Fix ICE in lto_symtab_merge_symbols_1 (PR lto/88004).
[official-gcc.git] / gcc / common.opt
blob72a713593c3da10c0e5596e24ef164ff7f40dbbc
1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003-2018 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 Joined RejectNegative UInteger Var(warn_attribute_alias) Init(1) Warning IntegerRange(0, 2)
555 Warn about type safety and similar errors and mismatches in attribute alias and related.
557 Wno-attribute-alias
558 Common Alias(Wattribute_alias=, 0, 0) Warning
559 Disable -Wattribute-alias.
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-declarations
583 Common Var(warn_deprecated_decl) Init(1) Warning
584 Warn about uses of __attribute__((deprecated)) declarations.
586 Wdisabled-optimization
587 Common Var(warn_disabled_optimization) Warning
588 Warn when an optimization pass is disabled.
590 Werror
591 Common Var(warnings_are_errors)
592 Treat all warnings as errors.
594 Werror=
595 Common Joined
596 Treat specified warning as error.
598 Wextra
599 Common Var(extra_warnings) Warning
600 Print extra (possibly unwanted) warnings.
602 Wfatal-errors
603 Common Var(flag_fatal_errors)
604 Exit on the first error occurred.
606 Wframe-larger-than=
607 Common RejectNegative Joined Host_Wide_Int ByteSize Warning Var(warn_frame_larger_than_size) Init(HOST_WIDE_INT_MAX)
608 -Wframe-larger-than=<byte-size> Warn if a function's stack frame requires in excess of <byte-size>.
610 Wfree-nonheap-object
611 Common Var(warn_free_nonheap_object) Init(1) Warning
612 Warn when attempting to free a non-heap object.
614 Whsa
615 Common Var(warn_hsa) Init(1) Warning
616 Warn when a function cannot be expanded to HSAIL.
618 Wimplicit-fallthrough
619 Common Alias(Wimplicit-fallthrough=,3,0) Warning
621 Wimplicit-fallthrough=
622 Common Var(warn_implicit_fallthrough) RejectNegative Joined UInteger Warning IntegerRange(0, 5)
623 Warn when a switch case falls through.
625 Winline
626 Common Var(warn_inline) Warning
627 Warn when an inlined function cannot be inlined.
629 Winvalid-memory-model
630 Common Var(warn_invalid_memory_model) Init(1) Warning
631 Warn when an atomic memory model parameter is known to be outside the valid range.
633 Wlarger-than-
634 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
636 Wlarger-than=
637 Common RejectNegative Joined Host_Wide_Int ByteSize Warning Var(warn_larger_than_size) Init(HOST_WIDE_INT_MAX)
638 -Wlarger-than=<byte-size>       Warn if an object's size exceeds <byte-size>.
640 Wnonnull-compare
641 Var(warn_nonnull_compare) Warning
642 Warn if comparing pointer parameter with nonnull attribute with NULL.
644 Wnull-dereference
645 Common Var(warn_null_dereference) Warning
646 Warn if dereferencing a NULL pointer may lead to erroneous or undefined behavior.
648 Wunsafe-loop-optimizations
649 Common Ignore Warning
650 Does nothing. Preserved for backward compatibility.
652 Wmissing-noreturn
653 Common Warning Alias(Wsuggest-attribute=noreturn)
655 Wodr
656 Common Var(warn_odr_violations) Init(1) Warning
657 Warn about some C++ One Definition Rule violations during link time optimization.
659 Woverflow
660 Common Var(warn_overflow) Init(1) Warning
661 Warn about overflow in arithmetic expressions.
663 Wlto-type-mismatch
664 Common Var(warn_lto_type_mismatch) Init(1) Warning
665 During link time optimization warn about mismatched types of global declarations.
667 Wpacked
668 Common Var(warn_packed) Warning
669 Warn when the packed attribute has no effect on struct layout.
671 Wpadded
672 Common Var(warn_padded) Warning
673 Warn when padding is required to align structure members.
675 Wpedantic
676 Common Var(pedantic) Init(0) Warning
677 Issue warnings needed for strict compliance to the standard.
679 Wreturn-local-addr
680 Common Var(warn_return_local_addr) Init(1) Warning
681 Warn about returning a pointer/reference to a local or temporary variable.
683 Wshadow
684 Common Var(warn_shadow) Warning
685 Warn when one variable shadows another.  Same as -Wshadow=global.
687 Wshadow=global
688 Common Warning Alias(Wshadow)
689 Warn when one variable shadows another (globally).
691 Wshadow=local
692 Common Var(warn_shadow_local) Warning EnabledBy(Wshadow)
693 Warn when one local variable shadows another local variable or parameter.
695 Wshadow-local
696 Common Warning Undocumented Alias(Wshadow=local)
698 Wshadow=compatible-local
699 Common Var(warn_shadow_compatible_local) Warning EnabledBy(Wshadow=local)
700 Warn when one local variable shadows another local variable or parameter of compatible type.
702 Wshadow-compatible-local
703 Common Warning Undocumented Alias(Wshadow=compatible-local)
705 Wstack-protector
706 Common Var(warn_stack_protect) Warning
707 Warn when not issuing stack smashing protection for some reason.
709 Wstack-usage=
710 Common Joined RejectNegative Host_Wide_Int ByteSize Var(warn_stack_usage) Warning Init(HOST_WIDE_INT_MAX)
711 -Wstack-usage=<byte-size>       Warn if stack usage might exceed <byte-size>.
713 Wstrict-aliasing
714 Common Warning
715 Warn about code which might break strict aliasing rules.
717 Wstrict-aliasing=
718 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
719 Warn about code which might break strict aliasing rules.
721 Wstrict-overflow
722 Common Warning
723 Warn about optimizations that assume that signed overflow is undefined.
725 Wstrict-overflow=
726 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
727 Warn about optimizations that assume that signed overflow is undefined.
729 Wsuggest-attribute=cold
730 Common Var(warn_suggest_attribute_cold) Warning
731 Warn about functions which might be candidates for __attribute__((cold)).
733 Wsuggest-attribute=const
734 Common Var(warn_suggest_attribute_const) Warning
735 Warn about functions which might be candidates for __attribute__((const)).
737 Wsuggest-attribute=pure
738 Common Var(warn_suggest_attribute_pure) Warning
739 Warn about functions which might be candidates for __attribute__((pure)).
741 Wsuggest-attribute=noreturn
742 Common Var(warn_suggest_attribute_noreturn) Warning
743 Warn about functions which might be candidates for __attribute__((noreturn)).
745 Wsuggest-attribute=malloc
746 Common Var(warn_suggest_attribute_malloc) Warning
747 Warn about functions which might be candidates for __attribute__((malloc)).
749 Wsuggest-final-types
750 Common Var(warn_suggest_final_types) Warning
751 Warn about C++ polymorphic types where adding final keyword would improve code quality.
753 Wsuggest-final-methods
754 Common Var(warn_suggest_final_methods) Warning
755 Warn about C++ virtual methods where adding final keyword would improve code quality.
757 Wswitch-unreachable
758 Common Var(warn_switch_unreachable) Warning Init(1)
759 Warn about statements between switch's controlling expression and the first
760 case.
762 Wsystem-headers
763 Common Var(warn_system_headers) Warning
764 Do not suppress warnings from system headers.
766 Wtrampolines
767 Common Var(warn_trampolines) Warning
768 Warn whenever a trampoline is generated.
770 Wtype-limits
771 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
772 Warn if a comparison is always true or always false due to the limited range of the data type.
774 Wuninitialized
775 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
776 Warn about uninitialized automatic variables.
778 Wmaybe-uninitialized
779 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
780 Warn about maybe uninitialized automatic variables.
782 Wunreachable-code
783 Common Ignore Warning
784 Does nothing. Preserved for backward compatibility.
786 Wunused
787 Common Var(warn_unused) Init(0) Warning
788 Enable all -Wunused- warnings.
790 Wunused-but-set-parameter
791 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
792 Warn when a function parameter is only set, otherwise unused.
794 Wunused-but-set-variable
795 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
796 Warn when a variable is only set, otherwise unused.
798 Wunused-function
799 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
800 Warn when a function is unused.
802 Wunused-label
803 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
804 Warn when a label is unused.
806 Wunused-parameter
807 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
808 Warn when a function parameter is unused.
810 Wunused-value
811 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
812 Warn when an expression value is unused.
814 Wunused-variable
815 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
816 Warn when a variable is unused.
818 Wcoverage-mismatch
819 Common Var(warn_coverage_mismatch) Init(1) Warning
820 Warn in case profiles in -fprofile-use do not match.
822 Wmissing-profile
823 Common Var(warn_missing_profile) Init(1) Warning
824 Warn in case profiles in -fprofile-use do not exist.
826 Wvector-operation-performance
827 Common Var(warn_vector_operation_performance) Warning
828 Warn when a vector operation is compiled outside the SIMD.
830 Xassembler
831 Driver Separate
833 Xlinker
834 Driver Separate
836 Xpreprocessor
837 Driver Separate
840 Driver
842 aux-info
843 Common Separate Var(aux_info_file_name)
844 -aux-info <file>        Emit declaration information into <file>.
846 aux-info=
847 Common Joined Alias(aux-info)
849 auxbase
850 Common Separate RejectDriver Var(aux_base_name)
852 auxbase-strip
853 Common Separate RejectDriver
855 coverage
856 Driver
859 Driver
862 Common Joined
863 -d<letters>     Enable dumps from specific passes of the compiler.
865 dumpbase
866 Common Separate Var(dump_base_name)
867 -dumpbase <file>        Set the file basename to be used for dumps.
869 dumpdir
870 Common Separate Var(dump_dir_name)
871 -dumpdir <dir>  Set the directory name to be used for dumps.
873 dumpmachine
874 Driver
876 dumpspecs
877 Driver
879 dumpversion
880 Driver
882 dumpfullversion
883 Driver
886 Driver Joined Separate
888 ; This option has historically been passed down to the linker by an
889 ; accident of a %{e*} spec, so ensure it continues to be passed down
890 ; as a single option.  The supported option for this purpose is
891 ; -rdynamic.  See PR 47390.
892 export-dynamic
893 Driver Undocumented
895 ; The version of the C++ ABI in use.  The following values are allowed:
897 ; 0: The version of the ABI believed most conformant with the C++ ABI
898 ;    specification.  This ABI may change as bugs are discovered and fixed.
899 ;    Therefore, 0 will not necessarily indicate the same ABI in different
900 ;    versions of G++.
902 ; 1: The version of the ABI first used in G++ 3.2.  No longer selectable.
904 ; 2: The version of the ABI first used in G++ 3.4, and the default
905 ;    until GCC 4.9.
907 ; 3: The version of the ABI that fixes the missing underscore
908 ;    in template non-type arguments of pointer type.
910 ; 4: The version of the ABI that introduces unambiguous mangling of
911 ;    vector types.  First selectable in G++ 4.5.
913 ; 5: The version of the ABI that ignores attribute const/noreturn
914 ;    in function pointer mangling, and corrects mangling of decltype and
915 ;    function parameters used in other parameters and the return type.
916 ;    First selectable in G++ 4.6.
918 ; 6: The version of the ABI that doesn't promote scoped enums to int and
919 ;    changes the mangling of template argument packs, const/static_cast,
920 ;    prefix ++ and --, and a class scope function used as a template
921 ;    argument.
922 ;    First selectable in G++ 4.7.
924 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
925 ;    corrects the mangling of lambdas in default argument scope.
926 ;    First selectable in G++ 4.8.
928 ; 8: The version of the ABI that corrects the substitution behavior of
929 ;    function types with function-cv-qualifiers.
930 ;    First selectable in G++ 4.9 and default in G++ 5.
932 ; 9: The version of the ABI that corrects the alignment of nullptr_t.
933 ;    First selectable and default in G++ 5.2.
935 ; 10: The version of the ABI that mangles attributes that affect type
936 ;     identity, such as ia32 calling convention attributes (stdcall, etc.)
937 ;     Default in G++ 6 (set in c_common_post_options).
939 ; 11: The version of the ABI that corrects mangling of sizeof... expressions
940 ;     and introduces new inheriting constructor handling.
941 ;     Default in G++ 7.
943 ; 12: Corrects the calling convention for classes with only deleted copy/move
944 ;     constructors and changes passing/returning of empty records.
945 ;     Default in G++ 8.1.
947 ; 13: Fixes the accidental change in 12 to the calling convention for classes
948 ;     with deleted copy constructor and trivial move constructor.
949 ;     Default in G++ 8.2.
951 ; Additional positive integers will be assigned as new versions of
952 ; the ABI become the default version of the ABI.
953 fabi-version=
954 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(0)
955 The version of the C++ ABI in use.
957 faggressive-loop-optimizations
958 Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1)
959 Aggressively optimize loops using language constraints.
961 falign-functions
962 Common Report Var(flag_align_functions) Optimization
963 Align the start of functions.
965 falign-functions=
966 Common RejectNegative Joined Var(str_align_functions) Optimization
968 flimit-function-alignment
969 Common Report Var(flag_limit_function_alignment) Optimization Init(0)
971 falign-jumps
972 Common Report Var(flag_align_jumps) Optimization
973 Align labels which are only reached by jumping.
975 falign-jumps=
976 Common RejectNegative Joined Var(str_align_jumps) Optimization
978 falign-labels
979 Common Report Var(flag_align_labels) Optimization
980 Align all labels.
982 falign-labels=
983 Common RejectNegative Joined Var(str_align_labels) Optimization
985 falign-loops
986 Common Report Var(flag_align_loops) Optimization
987 Align the start of loops.
989 falign-loops=
990 Common RejectNegative Joined Var(str_align_loops) Optimization
992 fargument-alias
993 Common Ignore
994 Does nothing. Preserved for backward compatibility.
996 fargument-noalias
997 Common Ignore
998 Does nothing. Preserved for backward compatibility.
1000 fargument-noalias-global
1001 Common Ignore
1002 Does nothing. Preserved for backward compatibility.
1004 fargument-noalias-anything
1005 Common Ignore
1006 Does nothing. Preserved for backward compatibility.
1008 fsanitize=
1009 Common Driver Report Joined
1010 Select what to sanitize.
1012 fsanitize-coverage=
1013 Common Report Joined
1014 Select type of coverage sanitization.
1016 fasan-shadow-offset=
1017 Common Joined RejectNegative Var(common_deferred_options) Defer
1018 -fasan-shadow-offset=<number>   Use custom shadow memory offset.
1020 fsanitize-sections=
1021 Common Joined RejectNegative Var(common_deferred_options) Defer
1022 -fsanitize-sections=<sec1,sec2,...>     Sanitize global variables
1023 in user-defined sections.
1025 fsanitize-recover=
1026 Common Report Joined
1027 After diagnosing undefined behavior attempt to continue execution.
1029 fsanitize-recover
1030 Common Report
1031 This switch is deprecated; use -fsanitize-recover= instead.
1033 fsanitize-address-use-after-scope
1034 Common Driver Report Var(flag_sanitize_address_use_after_scope) Init(0)
1036 fsanitize-undefined-trap-on-error
1037 Common Driver Report Var(flag_sanitize_undefined_trap_on_error) Init(0)
1038 Use trap instead of a library function for undefined behavior sanitization.
1040 fasynchronous-unwind-tables
1041 Common Report Var(flag_asynchronous_unwind_tables) Optimization
1042 Generate unwind tables that are exact at each instruction boundary.
1044 fauto-inc-dec
1045 Common Report Var(flag_auto_inc_dec) Init(1) Optimization
1046 Generate auto-inc/dec instructions.
1048 fauto-profile
1049 Common Report Var(flag_auto_profile)
1050 Use sample profile information for call graph node weights. The default
1051 profile file is fbdata.afdo in 'pwd'.
1053 fauto-profile=
1054 Common Joined RejectNegative Var(auto_profile_file)
1055 Use sample profile information for call graph node weights. The profile
1056 file is specified in the argument.
1058 ; -fcheck-bounds causes gcc to generate array bounds checks.
1059 ; For C, C++ and ObjC: defaults off.
1060 ; For Java: defaults to on.
1061 ; For Fortran: defaults to off.
1062 fbounds-check
1063 Common Report Var(flag_bounds_check)
1064 Generate code to check bounds before indexing arrays.
1066 fbranch-count-reg
1067 Common Report Var(flag_branch_on_count_reg) Optimization
1068 Replace add, compare, branch with branch on count register.
1070 fbranch-probabilities
1071 Common Report Var(flag_branch_probabilities) Optimization
1072 Use profiling information for branch probabilities.
1074 fbranch-target-load-optimize
1075 Common Report Var(flag_branch_target_load_optimize) Optimization
1076 Perform branch target load optimization before prologue / epilogue threading.
1078 fbranch-target-load-optimize2
1079 Common Report Var(flag_branch_target_load_optimize2) Optimization
1080 Perform branch target load optimization after prologue / epilogue threading.
1082 fbtr-bb-exclusive
1083 Common Report Var(flag_btr_bb_exclusive) Optimization
1084 Restrict target load migration not to re-use registers in any basic block.
1086 fcall-saved-
1087 Common Joined RejectNegative Var(common_deferred_options) Defer
1088 -fcall-saved-<register> Mark <register> as being preserved across functions.
1090 fcall-used-
1091 Common Joined RejectNegative Var(common_deferred_options) Defer
1092 -fcall-used-<register>  Mark <register> as being corrupted by function calls.
1094 ; Nonzero for -fcaller-saves: allocate values in regs that need to
1095 ; be saved across function calls, if that produces overall better code.
1096 ; Optional now, so people can test it.
1097 fcaller-saves
1098 Common Report Var(flag_caller_saves) Optimization
1099 Save registers around function calls.
1101 fcheck-data-deps
1102 Common Ignore
1103 This switch is deprecated; do not use.
1105 fcheck-new
1106 Common Var(flag_check_new)
1107 Check the return value of new in C++.
1109 fchecking
1110 Common Var(flag_checking) Init(CHECKING_P ? ENABLE_EXTRA_CHECKING ? 2 : 1 : 0)
1111 Perform internal consistency checkings.
1113 fchecking=
1114 Common Joined RejectNegative UInteger Var(flag_checking)
1115 Perform internal consistency checkings.
1117 fcode-hoisting
1118 Common Report Var(flag_code_hoisting) Optimization
1119 Enable code hoisting.
1121 fcombine-stack-adjustments
1122 Common Report Var(flag_combine_stack_adjustments) Optimization
1123 Looks for opportunities to reduce stack adjustments and stack references.
1125 fcommon
1126 Common Report Var(flag_no_common,0)
1127 Do not put uninitialized globals in the common section.
1129 fcompare-debug
1130 Driver
1131 ; Converted by the driver to -fcompare-debug= options.
1133 fcompare-debug=
1134 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
1135 -fcompare-debug[=<opts>]        Compile with and without e.g. -gtoggle, and compare the final-insns dump.
1137 fcompare-debug-second
1138 Common Driver RejectNegative Var(flag_compare_debug)
1139 Run only the second compilation of -fcompare-debug.
1141 fcompare-elim
1142 Common Report Var(flag_compare_elim_after_reload) Optimization
1143 Perform comparison elimination after register allocation has finished.
1145 fconserve-stack
1146 Common Var(flag_conserve_stack) Optimization
1147 Do not perform optimizations increasing noticeably stack usage.
1149 fcprop-registers
1150 Common Report Var(flag_cprop_registers) Optimization
1151 Perform a register copy-propagation optimization pass.
1153 fcrossjumping
1154 Common Report Var(flag_crossjumping) Optimization
1155 Perform cross-jumping optimization.
1157 fcse-follow-jumps
1158 Common Report Var(flag_cse_follow_jumps) Optimization
1159 When running CSE, follow jumps to their targets.
1161 fcse-skip-blocks
1162 Common Ignore
1163 Does nothing.  Preserved for backward compatibility.
1165 fcx-limited-range
1166 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
1167 Omit range reduction step when performing complex division.
1169 fcx-fortran-rules
1170 Common Report Var(flag_cx_fortran_rules) Optimization
1171 Complex multiplication and division follow Fortran rules.
1173 fdata-sections
1174 Common Report Var(flag_data_sections)
1175 Place data items into their own section.
1177 fdbg-cnt-list
1178 Common Report Var(common_deferred_options) Defer
1179 List all available debugging counters with their limits and counts.
1181 fdbg-cnt=
1182 Common RejectNegative Joined Var(common_deferred_options) Defer
1183 -fdbg-cnt=<counter>[:<lower_limit>]:<upper_limit>[,<counter>:...]       Set the debug counter limit.
1185 fdebug-prefix-map=
1186 Common Joined RejectNegative Var(common_deferred_options) Defer
1187 -fdebug-prefix-map=<old>=<new> Map one directory name to another in debug information.
1189 ffile-prefix-map=
1190 Common Joined RejectNegative Var(common_deferred_options) Defer
1191 -ffile-prefix-map=<old>=<new> Map one directory name to another in compilation result.
1193 fdebug-types-section
1194 Common Report Var(flag_debug_types_section) Init(0)
1195 Output .debug_types section when using DWARF v4 debuginfo.
1197 ; Nonzero for -fdefer-pop: don't pop args after each function call
1198 ; instead save them up to pop many calls' args with one insns.
1199 fdefer-pop
1200 Common Report Var(flag_defer_pop) Optimization
1201 Defer popping functions args from stack until later.
1203 fdelayed-branch
1204 Common Report Var(flag_delayed_branch) Optimization
1205 Attempt to fill delay slots of branch instructions.
1207 fdelete-dead-exceptions
1208 Common Report Var(flag_delete_dead_exceptions) Init(0) Optimization
1209 Delete dead instructions that may throw exceptions.
1211 fdelete-null-pointer-checks
1212 Common Report Var(flag_delete_null_pointer_checks) Init(-1) Optimization
1213 Delete useless null pointer checks.
1215 fdevirtualize-at-ltrans
1216 Common Report Var(flag_ltrans_devirtualize)
1217 Stream extra data to support more aggressive devirtualization in LTO local transformation mode.
1219 fdevirtualize-speculatively
1220 Common Report Var(flag_devirtualize_speculatively) Optimization
1221 Perform speculative devirtualization.
1223 fdevirtualize
1224 Common Report Var(flag_devirtualize) Optimization
1225 Try to convert virtual calls to direct ones.
1227 fdiagnostics-show-location=
1228 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1229 -fdiagnostics-show-location=[once|every-line]   How often to emit source location at the beginning of line-wrapped diagnostics.
1231 ; Required for these enum values.
1232 SourceInclude
1233 pretty-print.h
1235 Enum
1236 Name(diagnostic_prefixing_rule) Type(int)
1238 EnumValue
1239 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1241 EnumValue
1242 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1244 fdiagnostics-show-caret
1245 Common Var(flag_diagnostics_show_caret) Init(1)
1246 Show the source line with a caret indicating the column.
1248 fdiagnostics-show-labels
1249 Common Var(flag_diagnostics_show_labels) Init(1)
1250 Show labels annotating ranges of source code when showing source
1252 fdiagnostics-show-line-numbers
1253 Common Var(flag_diagnostics_show_line_numbers) Init(1)
1254 Show line numbers in the left margin when showing source
1256 fdiagnostics-color
1257 Common Alias(fdiagnostics-color=,always,never)
1260 fdiagnostics-color=
1261 Driver Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1262 -fdiagnostics-color=[never|always|auto] Colorize diagnostics.
1264 ; Required for these enum values.
1265 SourceInclude
1266 diagnostic-color.h
1268 Enum
1269 Name(diagnostic_color_rule) Type(int)
1271 EnumValue
1272 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1274 EnumValue
1275 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1277 EnumValue
1278 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1280 fdiagnostics-format=
1281 Common Joined RejectNegative Enum(diagnostics_output_format)
1282 -fdiagnostics-format=[text|json] Select output format
1284 ; Required for these enum values.
1285 SourceInclude
1286 diagnostic.h
1288 Enum
1289 Name(diagnostics_output_format) Type(int)
1291 EnumValue
1292 Enum(diagnostics_output_format) String(text) Value(DIAGNOSTICS_OUTPUT_FORMAT_TEXT)
1294 EnumValue
1295 Enum(diagnostics_output_format) String(json) Value(DIAGNOSTICS_OUTPUT_FORMAT_JSON)
1297 fdiagnostics-parseable-fixits
1298 Common Var(flag_diagnostics_parseable_fixits)
1299 Print fix-it hints in machine-readable form.
1301 fdiagnostics-generate-patch
1302 Common Var(flag_diagnostics_generate_patch)
1303 Print fix-it hints to stderr in unified diff format.
1305 fdiagnostics-show-option
1306 Common Var(flag_diagnostics_show_option) Init(1)
1307 Amend appropriate diagnostic messages with the command line option that controls them.
1309 fdiagnostics-minimum-margin-width=
1310 Common Joined UInteger Var(diagnostics_minimum_margin_width) Init(6)
1311 Set minimum width of left margin of source code when showing source
1313 fdisable-
1314 Common Joined RejectNegative Var(common_deferred_options) Defer
1315 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass.
1317 fenable-
1318 Common Joined RejectNegative Var(common_deferred_options) Defer
1319 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass.
1321 fdump-
1322 Common Joined RejectNegative Var(common_deferred_options) Defer
1323 -fdump-<type>   Dump various compiler internals to a file.
1325 fdump-final-insns
1326 Driver RejectNegative
1328 fdump-final-insns=
1329 Common RejectNegative Joined Var(flag_dump_final_insns)
1330 -fdump-final-insns=filename     Dump to filename the insns at the end of translation.
1332 fdump-go-spec=
1333 Common RejectNegative Joined Var(flag_dump_go_spec)
1334 -fdump-go-spec=filename Write all declarations to file as Go code.
1336 fdump-noaddr
1337 Common Report Var(flag_dump_noaddr)
1338 Suppress output of addresses in debugging dumps.
1340 freport-bug
1341 Common Driver Var(flag_report_bug)
1342 Collect and dump debug information into temporary file if ICE in C/C++
1343 compiler occurred.
1345 fdump-internal-locations
1346 Common Var(flag_dump_locations) Init(0)
1347 Dump detailed information on GCC's internal representation of source code locations.
1349 fdump-passes
1350 Common Var(flag_dump_passes) Init(0)
1351 Dump optimization passes.
1353 fdump-unnumbered
1354 Common Report Var(flag_dump_unnumbered)
1355 Suppress output of instruction numbers, line number notes and addresses in debugging dumps.
1357 fdump-unnumbered-links
1358 Common Report Var(flag_dump_unnumbered_links)
1359 Suppress output of previous and next insn numbers in debugging dumps.
1361 fdwarf2-cfi-asm
1362 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1363 Enable CFI tables via GAS assembler directives.
1365 fearly-inlining
1366 Common Report Var(flag_early_inlining) Init(1) Optimization
1367 Perform early inlining.
1369 feliminate-dwarf2-dups
1370 Common Ignore
1371 Does nothing.  Preserved for backward compatibility.
1373 fipa-sra
1374 Common Report Var(flag_ipa_sra) Init(0) Optimization
1375 Perform interprocedural reduction of aggregates.
1377 feliminate-unused-debug-symbols
1378 Common Report Var(flag_debug_only_used_symbols)
1379 Perform unused symbol elimination in debug info.
1381 feliminate-unused-debug-types
1382 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1383 Perform unused type elimination in debug info.
1385 femit-class-debug-always
1386 Common Report Var(flag_emit_class_debug_always) Init(0)
1387 Do not suppress C++ class debug information.
1389 fexceptions
1390 Common Report Var(flag_exceptions) Optimization
1391 Enable exception handling.
1393 fexpensive-optimizations
1394 Common Report Var(flag_expensive_optimizations) Optimization
1395 Perform a number of minor, expensive optimizations.
1397 fexcess-precision=
1398 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT) SetByCombined
1399 -fexcess-precision=[fast|standard]      Specify handling of excess floating-point precision.
1401 Enum
1402 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1404 EnumValue
1405 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1407 EnumValue
1408 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1410 ; Whether we permit the extended set of values for FLT_EVAL_METHOD
1411 ; introduced in ISO/IEC TS 18661-3, or limit ourselves to those in C99/C11.
1412 fpermitted-flt-eval-methods=
1413 Common Joined RejectNegative Enum(permitted_flt_eval_methods) Var(flag_permitted_flt_eval_methods) Init(PERMITTED_FLT_EVAL_METHODS_DEFAULT)
1414 -fpermitted-flt-eval-methods=[c11|ts-18661]     Specify which values of FLT_EVAL_METHOD are permitted.
1416 Enum
1417 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)
1419 EnumValue
1420 Enum(permitted_flt_eval_methods) String(c11) Value(PERMITTED_FLT_EVAL_METHODS_C11)
1422 EnumValue
1423 Enum(permitted_flt_eval_methods) String(ts-18661-3) Value(PERMITTED_FLT_EVAL_METHODS_TS_18661)
1425 ffast-math
1426 Common Optimization
1428 ffat-lto-objects
1429 Common Var(flag_fat_lto_objects)
1430 Output lto objects containing both the intermediate language and binary output.
1432 ffinite-math-only
1433 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1434 Assume no NaNs or infinities are generated.
1436 ffixed-
1437 Common Joined RejectNegative Var(common_deferred_options) Defer
1438 -ffixed-<register>      Mark <register> as being unavailable to the compiler.
1440 ffloat-store
1441 Common Report Var(flag_float_store) Optimization
1442 Don't allocate floats and doubles in extended-precision registers.
1444 fforce-addr
1445 Common Ignore
1446 Does nothing.  Preserved for backward compatibility.
1448 fforward-propagate
1449 Common Report Var(flag_forward_propagate) Optimization
1450 Perform a forward propagation pass on RTL.
1452 ffp-contract=
1453 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST) Optimization
1454 -ffp-contract=[off|on|fast]     Perform floating-point expression contraction.
1456 Enum
1457 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1459 EnumValue
1460 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1462 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1463 EnumValue
1464 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1466 EnumValue
1467 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1469 ffp-int-builtin-inexact
1470 Common Report Var(flag_fp_int_builtin_inexact) Init(1) Optimization
1471 Allow built-in functions ceil, floor, round, trunc to raise \"inexact\" exceptions.
1473 ; Nonzero means don't put addresses of constant functions in registers.
1474 ; Used for compiling the Unix kernel, where strange substitutions are
1475 ; done on the assembly output.
1476 ffunction-cse
1477 Common Report Var(flag_no_function_cse,0) Optimization
1478 Allow function addresses to be held in registers.
1480 ffunction-sections
1481 Common Report Var(flag_function_sections)
1482 Place each function into its own section.
1484 fgcse
1485 Common Report Var(flag_gcse) Optimization
1486 Perform global common subexpression elimination.
1488 fgcse-lm
1489 Common Report Var(flag_gcse_lm) Init(1) Optimization
1490 Perform enhanced load motion during global common subexpression elimination.
1492 fgcse-sm
1493 Common Report Var(flag_gcse_sm) Init(0) Optimization
1494 Perform store motion after global common subexpression elimination.
1496 fgcse-las
1497 Common Report Var(flag_gcse_las) Init(0) Optimization
1498 Perform redundant load after store elimination in global common subexpression
1499 elimination.
1501 fgcse-after-reload
1502 Common Report Var(flag_gcse_after_reload) Optimization
1503 Perform global common subexpression elimination after register allocation has
1504 finished.
1506 Enum
1507 Name(dwarf_gnat_encodings) Type(int)
1509 EnumValue
1510 Enum(dwarf_gnat_encodings) String(all) Value(DWARF_GNAT_ENCODINGS_ALL)
1512 EnumValue
1513 Enum(dwarf_gnat_encodings) String(gdb) Value(DWARF_GNAT_ENCODINGS_GDB)
1515 EnumValue
1516 Enum(dwarf_gnat_encodings) String(minimal) Value(DWARF_GNAT_ENCODINGS_MINIMAL)
1518 fgnat-encodings=
1519 Common Enum(dwarf_gnat_encodings) Joined RejectNegative Report Undocumented Var(gnat_encodings)
1520 -fgnat-encodings=[all|gdb|minimal]      Select the balance between GNAT encodings and standard DWARF emitted in the debug information
1522 ; This option is not documented yet as its semantics will change.
1523 fgraphite
1524 Common Report Var(flag_graphite) Optimization
1525 Enable in and out of Graphite representation.
1527 fgraphite-identity
1528 Common Report Var(flag_graphite_identity) Optimization
1529 Enable Graphite Identity transformation.
1531 fhoist-adjacent-loads
1532 Common Report Var(flag_hoist_adjacent_loads) Optimization
1533 Enable hoisting adjacent loads to encourage generating conditional move
1534 instructions.
1536 fkeep-gc-roots-live
1537 Common Undocumented Report Var(flag_keep_gc_roots_live) Optimization
1538 ; Always keep a pointer to a live memory block
1540 floop-parallelize-all
1541 Common Report Var(flag_loop_parallelize_all) Optimization
1542 Mark all loops as parallel.
1544 floop-strip-mine
1545 Common Alias(floop-nest-optimize)
1546 Enable loop nest transforms.  Same as -floop-nest-optimize.
1548 floop-interchange
1549 Common Report Var(flag_loop_interchange) Optimization
1550 Enable loop interchange on trees.
1552 floop-block
1553 Common Alias(floop-nest-optimize)
1554 Enable loop nest transforms.  Same as -floop-nest-optimize.
1556 floop-unroll-and-jam
1557 Common Report Var(flag_unroll_jam) Optimization
1558 Perform unroll-and-jam on loops.
1560 fgnu-tm
1561 Common Report Var(flag_tm)
1562 Enable support for GNU transactional memory.
1564 fgnu-unique
1565 Common Report Var(flag_gnu_unique) Init(1)
1566 Use STB_GNU_UNIQUE if supported by the assembler.
1568 floop-flatten
1569 Common Ignore
1570 Does nothing. Preserved for backward compatibility.
1572 floop-nest-optimize
1573 Common Report Var(flag_loop_nest_optimize) Optimization
1574 Enable the loop nest optimizer.
1576 fstrict-volatile-bitfields
1577 Common Report Var(flag_strict_volatile_bitfields) Init(-1) Optimization
1578 Force bitfield accesses to match their type width.
1580 fstore-merging
1581 Common Report Var(flag_store_merging) Optimization
1582 Merge adjacent stores.
1584 fguess-branch-probability
1585 Common Report Var(flag_guess_branch_prob) Optimization
1586 Enable guessing of branch probabilities.
1588 ; Nonzero means ignore `#ident' directives.  0 means handle them.
1589 ; Generate position-independent code for executables if possible
1590 ; On SVR4 targets, it also controls whether or not to emit a
1591 ; string identifying the compiler.
1592 fident
1593 Common Report Var(flag_no_ident,0)
1594 Process #ident directives.
1596 fif-conversion
1597 Common Report Var(flag_if_conversion) Optimization
1598 Perform conversion of conditional jumps to branchless equivalents.
1600 fif-conversion2
1601 Common Report Var(flag_if_conversion2) Optimization
1602 Perform conversion of conditional jumps to conditional execution.
1604 fstack-reuse=
1605 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL) Optimization
1606 -fstack-reuse=[all|named_vars|none]     Set stack reuse level for local variables.
1608 Enum
1609 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1611 EnumValue
1612 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1614 EnumValue
1615 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1617 EnumValue
1618 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1620 ftree-loop-if-convert
1621 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1622 Convert conditional jumps in innermost loops to branchless equivalents.
1624 ftree-loop-if-convert-stores
1625 Common Ignore
1626 Does nothing. Preserved for backward compatibility.
1628 ; -finhibit-size-directive inhibits output of .size for ELF.
1629 ; This is used only for compiling crtstuff.c,
1630 ; and it may be extended to other effects
1631 ; needed for crtstuff.c on other systems.
1632 finhibit-size-directive
1633 Common Report Var(flag_inhibit_size_directive)
1634 Do not generate .size directives.
1636 findirect-inlining
1637 Common Report Var(flag_indirect_inlining) Optimization
1638 Perform indirect inlining.
1640 ; General flag to enable inlining.  Specifying -fno-inline will disable
1641 ; all inlining apart from always-inline functions.
1642 finline
1643 Common Report Var(flag_no_inline,0) Init(0) Optimization
1644 Enable inlining of function declared \"inline\", disabling disables all inlining.
1646 finline-small-functions
1647 Common Report Var(flag_inline_small_functions) Optimization
1648 Integrate functions into their callers when code size is known not to grow.
1650 finline-functions
1651 Common Report Var(flag_inline_functions) Optimization
1652 Integrate functions not declared \"inline\" into their callers when profitable.
1654 finline-functions-called-once
1655 Common Report Var(flag_inline_functions_called_once) Optimization
1656 Integrate functions only required by their single caller.
1658 finline-limit-
1659 Common RejectNegative Joined Alias(finline-limit=)
1661 finline-limit=
1662 Common RejectNegative Joined UInteger
1663 -finline-limit=<number> Limit the size of inlined functions to <number>.
1665 finline-atomics
1666 Common Report Var(flag_inline_atomics) Init(1) Optimization
1667 Inline __atomic operations when a lock free instruction sequence is available.
1669 fcf-protection
1670 Common RejectNegative Alias(fcf-protection=,full)
1672 fcf-protection=
1673 Common Report Joined RejectNegative Enum(cf_protection_level) Var(flag_cf_protection) Init(CF_NONE)
1674 -fcf-protection=[full|branch|return|none]       Instrument functions with checks to verify jump/call/return control-flow transfer
1675 instructions have valid targets.
1677 Enum
1678 Name(cf_protection_level) Type(enum cf_protection_level) UnknownError(unknown Control-Flow Protection Level %qs)
1680 EnumValue
1681 Enum(cf_protection_level) String(full) Value(CF_FULL)
1683 EnumValue
1684 Enum(cf_protection_level) String(branch) Value(CF_BRANCH)
1686 EnumValue
1687 Enum(cf_protection_level) String(return) Value(CF_RETURN)
1689 EnumValue
1690 Enum(cf_protection_level) String(none) Value(CF_NONE)
1692 finstrument-functions
1693 Common Report Var(flag_instrument_function_entry_exit)
1694 Instrument function entry and exit with profiling calls.
1696 finstrument-functions-exclude-function-list=
1697 Common RejectNegative Joined
1698 -finstrument-functions-exclude-function-list=name,...  Do not instrument listed functions.
1700 finstrument-functions-exclude-file-list=
1701 Common RejectNegative Joined
1702 -finstrument-functions-exclude-file-list=filename,...  Do not instrument functions listed in files.
1704 fipa-cp
1705 Common Report Var(flag_ipa_cp) Optimization
1706 Perform interprocedural constant propagation.
1708 fipa-cp-clone
1709 Common Report Var(flag_ipa_cp_clone) Optimization
1710 Perform cloning to make Interprocedural constant propagation stronger.
1712 fipa-cp-alignment
1713 Common Ignore
1714 Does nothing.  Preserved for backward compatibility.
1716 fipa-bit-cp
1717 Common Report Var(flag_ipa_bit_cp) Optimization
1718 Perform interprocedural bitwise constant propagation.
1720 fipa-profile
1721 Common Report Var(flag_ipa_profile) Init(0) Optimization
1722 Perform interprocedural profile propagation.
1724 fipa-pta
1725 Common Report Var(flag_ipa_pta) Init(0) Optimization
1726 Perform interprocedural points-to analysis.
1728 fipa-pure-const
1729 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1730 Discover pure and const functions.
1732 fipa-icf
1733 Common Report Var(flag_ipa_icf) Optimization
1734 Perform Identical Code Folding for functions and read-only variables.
1736 fipa-icf-functions
1737 Common Report Var(flag_ipa_icf_functions) Optimization
1738 Perform Identical Code Folding for functions.
1740 fipa-icf-variables
1741 Common Report Var(flag_ipa_icf_variables) Optimization
1742 Perform Identical Code Folding for variables.
1744 fipa-reference
1745 Common Report Var(flag_ipa_reference) Init(0) Optimization
1746 Discover read-only and non addressable static variables.
1748 fipa-reference-addressable
1749 Common Report Var(flag_ipa_reference_addressable) Init(0) Optimization
1750 Discover read-only, write-only and non-addressable static variables.
1752 fipa-stack-alignment
1753 Common Report Var(flag_ipa_stack_alignment) Init(1) Optimization
1754 Reduce stack alignment on call sites if possible.
1756 fipa-matrix-reorg
1757 Common Ignore
1758 Does nothing. Preserved for backward compatibility.
1760 fipa-struct-reorg
1761 Common Ignore
1762 Does nothing. Preserved for backward compatibility.
1764 fipa-vrp
1765 Common Report Var(flag_ipa_vrp) Optimization
1766 Perform IPA Value Range Propagation.
1768 fira-algorithm=
1769 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB) Optimization
1770 -fira-algorithm=[CB|priority]   Set the used IRA algorithm.
1772 Enum
1773 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1775 EnumValue
1776 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1778 EnumValue
1779 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1781 fira-region=
1782 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT) Optimization
1783 -fira-region=[one|all|mixed]    Set regions for IRA.
1785 Enum
1786 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1788 EnumValue
1789 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1791 EnumValue
1792 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1794 EnumValue
1795 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1797 fira-hoist-pressure
1798 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1799 Use IRA based register pressure calculation
1800 in RTL hoist optimizations.
1802 fira-loop-pressure
1803 Common Report Var(flag_ira_loop_pressure) Optimization
1804 Use IRA based register pressure calculation
1805 in RTL loop optimizations.
1807 fira-share-save-slots
1808 Common Report Var(flag_ira_share_save_slots) Init(1) Optimization
1809 Share slots for saving different hard registers.
1811 fira-share-spill-slots
1812 Common Report Var(flag_ira_share_spill_slots) Init(1) Optimization
1813 Share stack slots for spilled pseudo-registers.
1815 fira-verbose=
1816 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1817 -fira-verbose=<number>  Control IRA's level of diagnostic messages.
1819 fivopts
1820 Common Report Var(flag_ivopts) Init(1) Optimization
1821 Optimize induction variables on trees.
1823 fjump-tables
1824 Common Var(flag_jump_tables) Init(1) Optimization
1825 Use jump tables for sufficiently large switch statements.
1827 fkeep-inline-functions
1828 Common Report Var(flag_keep_inline_functions)
1829 Generate code for functions even if they are fully inlined.
1831 fkeep-static-functions
1832 Common Report Var(flag_keep_static_functions)
1833 Generate code for static functions even if they are never called.
1835 fkeep-static-consts
1836 Common Report Var(flag_keep_static_consts) Init(1)
1837 Emit static const variables even if they are not used.
1839 fleading-underscore
1840 Common Report Var(flag_leading_underscore) Init(-1)
1841 Give external symbols a leading underscore.
1843 floop-optimize
1844 Common Ignore
1845 Does nothing.  Preserved for backward compatibility.
1847 flra-remat
1848 Common Report Var(flag_lra_remat) Optimization
1849 Do CFG-sensitive rematerialization in LRA.
1851 flto
1852 Common
1853 Enable link-time optimization.
1855 flto=
1856 Common RejectNegative Joined Var(flag_lto)
1857 Link-time optimization with number of parallel jobs or jobserver.
1859 Enum
1860 Name(lto_partition_model) Type(enum lto_partition_model) UnknownError(unknown LTO partitioning model %qs)
1862 EnumValue
1863 Enum(lto_partition_model) String(none) Value(LTO_PARTITION_NONE)
1865 EnumValue
1866 Enum(lto_partition_model) String(one) Value(LTO_PARTITION_ONE)
1868 EnumValue
1869 Enum(lto_partition_model) String(balanced) Value(LTO_PARTITION_BALANCED)
1871 EnumValue
1872 Enum(lto_partition_model) String(1to1) Value(LTO_PARTITION_1TO1)
1874 EnumValue
1875 Enum(lto_partition_model) String(max) Value(LTO_PARTITION_MAX)
1877 flto-partition=
1878 Common Joined RejectNegative Enum(lto_partition_model) Var(flag_lto_partition) Init(LTO_PARTITION_BALANCED)
1879 Specify the algorithm to partition symbols and vars at linktime.
1881 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1882 flto-compression-level=
1883 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1) IntegerRange(0, 9)
1884 -flto-compression-level=<number>        Use zlib compression level <number> for IL.
1886 flto-odr-type-merging
1887 Common Report Var(flag_lto_odr_type_mering) Init(1)
1888 Merge C++ types using One Definition Rule.
1890 flto-report
1891 Common Report Var(flag_lto_report) Init(0)
1892 Report various link-time optimization statistics.
1894 flto-report-wpa
1895 Common Report Var(flag_lto_report_wpa) Init(0)
1896 Report various link-time optimization statistics for WPA only.
1898 fmath-errno
1899 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1900 Set errno after built-in math functions.
1902 fmax-errors=
1903 Common Joined RejectNegative UInteger Var(flag_max_errors)
1904 -fmax-errors=<number>   Maximum number of errors to report.
1906 fmem-report
1907 Common Report Var(mem_report)
1908 Report on permanent memory allocation.
1910 fmem-report-wpa
1911 Common Report Var(mem_report_wpa)
1912 Report on permanent memory allocation in WPA only.
1914 ; This will attempt to merge constant section constants, if 1 only
1915 ; string constants and constants from constant pool, if 2 also constant
1916 ; variables.
1917 fmerge-all-constants
1918 Common Report Var(flag_merge_constants,2) Init(1)
1919 Attempt to merge identical constants and constant variables.
1921 fmerge-constants
1922 Common Report Var(flag_merge_constants,1)
1923 Attempt to merge identical constants across compilation units.
1925 fmerge-debug-strings
1926 Common Report Var(flag_merge_debug_strings) Init(1)
1927 Attempt to merge identical debug strings across compilation units.
1929 fmessage-length=
1930 Common RejectNegative Joined UInteger
1931 -fmessage-length=<number>       Limit diagnostics to <number> characters per line.  0 suppresses line-wrapping.
1933 fmodulo-sched
1934 Common Report Var(flag_modulo_sched) Optimization
1935 Perform SMS based modulo scheduling before the first scheduling pass.
1937 fmodulo-sched-allow-regmoves
1938 Common Report Var(flag_modulo_sched_allow_regmoves) Optimization
1939 Perform SMS based modulo scheduling with register moves allowed.
1941 fmove-loop-invariants
1942 Common Report Var(flag_move_loop_invariants) Optimization
1943 Move loop invariant computations out of loops.
1945 fdce
1946 Common Var(flag_dce) Init(1) Optimization
1947 Use the RTL dead code elimination pass.
1949 fdse
1950 Common Var(flag_dse) Init(1) Optimization
1951 Use the RTL dead store elimination pass.
1953 freschedule-modulo-scheduled-loops
1954 Common Report Var(flag_resched_modulo_sched) Optimization
1955 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling.
1957 fnon-call-exceptions
1958 Common Report Var(flag_non_call_exceptions) Optimization
1959 Support synchronous non-call exceptions.
1961 foffload=
1962 Common Driver Joined MissingArgError(options or targets missing after %qs)
1963 -foffload=<targets>=<options>  Specify offloading targets and options for them.
1965 foffload-abi=
1966 Common Joined RejectNegative Enum(offload_abi) Var(flag_offload_abi) Init(OFFLOAD_ABI_UNSET)
1967 -foffload-abi=[lp64|ilp32]     Set the ABI to use in an offload compiler.
1969 Enum
1970 Name(offload_abi) Type(enum offload_abi) UnknownError(unknown offload ABI %qs)
1972 EnumValue
1973 Enum(offload_abi) String(ilp32) Value(OFFLOAD_ABI_ILP32)
1975 EnumValue
1976 Enum(offload_abi) String(lp64) Value(OFFLOAD_ABI_LP64)
1978 fomit-frame-pointer
1979 Common Report Var(flag_omit_frame_pointer) Optimization
1980 When possible do not generate stack frames.
1982 fopt-info
1983 Common Report Var(flag_opt_info) Optimization
1984 Enable all optimization info dumps on stderr.
1986 fopt-info-
1987 Common Joined RejectNegative Var(common_deferred_options) Defer
1988 -fopt-info[-<type>=filename]    Dump compiler optimization details.
1990 fsave-optimization-record
1991 Common Report Var(flag_save_optimization_record) Optimization
1992 Write a SRCFILE.opt-record.json file detailing what optimizations were performed.
1994 foptimize-register-move
1995 Common Ignore
1996 Does nothing. Preserved for backward compatibility.
1998 foptimize-sibling-calls
1999 Common Report Var(flag_optimize_sibling_calls) Optimization
2000 Optimize sibling and tail recursive calls.
2002 fpartial-inlining
2003 Common Report Var(flag_partial_inlining) Optimization
2004 Perform partial inlining.
2006 fpre-ipa-mem-report
2007 Common Report Var(pre_ipa_mem_report)
2008 Report on memory allocation before interprocedural optimization.
2010 fpost-ipa-mem-report
2011 Common Report Var(post_ipa_mem_report)
2012 Report on memory allocation before interprocedural optimization.
2014 fpack-struct
2015 Common Report Var(flag_pack_struct) Optimization
2016 Pack structure members together without holes.
2018 fpack-struct=
2019 Common RejectNegative Joined UInteger Optimization
2020 -fpack-struct=<number>  Set initial maximum structure member alignment.
2022 fpcc-struct-return
2023 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
2024 Return small aggregates in memory, not registers.
2026 fpeel-loops
2027 Common Report Var(flag_peel_loops) Optimization
2028 Perform loop peeling.
2030 fpeephole
2031 Common Report Var(flag_no_peephole,0) Optimization
2032 Enable machine specific peephole optimizations.
2034 fpeephole2
2035 Common Report Var(flag_peephole2) Optimization
2036 Enable an RTL peephole pass before sched2.
2038 fPIC
2039 Common Report Var(flag_pic,2) Negative(fPIE) Init(-1)
2040 Generate position-independent code if possible (large mode).
2042 fPIE
2043 Common Report Var(flag_pie,2) Negative(fpic) Init(-1)
2044 Generate position-independent code for executables if possible (large mode).
2046 fpic
2047 Common Report Var(flag_pic,1) Negative(fpie) Init(-1)
2048 Generate position-independent code if possible (small mode).
2050 fpie
2051 Common Report Var(flag_pie,1) Negative(fPIC) Init(-1)
2052 Generate position-independent code for executables if possible (small mode).
2054 fplt
2055 Common Report Var(flag_plt) Init(1) Optimization
2056 Use PLT for PIC calls (-fno-plt: load the address from GOT at call site).
2058 fplugin=
2059 Common Joined RejectNegative Var(common_deferred_options) Defer
2060 Specify a plugin to load.
2062 fplugin-arg-
2063 Common Joined RejectNegative Var(common_deferred_options) Defer
2064 -fplugin-arg-<name>-<key>[=<value>]     Specify argument <key>=<value> for plugin <name>.
2066 fpredictive-commoning
2067 Common Report Var(flag_predictive_commoning) Optimization
2068 Run predictive commoning optimization.
2070 fprefetch-loop-arrays
2071 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
2072 Generate prefetch instructions, if available, for arrays in loops.
2074 fprofile
2075 Common Report Var(profile_flag)
2076 Enable basic program profiling code.
2078 fprofile-abs-path
2079 Common Report Var(profile_abs_path_flag)
2080 Generate absolute source path names for gcov.
2082 fprofile-arcs
2083 Common Report Var(profile_arc_flag)
2084 Insert arc-based program profiling code.
2086 fprofile-dir=
2087 Common Joined RejectNegative Var(profile_data_prefix)
2088 Set the top-level directory for storing the profile data.
2089 The default is 'pwd'.
2091 fprofile-correction
2092 Common Report Var(flag_profile_correction)
2093 Enable correction of flow inconsistent profile data input.
2095 fprofile-update=
2096 Common Joined RejectNegative Enum(profile_update) Var(flag_profile_update) Init(PROFILE_UPDATE_SINGLE)
2097 -fprofile-update=[single|atomic|prefer-atomic]  Set the profile update method.
2099 fprofile-filter-files=
2100 Common Joined RejectNegative Var(flag_profile_filter_files)
2101 Instrument only functions from files where names match any regular expression (separated by a semi-colon).
2103 fprofile-exclude-files=
2104 Common Joined RejectNegative Var(flag_profile_exclude_files)
2105 Instrument only functions from files where names do not match all the regular expressions (separated by a semi-colon).
2107 Enum
2108 Name(profile_update) Type(enum profile_update) UnknownError(unknown profile update method %qs)
2110 EnumValue
2111 Enum(profile_update) String(single) Value(PROFILE_UPDATE_SINGLE)
2113 EnumValue
2114 Enum(profile_update) String(atomic) Value(PROFILE_UPDATE_ATOMIC)
2116 EnumValue
2117 Enum(profile_update) String(prefer-atomic) Value(PROFILE_UPDATE_PREFER_ATOMIC)
2119 fprofile-generate
2120 Common
2121 Enable common options for generating profile info for profile feedback directed optimizations.
2123 fprofile-generate=
2124 Common Joined RejectNegative
2125 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=.
2127 fprofile-use
2128 Common Var(flag_profile_use)
2129 Enable common options for performing profile feedback directed optimizations.
2131 fprofile-use=
2132 Common Joined RejectNegative
2133 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=.
2135 fprofile-values
2136 Common Report Var(flag_profile_values)
2137 Insert code to profile values of expressions.
2139 fprofile-report
2140 Common Report Var(profile_report)
2141 Report on consistency of profile.
2143 fprofile-reorder-functions
2144 Common Report Var(flag_profile_reorder_functions)
2145 Enable function reordering that improves code placement.
2147 fpatchable-function-entry=
2148 Common Joined Optimization
2149 Insert NOP instructions at each function entry.
2151 frandom-seed
2152 Common Var(common_deferred_options) Defer
2154 frandom-seed=
2155 Common Joined RejectNegative Var(common_deferred_options) Defer
2156 -frandom-seed=<string>  Make compile reproducible using <string>.
2158 ; This switch causes the command line that was used to create an
2159 ; object file to be recorded into the object file.  The exact format
2160 ; of this recording is target and binary file format dependent.
2161 ; It is related to the -fverbose-asm switch, but that switch only
2162 ; records information in the assembler output file as comments, so
2163 ; they never reach the object file.
2164 frecord-gcc-switches
2165 Common Report Var(flag_record_gcc_switches)
2166 Record gcc command line switches in the object file.
2168 freg-struct-return
2169 Common Report Var(flag_pcc_struct_return,0) Optimization
2170 Return small aggregates in registers.
2172 fregmove
2173 Common Ignore
2174 Does nothing. Preserved for backward compatibility.
2176 flifetime-dse
2177 Common Report Var(flag_lifetime_dse,2) Init(2) Optimization
2178 Tell DSE that the storage for a C++ object is dead when the constructor
2179 starts and when the destructor finishes.
2181 flifetime-dse=
2182 Common Joined RejectNegative UInteger Var(flag_lifetime_dse) Optimization IntegerRange(0, 2)
2184 flive-range-shrinkage
2185 Common Report Var(flag_live_range_shrinkage) Init(0) Optimization
2186 Relief of register pressure through live range shrinkage.
2188 frename-registers
2189 Common Report Var(flag_rename_registers) Init(2) Optimization
2190 Perform a register renaming optimization pass.
2192 fschedule-fusion
2193 Common Report Var(flag_schedule_fusion) Init(2) Optimization
2194 Perform a target dependent instruction fusion optimization pass.
2196 freorder-blocks
2197 Common Report Var(flag_reorder_blocks) Optimization
2198 Reorder basic blocks to improve code placement.
2200 freorder-blocks-algorithm=
2201 Common Joined RejectNegative Enum(reorder_blocks_algorithm) Var(flag_reorder_blocks_algorithm) Init(REORDER_BLOCKS_ALGORITHM_SIMPLE) Optimization
2202 -freorder-blocks-algorithm=[simple|stc] Set the used basic block reordering algorithm.
2204 Enum
2205 Name(reorder_blocks_algorithm) Type(enum reorder_blocks_algorithm) UnknownError(unknown basic block reordering algorithm %qs)
2207 EnumValue
2208 Enum(reorder_blocks_algorithm) String(simple) Value(REORDER_BLOCKS_ALGORITHM_SIMPLE)
2210 EnumValue
2211 Enum(reorder_blocks_algorithm) String(stc) Value(REORDER_BLOCKS_ALGORITHM_STC)
2213 freorder-blocks-and-partition
2214 Common Report Var(flag_reorder_blocks_and_partition) Optimization
2215 Reorder basic blocks and partition into hot and cold sections.
2217 freorder-functions
2218 Common Report Var(flag_reorder_functions) Optimization
2219 Reorder functions to improve code placement.
2221 frerun-cse-after-loop
2222 Common Report Var(flag_rerun_cse_after_loop) Optimization
2223 Add a common subexpression elimination pass after loop optimizations.
2225 frerun-loop-opt
2226 Common Ignore
2227 Does nothing.  Preserved for backward compatibility.
2229 frounding-math
2230 Common Report Var(flag_rounding_math) Optimization SetByCombined
2231 Disable optimizations that assume default FP rounding behavior.
2233 fsched-interblock
2234 Common Report Var(flag_schedule_interblock) Init(1) Optimization
2235 Enable scheduling across basic blocks.
2237 fsched-pressure
2238 Common Report Var(flag_sched_pressure) Init(0) Optimization
2239 Enable register pressure sensitive insn scheduling.
2241 fsched-spec
2242 Common Report Var(flag_schedule_speculative) Init(1) Optimization
2243 Allow speculative motion of non-loads.
2245 fsched-spec-load
2246 Common Report Var(flag_schedule_speculative_load) Optimization
2247 Allow speculative motion of some loads.
2249 fsched-spec-load-dangerous
2250 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
2251 Allow speculative motion of more loads.
2253 fsched-verbose=
2254 Common RejectNegative Joined UInteger Var(sched_verbose_param) Init(1)
2255 -fsched-verbose=<number>        Set the verbosity level of the scheduler.
2257 fsched2-use-superblocks
2258 Common Report Var(flag_sched2_use_superblocks) Optimization
2259 If scheduling post reload, do superblock scheduling.
2261 fsched2-use-traces
2262 Common Ignore
2263 Does nothing.  Preserved for backward compatibility.
2265 fschedule-insns
2266 Common Report Var(flag_schedule_insns) Optimization
2267 Reschedule instructions before register allocation.
2269 fschedule-insns2
2270 Common Report Var(flag_schedule_insns_after_reload) Optimization
2271 Reschedule instructions after register allocation.
2273 ; This flag should be on when a target implements non-trivial
2274 ; scheduling hooks, maybe saving some information for its own sake.
2275 ; On IA64, for example, this is used for correct bundling.
2276 fselective-scheduling
2277 Common Report Var(flag_selective_scheduling) Optimization
2278 Schedule instructions using selective scheduling algorithm.
2280 fselective-scheduling2
2281 Common Report Var(flag_selective_scheduling2) Optimization
2282 Run selective scheduling after reload.
2284 fself-test=
2285 Common Undocumented Joined Var(flag_self_test)
2286 Run self-tests, using the given path to locate test files.
2288 fsel-sched-pipelining
2289 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
2290 Perform software pipelining of inner loops during selective scheduling.
2292 fsel-sched-pipelining-outer-loops
2293 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
2294 Perform software pipelining of outer loops during selective scheduling.
2296 fsel-sched-reschedule-pipelined
2297 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
2298 Reschedule pipelined regions without pipelining.
2300 fsemantic-interposition
2301 Common Report Var(flag_semantic_interposition) Init(1)
2302 Allow interposing function (or variables) by ones with different semantics (or initializer) respectively by dynamic linker.
2304 ; sched_stalled_insns means that insns can be moved prematurely from the queue
2305 ; of stalled insns into the ready list.
2306 fsched-stalled-insns
2307 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
2308 Allow premature scheduling of queued insns.
2310 fsched-stalled-insns=
2311 Common RejectNegative Joined UInteger Optimization
2312 -fsched-stalled-insns=<number>  Set number of queued insns that can be prematurely scheduled.
2314 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
2315 ; be examined for a dependency on a stalled insn that is candidate for
2316 ; premature removal from the queue of stalled insns into the ready list (has
2317 ; an effect only if the flag 'sched_stalled_insns' is set).
2318 fsched-stalled-insns-dep
2319 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
2320 Set dependence distance checking in premature scheduling of queued insns.
2322 fsched-stalled-insns-dep=
2323 Common RejectNegative Joined UInteger Optimization
2324 -fsched-stalled-insns-dep=<number>      Set dependence distance checking in premature scheduling of queued insns.
2326 fsched-group-heuristic
2327 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
2328 Enable the group heuristic in the scheduler.
2330 fsched-critical-path-heuristic
2331 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
2332 Enable the critical path heuristic in the scheduler.
2334 fsched-spec-insn-heuristic
2335 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
2336 Enable the speculative instruction heuristic in the scheduler.
2338 fsched-rank-heuristic
2339 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
2340 Enable the rank heuristic in the scheduler.
2342 fsched-last-insn-heuristic
2343 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
2344 Enable the last instruction heuristic in the scheduler.
2346 fsched-dep-count-heuristic
2347 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
2348 Enable the dependent count heuristic in the scheduler.
2350 fsection-anchors
2351 Common Report Var(flag_section_anchors) Optimization
2352 Access data in the same section from shared anchor points.
2354 fsee
2355 Common Ignore
2356 Does nothing.  Preserved for backward compatibility.
2358 fzee
2359 Common Ignore
2360 Does nothing.  Preserved for backward compatibility.
2362 free
2363 Common Report Var(flag_ree) Init(0)
2364 Turn on Redundant Extensions Elimination pass.
2366 fshow-column
2367 Common Report Var(flag_show_column) Init(1)
2368 Show column numbers in diagnostics, when available.  Default on.
2370 fshrink-wrap
2371 Common Report Var(flag_shrink_wrap) Optimization
2372 Emit function prologues only before parts of the function that need it,
2373 rather than at the top of the function.
2375 fshrink-wrap-separate
2376 Common Report Var(flag_shrink_wrap_separate) Init(1) Optimization
2377 Shrink-wrap parts of the prologue and epilogue separately.
2379 fsignaling-nans
2380 Common Report Var(flag_signaling_nans) Optimization SetByCombined
2381 Disable optimizations observable by IEEE signaling NaNs.
2383 fsigned-zeros
2384 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
2385 Disable floating point optimizations that ignore the IEEE signedness of zero.
2387 fsingle-precision-constant
2388 Common Report Var(flag_single_precision_constant) Optimization
2389 Convert floating point constants to single precision constants.
2391 fsplit-ivs-in-unroller
2392 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
2393 Split lifetimes of induction variables when loops are unrolled.
2395 fsplit-stack
2396 Common Report Var(flag_split_stack) Init(-1)
2397 Generate discontiguous stack frames.
2399 fsplit-wide-types
2400 Common Report Var(flag_split_wide_types) Optimization
2401 Split wide types into independent registers.
2403 fssa-backprop
2404 Common Report Var(flag_ssa_backprop) Init(1) Optimization
2405 Enable backward propagation of use properties at the SSA level.
2407 fssa-phiopt
2408 Common Report Var(flag_ssa_phiopt) Optimization
2409 Optimize conditional patterns using SSA PHI nodes.
2411 fstdarg-opt
2412 Common Report Var(flag_stdarg_opt) Init(1) Optimization
2413 Optimize amount of stdarg registers saved to stack at start of function.
2415 fvariable-expansion-in-unroller
2416 Common Report Var(flag_variable_expansion_in_unroller) Optimization
2417 Apply variable expansion when loops are unrolled.
2419 fstack-check=
2420 Common Report RejectNegative Joined Optimization
2421 -fstack-check=[no|generic|specific]     Insert stack checking code into the program.
2423 fstack-check
2424 Common Alias(fstack-check=, specific, no)
2425 Insert stack checking code into the program.  Same as -fstack-check=specific.
2427 fstack-clash-protection
2428 Common Report Var(flag_stack_clash_protection) Optimization
2429 Insert code to probe each page of stack space as it is allocated to protect
2430 from stack-clash style attacks.
2432 fstack-limit
2433 Common Var(common_deferred_options) Defer
2435 fstack-limit-register=
2436 Common RejectNegative Joined Var(common_deferred_options) Defer
2437 -fstack-limit-register=<register>       Trap if the stack goes past <register>.
2439 fstack-limit-symbol=
2440 Common RejectNegative Joined Var(common_deferred_options) Defer
2441 -fstack-limit-symbol=<name>     Trap if the stack goes past symbol <name>.
2443 fstack-protector
2444 Common Report Var(flag_stack_protect, 1) Init(-1) Optimization
2445 Use propolice as a stack protection method.
2447 fstack-protector-all
2448 Common Report RejectNegative Var(flag_stack_protect, 2) Init(-1) Optimization
2449 Use a stack protection method for every function.
2451 fstack-protector-strong
2452 Common Report RejectNegative Var(flag_stack_protect, 3) Init(-1) Optimization
2453 Use a smart stack protection method for certain functions.
2455 fstack-protector-explicit
2456 Common Report RejectNegative Var(flag_stack_protect, 4) Optimization
2457 Use stack protection method only for functions with the stack_protect attribute.
2459 fstack-usage
2460 Common RejectNegative Var(flag_stack_usage)
2461 Output stack usage information on a per-function basis.
2463 fstrength-reduce
2464 Common Ignore
2465 Does nothing.  Preserved for backward compatibility.
2467 ; Nonzero if we should do (language-dependent) alias analysis.
2468 ; Typically, this analysis will assume that expressions of certain
2469 ; types do not alias expressions of certain other types.  Only used
2470 ; if alias analysis (in general) is enabled.
2471 fstrict-aliasing
2472 Common Report Var(flag_strict_aliasing) Optimization
2473 Assume strict aliasing rules apply.
2475 fstrict-overflow
2476 Common Report
2477 Treat signed overflow as undefined.  Negated as -fwrapv -fwrapv-pointer.
2479 fsync-libcalls
2480 Common Report Var(flag_sync_libcalls) Init(1)
2481 Implement __atomic operations via libcalls to legacy __sync functions.
2483 fsyntax-only
2484 Common Report Var(flag_syntax_only)
2485 Check for syntax errors, then stop.
2487 ftest-coverage
2488 Common Report Var(flag_test_coverage)
2489 Create data files needed by \"gcov\".
2491 fthread-jumps
2492 Common Report Var(flag_thread_jumps) Optimization
2493 Perform jump threading optimizations.
2495 ftime-report
2496 Common Report Var(time_report)
2497 Report the time taken by each compiler pass.
2499 ftime-report-details
2500 Common Report Var(time_report_details)
2501 Record times taken by sub-phases separately.
2503 ftls-model=
2504 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2505 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec]      Set the default thread-local storage code generation model.
2507 Enum
2508 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2510 EnumValue
2511 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2513 EnumValue
2514 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2516 EnumValue
2517 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2519 EnumValue
2520 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2522 ftoplevel-reorder
2523 Common Report Var(flag_toplevel_reorder) Init(2)
2524 Reorder top level functions, variables, and asms.
2526 ftracer
2527 Common Report Var(flag_tracer) Optimization
2528 Perform superblock formation via tail duplication.
2530 ftrampolines
2531 Common Report Var(flag_trampolines) Init(0)
2532 For targets that normally need trampolines for nested functions, always
2533 generate them instead of using descriptors.
2535 ; Zero means that floating-point math operations cannot generate a
2536 ; (user-visible) trap.  This is the case, for example, in nonstop
2537 ; IEEE 754 arithmetic.
2538 ftrapping-math
2539 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
2540 Assume floating-point operations can trap.
2542 ftrapv
2543 Common Report Var(flag_trapv) Optimization
2544 Trap for signed overflow in addition, subtraction and multiplication.
2546 ftree-ccp
2547 Common Report Var(flag_tree_ccp) Optimization
2548 Enable SSA-CCP optimization on trees.
2550 ftree-bit-ccp
2551 Common Report Var(flag_tree_bit_ccp) Optimization
2552 Enable SSA-BIT-CCP optimization on trees.
2554 ftree-store-ccp
2555 Common Ignore
2556 Does nothing.  Preserved for backward compatibility.
2558 ftree-ch
2559 Common Report Var(flag_tree_ch) Optimization
2560 Enable loop header copying on trees.
2562 ftree-coalesce-inlined-vars
2563 Common Ignore RejectNegative
2564 Does nothing.  Preserved for backward compatibility.
2566 ftree-coalesce-vars
2567 Common Report Var(flag_tree_coalesce_vars) Optimization
2568 Enable SSA coalescing of user variables.
2570 ftree-copyrename
2571 Common Ignore
2572 Does nothing.  Preserved for backward compatibility.
2574 ftree-copy-prop
2575 Common Report Var(flag_tree_copy_prop) Optimization
2576 Enable copy propagation on trees.
2578 ftree-store-copy-prop
2579 Common Ignore
2580 Does nothing.  Preserved for backward compatibility.
2582 ftree-cselim
2583 Common Report Var(flag_tree_cselim) Init(2) Optimization
2584 Transform condition stores into unconditional ones.
2586 ftree-switch-conversion
2587 Common Report Var(flag_tree_switch_conversion) Optimization
2588 Perform conversions of switch initializations.
2590 ftree-dce
2591 Common Report Var(flag_tree_dce) Optimization
2592 Enable SSA dead code elimination optimization on trees.
2594 ftree-dominator-opts
2595 Common Report Var(flag_tree_dom) Optimization
2596 Enable dominator optimizations.
2598 ftree-tail-merge
2599 Common Report Var(flag_tree_tail_merge) Optimization
2600 Enable tail merging on trees.
2602 ftree-dse
2603 Common Report Var(flag_tree_dse) Optimization
2604 Enable dead store elimination.
2606 ftree-forwprop
2607 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2608 Enable forward propagation on trees.
2610 ftree-fre
2611 Common Report Var(flag_tree_fre) Optimization
2612 Enable Full Redundancy Elimination (FRE) on trees.
2614 foptimize-strlen
2615 Common Report Var(flag_optimize_strlen) Optimization
2616 Enable string length optimizations on trees.
2618 fisolate-erroneous-paths-dereference
2619 Common Report Var(flag_isolate_erroneous_paths_dereference) Optimization
2620 Detect paths that trigger erroneous or undefined behavior due to
2621 dereferencing a null pointer.  Isolate those paths from the main control
2622 flow and turn the statement with erroneous or undefined behavior into a trap.
2624 fisolate-erroneous-paths-attribute
2625 Common Report Var(flag_isolate_erroneous_paths_attribute) Optimization
2626 Detect paths that trigger erroneous or undefined behavior due to a null value
2627 being used in a way forbidden by a returns_nonnull or nonnull
2628 attribute.  Isolate those paths from the main control flow and turn the
2629 statement with erroneous or undefined behavior into a trap.
2631 ftree-loop-distribution
2632 Common Report Var(flag_tree_loop_distribution) Optimization
2633 Enable loop distribution on trees.
2635 ftree-loop-distribute-patterns
2636 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2637 Enable loop distribution for patterns transformed into a library call.
2639 ftree-loop-im
2640 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2641 Enable loop invariant motion on trees.
2643 ftree-loop-linear
2644 Common Alias(floop-nest-optimize)
2645 Enable loop nest transforms.  Same as -floop-nest-optimize.
2647 ftree-loop-ivcanon
2648 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2649 Create canonical induction variables in loops.
2651 ftree-loop-optimize
2652 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2653 Enable loop optimizations on tree level.
2655 ftree-parallelize-loops=
2656 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1) Optimization
2657 -ftree-parallelize-loops=<number>       Enable automatic parallelization of loops.
2659 ftree-phiprop
2660 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2661 Enable hoisting loads from conditional pointers.
2663 ftree-pre
2664 Common Report Var(flag_tree_pre) Optimization
2665 Enable SSA-PRE optimization on trees.
2667 ftree-partial-pre
2668 Common Report Var(flag_tree_partial_pre) Optimization
2669 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination.
2671 ftree-pta
2672 Common Report Var(flag_tree_pta) Optimization
2673 Perform function-local points-to analysis on trees.
2675 ftree-reassoc
2676 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2677 Enable reassociation on tree level.
2679 ftree-salias
2680 Common Ignore
2681 Does nothing.  Preserved for backward compatibility.
2683 ftree-sink
2684 Common Report Var(flag_tree_sink) Optimization
2685 Enable SSA code sinking on trees.
2687 ftree-slsr
2688 Common Report Var(flag_tree_slsr) Optimization
2689 Perform straight-line strength reduction.
2691 ftree-sra
2692 Common Report Var(flag_tree_sra) Optimization
2693 Perform scalar replacement of aggregates.
2695 ftree-ter
2696 Common Report Var(flag_tree_ter) Optimization
2697 Replace temporary expressions in the SSA->normal pass.
2699 ftree-lrs
2700 Common Report Var(flag_tree_live_range_split) Optimization
2701 Perform live range splitting during the SSA->normal pass.
2703 ftree-vrp
2704 Common Report Var(flag_tree_vrp) Init(0) Optimization
2705 Perform Value Range Propagation on trees.
2707 fsplit-paths
2708 Common Report Var(flag_split_paths) Init(0) Optimization
2709 Split paths leading to loop backedges.
2711 funconstrained-commons
2712 Common Var(flag_unconstrained_commons) Optimization
2713 Assume common declarations may be overridden with ones with a larger
2714 trailing array.
2716 funit-at-a-time
2717 Common Report Var(flag_unit_at_a_time) Init(1)
2718 Compile whole compilation unit at a time.
2720 funroll-loops
2721 Common Report Var(flag_unroll_loops) Optimization
2722 Perform loop unrolling when iteration count is known.
2724 funroll-all-loops
2725 Common Report Var(flag_unroll_all_loops) Optimization
2726 Perform loop unrolling for all loops.
2728 ; Nonzero means that loop optimizer may assume that the induction variables
2729 ; that control loops do not overflow and that the loops with nontrivial
2730 ; exit condition are not infinite
2731 funsafe-loop-optimizations
2732 Common Ignore
2733 Does nothing.  Preserved for backward compatibility.
2735 fassociative-math
2736 Common Report Var(flag_associative_math) SetByCombined Optimization
2737 Allow optimization for floating-point arithmetic which may change the
2738 result of the operation due to rounding.
2740 freciprocal-math
2741 Common Report Var(flag_reciprocal_math) SetByCombined Optimization
2742 Same as -fassociative-math for expressions which include division.
2744 ; Nonzero means that unsafe floating-point math optimizations are allowed
2745 ; for the sake of speed.  IEEE compliance is not guaranteed, and operations
2746 ; are allowed to assume that their arguments and results are "normal"
2747 ; (e.g., nonnegative for SQRT).
2748 funsafe-math-optimizations
2749 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2750 Allow math optimizations that may violate IEEE or ISO standards.
2752 funswitch-loops
2753 Common Report Var(flag_unswitch_loops) Optimization
2754 Perform loop unswitching.
2756 fsplit-loops
2757 Common Report Var(flag_split_loops) Optimization
2758 Perform loop splitting.
2760 funwind-tables
2761 Common Report Var(flag_unwind_tables) Optimization
2762 Just generate unwind tables for exception handling.
2764 fuse-ld=bfd
2765 Common Driver Negative(fuse-ld=gold)
2766 Use the bfd linker instead of the default linker.
2768 fuse-ld=gold
2769 Common Driver Negative(fuse-ld=bfd)
2770 Use the gold linker instead of the default linker.
2772 fuse-ld=lld
2773 Common Driver Negative(fuse-ld=lld)
2774 Use the lld LLVM linker instead of the default linker.
2776 fuse-linker-plugin
2777 Common Undocumented Var(flag_use_linker_plugin)
2779 ; Positive if we should track variables, negative if we should run
2780 ; the var-tracking pass only to discard debug annotations, zero if
2781 ; we're not to run it.  When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2782 ; will be set according to optimize, debug_info_level and debug_hooks
2783 ; in process_options ().
2784 fvar-tracking
2785 Common Report Var(flag_var_tracking) Init(2) PerFunction
2786 Perform variable tracking.
2788 ; Positive if we should track variables at assignments, negative if
2789 ; we should run the var-tracking pass only to discard debug
2790 ; annotations.  When flag_var_tracking_assignments ==
2791 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2792 fvar-tracking-assignments
2793 Common Report Var(flag_var_tracking_assignments) Init(2) PerFunction
2794 Perform variable tracking by annotating assignments.
2796 ; Nonzero if we should toggle flag_var_tracking_assignments after
2797 ; processing options and computing its default.  */
2798 fvar-tracking-assignments-toggle
2799 Common Report Var(flag_var_tracking_assignments_toggle) PerFunction
2800 Toggle -fvar-tracking-assignments.
2802 ; Positive if we should track uninitialized variables, negative if
2803 ; we should run the var-tracking pass only to discard debug
2804 ; annotations.  When flag_var_tracking_uninit == AUTODETECT_VALUE it
2805 ; will be set according to flag_var_tracking.
2806 fvar-tracking-uninit
2807 Common Report Var(flag_var_tracking_uninit) PerFunction
2808 Perform variable tracking and also tag variables that are uninitialized.
2810 ; Alias to enable both -ftree-loop-vectorize and -ftree-slp-vectorize.
2811 ftree-vectorize
2812 Common Report Optimization
2813 Enable vectorization on trees.
2815 ftree-vectorizer-verbose=
2816 Common Joined RejectNegative Ignore
2817 Does nothing.  Preserved for backward compatibility.
2819 ftree-loop-vectorize
2820 Common Report Var(flag_tree_loop_vectorize) Optimization EnabledBy(ftree-vectorize)
2821 Enable loop vectorization on trees.
2823 ftree-slp-vectorize
2824 Common Report Var(flag_tree_slp_vectorize) Optimization EnabledBy(ftree-vectorize)
2825 Enable basic block vectorization (SLP) on trees.
2827 fvect-cost-model=
2828 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT) Optimization
2829 -fvect-cost-model=[unlimited|dynamic|cheap]     Specifies the cost model for vectorization.
2831 fsimd-cost-model=
2832 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED) Optimization
2833 -fsimd-cost-model=[unlimited|dynamic|cheap]     Specifies the vectorization cost model for code marked with a simd directive.
2835 Enum
2836 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
2838 EnumValue
2839 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
2841 EnumValue
2842 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
2844 EnumValue
2845 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
2847 fvect-cost-model
2848 Common Alias(fvect-cost-model=,dynamic,unlimited)
2849 Enables the dynamic vectorizer cost model.  Preserved for backward compatibility.
2851 ftree-vect-loop-version
2852 Common Ignore
2853 Does nothing. Preserved for backward compatibility.
2855 ftree-scev-cprop
2856 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2857 Enable copy propagation of scalar-evolution information.
2859 ; -fverbose-asm causes extra commentary information to be produced in
2860 ; the generated assembly code (to make it more readable).  This option
2861 ; is generally only of use to those who actually need to read the
2862 ; generated assembly code (perhaps while debugging the compiler itself).
2863 ; -fno-verbose-asm, the default, causes the extra information
2864 ; to not be added and is useful when comparing two assembler files.
2865 fverbose-asm
2866 Common Report Var(flag_verbose_asm)
2867 Add extra commentary to assembler output.
2869 fvisibility=
2870 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2871 -fvisibility=[default|internal|hidden|protected]        Set the default symbol visibility.
2873 Enum
2874 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2876 EnumValue
2877 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2879 EnumValue
2880 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2882 EnumValue
2883 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2885 EnumValue
2886 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2888 fvtable-verify=
2889 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
2890 Validate vtable pointers before using them.
2892 Enum
2893 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
2895 EnumValue
2896 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
2898 EnumValue
2899 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
2901 EnumValue
2902 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
2904 fvtv-counts
2905 Common Var(flag_vtv_counts)
2906 Output vtable verification counters.
2908 fvtv-debug
2909 Common Var(flag_vtv_debug)
2910 Output vtable verification pointer sets information.
2912 fvpt
2913 Common Report Var(flag_value_profile_transformations) Optimization
2914 Use expression value profiles in optimizations.
2916 fweb
2917 Common Report Var(flag_web) Init(2) Optimization
2918 Construct webs and split unrelated uses of single variable.
2920 ftree-builtin-call-dce
2921 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2922 Enable conditional dead code elimination for builtin calls.
2924 fwhole-program
2925 Common Report Var(flag_whole_program) Init(0)
2926 Perform whole program optimizations.
2928 fwrapv-pointer
2929 Common Report Var(flag_wrapv_pointer) Optimization
2930 Assume pointer overflow wraps around.
2932 fwrapv
2933 Common Report Var(flag_wrapv) Optimization
2934 Assume signed arithmetic overflow wraps around.
2936 fzero-initialized-in-bss
2937 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2938 Put zero initialized data in the bss section.
2941 Common Driver RejectNegative JoinedOrMissing
2942 Generate debug information in default format.
2944 gas-loc-support
2945 Common Driver Var(dwarf2out_as_loc_support) Init(2)
2946 Assume assembler support for (DWARF2+) .loc directives
2948 gas-locview-support
2949 Common Driver Var(dwarf2out_as_locview_support) Init(2)
2950 Assume assembler support for view in (DWARF2+) .loc directives
2952 gcoff
2953 Common Driver Deprecated
2954 Does nothing.  Preserved for backward compatibility.
2956 gcoff1
2957 Common Driver Deprecated
2958 Does nothing.  Preserved for backward compatibility.
2960 gcoff2
2961 Common Driver Deprecated
2962 Does nothing.  Preserved for backward compatibility.
2964 gcoff3
2965 Common Driver Deprecated
2966 Does nothing.  Preserved for backward compatibility.
2968 gcolumn-info
2969 Common Driver Var(debug_column_info,1) Init(1)
2970 Record DW_AT_decl_column and DW_AT_call_column in DWARF.
2972 gdwarf
2973 Common Driver JoinedOrMissing Negative(gdwarf-)
2974 Generate debug information in default version of DWARF format.
2976 gdwarf-
2977 Common Driver Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2978 Generate debug information in DWARF v2 (or later) format.
2980 ggdb
2981 Common Driver JoinedOrMissing
2982 Generate debug information in default extended format.
2984 ginline-points
2985 Common Driver Var(debug_inline_points) Init(2)
2986 Generate extended entry point information for inlined functions
2988 ginternal-reset-location-views
2989 Common Driver Var(debug_internal_reset_location_views) Init(2)
2990 Compute locview reset points based on insn length estimates
2992 gno-
2993 RejectNegative Joined Undocumented
2994 ; Catch the gno- prefix, so it doesn't backtrack to g<level>.
2996 gno-pubnames
2997 Common Driver Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
2998 Don't generate DWARF pubnames and pubtypes sections.
3000 gpubnames
3001 Common Driver Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
3002 Generate DWARF pubnames and pubtypes sections.
3004 ggnu-pubnames
3005 Common Driver Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
3006 Generate DWARF pubnames and pubtypes sections with GNU extensions.
3008 grecord-gcc-switches
3009 Common Driver Var(dwarf_record_gcc_switches) Init(1)
3010 Record gcc command line switches in DWARF DW_AT_producer.
3012 gsplit-dwarf
3013 Common Driver Var(dwarf_split_debug_info) Init(0)
3014 Generate debug information in separate .dwo files.
3016 gstabs
3017 Common Driver JoinedOrMissing Negative(gstabs+)
3018 Generate debug information in STABS format.
3020 gstabs+
3021 Common Driver JoinedOrMissing Negative(gvms)
3022 Generate debug information in extended STABS format.
3024 gstatement-frontiers
3025 Common Driver Var(debug_nonbind_markers_p) Init(2)
3026 Emit progressive recommended breakpoint locations.
3028 gstrict-dwarf
3029 Common Driver Report Var(dwarf_strict) Init(0)
3030 Don't emit DWARF additions beyond selected version.
3032 gdescribe-dies
3033 Common Driver Report Var(flag_describe_dies) Init(0)
3034 Add description attributes to some DWARF DIEs that have no name attribute.
3036 gtoggle
3037 Common Driver Report Var(flag_gtoggle)
3038 Toggle debug information generation.
3040 gvariable-location-views
3041 Common Driver Var(debug_variable_location_views, 1) Init(2)
3042 Augment variable location lists with progressive views.
3044 gvariable-location-views=incompat5
3045 Common Driver RejectNegative Var(debug_variable_location_views, -1) Init(2)
3047 gvms
3048 Common Driver JoinedOrMissing Negative(gxcoff)
3049 Generate debug information in VMS format.
3051 gxcoff
3052 Common Driver JoinedOrMissing Negative(gxcoff+)
3053 Generate debug information in XCOFF format.
3055 gxcoff+
3056 Common Driver JoinedOrMissing Negative(gdwarf)
3057 Generate debug information in extended XCOFF format.
3059 Enum
3060 Name(compressed_debug_sections) Type(int)
3062 ; Since -gz= is completely handled in specs, the values aren't used and we
3063 ; assign arbitrary constants.
3064 EnumValue
3065 Enum(compressed_debug_sections) String(none) Value(0)
3067 EnumValue
3068 Enum(compressed_debug_sections) String(zlib) Value(1)
3070 EnumValue
3071 Enum(compressed_debug_sections) String(zlib-gnu) Value(2)
3074 Common Driver
3075 Generate compressed debug sections.
3078 Common Driver RejectNegative Joined Enum(compressed_debug_sections)
3079 -gz=<format>    Generate compressed debug sections in format <format>.
3082 Driver Joined Separate
3084 iplugindir=
3085 Common Joined Var(plugindir_string) Init(0)
3086 -iplugindir=<dir>       Set <dir> to be the default plugin directory.
3088 imultiarch
3089 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
3090 -imultiarch <dir>       Set <dir> to be the multiarch include subdirectory.
3093 Driver Joined Separate
3096 Driver
3098 no-canonical-prefixes
3099 Driver
3101 nodefaultlibs
3102 Driver
3104 nostartfiles
3105 Driver
3107 nolibc
3108 Driver
3110 nostdlib
3111 Driver
3114 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
3115 -o <file>       Place output into <file>.
3118 Common Var(profile_flag)
3119 Enable function profiling.
3121 pass-exit-codes
3122 Driver Var(pass_exit_codes)
3124 pedantic
3125 Common Alias(Wpedantic)
3127 pedantic-errors
3128 Common Var(flag_pedantic_errors)
3129 Like -pedantic but issue them as errors.
3132 Driver
3134 pipe
3135 Driver Var(use_pipes)
3137 print-file-name=
3138 Driver JoinedOrMissing Var(print_file_name)
3140 print-libgcc-file-name
3141 Driver
3143 print-multi-directory
3144 Driver Var(print_multi_directory)
3146 print-multi-lib
3147 Driver Var(print_multi_lib)
3149 print-multi-os-directory
3150 Driver Var(print_multi_os_directory)
3152 print-multiarch
3153 Driver Var(print_multiarch)
3155 print-prog-name=
3156 Driver JoinedOrMissing Var(print_prog_name)
3158 print-search-dirs
3159 Driver Var(print_search_dirs)
3161 print-sysroot
3162 Driver Var(print_sysroot)
3164 print-sysroot-headers-suffix
3165 Driver Var(print_sysroot_headers_suffix)
3167 quiet
3168 Common Var(quiet_flag) RejectDriver
3169 Do not display functions compiled or elapsed time.
3172 Driver
3175 Driver
3177 save-temps
3178 Driver
3180 save-temps=
3181 Driver Joined
3184 Driver
3186 time
3187 Driver Var(report_times)
3189 time=
3190 Driver JoinedOrMissing
3193 Driver Joined Separate
3195 undef
3196 Driver
3197 ; C option, but driver must not handle as "-u ndef".
3200 Common Driver Var(verbose_flag)
3201 Enable verbose output.
3203 version
3204 Common Var(version_flag) RejectDriver
3205 Display the compiler's version.
3208 Common Var(inhibit_warnings)
3209 Suppress warnings.
3211 wrapper
3212 Driver Separate Var(wrapper_string)
3215 Driver Joined Separate
3217 shared
3218 Driver RejectNegative Negative(static-pie)
3219 Create a shared library.
3221 shared-libgcc
3222 Driver
3224 specs
3225 Driver Separate Alias(specs=)
3227 specs=
3228 Driver Joined
3230 static
3231 Driver
3233 static-libgcc
3234 Driver
3236 static-libgfortran
3237 Driver
3238 ; Documented for Fortran, but always accepted by driver.
3240 static-libstdc++
3241 Driver
3243 static-libgo
3244 Driver
3245 ; Documented for Go, but always accepted by driver.
3247 static-libasan
3248 Driver
3250 static-libtsan
3251 Driver
3253 static-liblsan
3254 Driver
3256 static-libubsan
3257 Driver
3259 symbolic
3260 Driver
3262 no-pie
3263 Driver RejectNegative Negative(shared)
3264 Don't create a dynamically linked position independent executable.
3267 Driver RejectNegative Negative(no-pie)
3268 Create a dynamically linked position independent executable.
3270 static-pie
3271 Driver RejectNegative Negative(pie)
3272 Create a static position independent executable.
3275 Driver Joined Separate
3277 fipa-ra
3278 Common Report Var(flag_ipa_ra) Optimization
3279 Use caller save register across calls if possible.
3281 ; This comment is to ensure we retain the blank line above.