init(1)
763 Warn about statements between switch's controlling expression and the first
764 case.
766 Wsystem-headers
767 Common Var(warn_system_headers) Warning
768 Do not suppress warnings from system headers.
770 Wtrampolines
771 Common Var(warn_trampolines) Warning
772 Warn whenever a trampoline is generated.
774 Wtype-limits
775 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
776 Warn if a comparison is always true or always false due to the limited range of the data type.
778 Wuninitialized
779 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
780 Warn about uninitialized automatic variables.
782 Wmaybe-uninitialized
783 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
784 Warn about maybe uninitialized automatic variables.
786 Wunreachable-code
787 Common Ignore Warning
788 Does nothing. Preserved for backward compatibility.
790 Wunused
791 Common Var(warn_unused) Init(0) Warning
792 Enable all -Wunused- warnings.
794 Wunused-but-set-parameter
795 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
796 Warn when a function parameter is only set, otherwise unused.
798 Wunused-but-set-variable
799 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
800 Warn when a variable is only set, otherwise unused.
802 Wunused-function
803 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
804 Warn when a function is unused.
806 Wunused-label
807 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
808 Warn when a label is unused.
810 Wunused-parameter
811 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
812 Warn when a function parameter is unused.
814 Wunused-value
815 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
816 Warn when an expression value is unused.
818 Wunused-variable
819 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
820 Warn when a variable is unused.
822 Wcoverage-mismatch
823 Common Var(warn_coverage_mismatch) Init(1) Warning
824 Warn in case profiles in -fprofile-use do not match.
826 Wmissing-profile
827 Common Var(warn_missing_profile) Init(1) Warning
828 Warn in case profiles in -fprofile-use do not exist.
830 Wvector-operation-performance
831 Common Var(warn_vector_operation_performance) Warning
832 Warn when a vector operation is compiled outside the SIMD.
834 Xassembler
835 Driver Separate
837 Xlinker
838 Driver Separate
840 Xpreprocessor
841 Driver Separate
844 Driver
846 aux-info
847 Common Separate Var(aux_info_file_name)
848 -aux-info <file>        Emit declaration information into <file>.
850 aux-info=
851 Common Joined Alias(aux-info)
853 auxbase
854 Common Separate RejectDriver Var(aux_base_name)
856 auxbase-strip
857 Common Separate RejectDriver
859 coverage
860 Driver
863 Driver
866 Common Joined
867 -d<letters>     Enable dumps from specific passes of the compiler.
869 dumpbase
870 Common Separate Var(dump_base_name)
871 -dumpbase <file>        Set the file basename to be used for dumps.
873 dumpdir
874 Common Separate Var(dump_dir_name)
875 -dumpdir <dir>  Set the directory name to be used for dumps.
877 dumpmachine
878 Driver
880 dumpspecs
881 Driver
883 dumpversion
884 Driver
886 dumpfullversion
887 Driver
890 Driver Joined Separate
892 ; This option has historically been passed down to the linker by an
893 ; accident of a %{e*} spec, so ensure it continues to be passed down
894 ; as a single option.  The supported option for this purpose is
895 ; -rdynamic.  See PR 47390.
896 export-dynamic
897 Driver Undocumented
899 ; The version of the C++ ABI in use.  The following values are allowed:
901 ; 0: The version of the ABI believed most conformant with the C++ ABI
902 ;    specification.  This ABI may change as bugs are discovered and fixed.
903 ;    Therefore, 0 will not necessarily indicate the same ABI in different
904 ;    versions of G++.
906 ; 1: The version of the ABI first used in G++ 3.2.  No longer selectable.
908 ; 2: The version of the ABI first used in G++ 3.4, and the default
909 ;    until GCC 4.9.
911 ; 3: The version of the ABI that fixes the missing underscore
912 ;    in template non-type arguments of pointer type.
914 ; 4: The version of the ABI that introduces unambiguous mangling of
915 ;    vector types.  First selectable in G++ 4.5.
917 ; 5: The version of the ABI that ignores attribute const/noreturn
918 ;    in function pointer mangling, and corrects mangling of decltype and
919 ;    function parameters used in other parameters and the return type.
920 ;    First selectable in G++ 4.6.
922 ; 6: The version of the ABI that doesn't promote scoped enums to int and
923 ;    changes the mangling of template argument packs, const/static_cast,
924 ;    prefix ++ and --, and a class scope function used as a template
925 ;    argument.
926 ;    First selectable in G++ 4.7.
928 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
929 ;    corrects the mangling of lambdas in default argument scope.
930 ;    First selectable in G++ 4.8.
932 ; 8: The version of the ABI that corrects the substitution behavior of
933 ;    function types with function-cv-qualifiers.
934 ;    First selectable in G++ 4.9 and default in G++ 5.
936 ; 9: The version of the ABI that corrects the alignment of nullptr_t.
937 ;    First selectable and default in G++ 5.2.
939 ; 10: The version of the ABI that mangles attributes that affect type
940 ;     identity, such as ia32 calling convention attributes (stdcall, etc.)
941 ;     Default in G++ 6 (set in c_common_post_options).
943 ; 11: The version of the ABI that corrects mangling of sizeof... expressions
944 ;     and introduces new inheriting constructor handling.
945 ;     Default in G++ 7.
947 ; 12: Corrects the calling convention for classes with only deleted copy/move
948 ;     constructors and changes passing/returning of empty records.
949 ;     Default in G++ 8.1.
951 ; 13: Fixes the accidental change in 12 to the calling convention for classes
952 ;     with deleted copy constructor and trivial move constructor.
953 ;     Default in G++ 8.2.
955 ; Additional positive integers will be assigned as new versions of
956 ; the ABI become the default version of the ABI.
957 fabi-version=
958 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(0)
959 The version of the C++ ABI in use.
961 faggressive-loop-optimizations
962 Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1)
963 Aggressively optimize loops using language constraints.
965 falign-functions
966 Common Report Var(flag_align_functions) Optimization
967 Align the start of functions.
969 falign-functions=
970 Common RejectNegative Joined Var(str_align_functions) Optimization
972 flimit-function-alignment
973 Common Report Var(flag_limit_function_alignment) Optimization Init(0)
975 falign-jumps
976 Common Report Var(flag_align_jumps) Optimization
977 Align labels which are only reached by jumping.
979 falign-jumps=
980 Common RejectNegative Joined Var(str_align_jumps) Optimization
982 falign-labels
983 Common Report Var(flag_align_labels) Optimization
984 Align all labels.
986 falign-labels=
987 Common RejectNegative Joined Var(str_align_labels) Optimization
989 falign-loops
990 Common Report Var(flag_align_loops) Optimization
991 Align the start of loops.
993 falign-loops=
994 Common RejectNegative Joined Var(str_align_loops) Optimization
996 fargument-alias
997 Common Ignore
998 Does nothing. Preserved for backward compatibility.
1000 fargument-noalias
1001 Common Ignore
1002 Does nothing. Preserved for backward compatibility.
1004 fargument-noalias-global
1005 Common Ignore
1006 Does nothing. Preserved for backward compatibility.
1008 fargument-noalias-anything
1009 Common Ignore
1010 Does nothing. Preserved for backward compatibility.
1012 fsanitize=
1013 Common Driver Report Joined
1014 Select what to sanitize.
1016 fsanitize-coverage=
1017 Common Report Joined
1018 Select type of coverage sanitization.
1020 fasan-shadow-offset=
1021 Common Joined RejectNegative Var(common_deferred_options) Defer
1022 -fasan-shadow-offset=<number>   Use custom shadow memory offset.
1024 fsanitize-sections=
1025 Common Joined RejectNegative Var(common_deferred_options) Defer
1026 -fsanitize-sections=<sec1,sec2,...>     Sanitize global variables
1027 in user-defined sections.
1029 fsanitize-recover=
1030 Common Report Joined
1031 After diagnosing undefined behavior attempt to continue execution.
1033 fsanitize-recover
1034 Common Report
1035 This switch is deprecated; use -fsanitize-recover= instead.
1037 fsanitize-address-use-after-scope
1038 Common Driver Report Var(flag_sanitize_address_use_after_scope) Init(0)
1040 fsanitize-undefined-trap-on-error
1041 Common Driver Report Var(flag_sanitize_undefined_trap_on_error) Init(0)
1042 Use trap instead of a library function for undefined behavior sanitization.
1044 fasynchronous-unwind-tables
1045 Common Report Var(flag_asynchronous_unwind_tables) Optimization
1046 Generate unwind tables that are exact at each instruction boundary.
1048 fauto-inc-dec
1049 Common Report Var(flag_auto_inc_dec) Init(1) Optimization
1050 Generate auto-inc/dec instructions.
1052 fauto-profile
1053 Common Report Var(flag_auto_profile)
1054 Use sample profile information for call graph node weights. The default
1055 profile file is fbdata.afdo in 'pwd'.
1057 fauto-profile=
1058 Common Joined RejectNegative Var(auto_profile_file)
1059 Use sample profile information for call graph node weights. The profile
1060 file is specified in the argument.
1062 ; -fcheck-bounds causes gcc to generate array bounds checks.
1063 ; For C, C++ and ObjC: defaults off.
1064 ; For Java: defaults to on.
1065 ; For Fortran: defaults to off.
1066 fbounds-check
1067 Common Report Var(flag_bounds_check)
1068 Generate code to check bounds before indexing arrays.
1070 fbranch-count-reg
1071 Common Report Var(flag_branch_on_count_reg) Optimization
1072 Replace add, compare, branch with branch on count register.
1074 fbranch-probabilities
1075 Common Report Var(flag_branch_probabilities) Optimization
1076 Use profiling information for branch probabilities.
1078 fbranch-target-load-optimize
1079 Common Ignore
1080 Does nothing.  Preserved for backward compatibility.
1082 fbranch-target-load-optimize2
1083 Common Ignore
1084 Does nothing.  Preserved for backward compatibility.
1086 fbtr-bb-exclusive
1087 Common Ignore
1088 Does nothing.  Preserved for backward compatibility.
1090 fcall-saved-
1091 Common Joined RejectNegative Var(common_deferred_options) Defer
1092 -fcall-saved-<register> Mark <register> as being preserved across functions.
1094 fcall-used-
1095 Common Joined RejectNegative Var(common_deferred_options) Defer
1096 -fcall-used-<register>  Mark <register> as being corrupted by function calls.
1098 ; Nonzero for -fcaller-saves: allocate values in regs that need to
1099 ; be saved across function calls, if that produces overall better code.
1100 ; Optional now, so people can test it.
1101 fcaller-saves
1102 Common Report Var(flag_caller_saves) Optimization
1103 Save registers around function calls.
1105 fcheck-data-deps
1106 Common Ignore
1107 This switch is deprecated; do not use.
1109 fcheck-new
1110 Common Var(flag_check_new)
1111 Check the return value of new in C++.
1113 fchecking
1114 Common Var(flag_checking) Init(CHECKING_P ? ENABLE_EXTRA_CHECKING ? 2 : 1 : 0)
1115 Perform internal consistency checkings.
1117 fchecking=
1118 Common Joined RejectNegative UInteger Var(flag_checking)
1119 Perform internal consistency checkings.
1121 fcode-hoisting
1122 Common Report Var(flag_code_hoisting) Optimization
1123 Enable code hoisting.
1125 fcombine-stack-adjustments
1126 Common Report Var(flag_combine_stack_adjustments) Optimization
1127 Looks for opportunities to reduce stack adjustments and stack references.
1129 fcommon
1130 Common Report Var(flag_no_common,0)
1131 Do not put uninitialized globals in the common section.
1133 fcompare-debug
1134 Driver
1135 ; Converted by the driver to -fcompare-debug= options.
1137 fcompare-debug=
1138 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
1139 -fcompare-debug[=<opts>]        Compile with and without e.g. -gtoggle, and compare the final-insns dump.
1141 fcompare-debug-second
1142 Common Driver RejectNegative Var(flag_compare_debug)
1143 Run only the second compilation of -fcompare-debug.
1145 fcompare-elim
1146 Common Report Var(flag_compare_elim_after_reload) Optimization
1147 Perform comparison elimination after register allocation has finished.
1149 fconserve-stack
1150 Common Var(flag_conserve_stack) Optimization
1151 Do not perform optimizations increasing noticeably stack usage.
1153 fcprop-registers
1154 Common Report Var(flag_cprop_registers) Optimization
1155 Perform a register copy-propagation optimization pass.
1157 fcrossjumping
1158 Common Report Var(flag_crossjumping) Optimization
1159 Perform cross-jumping optimization.
1161 fcse-follow-jumps
1162 Common Report Var(flag_cse_follow_jumps) Optimization
1163 When running CSE, follow jumps to their targets.
1165 fcse-skip-blocks
1166 Common Ignore
1167 Does nothing.  Preserved for backward compatibility.
1169 fcx-limited-range
1170 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
1171 Omit range reduction step when performing complex division.
1173 fcx-fortran-rules
1174 Common Report Var(flag_cx_fortran_rules) Optimization
1175 Complex multiplication and division follow Fortran rules.
1177 fdata-sections
1178 Common Report Var(flag_data_sections)
1179 Place data items into their own section.
1181 fdbg-cnt-list
1182 Common Report Var(common_deferred_options) Defer
1183 List all available debugging counters with their limits and counts.
1185 fdbg-cnt=
1186 Common RejectNegative Joined Var(common_deferred_options) Defer
1187 -fdbg-cnt=<counter>[:<lower_limit>]:<upper_limit>[,<counter>:...]       Set the debug counter limit.
1189 fdebug-prefix-map=
1190 Common Joined RejectNegative Var(common_deferred_options) Defer
1191 -fdebug-prefix-map=<old>=<new> Map one directory name to another in debug information.
1193 ffile-prefix-map=
1194 Common Joined RejectNegative Var(common_deferred_options) Defer
1195 -ffile-prefix-map=<old>=<new> Map one directory name to another in compilation result.
1197 fdebug-types-section
1198 Common Report Var(flag_debug_types_section) Init(0)
1199 Output .debug_types section when using DWARF v4 debuginfo.
1201 ; Nonzero for -fdefer-pop: don't pop args after each function call
1202 ; instead save them up to pop many calls' args with one insns.
1203 fdefer-pop
1204 Common Report Var(flag_defer_pop) Optimization
1205 Defer popping functions args from stack until later.
1207 fdelayed-branch
1208 Common Report Var(flag_delayed_branch) Optimization
1209 Attempt to fill delay slots of branch instructions.
1211 fdelete-dead-exceptions
1212 Common Report Var(flag_delete_dead_exceptions) Init(0) Optimization
1213 Delete dead instructions that may throw exceptions.
1215 fdelete-null-pointer-checks
1216 Common Report Var(flag_delete_null_pointer_checks) Init(-1) Optimization
1217 Delete useless null pointer checks.
1219 fdevirtualize-at-ltrans
1220 Common Report Var(flag_ltrans_devirtualize)
1221 Stream extra data to support more aggressive devirtualization in LTO local transformation mode.
1223 fdevirtualize-speculatively
1224 Common Report Var(flag_devirtualize_speculatively) Optimization
1225 Perform speculative devirtualization.
1227 fdevirtualize
1228 Common Report Var(flag_devirtualize) Optimization
1229 Try to convert virtual calls to direct ones.
1231 fdiagnostics-show-location=
1232 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1233 -fdiagnostics-show-location=[once|every-line]   How often to emit source location at the beginning of line-wrapped diagnostics.
1235 ; Required for these enum values.
1236 SourceInclude
1237 pretty-print.h
1239 Enum
1240 Name(diagnostic_prefixing_rule) Type(int)
1242 EnumValue
1243 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1245 EnumValue
1246 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1248 fdiagnostics-show-caret
1249 Common Var(flag_diagnostics_show_caret) Init(1)
1250 Show the source line with a caret indicating the column.
1252 fdiagnostics-show-labels
1253 Common Var(flag_diagnostics_show_labels) Init(1)
1254 Show labels annotating ranges of source code when showing source.
1256 fdiagnostics-show-line-numbers
1257 Common Var(flag_diagnostics_show_line_numbers) Init(1)
1258 Show line numbers in the left margin when showing source.
1260 fdiagnostics-color
1261 Common Alias(fdiagnostics-color=,always,never)
1264 fdiagnostics-color=
1265 Driver Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1266 -fdiagnostics-color=[never|always|auto] Colorize diagnostics.
1268 ; Required for these enum values.
1269 SourceInclude
1270 diagnostic-color.h
1272 Enum
1273 Name(diagnostic_color_rule) Type(int)
1275 EnumValue
1276 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1278 EnumValue
1279 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1281 EnumValue
1282 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1284 fdiagnostics-urls=
1285 Driver Common Joined RejectNegative Var(flag_diagnostics_show_urls) Enum(diagnostic_url_rule) Init(DIAGNOSTICS_URL_AUTO)
1286 -fdiagnostics-urls=[never|always|auto]  Embed URLs in diagnostics.
1288 ; Required for these enum values.
1289 SourceInclude
1290 diagnostic-url.h
1292 Enum
1293 Name(diagnostic_url_rule) Type(int)
1295 EnumValue
1296 Enum(diagnostic_url_rule) String(never) Value(DIAGNOSTICS_URL_NO)
1298 EnumValue
1299 Enum(diagnostic_url_rule) String(always) Value(DIAGNOSTICS_URL_YES)
1301 EnumValue
1302 Enum(diagnostic_url_rule) String(auto) Value(DIAGNOSTICS_URL_AUTO)
1304 fdiagnostics-format=
1305 Common Joined RejectNegative Enum(diagnostics_output_format)
1306 -fdiagnostics-format=[text|json] Select output format.
1308 ; Required for these enum values.
1309 SourceInclude
1310 diagnostic.h
1312 Enum
1313 Name(diagnostics_output_format) Type(int)
1315 EnumValue
1316 Enum(diagnostics_output_format) String(text) Value(DIAGNOSTICS_OUTPUT_FORMAT_TEXT)
1318 EnumValue
1319 Enum(diagnostics_output_format) String(json) Value(DIAGNOSTICS_OUTPUT_FORMAT_JSON)
1321 fdiagnostics-parseable-fixits
1322 Common Var(flag_diagnostics_parseable_fixits)
1323 Print fix-it hints in machine-readable form.
1325 fdiagnostics-generate-patch
1326 Common Var(flag_diagnostics_generate_patch)
1327 Print fix-it hints to stderr in unified diff format.
1329 fdiagnostics-show-option
1330 Common Var(flag_diagnostics_show_option) Init(1)
1331 Amend appropriate diagnostic messages with the command line option that controls them.
1333 fdiagnostics-minimum-margin-width=
1334 Common Joined UInteger Var(diagnostics_minimum_margin_width) Init(6)
1335 Set minimum width of left margin of source code when showing source.
1337 fdisable-
1338 Common Joined RejectNegative Var(common_deferred_options) Defer
1339 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass.
1341 fenable-
1342 Common Joined RejectNegative Var(common_deferred_options) Defer
1343 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass.
1345 fdump-
1346 Common Joined RejectNegative Var(common_deferred_options) Defer
1347 -fdump-<type>   Dump various compiler internals to a file.
1349 fdump-final-insns
1350 Driver RejectNegative
1352 fdump-final-insns=
1353 Common RejectNegative Joined Var(flag_dump_final_insns)
1354 -fdump-final-insns=filename     Dump to filename the insns at the end of translation.
1356 fdump-go-spec=
1357 Common RejectNegative Joined Var(flag_dump_go_spec)
1358 -fdump-go-spec=filename Write all declarations to file as Go code.
1360 fdump-noaddr
1361 Common Report Var(flag_dump_noaddr)
1362 Suppress output of addresses in debugging dumps.
1364 freport-bug
1365 Common Driver Var(flag_report_bug)
1366 Collect and dump debug information into temporary file if ICE in C/C++
1367 compiler occurred.
1369 fdump-internal-locations
1370 Common Var(flag_dump_locations) Init(0)
1371 Dump detailed information on GCC's internal representation of source code locations.
1373 fdump-passes
1374 Common Var(flag_dump_passes) Init(0)
1375 Dump optimization passes.
1377 fdump-unnumbered
1378 Common Report Var(flag_dump_unnumbered)
1379 Suppress output of instruction numbers, line number notes and addresses in debugging dumps.
1381 fdump-unnumbered-links
1382 Common Report Var(flag_dump_unnumbered_links)
1383 Suppress output of previous and next insn numbers in debugging dumps.
1385 fdwarf2-cfi-asm
1386 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1387 Enable CFI tables via GAS assembler directives.
1389 fearly-inlining
1390 Common Report Var(flag_early_inlining) Init(1) Optimization
1391 Perform early inlining.
1393 feliminate-dwarf2-dups
1394 Common Ignore
1395 Does nothing.  Preserved for backward compatibility.
1397 fipa-sra
1398 Common Report Var(flag_ipa_sra) Init(0) Optimization
1399 Perform interprocedural reduction of aggregates.
1401 feliminate-unused-debug-symbols
1402 Common Report Var(flag_debug_only_used_symbols) Init(1)
1403 Perform unused symbol elimination in debug info.
1405 feliminate-unused-debug-types
1406 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1407 Perform unused type elimination in debug info.
1409 femit-class-debug-always
1410 Common Report Var(flag_emit_class_debug_always) Init(0)
1411 Do not suppress C++ class debug information.
1413 fexceptions
1414 Common Report Var(flag_exceptions) Optimization
1415 Enable exception handling.
1417 fexpensive-optimizations
1418 Common Report Var(flag_expensive_optimizations) Optimization
1419 Perform a number of minor, expensive optimizations.
1421 fexcess-precision=
1422 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision) Init(EXCESS_PRECISION_DEFAULT) Optimization SetByCombined
1423 -fexcess-precision=[fast|standard]      Specify handling of excess floating-point precision.
1425 Enum
1426 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1428 EnumValue
1429 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1431 EnumValue
1432 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1434 ; Whether we permit the extended set of values for FLT_EVAL_METHOD
1435 ; introduced in ISO/IEC TS 18661-3, or limit ourselves to those in C99/C11.
1436 fpermitted-flt-eval-methods=
1437 Common Joined RejectNegative Enum(permitted_flt_eval_methods) Var(flag_permitted_flt_eval_methods) Init(PERMITTED_FLT_EVAL_METHODS_DEFAULT)
1438 -fpermitted-flt-eval-methods=[c11|ts-18661]     Specify which values of FLT_EVAL_METHOD are permitted.
1440 Enum
1441 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)
1443 EnumValue
1444 Enum(permitted_flt_eval_methods) String(c11) Value(PERMITTED_FLT_EVAL_METHODS_C11)
1446 EnumValue
1447 Enum(permitted_flt_eval_methods) String(ts-18661-3) Value(PERMITTED_FLT_EVAL_METHODS_TS_18661)
1449 ffast-math
1450 Common Optimization
1452 ffat-lto-objects
1453 Common Var(flag_fat_lto_objects)
1454 Output lto objects containing both the intermediate language and binary output.
1456 ffinite-math-only
1457 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1458 Assume no NaNs or infinities are generated.
1460 ffinite-loops
1461 Common Report Var(flag_finite_loops) Optimization
1462 Assume that loops with an exit will terminate and not loop indefinitely.
1464 ffixed-
1465 Common Joined RejectNegative Var(common_deferred_options) Defer
1466 -ffixed-<register>      Mark <register> as being unavailable to the compiler.
1468 ffloat-store
1469 Common Report Var(flag_float_store) Optimization
1470 Don't allocate floats and doubles in extended-precision registers.
1472 fforce-addr
1473 Common Ignore
1474 Does nothing.  Preserved for backward compatibility.
1476 fforward-propagate
1477 Common Report Var(flag_forward_propagate) Optimization
1478 Perform a forward propagation pass on RTL.
1480 ffp-contract=
1481 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST) Optimization
1482 -ffp-contract=[off|on|fast]     Perform floating-point expression contraction.
1484 Enum
1485 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1487 EnumValue
1488 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1490 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1491 EnumValue
1492 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1494 EnumValue
1495 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1497 ffp-int-builtin-inexact
1498 Common Report Var(flag_fp_int_builtin_inexact) Init(1) Optimization
1499 Allow built-in functions ceil, floor, round, trunc to raise \"inexact\" exceptions.
1501 ; Nonzero means don't put addresses of constant functions in registers.
1502 ; Used for compiling the Unix kernel, where strange substitutions are
1503 ; done on the assembly output.
1504 ffunction-cse
1505 Common Report Var(flag_no_function_cse,0) Optimization
1506 Allow function addresses to be held in registers.
1508 ffunction-sections
1509 Common Report Var(flag_function_sections)
1510 Place each function into its own section.
1512 fgcse
1513 Common Report Var(flag_gcse) Optimization
1514 Perform global common subexpression elimination.
1516 fgcse-lm
1517 Common Report Var(flag_gcse_lm) Init(1) Optimization
1518 Perform enhanced load motion during global common subexpression elimination.
1520 fgcse-sm
1521 Common Report Var(flag_gcse_sm) Init(0) Optimization
1522 Perform store motion after global common subexpression elimination.
1524 fgcse-las
1525 Common Report Var(flag_gcse_las) Init(0) Optimization
1526 Perform redundant load after store elimination in global common subexpression
1527 elimination.
1529 fgcse-after-reload
1530 Common Report Var(flag_gcse_after_reload) Optimization
1531 Perform global common subexpression elimination after register allocation has
1532 finished.
1534 Enum
1535 Name(dwarf_gnat_encodings) Type(int)
1537 EnumValue
1538 Enum(dwarf_gnat_encodings) String(all) Value(DWARF_GNAT_ENCODINGS_ALL)
1540 EnumValue
1541 Enum(dwarf_gnat_encodings) String(gdb) Value(DWARF_GNAT_ENCODINGS_GDB)
1543 EnumValue
1544 Enum(dwarf_gnat_encodings) String(minimal) Value(DWARF_GNAT_ENCODINGS_MINIMAL)
1546 fgnat-encodings=
1547 Common Enum(dwarf_gnat_encodings) Joined RejectNegative Report Undocumented Var(gnat_encodings)
1548 -fgnat-encodings=[all|gdb|minimal]      Select the balance between GNAT encodings and standard DWARF emitted in the debug information.
1550 ; This option is not documented yet as its semantics will change.
1551 fgraphite
1552 Common Report Var(flag_graphite) Optimization
1553 Enable in and out of Graphite representation.
1555 fgraphite-identity
1556 Common Report Var(flag_graphite_identity) Optimization
1557 Enable Graphite Identity transformation.
1559 fhoist-adjacent-loads
1560 Common Report Var(flag_hoist_adjacent_loads) Optimization
1561 Enable hoisting adjacent loads to encourage generating conditional move
1562 instructions.
1564 fkeep-gc-roots-live
1565 Common Undocumented Report Var(flag_keep_gc_roots_live) Optimization
1566 ; Always keep a pointer to a live memory block
1568 floop-parallelize-all
1569 Common Report Var(flag_loop_parallelize_all) Optimization
1570 Mark all loops as parallel.
1572 floop-strip-mine
1573 Common Alias(floop-nest-optimize)
1574 Enable loop nest transforms.  Same as -floop-nest-optimize.
1576 floop-interchange
1577 Common Report Var(flag_loop_interchange) Optimization
1578 Enable loop interchange on trees.
1580 floop-block
1581 Common Alias(floop-nest-optimize)
1582 Enable loop nest transforms.  Same as -floop-nest-optimize.
1584 floop-unroll-and-jam
1585 Common Report Var(flag_unroll_jam) Optimization
1586 Perform unroll-and-jam on loops.
1588 fgnu-tm
1589 Common Report Var(flag_tm)
1590 Enable support for GNU transactional memory.
1592 fgnu-unique
1593 Common Report Var(flag_gnu_unique) Init(1)
1594 Use STB_GNU_UNIQUE if supported by the assembler.
1596 floop-flatten
1597 Common Ignore
1598 Does nothing. Preserved for backward compatibility.
1600 floop-nest-optimize
1601 Common Report Var(flag_loop_nest_optimize) Optimization
1602 Enable the loop nest optimizer.
1604 fstrict-volatile-bitfields
1605 Common Report Var(flag_strict_volatile_bitfields) Init(-1) Optimization
1606 Force bitfield accesses to match their type width.
1608 fstore-merging
1609 Common Report Var(flag_store_merging) Optimization
1610 Merge adjacent stores.
1612 fguess-branch-probability
1613 Common Report Var(flag_guess_branch_prob) Optimization
1614 Enable guessing of branch probabilities.
1616 ; Nonzero means ignore `#ident' directives.  0 means handle them.
1617 ; Generate position-independent code for executables if possible
1618 ; On SVR4 targets, it also controls whether or not to emit a
1619 ; string identifying the compiler.
1620 fident
1621 Common Report Var(flag_no_ident,0)
1622 Process #ident directives.
1624 fif-conversion
1625 Common Report Var(flag_if_conversion) Optimization
1626 Perform conversion of conditional jumps to branchless equivalents.
1628 fif-conversion2
1629 Common Report Var(flag_if_conversion2) Optimization
1630 Perform conversion of conditional jumps to conditional execution.
1632 fstack-reuse=
1633 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL) Optimization
1634 -fstack-reuse=[all|named_vars|none]     Set stack reuse level for local variables.
1636 Enum
1637 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1639 EnumValue
1640 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1642 EnumValue
1643 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1645 EnumValue
1646 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1648 ftree-loop-if-convert
1649 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1650 Convert conditional jumps in innermost loops to branchless equivalents.
1652 ftree-loop-if-convert-stores
1653 Common Ignore
1654 Does nothing. Preserved for backward compatibility.
1656 ; -finhibit-size-directive inhibits output of .size for ELF.
1657 ; This is used only for compiling crtstuff.c,
1658 ; and it may be extended to other effects
1659 ; needed for crtstuff.c on other systems.
1660 finhibit-size-directive
1661 Common Report Var(flag_inhibit_size_directive)
1662 Do not generate .size directives.
1664 findirect-inlining
1665 Common Report Var(flag_indirect_inlining) Optimization
1666 Perform indirect inlining.
1668 ; General flag to enable inlining.  Specifying -fno-inline will disable
1669 ; all inlining apart from always-inline functions.
1670 finline
1671 Common Report Var(flag_no_inline,0) Init(0) Optimization
1672 Enable inlining of function declared \"inline\", disabling disables all inlining.
1674 finline-small-functions
1675 Common Report Var(flag_inline_small_functions) Optimization
1676 Integrate functions into their callers when code size is known not to grow.
1678 finline-functions
1679 Common Report Var(flag_inline_functions) Optimization
1680 Integrate functions not declared \"inline\" into their callers when profitable.
1682 finline-functions-called-once
1683 Common Report Var(flag_inline_functions_called_once) Optimization
1684 Integrate functions only required by their single caller.
1686 finline-limit-
1687 Common RejectNegative Joined Alias(finline-limit=)
1689 finline-limit=
1690 Common RejectNegative Joined UInteger
1691 -finline-limit=<number> Limit the size of inlined functions to <number>.
1693 finline-atomics
1694 Common Report Var(flag_inline_atomics) Init(1) Optimization
1695 Inline __atomic operations when a lock free instruction sequence is available.
1697 fcf-protection
1698 Common RejectNegative Alias(fcf-protection=,full)
1700 fcf-protection=
1701 Common Report Joined RejectNegative Enum(cf_protection_level) Var(flag_cf_protection) Init(CF_NONE)
1702 -fcf-protection=[full|branch|return|none]       Instrument functions with checks to verify jump/call/return control-flow transfer
1703 instructions have valid targets.
1705 Enum
1706 Name(cf_protection_level) Type(enum cf_protection_level) UnknownError(unknown Control-Flow Protection Level %qs)
1708 EnumValue
1709 Enum(cf_protection_level) String(full) Value(CF_FULL)
1711 EnumValue
1712 Enum(cf_protection_level) String(branch) Value(CF_BRANCH)
1714 EnumValue
1715 Enum(cf_protection_level) String(return) Value(CF_RETURN)
1717 EnumValue
1718 Enum(cf_protection_level) String(none) Value(CF_NONE)
1720 finstrument-functions
1721 Common Report Var(flag_instrument_function_entry_exit)
1722 Instrument function entry and exit with profiling calls.
1724 finstrument-functions-exclude-function-list=
1725 Common RejectNegative Joined
1726 -finstrument-functions-exclude-function-list=name,...  Do not instrument listed functions.
1728 finstrument-functions-exclude-file-list=
1729 Common RejectNegative Joined
1730 -finstrument-functions-exclude-file-list=filename,...  Do not instrument functions listed in files.
1732 fipa-cp
1733 Common Report Var(flag_ipa_cp) Optimization
1734 Perform interprocedural constant propagation.
1736 fipa-cp-clone
1737 Common Report Var(flag_ipa_cp_clone) Optimization
1738 Perform cloning to make Interprocedural constant propagation stronger.
1740 fipa-cp-alignment
1741 Common Ignore
1742 Does nothing.  Preserved for backward compatibility.
1744 fipa-bit-cp
1745 Common Report Var(flag_ipa_bit_cp) Optimization
1746 Perform interprocedural bitwise constant propagation.
1748 fipa-profile
1749 Common Report Var(flag_ipa_profile) Init(0) Optimization
1750 Perform interprocedural profile propagation.
1752 fipa-pta
1753 Common Report Var(flag_ipa_pta) Init(0) Optimization
1754 Perform interprocedural points-to analysis.
1756 fipa-pure-const
1757 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1758 Discover pure and const functions.
1760 fipa-icf
1761 Common Report Var(flag_ipa_icf) Optimization
1762 Perform Identical Code Folding for functions and read-only variables.
1764 fipa-icf-functions
1765 Common Report Var(flag_ipa_icf_functions) Optimization
1766 Perform Identical Code Folding for functions.
1768 fipa-icf-variables
1769 Common Report Var(flag_ipa_icf_variables) Optimization
1770 Perform Identical Code Folding for variables.
1772 fipa-reference
1773 Common Report Var(flag_ipa_reference) Init(0) Optimization
1774 Discover read-only and non addressable static variables.
1776 fipa-reference-addressable
1777 Common Report Var(flag_ipa_reference_addressable) Init(0) Optimization
1778 Discover read-only, write-only and non-addressable static variables.
1780 fipa-stack-alignment
1781 Common Report Var(flag_ipa_stack_alignment) Init(1) Optimization
1782 Reduce stack alignment on call sites if possible.
1784 fipa-matrix-reorg
1785 Common Ignore
1786 Does nothing. Preserved for backward compatibility.
1788 fipa-struct-reorg
1789 Common Ignore
1790 Does nothing. Preserved for backward compatibility.
1792 fipa-vrp
1793 Common Report Var(flag_ipa_vrp) Optimization
1794 Perform IPA Value Range Propagation.
1796 fira-algorithm=
1797 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB) Optimization
1798 -fira-algorithm=[CB|priority]   Set the used IRA algorithm.
1800 Enum
1801 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1803 EnumValue
1804 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1806 EnumValue
1807 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1809 fira-region=
1810 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT) Optimization
1811 -fira-region=[one|all|mixed]    Set regions for IRA.
1813 Enum
1814 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1816 EnumValue
1817 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1819 EnumValue
1820 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1822 EnumValue
1823 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1825 fira-hoist-pressure
1826 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1827 Use IRA based register pressure calculation
1828 in RTL hoist optimizations.
1830 fira-loop-pressure
1831 Common Report Var(flag_ira_loop_pressure) Optimization
1832 Use IRA based register pressure calculation
1833 in RTL loop optimizations.
1835 fira-share-save-slots
1836 Common Report Var(flag_ira_share_save_slots) Init(1) Optimization
1837 Share slots for saving different hard registers.
1839 fira-share-spill-slots
1840 Common Report Var(flag_ira_share_spill_slots) Init(1) Optimization
1841 Share stack slots for spilled pseudo-registers.
1843 fira-verbose=
1844 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1845 -fira-verbose=<number>  Control IRA's level of diagnostic messages.
1847 fivopts
1848 Common Report Var(flag_ivopts) Init(1) Optimization
1849 Optimize induction variables on trees.
1851 fjump-tables
1852 Common Var(flag_jump_tables) Init(1) Optimization
1853 Use jump tables for sufficiently large switch statements.
1855 fkeep-inline-functions
1856 Common Report Var(flag_keep_inline_functions)
1857 Generate code for functions even if they are fully inlined.
1859 fkeep-static-functions
1860 Common Report Var(flag_keep_static_functions)
1861 Generate code for static functions even if they are never called.
1863 fkeep-static-consts
1864 Common Report Var(flag_keep_static_consts) Init(1)
1865 Emit static const variables even if they are not used.
1867 fleading-underscore
1868 Common Report Var(flag_leading_underscore) Init(-1)
1869 Give external symbols a leading underscore.
1871 floop-optimize
1872 Common Ignore
1873 Does nothing.  Preserved for backward compatibility.
1875 flra-remat
1876 Common Report Var(flag_lra_remat) Optimization
1877 Do CFG-sensitive rematerialization in LRA.
1879 flto
1880 Common
1881 Enable link-time optimization.
1883 flto=
1884 Common RejectNegative Joined Var(flag_lto)
1885 Link-time optimization with number of parallel jobs or jobserver.
1887 Enum
1888 Name(lto_partition_model) Type(enum lto_partition_model) UnknownError(unknown LTO partitioning model %qs)
1890 EnumValue
1891 Enum(lto_partition_model) String(none) Value(LTO_PARTITION_NONE)
1893 EnumValue
1894 Enum(lto_partition_model) String(one) Value(LTO_PARTITION_ONE)
1896 EnumValue
1897 Enum(lto_partition_model) String(balanced) Value(LTO_PARTITION_BALANCED)
1899 EnumValue
1900 Enum(lto_partition_model) String(1to1) Value(LTO_PARTITION_1TO1)
1902 EnumValue
1903 Enum(lto_partition_model) String(max) Value(LTO_PARTITION_MAX)
1905 flto-partition=
1906 Common Joined RejectNegative Enum(lto_partition_model) Var(flag_lto_partition) Init(LTO_PARTITION_BALANCED)
1907 Specify the algorithm to partition symbols and vars at linktime.
1909 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1910 flto-compression-level=
1911 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1) IntegerRange(0, 19)
1912 -flto-compression-level=<number>        Use zlib/zstd compression level <number> for IL.
1914 flto-odr-type-merging
1915 Common Ignore
1916 Does nothing.  Preserved for backward compatibility.
1918 flto-report
1919 Common Report Var(flag_lto_report) Init(0)
1920 Report various link-time optimization statistics.
1922 flto-report-wpa
1923 Common Report Var(flag_lto_report_wpa) Init(0)
1924 Report various link-time optimization statistics for WPA only.
1926 fmath-errno
1927 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1928 Set errno after built-in math functions.
1930 fmax-errors=
1931 Common Joined RejectNegative UInteger Var(flag_max_errors)
1932 -fmax-errors=<number>   Maximum number of errors to report.
1934 fmem-report
1935 Common Report Var(mem_report)
1936 Report on permanent memory allocation.
1938 fmem-report-wpa
1939 Common Report Var(mem_report_wpa)
1940 Report on permanent memory allocation in WPA only.
1942 ; This will attempt to merge constant section constants, if 1 only
1943 ; string constants and constants from constant pool, if 2 also constant
1944 ; variables.
1945 fmerge-all-constants
1946 Common Report Var(flag_merge_constants,2) Init(1)
1947 Attempt to merge identical constants and constant variables.
1949 fmerge-constants
1950 Common Report Var(flag_merge_constants,1)
1951 Attempt to merge identical constants across compilation units.
1953 fmerge-debug-strings
1954 Common Report Var(flag_merge_debug_strings) Init(1)
1955 Attempt to merge identical debug strings across compilation units.
1957 fmessage-length=
1958 Common RejectNegative Joined UInteger
1959 -fmessage-length=<number>       Limit diagnostics to <number> characters per line.  0 suppresses line-wrapping.
1961 fmodulo-sched
1962 Common Report Var(flag_modulo_sched) Optimization
1963 Perform SMS based modulo scheduling before the first scheduling pass.
1965 fmodulo-sched-allow-regmoves
1966 Common Report Var(flag_modulo_sched_allow_regmoves) Optimization
1967 Perform SMS based modulo scheduling with register moves allowed.
1969 fmove-loop-invariants
1970 Common Report Var(flag_move_loop_invariants) Optimization
1971 Move loop invariant computations out of loops.
1973 fdce
1974 Common Var(flag_dce) Init(1) Optimization
1975 Use the RTL dead code elimination pass.
1977 fdse
1978 Common Var(flag_dse) Init(0) Optimization
1979 Use the RTL dead store elimination pass.
1981 freschedule-modulo-scheduled-loops
1982 Common Report Var(flag_resched_modulo_sched) Optimization
1983 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling.
1985 fnon-call-exceptions
1986 Common Report Var(flag_non_call_exceptions) Optimization
1987 Support synchronous non-call exceptions.
1989 foffload=
1990 Common Driver Joined MissingArgError(options or targets missing after %qs)
1991 -foffload=<targets>=<options>  Specify offloading targets and options for them.
1993 foffload-abi=
1994 Common Joined RejectNegative Enum(offload_abi) Var(flag_offload_abi) Init(OFFLOAD_ABI_UNSET)
1995 -foffload-abi=[lp64|ilp32]     Set the ABI to use in an offload compiler.
1997 Enum
1998 Name(offload_abi) Type(enum offload_abi) UnknownError(unknown offload ABI %qs)
2000 EnumValue
2001 Enum(offload_abi) String(ilp32) Value(OFFLOAD_ABI_ILP32)
2003 EnumValue
2004 Enum(offload_abi) String(lp64) Value(OFFLOAD_ABI_LP64)
2006 fomit-frame-pointer
2007 Common Report Var(flag_omit_frame_pointer) Optimization
2008 When possible do not generate stack frames.
2010 fopt-info
2011 Common Report Var(flag_opt_info) Optimization
2012 Enable all optimization info dumps on stderr.
2014 fopt-info-
2015 Common Joined RejectNegative Var(common_deferred_options) Defer
2016 -fopt-info[-<type>=filename]    Dump compiler optimization details.
2018 fsave-optimization-record
2019 Common Report Var(flag_save_optimization_record) Optimization
2020 Write a SRCFILE.opt-record.json file detailing what optimizations were performed.
2022 foptimize-register-move
2023 Common Ignore
2024 Does nothing. Preserved for backward compatibility.
2026 foptimize-sibling-calls
2027 Common Report Var(flag_optimize_sibling_calls) Optimization
2028 Optimize sibling and tail recursive calls.
2030 fpartial-inlining
2031 Common Report Var(flag_partial_inlining) Optimization
2032 Perform partial inlining.
2034 fpre-ipa-mem-report
2035 Common Report Var(pre_ipa_mem_report)
2036 Report on memory allocation before interprocedural optimization.
2038 fpost-ipa-mem-report
2039 Common Report Var(post_ipa_mem_report)
2040 Report on memory allocation before interprocedural optimization.
2042 fpack-struct
2043 Common Report Var(flag_pack_struct) Optimization
2044 Pack structure members together without holes.
2046 fpack-struct=
2047 Common RejectNegative Joined UInteger Optimization
2048 -fpack-struct=<number>  Set initial maximum structure member alignment.
2050 fpcc-struct-return
2051 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
2052 Return small aggregates in memory, not registers.
2054 fpeel-loops
2055 Common Report Var(flag_peel_loops) Optimization
2056 Perform loop peeling.
2058 fpeephole
2059 Common Report Var(flag_no_peephole,0) Optimization
2060 Enable machine specific peephole optimizations.
2062 fpeephole2
2063 Common Report Var(flag_peephole2) Optimization
2064 Enable an RTL peephole pass before sched2.
2066 fPIC
2067 Common Report Var(flag_pic,2) Negative(fPIE) Init(-1)
2068 Generate position-independent code if possible (large mode).
2070 fPIE
2071 Common Report Var(flag_pie,2) Negative(fpic) Init(-1)
2072 Generate position-independent code for executables if possible (large mode).
2074 fpic
2075 Common Report Var(flag_pic,1) Negative(fpie) Init(-1)
2076 Generate position-independent code if possible (small mode).
2078 fpie
2079 Common Report Var(flag_pie,1) Negative(fPIC) Init(-1)
2080 Generate position-independent code for executables if possible (small mode).
2082 fplt
2083 Common Report Var(flag_plt) Init(1) Optimization
2084 Use PLT for PIC calls (-fno-plt: load the address from GOT at call site).
2086 fplugin=
2087 Common Joined RejectNegative Var(common_deferred_options) Defer
2088 Specify a plugin to load.
2090 fplugin-arg-
2091 Common Joined RejectNegative Var(common_deferred_options) Defer
2092 -fplugin-arg-<name>-<key>[=<value>]     Specify argument <key>=<value> for plugin <name>.
2094 fpredictive-commoning
2095 Common Report Var(flag_predictive_commoning) Optimization
2096 Run predictive commoning optimization.
2098 fprefetch-loop-arrays
2099 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
2100 Generate prefetch instructions, if available, for arrays in loops.
2102 fprofile
2103 Common Report Var(profile_flag)
2104 Enable basic program profiling code.
2106 fprofile-abs-path
2107 Common Report Var(profile_abs_path_flag)
2108 Generate absolute source path names for gcov.
2110 fprofile-arcs
2111 Common Report Var(profile_arc_flag)
2112 Insert arc-based program profiling code.
2114 fprofile-dir=
2115 Common Joined RejectNegative Var(profile_data_prefix)
2116 Set the top-level directory for storing the profile data.
2117 The default is 'pwd'.
2119 fprofile-note=
2120 Common Joined RejectNegative Var(profile_note_location)
2121 Select the name for storing the profile note file.
2123 fprofile-correction
2124 Common Report Var(flag_profile_correction)
2125 Enable correction of flow inconsistent profile data input.
2127 fprofile-update=
2128 Common Joined RejectNegative Enum(profile_update) Var(flag_profile_update) Init(PROFILE_UPDATE_SINGLE)
2129 -fprofile-update=[single|atomic|prefer-atomic]  Set the profile update method.
2131 fprofile-filter-files=
2132 Common Joined RejectNegative Var(flag_profile_filter_files)
2133 Instrument only functions from files where names match any regular expression (separated by a semi-colon).
2135 fprofile-exclude-files=
2136 Common Joined RejectNegative Var(flag_profile_exclude_files)
2137 Instrument only functions from files where names do not match all the regular expressions (separated by a semi-colon).
2139 Enum
2140 Name(profile_update) Type(enum profile_update) UnknownError(unknown profile update method %qs)
2142 EnumValue
2143 Enum(profile_update) String(single) Value(PROFILE_UPDATE_SINGLE)
2145 EnumValue
2146 Enum(profile_update) String(atomic) Value(PROFILE_UPDATE_ATOMIC)
2148 EnumValue
2149 Enum(profile_update) String(prefer-atomic) Value(PROFILE_UPDATE_PREFER_ATOMIC)
2151 fprofile-generate
2152 Common
2153 Enable common options for generating profile info for profile feedback directed optimizations.
2155 fprofile-generate=
2156 Common Joined RejectNegative
2157 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=.
2159 fprofile-use
2160 Common Var(flag_profile_use)
2161 Enable common options for performing profile feedback directed optimizations.
2163 fprofile-use=
2164 Common Joined RejectNegative
2165 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=.
2167 fprofile-values
2168 Common Report Var(flag_profile_values)
2169 Insert code to profile values of expressions.
2171 fprofile-report
2172 Common Report Var(profile_report)
2173 Report on consistency of profile.
2175 fprofile-reorder-functions
2176 Common Report Var(flag_profile_reorder_functions)
2177 Enable function reordering that improves code placement.
2179 fpatchable-function-entry=
2180 Common Joined Optimization
2181 Insert NOP instructions at each function entry.
2183 frandom-seed
2184 Common Var(common_deferred_options) Defer
2186 frandom-seed=
2187 Common Joined RejectNegative Var(common_deferred_options) Defer
2188 -frandom-seed=<string>  Make compile reproducible using <string>.
2190 ; This switch causes the command line that was used to create an
2191 ; object file to be recorded into the object file.  The exact format
2192 ; of this recording is target and binary file format dependent.
2193 ; It is related to the -fverbose-asm switch, but that switch only
2194 ; records information in the assembler output file as comments, so
2195 ; they never reach the object file.
2196 frecord-gcc-switches
2197 Common Report Var(flag_record_gcc_switches)
2198 Record gcc command line switches in the object file.
2200 freg-struct-return
2201 Common Report Var(flag_pcc_struct_return,0) Optimization
2202 Return small aggregates in registers.
2204 fregmove
2205 Common Ignore
2206 Does nothing. Preserved for backward compatibility.
2208 flifetime-dse
2209 Common Report Var(flag_lifetime_dse,2) Init(2) Optimization
2210 Tell DSE that the storage for a C++ object is dead when the constructor
2211 starts and when the destructor finishes.
2213 flifetime-dse=
2214 Common Joined RejectNegative UInteger Var(flag_lifetime_dse) Optimization IntegerRange(0, 2)
2216 flive-patching
2217 Common RejectNegative Alias(flive-patching=,inline-clone) Optimization
2219 flive-patching=
2220 Common Report Joined RejectNegative Enum(live_patching_level) Var(flag_live_patching) Init(LIVE_PATCHING_NONE) Optimization
2221 -flive-patching=[inline-only-static|inline-clone]       Control IPA
2222 optimizations to provide a safe compilation for live-patching.  At the same
2223 time, provides multiple-level control on the enabled IPA optimizations.
2225 Enum
2226 Name(live_patching_level) Type(enum live_patching_level) UnknownError(unknown Live-Patching Level %qs)
2228 EnumValue
2229 Enum(live_patching_level) String(inline-only-static) Value(LIVE_PATCHING_INLINE_ONLY_STATIC)
2231 EnumValue
2232 Enum(live_patching_level) String(inline-clone) Value(LIVE_PATCHING_INLINE_CLONE)
2234 fallocation-dce
2235 Common Report Var(flag_allocation_dce) Init(1) Optimization
2236 Tell DCE to remove unused C++ allocations.
2238 flive-range-shrinkage
2239 Common Report Var(flag_live_range_shrinkage) Init(0) Optimization
2240 Relief of register pressure through live range shrinkage.
2242 frename-registers
2243 Common Report Var(flag_rename_registers) Init(2) Optimization
2244 Perform a register renaming optimization pass.
2246 fschedule-fusion
2247 Common Report Var(flag_schedule_fusion) Init(2) Optimization
2248 Perform a target dependent instruction fusion optimization pass.
2250 freorder-blocks
2251 Common Report Var(flag_reorder_blocks) Optimization
2252 Reorder basic blocks to improve code placement.
2254 freorder-blocks-algorithm=
2255 Common Joined RejectNegative Enum(reorder_blocks_algorithm) Var(flag_reorder_blocks_algorithm) Init(REORDER_BLOCKS_ALGORITHM_SIMPLE) Optimization
2256 -freorder-blocks-algorithm=[simple|stc] Set the used basic block reordering algorithm.
2258 Enum
2259 Name(reorder_blocks_algorithm) Type(enum reorder_blocks_algorithm) UnknownError(unknown basic block reordering algorithm %qs)
2261 EnumValue
2262 Enum(reorder_blocks_algorithm) String(simple) Value(REORDER_BLOCKS_ALGORITHM_SIMPLE)
2264 EnumValue
2265 Enum(reorder_blocks_algorithm) String(stc) Value(REORDER_BLOCKS_ALGORITHM_STC)
2267 freorder-blocks-and-partition
2268 Common Report Var(flag_reorder_blocks_and_partition) Optimization
2269 Reorder basic blocks and partition into hot and cold sections.
2271 freorder-functions
2272 Common Report Var(flag_reorder_functions) Optimization
2273 Reorder functions to improve code placement.
2275 frerun-cse-after-loop
2276 Common Report Var(flag_rerun_cse_after_loop) Optimization
2277 Add a common subexpression elimination pass after loop optimizations.
2279 frerun-loop-opt
2280 Common Ignore
2281 Does nothing.  Preserved for backward compatibility.
2283 frounding-math
2284 Common Report Var(flag_rounding_math) Optimization SetByCombined
2285 Disable optimizations that assume default FP rounding behavior.
2287 fsched-interblock
2288 Common Report Var(flag_schedule_interblock) Init(1) Optimization
2289 Enable scheduling across basic blocks.
2291 fsched-pressure
2292 Common Report Var(flag_sched_pressure) Init(0) Optimization
2293 Enable register pressure sensitive insn scheduling.
2295 fsched-spec
2296 Common Report Var(flag_schedule_speculative) Init(1) Optimization
2297 Allow speculative motion of non-loads.
2299 fsched-spec-load
2300 Common Report Var(flag_schedule_speculative_load) Optimization
2301 Allow speculative motion of some loads.
2303 fsched-spec-load-dangerous
2304 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
2305 Allow speculative motion of more loads.
2307 fsched-verbose=
2308 Common RejectNegative Joined UInteger Var(sched_verbose_param) Init(1)
2309 -fsched-verbose=<number>        Set the verbosity level of the scheduler.
2311 fsched2-use-superblocks
2312 Common Report Var(flag_sched2_use_superblocks) Optimization
2313 If scheduling post reload, do superblock scheduling.
2315 fsched2-use-traces
2316 Common Ignore
2317 Does nothing.  Preserved for backward compatibility.
2319 fschedule-insns
2320 Common Report Var(flag_schedule_insns) Optimization
2321 Reschedule instructions before register allocation.
2323 fschedule-insns2
2324 Common Report Var(flag_schedule_insns_after_reload) Optimization
2325 Reschedule instructions after register allocation.
2327 ; This flag should be on when a target implements non-trivial
2328 ; scheduling hooks, maybe saving some information for its own sake.
2329 ; On IA64, for example, this is used for correct bundling.
2330 fselective-scheduling
2331 Common Report Var(flag_selective_scheduling) Optimization
2332 Schedule instructions using selective scheduling algorithm.
2334 fselective-scheduling2
2335 Common Report Var(flag_selective_scheduling2) Optimization
2336 Run selective scheduling after reload.
2338 fself-test=
2339 Common Undocumented Joined Var(flag_self_test)
2340 Run self-tests, using the given path to locate test files.
2342 fsel-sched-pipelining
2343 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
2344 Perform software pipelining of inner loops during selective scheduling.
2346 fsel-sched-pipelining-outer-loops
2347 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
2348 Perform software pipelining of outer loops during selective scheduling.
2350 fsel-sched-reschedule-pipelined
2351 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
2352 Reschedule pipelined regions without pipelining.
2354 fsemantic-interposition
2355 Common Report Var(flag_semantic_interposition) Init(1)
2356 Allow interposing function (or variables) by ones with different semantics (or initializer) respectively by dynamic linker.
2358 ; sched_stalled_insns means that insns can be moved prematurely from the queue
2359 ; of stalled insns into the ready list.
2360 fsched-stalled-insns
2361 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
2362 Allow premature scheduling of queued insns.
2364 fsched-stalled-insns=
2365 Common RejectNegative Joined UInteger Optimization
2366 -fsched-stalled-insns=<number>  Set number of queued insns that can be prematurely scheduled.
2368 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
2369 ; be examined for a dependency on a stalled insn that is candidate for
2370 ; premature removal from the queue of stalled insns into the ready list (has
2371 ; an effect only if the flag 'sched_stalled_insns' is set).
2372 fsched-stalled-insns-dep
2373 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
2374 Set dependence distance checking in premature scheduling of queued insns.
2376 fsched-stalled-insns-dep=
2377 Common RejectNegative Joined UInteger Optimization
2378 -fsched-stalled-insns-dep=<number>      Set dependence distance checking in premature scheduling of queued insns.
2380 fsched-group-heuristic
2381 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
2382 Enable the group heuristic in the scheduler.
2384 fsched-critical-path-heuristic
2385 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
2386 Enable the critical path heuristic in the scheduler.
2388 fsched-spec-insn-heuristic
2389 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
2390 Enable the speculative instruction heuristic in the scheduler.
2392 fsched-rank-heuristic
2393 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
2394 Enable the rank heuristic in the scheduler.
2396 fsched-last-insn-heuristic
2397 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
2398 Enable the last instruction heuristic in the scheduler.
2400 fsched-dep-count-heuristic
2401 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
2402 Enable the dependent count heuristic in the scheduler.
2404 fsection-anchors
2405 Common Report Var(flag_section_anchors) Optimization
2406 Access data in the same section from shared anchor points.
2408 fsee
2409 Common Ignore
2410 Does nothing.  Preserved for backward compatibility.
2412 fzee
2413 Common Ignore
2414 Does nothing.  Preserved for backward compatibility.
2416 free
2417 Common Report Var(flag_ree) Init(0)
2418 Turn on Redundant Extensions Elimination pass.
2420 fshow-column
2421 Common Report Var(flag_show_column) Init(1)
2422 Show column numbers in diagnostics, when available.  Default on.
2424 fshrink-wrap
2425 Common Report Var(flag_shrink_wrap) Optimization
2426 Emit function prologues only before parts of the function that need it,
2427 rather than at the top of the function.
2429 fshrink-wrap-separate
2430 Common Report Var(flag_shrink_wrap_separate) Init(1) Optimization
2431 Shrink-wrap parts of the prologue and epilogue separately.
2433 fsignaling-nans
2434 Common Report Var(flag_signaling_nans) Optimization SetByCombined
2435 Disable optimizations observable by IEEE signaling NaNs.
2437 fsigned-zeros
2438 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
2439 Disable floating point optimizations that ignore the IEEE signedness of zero.
2441 fsingle-precision-constant
2442 Common Report Var(flag_single_precision_constant) Optimization
2443 Convert floating point constants to single precision constants.
2445 fsplit-ivs-in-unroller
2446 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
2447 Split lifetimes of induction variables when loops are unrolled.
2449 fsplit-stack
2450 Common Report Var(flag_split_stack) Init(-1)
2451 Generate discontiguous stack frames.
2453 fsplit-wide-types
2454 Common Report Var(flag_split_wide_types) Optimization
2455 Split wide types into independent registers.
2457 fsplit-wide-types-early
2458 Common Report Var(flag_split_wide_types_early) Optimization
2459 Split wide types into independent registers earlier.
2461 fssa-backprop
2462 Common Report Var(flag_ssa_backprop) Init(1) Optimization
2463 Enable backward propagation of use properties at the SSA level.
2465 fssa-phiopt
2466 Common Report Var(flag_ssa_phiopt) Optimization
2467 Optimize conditional patterns using SSA PHI nodes.
2469 fstdarg-opt
2470 Common Report Var(flag_stdarg_opt) Init(1) Optimization
2471 Optimize amount of stdarg registers saved to stack at start of function.
2473 fvariable-expansion-in-unroller
2474 Common Report Var(flag_variable_expansion_in_unroller) Optimization
2475 Apply variable expansion when loops are unrolled.
2477 fstack-check=
2478 Common Report RejectNegative Joined Optimization
2479 -fstack-check=[no|generic|specific]     Insert stack checking code into the program.
2481 fstack-check
2482 Common Alias(fstack-check=, specific, no)
2483 Insert stack checking code into the program.  Same as -fstack-check=specific.
2485 fstack-clash-protection
2486 Common Report Var(flag_stack_clash_protection) Optimization
2487 Insert code to probe each page of stack space as it is allocated to protect
2488 from stack-clash style attacks.
2490 fstack-limit
2491 Common Var(common_deferred_options) Defer
2493 fstack-limit-register=
2494 Common RejectNegative Joined Var(common_deferred_options) Defer
2495 -fstack-limit-register=<register>       Trap if the stack goes past <register>.
2497 fstack-limit-symbol=
2498 Common RejectNegative Joined Var(common_deferred_options) Defer
2499 -fstack-limit-symbol=<name>     Trap if the stack goes past symbol <name>.
2501 fstack-protector
2502 Common Report Var(flag_stack_protect, 1) Init(-1) Optimization
2503 Use propolice as a stack protection method.
2505 fstack-protector-all
2506 Common Report RejectNegative Var(flag_stack_protect, 2) Init(-1) Optimization
2507 Use a stack protection method for every function.
2509 fstack-protector-strong
2510 Common Report RejectNegative Var(flag_stack_protect, 3) Init(-1) Optimization
2511 Use a smart stack protection method for certain functions.
2513 fstack-protector-explicit
2514 Common Report RejectNegative Var(flag_stack_protect, 4) Optimization
2515 Use stack protection method only for functions with the stack_protect attribute.
2517 fstack-usage
2518 Common RejectNegative Var(flag_stack_usage)
2519 Output stack usage information on a per-function basis.
2521 fstrength-reduce
2522 Common Ignore
2523 Does nothing.  Preserved for backward compatibility.
2525 ; Nonzero if we should do (language-dependent) alias analysis.
2526 ; Typically, this analysis will assume that expressions of certain
2527 ; types do not alias expressions of certain other types.  Only used
2528 ; if alias analysis (in general) is enabled.
2529 fstrict-aliasing
2530 Common Report Var(flag_strict_aliasing) Optimization
2531 Assume strict aliasing rules apply.
2533 fstrict-overflow
2534 Common Report
2535 Treat signed overflow as undefined.  Negated as -fwrapv -fwrapv-pointer.
2537 fsync-libcalls
2538 Common Report Var(flag_sync_libcalls) Init(1)
2539 Implement __atomic operations via libcalls to legacy __sync functions.
2541 fsyntax-only
2542 Common Report Var(flag_syntax_only)
2543 Check for syntax errors, then stop.
2545 ftest-coverage
2546 Common Report Var(flag_test_coverage)
2547 Create data files needed by \"gcov\".
2549 fthread-jumps
2550 Common Report Var(flag_thread_jumps) Optimization
2551 Perform jump threading optimizations.
2553 ftime-report
2554 Common Report Var(time_report)
2555 Report the time taken by each compiler pass.
2557 ftime-report-details
2558 Common Report Var(time_report_details)
2559 Record times taken by sub-phases separately.
2561 ftls-model=
2562 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2563 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec]      Set the default thread-local storage code generation model.
2565 Enum
2566 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2568 EnumValue
2569 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2571 EnumValue
2572 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2574 EnumValue
2575 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2577 EnumValue
2578 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2580 ftoplevel-reorder
2581 Common Report Var(flag_toplevel_reorder) Init(2)
2582 Reorder top level functions, variables, and asms.
2584 ftracer
2585 Common Report Var(flag_tracer) Optimization
2586 Perform superblock formation via tail duplication.
2588 ftrampolines
2589 Common Report Var(flag_trampolines) Init(0)
2590 For targets that normally need trampolines for nested functions, always
2591 generate them instead of using descriptors.
2593 ; Zero means that floating-point math operations cannot generate a
2594 ; (user-visible) trap.  This is the case, for example, in nonstop
2595 ; IEEE 754 arithmetic.
2596 ftrapping-math
2597 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
2598 Assume floating-point operations can trap.
2600 ftrapv
2601 Common Report Var(flag_trapv) Optimization
2602 Trap for signed overflow in addition, subtraction and multiplication.
2604 ftree-ccp
2605 Common Report Var(flag_tree_ccp) Optimization
2606 Enable SSA-CCP optimization on trees.
2608 ftree-bit-ccp
2609 Common Report Var(flag_tree_bit_ccp) Optimization
2610 Enable SSA-BIT-CCP optimization on trees.
2612 ftree-store-ccp
2613 Common Ignore
2614 Does nothing.  Preserved for backward compatibility.
2616 ftree-ch
2617 Common Report Var(flag_tree_ch) Optimization
2618 Enable loop header copying on trees.
2620 ftree-coalesce-inlined-vars
2621 Common Ignore RejectNegative
2622 Does nothing.  Preserved for backward compatibility.
2624 ftree-coalesce-vars
2625 Common Report Var(flag_tree_coalesce_vars) Optimization
2626 Enable SSA coalescing of user variables.
2628 ftree-copyrename
2629 Common Ignore
2630 Does nothing.  Preserved for backward compatibility.
2632 ftree-copy-prop
2633 Common Report Var(flag_tree_copy_prop) Optimization
2634 Enable copy propagation on trees.
2636 ftree-store-copy-prop
2637 Common Ignore
2638 Does nothing.  Preserved for backward compatibility.
2640 ftree-cselim
2641 Common Report Var(flag_tree_cselim) Init(2) Optimization
2642 Transform condition stores into unconditional ones.
2644 ftree-switch-conversion
2645 Common Report Var(flag_tree_switch_conversion) Optimization
2646 Perform conversions of switch initializations.
2648 ftree-dce
2649 Common Report Var(flag_tree_dce) Optimization
2650 Enable SSA dead code elimination optimization on trees.
2652 ftree-dominator-opts
2653 Common Report Var(flag_tree_dom) Optimization
2654 Enable dominator optimizations.
2656 ftree-tail-merge
2657 Common Report Var(flag_tree_tail_merge) Optimization
2658 Enable tail merging on trees.
2660 ftree-dse
2661 Common Report Var(flag_tree_dse) Optimization
2662 Enable dead store elimination.
2664 ftree-forwprop
2665 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2666 Enable forward propagation on trees.
2668 ftree-fre
2669 Common Report Var(flag_tree_fre) Optimization
2670 Enable Full Redundancy Elimination (FRE) on trees.
2672 foptimize-strlen
2673 Common Report Var(flag_optimize_strlen) Optimization
2674 Enable string length optimizations on trees.
2676 fisolate-erroneous-paths-dereference
2677 Common Report Var(flag_isolate_erroneous_paths_dereference) Optimization
2678 Detect paths that trigger erroneous or undefined behavior due to
2679 dereferencing a null pointer.  Isolate those paths from the main control
2680 flow and turn the statement with erroneous or undefined behavior into a trap.
2682 fisolate-erroneous-paths-attribute
2683 Common Report Var(flag_isolate_erroneous_paths_attribute) Optimization
2684 Detect paths that trigger erroneous or undefined behavior due to a null value
2685 being used in a way forbidden by a returns_nonnull or nonnull
2686 attribute.  Isolate those paths from the main control flow and turn the
2687 statement with erroneous or undefined behavior into a trap.
2689 ftree-loop-distribution
2690 Common Report Var(flag_tree_loop_distribution) Optimization
2691 Enable loop distribution on trees.
2693 ftree-loop-distribute-patterns
2694 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2695 Enable loop distribution for patterns transformed into a library call.
2697 ftree-loop-im
2698 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2699 Enable loop invariant motion on trees.
2701 ftree-loop-linear
2702 Common Alias(floop-nest-optimize)
2703 Enable loop nest transforms.  Same as -floop-nest-optimize.
2705 ftree-loop-ivcanon
2706 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2707 Create canonical induction variables in loops.
2709 ftree-loop-optimize
2710 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2711 Enable loop optimizations on tree level.
2713 ftree-parallelize-loops=
2714 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1) Optimization
2715 -ftree-parallelize-loops=<number>       Enable automatic parallelization of loops.
2717 ftree-phiprop
2718 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2719 Enable hoisting loads from conditional pointers.
2721 ftree-pre
2722 Common Report Var(flag_tree_pre) Optimization
2723 Enable SSA-PRE optimization on trees.
2725 ftree-partial-pre
2726 Common Report Var(flag_tree_partial_pre) Optimization
2727 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination.
2729 ftree-pta
2730 Common Report Var(flag_tree_pta) Optimization
2731 Perform function-local points-to analysis on trees.
2733 ftree-reassoc
2734 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2735 Enable reassociation on tree level.
2737 ftree-salias
2738 Common Ignore
2739 Does nothing.  Preserved for backward compatibility.
2741 ftree-sink
2742 Common Report Var(flag_tree_sink) Optimization
2743 Enable SSA code sinking on trees.
2745 ftree-slsr
2746 Common Report Var(flag_tree_slsr) Optimization
2747 Perform straight-line strength reduction.
2749 ftree-sra
2750 Common Report Var(flag_tree_sra) Optimization
2751 Perform scalar replacement of aggregates.
2753 ftree-ter
2754 Common Report Var(flag_tree_ter) Optimization
2755 Replace temporary expressions in the SSA->normal pass.
2757 ftree-lrs
2758 Common Report Var(flag_tree_live_range_split) Optimization
2759 Perform live range splitting during the SSA->normal pass.
2761 ftree-vrp
2762 Common Report Var(flag_tree_vrp) Init(0) Optimization
2763 Perform Value Range Propagation on trees.
2765 fsplit-paths
2766 Common Report Var(flag_split_paths) Init(0) Optimization
2767 Split paths leading to loop backedges.
2769 funconstrained-commons
2770 Common Var(flag_unconstrained_commons) Optimization
2771 Assume common declarations may be overridden with ones with a larger
2772 trailing array.
2774 funit-at-a-time
2775 Common Report Var(flag_unit_at_a_time) Init(1)
2776 Compile whole compilation unit at a time.
2778 funroll-loops
2779 Common Report Var(flag_unroll_loops) Optimization
2780 Perform loop unrolling when iteration count is known.
2782 funroll-all-loops
2783 Common Report Var(flag_unroll_all_loops) Optimization
2784 Perform loop unrolling for all loops.
2786 ; Nonzero means that loop optimizer may assume that the induction variables
2787 ; that control loops do not overflow and that the loops with nontrivial
2788 ; exit condition are not infinite
2789 funsafe-loop-optimizations
2790 Common Ignore
2791 Does nothing.  Preserved for backward compatibility.
2793 fassociative-math
2794 Common Report Var(flag_associative_math) SetByCombined Optimization
2795 Allow optimization for floating-point arithmetic which may change the
2796 result of the operation due to rounding.
2798 freciprocal-math
2799 Common Report Var(flag_reciprocal_math) SetByCombined Optimization
2800 Same as -fassociative-math for expressions which include division.
2802 ; Nonzero means that unsafe floating-point math optimizations are allowed
2803 ; for the sake of speed.  IEEE compliance is not guaranteed, and operations
2804 ; are allowed to assume that their arguments and results are "normal"
2805 ; (e.g., nonnegative for SQRT).
2806 funsafe-math-optimizations
2807 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2808 Allow math optimizations that may violate IEEE or ISO standards.
2810 funswitch-loops
2811 Common Report Var(flag_unswitch_loops) Optimization
2812 Perform loop unswitching.
2814 fsplit-loops
2815 Common Report Var(flag_split_loops) Optimization
2816 Perform loop splitting.
2818 fversion-loops-for-strides
2819 Common Report Var(flag_version_loops_for_strides) Optimization
2820 Version loops based on whether indices have a stride of one.
2822 funwind-tables
2823 Common Report Var(flag_unwind_tables) Optimization
2824 Just generate unwind tables for exception handling.
2826 fuse-ld=bfd
2827 Common Driver Negative(fuse-ld=gold)
2828 Use the bfd linker instead of the default linker.
2830 fuse-ld=gold
2831 Common Driver Negative(fuse-ld=bfd)
2832 Use the gold linker instead of the default linker.
2834 fuse-ld=lld
2835 Common Driver Negative(fuse-ld=lld)
2836 Use the lld LLVM linker instead of the default linker.
2838 fuse-linker-plugin
2839 Common Undocumented Var(flag_use_linker_plugin)
2841 ; Positive if we should track variables, negative if we should run
2842 ; the var-tracking pass only to discard debug annotations, zero if
2843 ; we're not to run it.  When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2844 ; will be set according to optimize, debug_info_level and debug_hooks
2845 ; in process_options ().
2846 fvar-tracking
2847 Common Report Var(flag_var_tracking) Init(2) PerFunction
2848 Perform variable tracking.
2850 ; Positive if we should track variables at assignments, negative if
2851 ; we should run the var-tracking pass only to discard debug
2852 ; annotations.  When flag_var_tracking_assignments ==
2853 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2854 fvar-tracking-assignments
2855 Common Report Var(flag_var_tracking_assignments) Init(2) PerFunction
2856 Perform variable tracking by annotating assignments.
2858 ; Nonzero if we should toggle flag_var_tracking_assignments after
2859 ; processing options and computing its default.  */
2860 fvar-tracking-assignments-toggle
2861 Common Report Var(flag_var_tracking_assignments_toggle) PerFunction
2862 Toggle -fvar-tracking-assignments.
2864 ; Positive if we should track uninitialized variables, negative if
2865 ; we should run the var-tracking pass only to discard debug
2866 ; annotations.  When flag_var_tracking_uninit == AUTODETECT_VALUE it
2867 ; will be set according to flag_var_tracking.
2868 fvar-tracking-uninit
2869 Common Report Var(flag_var_tracking_uninit) PerFunction
2870 Perform variable tracking and also tag variables that are uninitialized.
2872 ; Alias to enable both -ftree-loop-vectorize and -ftree-slp-vectorize.
2873 ftree-vectorize
2874 Common Report Optimization
2875 Enable vectorization on trees.
2877 ftree-vectorizer-verbose=
2878 Common Joined RejectNegative Ignore
2879 Does nothing.  Preserved for backward compatibility.
2881 ftree-loop-vectorize
2882 Common Report Var(flag_tree_loop_vectorize) Optimization EnabledBy(ftree-vectorize)
2883 Enable loop vectorization on trees.
2885 ftree-slp-vectorize
2886 Common Report Var(flag_tree_slp_vectorize) Optimization EnabledBy(ftree-vectorize)
2887 Enable basic block vectorization (SLP) on trees.
2889 fvect-cost-model=
2890 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT) Optimization
2891 -fvect-cost-model=[unlimited|dynamic|cheap]     Specifies the cost model for vectorization.
2893 fsimd-cost-model=
2894 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED) Optimization
2895 -fsimd-cost-model=[unlimited|dynamic|cheap]     Specifies the vectorization cost model for code marked with a simd directive.
2897 Enum
2898 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
2900 EnumValue
2901 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
2903 EnumValue
2904 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
2906 EnumValue
2907 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
2909 fvect-cost-model
2910 Common Alias(fvect-cost-model=,dynamic,unlimited)
2911 Enables the dynamic vectorizer cost model.  Preserved for backward compatibility.
2913 ftree-vect-loop-version
2914 Common Ignore
2915 Does nothing. Preserved for backward compatibility.
2917 ftree-scev-cprop
2918 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2919 Enable copy propagation of scalar-evolution information.
2921 ; -fverbose-asm causes extra commentary information to be produced in
2922 ; the generated assembly code (to make it more readable).  This option
2923 ; is generally only of use to those who actually need to read the
2924 ; generated assembly code (perhaps while debugging the compiler itself).
2925 ; -fno-verbose-asm, the default, causes the extra information
2926 ; to not be added and is useful when comparing two assembler files.
2927 fverbose-asm
2928 Common Report Var(flag_verbose_asm)
2929 Add extra commentary to assembler output.
2931 fvisibility=
2932 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2933 -fvisibility=[default|internal|hidden|protected]        Set the default symbol visibility.
2935 Enum
2936 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2938 EnumValue
2939 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2941 EnumValue
2942 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2944 EnumValue
2945 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2947 EnumValue
2948 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2950 fvtable-verify=
2951 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
2952 Validate vtable pointers before using them.
2954 Enum
2955 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
2957 EnumValue
2958 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
2960 EnumValue
2961 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
2963 EnumValue
2964 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
2966 fvtv-counts
2967 Common Var(flag_vtv_counts)
2968 Output vtable verification counters.
2970 fvtv-debug
2971 Common Var(flag_vtv_debug)
2972 Output vtable verification pointer sets information.
2974 fvpt
2975 Common Report Var(flag_value_profile_transformations) Optimization
2976 Use expression value profiles in optimizations.
2978 fweb
2979 Common Report Var(flag_web) Init(2) Optimization
2980 Construct webs and split unrelated uses of single variable.
2982 ftree-builtin-call-dce
2983 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2984 Enable conditional dead code elimination for builtin calls.
2986 fwhole-program
2987 Common Report Var(flag_whole_program) Init(0)
2988 Perform whole program optimizations.
2990 fwrapv-pointer
2991 Common Report Var(flag_wrapv_pointer) Optimization
2992 Assume pointer overflow wraps around.
2994 fwrapv
2995 Common Report Var(flag_wrapv) Optimization
2996 Assume signed arithmetic overflow wraps around.
2998 fzero-initialized-in-bss
2999 Common Report Var(flag_zero_initialized_in_bss) Init(1)
3000 Put zero initialized data in the bss section.
3003 Common Driver RejectNegative JoinedOrMissing
3004 Generate debug information in default format.
3006 gas-loc-support
3007 Common Driver Var(dwarf2out_as_loc_support) Init(2)
3008 Assume assembler support for (DWARF2+) .loc directives.
3010 gas-locview-support
3011 Common Driver Var(dwarf2out_as_locview_support) Init(2)
3012 Assume assembler support for view in (DWARF2+) .loc directives.
3014 gcoff
3015 Common Driver WarnRemoved
3016 Does nothing.  Preserved for backward compatibility.
3018 gcoff1
3019 Common Driver WarnRemoved
3020 Does nothing.  Preserved for backward compatibility.
3022 gcoff2
3023 Common Driver WarnRemoved
3024 Does nothing.  Preserved for backward compatibility.
3026 gcoff3
3027 Common Driver WarnRemoved
3028 Does nothing.  Preserved for backward compatibility.
3030 gcolumn-info
3031 Common Driver Var(debug_column_info,1) Init(1)
3032 Record DW_AT_decl_column and DW_AT_call_column in DWARF.
3034 gdwarf
3035 Common Driver JoinedOrMissing Negative(gdwarf-)
3036 Generate debug information in default version of DWARF format.
3038 gdwarf-
3039 Common Driver Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
3040 Generate debug information in DWARF v2 (or later) format.
3042 ggdb
3043 Common Driver JoinedOrMissing
3044 Generate debug information in default extended format.
3046 ginline-points
3047 Common Driver Var(debug_inline_points) Init(2)
3048 Generate extended entry point information for inlined functions.
3050 ginternal-reset-location-views
3051 Common Driver Var(debug_internal_reset_location_views) Init(2)
3052 Compute locview reset points based on insn length estimates.
3054 gno-
3055 RejectNegative Joined Undocumented
3056 ; Catch the gno- prefix, so it doesn't backtrack to g<level>.
3058 gno-pubnames
3059 Common Driver Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
3060 Don't generate DWARF pubnames and pubtypes sections.
3062 gpubnames
3063 Common Driver Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
3064 Generate DWARF pubnames and pubtypes sections.
3066 ggnu-pubnames
3067 Common Driver Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
3068 Generate DWARF pubnames and pubtypes sections with GNU extensions.
3070 grecord-gcc-switches
3071 Common Driver Var(dwarf_record_gcc_switches) Init(1)
3072 Record gcc command line switches in DWARF DW_AT_producer.
3074 gsplit-dwarf
3075 Common Driver Var(dwarf_split_debug_info) Init(0)
3076 Generate debug information in separate .dwo files.
3078 gstabs
3079 Common Driver JoinedOrMissing Negative(gstabs+)
3080 Generate debug information in STABS format.
3082 gstabs+
3083 Common Driver JoinedOrMissing Negative(gvms)
3084 Generate debug information in extended STABS format.
3086 gstatement-frontiers
3087 Common Driver Var(debug_nonbind_markers_p) Init(2)
3088 Emit progressive recommended breakpoint locations.
3090 gstrict-dwarf
3091 Common Driver Report Var(dwarf_strict) Init(0)
3092 Don't emit DWARF additions beyond selected version.
3094 gdescribe-dies
3095 Common Driver Report Var(flag_describe_dies) Init(0)
3096 Add description attributes to some DWARF DIEs that have no name attribute.
3098 gtoggle
3099 Common Driver Report Var(flag_gtoggle)
3100 Toggle debug information generation.
3102 gvariable-location-views
3103 Common Driver Var(debug_variable_location_views, 1) Init(2)
3104 Augment variable location lists with progressive views.
3106 gvariable-location-views=incompat5
3107 Common Driver RejectNegative Var(debug_variable_location_views, -1) Init(2)
3109 gvms
3110 Common Driver JoinedOrMissing Negative(gxcoff)
3111 Generate debug information in VMS format.
3113 gxcoff
3114 Common Driver JoinedOrMissing Negative(gxcoff+)
3115 Generate debug information in XCOFF format.
3117 gxcoff+
3118 Common Driver JoinedOrMissing Negative(gdwarf)
3119 Generate debug information in extended XCOFF format.
3121 Enum
3122 Name(compressed_debug_sections) Type(int)
3124 ; Since -gz= is completely handled in specs, the values aren't used and we
3125 ; assign arbitrary constants.
3126 EnumValue
3127 Enum(compressed_debug_sections) String(none) Value(0)
3129 EnumValue
3130 Enum(compressed_debug_sections) String(zlib) Value(1)
3132 EnumValue
3133 Enum(compressed_debug_sections) String(zlib-gnu) Value(2)
3136 Common Driver
3137 Generate compressed debug sections.
3140 Common Driver RejectNegative Joined Enum(compressed_debug_sections)
3141 -gz=<format>    Generate compressed debug sections in format <format>.
3144 Driver Joined Separate
3146 iplugindir=
3147 Common Joined Var(plugindir_string) Init(0)
3148 -iplugindir=<dir>       Set <dir> to be the default plugin directory.
3150 imultiarch
3151 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
3152 -imultiarch <dir>       Set <dir> to be the multiarch include subdirectory.
3155 Driver Joined Separate
3158 Driver
3160 no-canonical-prefixes
3161 Driver
3163 nodefaultlibs
3164 Driver
3166 nostartfiles
3167 Driver
3169 nolibc
3170 Driver
3172 nostdlib
3173 Driver
3176 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
3177 -o <file>       Place output into <file>.
3180 Common Var(profile_flag)
3181 Enable function profiling.
3183 pass-exit-codes
3184 Driver Var(pass_exit_codes)
3186 pedantic
3187 Common Alias(Wpedantic)
3189 pedantic-errors
3190 Common Var(flag_pedantic_errors)
3191 Like -pedantic but issue them as errors.
3194 Driver
3196 pipe
3197 Driver Var(use_pipes)
3199 print-file-name=
3200 Driver JoinedOrMissing Var(print_file_name)
3202 print-libgcc-file-name
3203 Driver
3205 print-multi-directory
3206 Driver Var(print_multi_directory)
3208 print-multi-lib
3209 Driver Var(print_multi_lib)
3211 print-multi-os-directory
3212 Driver Var(print_multi_os_directory)
3214 print-multiarch
3215 Driver Var(print_multiarch)
3217 print-prog-name=
3218 Driver JoinedOrMissing Var(print_prog_name)
3220 print-search-dirs
3221 Driver Var(print_search_dirs)
3223 print-sysroot
3224 Driver Var(print_sysroot)
3226 print-sysroot-headers-suffix
3227 Driver Var(print_sysroot_headers_suffix)
3229 quiet
3230 Common Var(quiet_flag) RejectDriver
3231 Do not display functions compiled or elapsed time.
3234 Driver
3237 Driver
3239 save-temps
3240 Driver
3242 save-temps=
3243 Driver Joined
3246 Driver
3248 time
3249 Driver Var(report_times)
3251 time=
3252 Driver JoinedOrMissing
3255 Driver Joined Separate
3257 undef
3258 Driver
3259 ; C option, but driver must not handle as "-u ndef".
3262 Common Driver Var(verbose_flag)
3263 Enable verbose output.
3265 version
3266 Common Var(version_flag) RejectDriver
3267 Display the compiler's version.
3270 Common Var(inhibit_warnings)
3271 Suppress warnings.
3273 wrapper
3274 Driver Separate Var(wrapper_string)
3277 Driver Joined Separate
3279 shared
3280 Driver RejectNegative Negative(static-pie)
3281 Create a shared library.
3283 shared-libgcc
3284 Driver
3286 specs
3287 Driver Separate Alias(specs=)
3289 specs=
3290 Driver Joined
3292 static
3293 Driver
3295 static-libgcc
3296 Driver
3298 static-libgfortran
3299 Driver
3300 ; Documented for Fortran, but always accepted by driver.
3302 static-libstdc++
3303 Driver
3305 static-libgo
3306 Driver
3307 ; Documented for Go, but always accepted by driver.
3309 static-libasan
3310 Driver
3312 static-libtsan
3313 Driver
3315 static-liblsan
3316 Driver
3318 static-libubsan
3319 Driver
3321 symbolic
3322 Driver
3324 no-pie
3325 Driver RejectNegative Negative(shared)
3326 Don't create a dynamically linked position independent executable.
3329 Driver RejectNegative Negative(no-pie)
3330 Create a dynamically linked position independent executable.
3332 static-pie
3333 Driver RejectNegative Negative(pie)
3334 Create a static position independent executable.
3337 Driver Joined Separate
3339 fipa-ra
3340 Common Report Var(flag_ipa_ra) Optimization
3341 Use caller save register across calls if possible.
3343 ; This comment is to ensure we retain the blank line above.