1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003-2015 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
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
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.
37 ; Not used directly to control optimizations, only to save -Ofast
38 ; setting for "optimize" attributes.
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.
49 ; 0 means straightforward implementation of complex divide acceptable.
50 ; 1 means wide ranges of inputs must work for complex divide.
51 ; 2 means C99-like requirements for complex multiply and divide.
53 int flag_complex_method = 1
55 ; Nonzero if subexpressions must be evaluated from left-to-right.
57 int flag_evaluation_order = 0
59 ; Language specific warning pass for unused results.
61 bool flag_warn_unused_result = false
66 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
70 ; Nonzero if we should write GIMPLE bytecode for offload compilation.
72 int flag_generate_offload = 0
74 ; True to warn about any objects definitions whose size is larger
75 ; than N bytes. Also want about function definitions whose returned
76 ; values are larger than N bytes, where N is 'larger_than_size'.
81 HOST_WIDE_INT larger_than_size
83 ; True to warn about any function whose frame size is larger
86 bool warn_frame_larger_than
89 HOST_WIDE_INT frame_larger_than_size
91 ; Nonzero means we should be saving declaration info into a .X file.
93 int flag_gen_aux_info = 0
95 ; Nonzero if we are compiling code for a shared library, zero for
100 ; These two are really VEC(char_p,heap) *.
103 void *flag_instrument_functions_exclude_functions
106 void *flag_instrument_functions_exclude_files
108 ; Generic structs (e.g. templates not explicitly specialized)
109 ; may not have a compilation unit associated with them, and so
110 ; may need to be treated differently from ordinary structs.
112 ; Structs only handled by reference (indirectly), will also usually
113 ; not need as much debugging information.
116 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
119 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
121 ; True if we should exit after parsing options.
123 bool exit_after_options
125 ; Type(s) of debugging information we are producing (if any). See
126 ; flag-types.h for the definitions of the different possible types of
127 ; debugging information.
129 enum debug_info_type write_symbols = NO_DEBUG
131 ; Level of debugging information we are producing. See flag-types.h
132 ; for the definitions of the different possible levels.
134 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
136 ; Nonzero means use GNU-only extensions in the generated symbolic
137 ; debugging information. Currently, this only has an effect when
138 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
140 bool use_gnu_debug_info_extensions
142 ; Original value of maximum field alignment in bytes, specified via
143 ; -fpack-struct=<value>.
145 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
147 ; Type of stack check.
149 enum stack_check_type flag_stack_check = NO_STACK_CHECK
151 ; True if stack usage information needs to be computed.
153 bool flag_stack_usage_info = false
155 ; -dA causes debug commentary information to be produced in
156 ; the generated assembly code (to make it more readable). This option
157 ; is generally only of use to those who actually need to read the
158 ; generated assembly code (perhaps while debugging the compiler itself).
159 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
160 ; to be a catchall for printing debug information in the assembler file.
164 ; -dP causes the rtl to be emitted as a comment in assembly.
166 int flag_dump_rtl_in_asm
168 ; Whether -da was passed (used only in handle_common_deferred_options).
170 bool flag_dump_all_passed
172 ; Other flags saying which kinds of debugging dump have been requested.
175 int rtl_dump_and_exit
178 int flag_print_asm_name
180 ; Name of top-level original source file (what was input to cpp).
181 ; This comes from the #-command at the beginning of the actual input.
182 ; If there isn't any there, then this is the cc1 input file name.
184 const char *main_input_filename
186 ; Pointer to base name in main_input_filename, with directories and a
187 ; single final extension removed, and the length of this base
191 const char *main_input_basename
194 int main_input_baselength
196 ; Which options have been printed by --help.
200 ; Which enums have been printed by --help. 0 = not printed, no
201 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
204 char *help_enum_printed
206 ; The number of columns for --help output.
208 unsigned int help_columns
210 ; Whether this options structure has been through finish_options
212 bool flag_opts_finished
214 ; What the sanitizer should instrument
216 unsigned int flag_sanitize
218 ; What sanitizers should recover from errors
220 unsigned int flag_sanitize_recover = SANITIZE_UNDEFINED | SANITIZE_NONDEFAULT | SANITIZE_KERNEL_ADDRESS
222 ; Flag whether a prefix has been added to dump_base_name
224 bool dump_base_name_prefixed = false
236 Driver Alias(coverage)
242 Common Separate Alias(d)
245 Common Joined Alias(d)
248 Common Separate Alias(dumpbase)
251 Common Separate Alias(dumpdir)
254 Driver Separate Alias(e)
257 Driver Joined Alias(e)
260 Common Warning Alias(Wextra)
263 Driver Separate Alias(Xassembler)
266 Driver JoinedOrMissing Alias(Xassembler)
269 Driver Separate Alias(Xlinker)
272 Driver JoinedOrMissing Alias(Xlinker)
275 Driver Separate Alias(u)
278 Driver Joined Alias(u)
281 Common Driver Var(help_flag)
282 Display this information
285 Common Driver Report Joined
286 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params
289 Driver Separate Alias(x)
292 Driver Joined Alias(x)
295 Driver Separate Alias(L)
298 Driver Joined Alias(L)
300 -no-canonical-prefixes
301 Driver Alias(no-canonical-prefixes)
303 -no-standard-libraries
304 Driver Alias(nostdlib)
307 Driver Var(no_sysroot_suffix)
316 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
319 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
322 Driver Alias(pass-exit-codes)
325 Common Alias(Wpedantic)
328 Common Alias(pedantic-errors)
337 Driver Separate Alias(B)
340 Driver JoinedOrMissing Alias(B)
346 Driver Separate Alias(print-file-name=)
349 Driver JoinedOrMissing Alias(print-file-name=)
351 -print-libgcc-file-name
352 Driver Alias(print-libgcc-file-name)
354 -print-multi-directory
355 Driver Alias(print-multi-directory)
358 Driver Alias(print-multi-lib)
360 -print-multi-os-directory
361 Driver Alias(print-multi-os-directory)
364 Driver Alias(print-multiarch)
367 Driver Separate Alias(print-prog-name=)
370 Driver JoinedOrMissing Alias(print-prog-name=)
373 Driver Alias(print-search-dirs)
376 Driver Alias(print-sysroot)
378 -print-sysroot-headers-suffix
379 Driver Alias(print-sysroot-headers-suffix)
385 Driver Alias(save-temps)
391 Driver Separate Alias(specs=)
394 Driver Joined Alias(specs=)
400 Driver Alias(symbolic)
404 Alias for --help=target
412 ;; The driver used to convert options such as --help into forms such
413 ;; as -fhelp; the following four entries are for compatibility with
414 ;; any direct uses of those (undocumented) -f forms
416 Common Driver Alias(-help)
419 Common Driver Joined Alias(-help=)
422 Common Driver Alias(-target-help)
425 Common Driver Alias(-version)
429 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
432 Common Joined Alias(-param)
435 Driver Separate Alias(-sysroot=)
438 Driver JoinedOrMissing
444 Driver Joined Separate
450 Driver Joined Separate
456 Common JoinedOrMissing Optimization
457 -O<number> Set optimization level to <number>
461 Optimize for space rather than speed
465 Optimize for speed disregarding exact standards compliance
469 Optimize for debugging experience rather than speed or size
481 Driver Joined Separate
487 Driver Joined Separate
508 Common RejectNegative Warning Alias(Wextra)
509 This switch is deprecated; use -Wextra instead
512 Driver JoinedOrMissing
515 Driver JoinedOrMissing
518 Driver JoinedOrMissing
521 Common Var(warn_aggregate_return) Warning
522 Warn about returning structures, unions or arrays
524 Waggressive-loop-optimizations
525 Common Var(warn_aggressive_loop_optimizations) Init(1) Warning
526 Warn if a loop with constant number of iterations triggers undefined behavior
529 Common Var(warn_array_bounds) Warning
530 Warn if an array is accessed out of bounds
533 Common Joined RejectNegative UInteger Var(warn_array_bounds) Warning
534 Warn if an array is accessed out of bounds
537 Common Var(warn_attributes) Init(1) Warning
538 Warn about inappropriate attribute usage
541 Common Var(warn_cast_align) Warning
542 Warn about pointer casts which increase alignment
545 Common Var(warn_cpp) Init(1) Warning
546 Warn when a #warning directive is encountered
548 Wdeprecated-declarations
549 Common Var(warn_deprecated_decl) Init(1) Warning
550 Warn about uses of __attribute__((deprecated)) declarations
552 Wdisabled-optimization
553 Common Var(warn_disabled_optimization) Warning
554 Warn when an optimization pass is disabled
557 Common Var(warnings_are_errors)
558 Treat all warnings as errors
562 Treat specified warning as error
565 Common Var(extra_warnings) Warning
566 Print extra (possibly unwanted) warnings
569 Common Var(flag_fatal_errors)
570 Exit on the first error occurred
573 Common RejectNegative Joined UInteger
574 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
577 Common Var(warn_free_nonheap_object) Init(1) Warning
578 Warn when attempting to free a non-heap object
581 Common Var(warn_inline) Warning
582 Warn when an inlined function cannot be inlined
584 Winvalid-memory-model
585 Common Var(warn_invalid_memory_model) Init(1) Warning
586 Warn when an atomic memory model parameter is known to be outside the valid range.
589 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
592 Common RejectNegative Joined UInteger Warning
593 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
595 Wunsafe-loop-optimizations
596 Common Var(warn_unsafe_loop_optimizations) Warning
597 Warn if the loop cannot be optimized due to nontrivial assumptions.
600 Common Alias(Wsuggest-attribute=noreturn)
603 Common Var(warn_odr_violations) Init(1) Warning
604 Warn about some C++ One Definition Rule violations during link time optimization
607 Common Var(warn_overflow) Init(1) Warning
608 Warn about overflow in arithmetic expressions
611 Common Var(warn_packed) Warning
612 Warn when the packed attribute has no effect on struct layout
615 Common Var(warn_padded) Warning
616 Warn when padding is required to align structure members
619 Common Var(pedantic) Init(0) Warning
620 Issue warnings needed for strict compliance to the standard
623 Common Var(warn_return_local_addr) Init(1) Warning
624 Warn about returning a pointer/reference to a local or temporary variable.
627 Common Var(warn_shadow) Warning
628 Warn when one local variable shadows another
631 Common Var(warn_stack_protect) Warning
632 Warn when not issuing stack smashing protection for some reason
635 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
636 Warn if stack usage might be larger than specified amount
640 Warn about code which might break strict aliasing rules
643 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
644 Warn about code which might break strict aliasing rules
648 Warn about optimizations that assume that signed overflow is undefined
651 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
652 Warn about optimizations that assume that signed overflow is undefined
654 Wsuggest-attribute=const
655 Common Var(warn_suggest_attribute_const) Warning
656 Warn about functions which might be candidates for __attribute__((const))
658 Wsuggest-attribute=pure
659 Common Var(warn_suggest_attribute_pure) Warning
660 Warn about functions which might be candidates for __attribute__((pure))
662 Wsuggest-attribute=noreturn
663 Common Var(warn_suggest_attribute_noreturn) Warning
664 Warn about functions which might be candidates for __attribute__((noreturn))
667 Common Var(warn_suggest_final_types) Warning
668 Warn about C++ polymorphic types where adding final keyword would improve code quality
670 Wsuggest-final-methods
671 Common Var(warn_suggest_final_methods) Warning
672 Warn about C++ virtual methods where adding final keyword would improve code quality
675 Common Var(warn_system_headers) Warning
676 Do not suppress warnings from system headers
679 Common Var(warn_trampolines) Warning
680 Warn whenever a trampoline is generated
683 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
684 Warn if a comparison is always true or always false due to the limited range of the data type
687 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
688 Warn about uninitialized automatic variables
691 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
692 Warn about maybe uninitialized automatic variables
696 Does nothing. Preserved for backward compatibility.
699 Common Var(warn_unused) Init(0) Warning
700 Enable all -Wunused- warnings
702 Wunused-but-set-parameter
703 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
704 Warn when a function parameter is only set, otherwise unused
706 Wunused-but-set-variable
707 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
708 Warn when a variable is only set, otherwise unused
711 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
712 Warn when a function is unused
715 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
716 Warn when a label is unused
719 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
720 Warn when a function parameter is unused
723 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
724 Warn when an expression value is unused
727 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
728 Warn when a variable is unused
731 Common Var(warn_coverage_mismatch) Init(1) Warning
732 Warn in case profiles in -fprofile-use do not match
734 Wvector-operation-performance
735 Common Var(warn_vector_operation_performance) Warning
736 Warn when a vector operation is compiled outside the SIMD
751 Common Separate Var(aux_info_file_name)
752 -aux-info <file> Emit declaration information into <file>
755 Common Joined Alias(aux-info)
758 Common Separate RejectDriver Var(aux_base_name)
761 Common Separate RejectDriver
771 -d<letters> Enable dumps from specific passes of the compiler
774 Common Separate Var(dump_base_name)
775 -dumpbase <file> Set the file basename to be used for dumps
778 Common Separate Var(dump_dir_name)
779 -dumpdir <dir> Set the directory name to be used for dumps
791 Driver Joined Separate
793 ; This option has historically been passed down to the linker by an
794 ; accident of a %{e*} spec, so ensure it continues to be passed down
795 ; as a single option. The supported option for this purpose is
796 ; -rdynamic. See PR 47390.
800 ; The version of the C++ ABI in use. The following values are allowed:
802 ; 0: The version of the ABI believed most conformant with the C++ ABI
803 ; specification. This ABI may change as bugs are discovered and fixed.
804 ; Therefore, 0 will not necessarily indicate the same ABI in different
807 ; 1: The version of the ABI first used in G++ 3.2. No longer selectable.
809 ; 2: The version of the ABI first used in G++ 3.4, and the default
812 ; 3: The version of the ABI that fixes the missing underscore
813 ; in template non-type arguments of pointer type.
815 ; 4: The version of the ABI that introduces unambiguous mangling of
816 ; vector types. First selectable in G++ 4.5.
818 ; 5: The version of the ABI that ignores attribute const/noreturn
819 ; in function pointer mangling, and corrects mangling of decltype and
820 ; function parameters used in other parameters and the return type.
821 ; First selectable in G++ 4.6.
823 ; 6: The version of the ABI that doesn't promote scoped enums to int and
824 ; changes the mangling of template argument packs, const/static_cast,
825 ; prefix ++ and --, and a class scope function used as a template
827 ; First selectable in G++ 4.7.
829 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
830 ; corrects the mangling of lambdas in default argument scope.
831 ; First selectable in G++ 4.8.
833 ; 8: The version of the ABI that corrects the substitution behavior of
834 ; function types with function-cv-qualifiers.
835 ; First selectable in G++ 4.9 and default in G++ 5
836 ; (set in c_common_post_options).
838 ; Additional positive integers will be assigned as new versions of
839 ; the ABI become the default version of the ABI.
841 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(0)
842 The version of the C++ ABI in use
844 faggressive-loop-optimizations
845 Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1)
846 Aggressively optimize loops using language constraints
849 Common Report Var(align_functions,0) Optimization UInteger
850 Align the start of functions
853 Common RejectNegative Joined UInteger Var(align_functions)
856 Common Report Var(align_jumps,0) Optimization UInteger
857 Align labels which are only reached by jumping
860 Common RejectNegative Joined UInteger Var(align_jumps)
863 Common Report Var(align_labels,0) Optimization UInteger
867 Common RejectNegative Joined UInteger Var(align_labels)
870 Common Report Var(align_loops,0) Optimization UInteger
871 Align the start of loops
874 Common RejectNegative Joined UInteger Var(align_loops)
878 Does nothing. Preserved for backward compatibility.
882 Does nothing. Preserved for backward compatibility.
884 fargument-noalias-global
886 Does nothing. Preserved for backward compatibility.
888 fargument-noalias-anything
890 Does nothing. Preserved for backward compatibility.
893 Common Driver Report Joined
894 Select what to sanitize
897 Common Joined RejectNegative Var(common_deferred_options) Defer
898 -fasan-shadow-offset=<number> Use custom shadow memory offset.
902 After diagnosing undefined behavior attempt to continue execution
906 This switch is deprecated; use -fsanitize-recover= instead
908 fsanitize-undefined-trap-on-error
909 Common Report Var(flag_sanitize_undefined_trap_on_error) Init(0)
910 Use trap instead of a library function for undefined behavior sanitization
912 fasynchronous-unwind-tables
913 Common Report Var(flag_asynchronous_unwind_tables) Optimization
914 Generate unwind tables that are exact at each instruction boundary
917 Common Report Var(flag_auto_inc_dec) Init(1) Optimization
918 Generate auto-inc/dec instructions
921 Common Report Var(flag_auto_profile)
922 Use sample profile information for call graph node weights. The default
923 profile file is fbdata.afdo in 'pwd'.
926 Common Joined RejectNegative Var(auto_profile_file)
927 Use sample profile information for call graph node weights. The profile
928 file is specified in the argument.
930 ; -fcheck-bounds causes gcc to generate array bounds checks.
931 ; For C, C++ and ObjC: defaults off.
932 ; For Java: defaults to on.
933 ; For Fortran: defaults to off.
935 Common Report Var(flag_bounds_check)
936 Generate code to check bounds before indexing arrays
939 Common Report Var(flag_branch_on_count_reg) Optimization
940 Replace add, compare, branch with branch on count register
942 fbranch-probabilities
943 Common Report Var(flag_branch_probabilities) Optimization
944 Use profiling information for branch probabilities
946 fbranch-target-load-optimize
947 Common Report Var(flag_branch_target_load_optimize) Optimization
948 Perform branch target load optimization before prologue / epilogue threading
950 fbranch-target-load-optimize2
951 Common Report Var(flag_branch_target_load_optimize2) Optimization
952 Perform branch target load optimization after prologue / epilogue threading
955 Common Report Var(flag_btr_bb_exclusive) Optimization
956 Restrict target load migration not to re-use registers in any basic block
959 Common Joined RejectNegative Var(common_deferred_options) Defer
960 -fcall-saved-<register> Mark <register> as being preserved across functions
963 Common Joined RejectNegative Var(common_deferred_options) Defer
964 -fcall-used-<register> Mark <register> as being corrupted by function calls
966 ; Nonzero for -fcaller-saves: allocate values in regs that need to
967 ; be saved across function calls, if that produces overall better code.
968 ; Optional now, so people can test it.
970 Common Report Var(flag_caller_saves) Optimization
971 Save registers around function calls
974 Common Report Var(flag_check_data_deps)
975 Compare the results of several data dependence analyzers.
978 Common Var(flag_check_new)
979 Check the return value of new in C++
981 fcombine-stack-adjustments
982 Common Report Var(flag_combine_stack_adjustments) Optimization
983 Looks for opportunities to reduce stack adjustments and stack references.
986 Common Report Var(flag_no_common,0)
987 Do not put uninitialized globals in the common section
991 ; Converted by the driver to -fcompare-debug= options.
994 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
995 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
997 fcompare-debug-second
998 Common Driver RejectNegative Var(flag_compare_debug)
999 Run only the second compilation of -fcompare-debug
1002 Common Report Var(flag_compare_elim_after_reload) Optimization
1003 Perform comparison elimination after register allocation has finished
1006 Common Var(flag_conserve_stack) Optimization
1007 Do not perform optimizations increasing noticeably stack usage
1010 Common Report Var(flag_cprop_registers) Optimization
1011 Perform a register copy-propagation optimization pass
1014 Common Report Var(flag_crossjumping) Optimization
1015 Perform cross-jumping optimization
1018 Common Report Var(flag_cse_follow_jumps) Optimization
1019 When running CSE, follow jumps to their targets
1023 Does nothing. Preserved for backward compatibility.
1026 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
1027 Omit range reduction step when performing complex division
1030 Common Report Var(flag_cx_fortran_rules) Optimization
1031 Complex multiplication and division follow Fortran rules
1034 Common Report Var(flag_data_sections)
1035 Place data items into their own section
1038 Common Report Var(common_deferred_options) Defer
1039 List all available debugging counters with their limits and counts.
1042 Common RejectNegative Joined Var(common_deferred_options) Defer
1043 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
1046 Common Joined RejectNegative Var(common_deferred_options) Defer
1047 Map one directory name to another in debug information
1049 fdebug-types-section
1050 Common Report Var(flag_debug_types_section) Init(0)
1051 Output .debug_types section when using DWARF v4 debuginfo.
1053 ; Nonzero for -fdefer-pop: don't pop args after each function call
1054 ; instead save them up to pop many calls' args with one insns.
1056 Common Report Var(flag_defer_pop) Optimization
1057 Defer popping functions args from stack until later
1060 Common Report Var(flag_delayed_branch) Optimization
1061 Attempt to fill delay slots of branch instructions
1063 fdelete-dead-exceptions
1064 Common Report Var(flag_delete_dead_exceptions) Init(0) Optimization
1065 Delete dead instructions that may throw exceptions
1067 fdelete-null-pointer-checks
1068 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
1069 Delete useless null pointer checks
1071 fdevirtualize-at-ltrans
1072 Common Report Var(flag_ltrans_devirtualize)
1073 Stream extra data to support more aggressive devirtualization in LTO local transformation mode
1075 fdevirtualize-speculatively
1076 Common Report Var(flag_devirtualize_speculatively) Optimization
1077 Perform speculative devirtualization
1080 Common Report Var(flag_devirtualize) Optimization
1081 Try to convert virtual calls to direct ones.
1083 fdiagnostics-show-location=
1084 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1085 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
1087 ; Required for these enum values.
1092 Name(diagnostic_prefixing_rule) Type(int)
1095 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1098 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1100 fdiagnostics-show-caret
1101 Common Var(flag_diagnostics_show_caret) Init(1)
1102 Show the source line with a caret indicating the column
1105 Common Alias(fdiagnostics-color=,always,never)
1109 Driver Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1110 -fdiagnostics-color=[never|always|auto] Colorize diagnostics
1112 ; Required for these enum values.
1117 Name(diagnostic_color_rule) Type(int)
1120 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1123 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1126 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1128 fdiagnostics-show-option
1129 Common Var(flag_diagnostics_show_option) Init(1)
1130 Amend appropriate diagnostic messages with the command line option that controls them
1133 Common Joined RejectNegative Var(common_deferred_options) Defer
1134 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1137 Common Joined RejectNegative Var(common_deferred_options) Defer
1138 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1141 Common Joined RejectNegative Var(common_deferred_options) Defer
1142 -fdump-<type> Dump various compiler internals to a file
1145 Driver RejectNegative
1148 Common RejectNegative Joined Var(flag_dump_final_insns)
1149 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1152 Common RejectNegative Joined Var(flag_dump_go_spec)
1153 -fdump-go-spec=filename Write all declarations to file as Go code
1156 Common Report Var(flag_dump_noaddr)
1157 Suppress output of addresses in debugging dumps
1160 Common Driver Var(flag_report_bug)
1161 Collect and dump debug information into temporary file if ICE in C/C++
1165 Common Var(flag_dump_passes) Init(0)
1166 Dump optimization passes
1169 Common Report Var(flag_dump_unnumbered)
1170 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1172 fdump-unnumbered-links
1173 Common Report Var(flag_dump_unnumbered_links)
1174 Suppress output of previous and next insn numbers in debugging dumps
1177 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1178 Enable CFI tables via GAS assembler directives.
1181 Common Report Var(flag_early_inlining) Init(1) Optimization
1182 Perform early inlining
1184 feliminate-dwarf2-dups
1185 Common Report Var(flag_eliminate_dwarf2_dups)
1186 Perform DWARF2 duplicate elimination
1189 Common Report Var(flag_ipa_sra) Init(0) Optimization
1190 Perform interprocedural reduction of aggregates
1192 feliminate-unused-debug-symbols
1193 Common Report Var(flag_debug_only_used_symbols)
1194 Perform unused symbol elimination in debug info
1196 feliminate-unused-debug-types
1197 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1198 Perform unused type elimination in debug info
1200 femit-class-debug-always
1201 Common Report Var(flag_emit_class_debug_always) Init(0)
1202 Do not suppress C++ class debug information.
1205 Common Report Var(flag_exceptions) Optimization
1206 Enable exception handling
1208 fexpensive-optimizations
1209 Common Report Var(flag_expensive_optimizations) Optimization
1210 Perform a number of minor, expensive optimizations
1213 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1214 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1217 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1220 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1223 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1229 Common Var(flag_fat_lto_objects)
1230 Output lto objects containing both the intermediate language and binary output.
1233 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1234 Assume no NaNs or infinities are generated
1237 Common Joined RejectNegative Var(common_deferred_options) Defer
1238 -ffixed-<register> Mark <register> as being unavailable to the compiler
1241 Common Report Var(flag_float_store) Optimization
1242 Don't allocate floats and doubles in extended-precision registers
1246 Does nothing. Preserved for backward compatibility.
1249 Common Report Var(flag_forward_propagate) Optimization
1250 Perform a forward propagation pass on RTL
1253 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST) Optimization
1254 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1257 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1260 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1262 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1264 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1267 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1269 ; Nonzero means don't put addresses of constant functions in registers.
1270 ; Used for compiling the Unix kernel, where strange substitutions are
1271 ; done on the assembly output.
1273 Common Report Var(flag_no_function_cse,0) Optimization
1274 Allow function addresses to be held in registers
1277 Common Report Var(flag_function_sections)
1278 Place each function into its own section
1281 Common Report Var(flag_gcse) Optimization
1282 Perform global common subexpression elimination
1285 Common Report Var(flag_gcse_lm) Init(1) Optimization
1286 Perform enhanced load motion during global common subexpression elimination
1289 Common Report Var(flag_gcse_sm) Init(0) Optimization
1290 Perform store motion after global common subexpression elimination
1293 Common Report Var(flag_gcse_las) Init(0) Optimization
1294 Perform redundant load after store elimination in global common subexpression
1298 Common Report Var(flag_gcse_after_reload) Optimization
1299 Perform global common subexpression elimination after register allocation
1302 ; This option is not documented yet as its semantics will change.
1304 Common Report Var(flag_graphite) Optimization
1305 Enable in and out of Graphite representation
1308 Common Report Var(flag_graphite_identity) Optimization
1309 Enable Graphite Identity transformation
1311 fhoist-adjacent-loads
1312 Common Report Var(flag_hoist_adjacent_loads) Optimization
1313 Enable hoisting adjacent loads to encourage generating conditional move
1316 floop-parallelize-all
1317 Common Report Var(flag_loop_parallelize_all) Optimization
1318 Mark all loops as parallel
1321 Common Report Var(flag_loop_strip_mine) Optimization
1322 Enable Loop Strip Mining transformation
1325 Common Report Var(flag_loop_interchange) Optimization
1326 Enable Loop Interchange transformation
1329 Common Report Var(flag_loop_block) Optimization
1330 Enable Loop Blocking transformation
1332 floop-unroll-and-jam
1333 Common Report Var(flag_loop_unroll_jam) Optimization
1334 Enable Loop Unroll Jam transformation
1337 Common Report Var(flag_tm)
1338 Enable support for GNU transactional memory
1341 Common Report Var(flag_gnu_unique) Init(1)
1342 Use STB_GNU_UNIQUE if supported by the assembler
1346 Does nothing. Preserved for backward compatibility.
1349 Common Report Var(flag_loop_optimize_isl) Optimization
1350 Enable the ISL based loop nest optimizer
1352 fstrict-volatile-bitfields
1353 Common Report Var(flag_strict_volatile_bitfields) Init(-1) Optimization
1354 Force bitfield accesses to match their type width
1356 fguess-branch-probability
1357 Common Report Var(flag_guess_branch_prob) Optimization
1358 Enable guessing of branch probabilities
1360 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1361 ; Generate position-independent code for executables if possible
1362 ; On SVR4 targets, it also controls whether or not to emit a
1363 ; string identifying the compiler.
1365 Common Report Var(flag_no_ident,0)
1366 Process #ident directives
1369 Common Report Var(flag_if_conversion) Optimization
1370 Perform conversion of conditional jumps to branchless equivalents
1373 Common Report Var(flag_if_conversion2) Optimization
1374 Perform conversion of conditional jumps to conditional execution
1377 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL) Optimization
1378 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1381 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1384 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1387 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1390 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1392 ftree-loop-if-convert
1393 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1394 Convert conditional jumps in innermost loops to branchless equivalents
1396 ftree-loop-if-convert-stores
1397 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1398 Also if-convert conditional jumps containing memory writes
1400 ; -finhibit-size-directive inhibits output of .size for ELF.
1401 ; This is used only for compiling crtstuff.c,
1402 ; and it may be extended to other effects
1403 ; needed for crtstuff.c on other systems.
1404 finhibit-size-directive
1405 Common Report Var(flag_inhibit_size_directive)
1406 Do not generate .size directives
1409 Common Report Var(flag_indirect_inlining) Optimization
1410 Perform indirect inlining
1412 ; General flag to enable inlining. Specifying -fno-inline will disable
1413 ; all inlining apart from always-inline functions.
1415 Common Report Var(flag_no_inline,0) Init(0) Optimization
1416 Enable inlining of function declared \"inline\", disabling disables all inlining
1418 finline-small-functions
1419 Common Report Var(flag_inline_small_functions) Optimization
1420 Integrate functions into their callers when code size is known not to grow
1423 Common Report Var(flag_inline_functions) Optimization
1424 Integrate functions not declared \"inline\" into their callers when profitable
1426 finline-functions-called-once
1427 Common Report Var(flag_inline_functions_called_once) Optimization
1428 Integrate functions only required by their single caller
1431 Common RejectNegative Joined Alias(finline-limit=)
1434 Common RejectNegative Joined UInteger
1435 -finline-limit=<number> Limit the size of inlined functions to <number>
1438 Common Report Var(flag_inline_atomics) Init(1) Optimization
1439 Inline __atomic operations when a lock free instruction sequence is available.
1441 finstrument-functions
1442 Common Report Var(flag_instrument_function_entry_exit)
1443 Instrument function entry and exit with profiling calls
1445 finstrument-functions-exclude-function-list=
1446 Common RejectNegative Joined
1447 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1449 finstrument-functions-exclude-file-list=
1450 Common RejectNegative Joined
1451 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1454 Common Report Var(flag_ipa_cp) Optimization
1455 Perform interprocedural constant propagation
1458 Common Report Var(flag_ipa_cp_clone) Optimization
1459 Perform cloning to make Interprocedural constant propagation stronger
1462 Common Report Var(flag_ipa_cp_alignment) Optimization
1463 Perform alignment discovery and propagation to make Interprocedural constant propagation stronger
1466 Common Report Var(flag_ipa_profile) Init(0) Optimization
1467 Perform interprocedural profile propagation
1470 Common Report Var(flag_ipa_pta) Init(0) Optimization
1471 Perform interprocedural points-to analysis
1474 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1475 Discover pure and const functions
1478 Common Report Var(flag_ipa_icf) Optimization
1479 Perform Identical Code Folding for functions and read-only variables
1482 Common Report Var(flag_ipa_icf_functions) Optimization
1483 Perform Identical Code Folding for functions
1486 Common Report Var(flag_ipa_icf_variables)
1487 Perform Identical Code Folding for variables
1490 Common Report Var(flag_ipa_reference) Init(0) Optimization
1491 Discover readonly and non addressable static variables
1495 Does nothing. Preserved for backward compatibility.
1499 Does nothing. Preserved for backward compatibility.
1502 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB) Optimization
1503 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1506 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1509 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1512 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1515 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT) Optimization
1516 -fira-region=[one|all|mixed] Set regions for IRA
1519 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1522 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1525 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1528 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1531 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1532 Use IRA based register pressure calculation
1533 in RTL hoist optimizations.
1536 Common Report Var(flag_ira_loop_pressure) Optimization
1537 Use IRA based register pressure calculation
1538 in RTL loop optimizations.
1540 fira-share-save-slots
1541 Common Report Var(flag_ira_share_save_slots) Init(1) Optimization
1542 Share slots for saving different hard registers.
1544 fira-share-spill-slots
1545 Common Report Var(flag_ira_share_spill_slots) Init(1) Optimization
1546 Share stack slots for spilled pseudo-registers.
1549 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1550 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1553 Common Report Var(flag_ivopts) Init(1) Optimization
1554 Optimize induction variables on trees
1557 Common Var(flag_jump_tables) Init(1) Optimization
1558 Use jump tables for sufficiently large switch statements
1560 fkeep-inline-functions
1561 Common Report Var(flag_keep_inline_functions)
1562 Generate code for functions even if they are fully inlined
1565 Common Report Var(flag_keep_static_consts) Init(1)
1566 Emit static const variables even if they are not used
1569 Common Report Var(flag_leading_underscore) Init(-1)
1570 Give external symbols a leading underscore
1574 Does nothing. Preserved for backward compatibility.
1577 Common Report Var(flag_lra_remat) Optimization
1578 Do CFG-sensitive rematerialization in LRA
1582 Enable link-time optimization.
1585 Common RejectNegative Joined Var(flag_lto)
1586 Link-time optimization with number of parallel jobs or jobserver.
1589 Name(lto_partition_model) Type(enum lto_partition_model) UnknownError(unknown LTO partitioning model %qs)
1592 Enum(lto_partition_model) String(none) Value(LTO_PARTITION_NONE)
1595 Enum(lto_partition_model) String(one) Value(LTO_PARTITION_ONE)
1598 Enum(lto_partition_model) String(balanced) Value(LTO_PARTITION_BALANCED)
1601 Enum(lto_partition_model) String(1to1) Value(LTO_PARTITION_1TO1)
1604 Enum(lto_partition_model) String(max) Value(LTO_PARTITION_MAX)
1607 Common Joined RejectNegative Enum(lto_partition_model) Var(flag_lto_partition) Init(LTO_PARTITION_BALANCED)
1608 Specify the algorithm to partition symbols and vars at linktime
1610 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1611 flto-compression-level=
1612 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1613 -flto-compression-level=<number> Use zlib compression level <number> for IL
1615 flto-odr-type-merging
1616 Common Report Var(flag_lto_odr_type_mering) Init(1)
1617 Merge C++ types using One Definition Rule
1620 Common Report Var(flag_lto_report) Init(0)
1621 Report various link-time optimization statistics
1624 Common Report Var(flag_lto_report_wpa) Init(0)
1625 Report various link-time optimization statistics for WPA only
1628 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1629 Set errno after built-in math functions
1632 Common Joined RejectNegative UInteger Var(flag_max_errors)
1633 -fmax-errors=<number> Maximum number of errors to report
1636 Common Report Var(mem_report)
1637 Report on permanent memory allocation
1640 Common Report Var(mem_report_wpa)
1641 Report on permanent memory allocation in WPA only
1643 ; This will attempt to merge constant section constants, if 1 only
1644 ; string constants and constants from constant pool, if 2 also constant
1646 fmerge-all-constants
1647 Common Report Var(flag_merge_constants,2) Init(1)
1648 Attempt to merge identical constants and constant variables
1651 Common Report Var(flag_merge_constants,1)
1652 Attempt to merge identical constants across compilation units
1654 fmerge-debug-strings
1655 Common Report Var(flag_merge_debug_strings) Init(1)
1656 Attempt to merge identical debug strings across compilation units
1659 Common RejectNegative Joined UInteger
1660 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1663 Common Report Var(flag_modulo_sched) Optimization
1664 Perform SMS based modulo scheduling before the first scheduling pass
1666 fmodulo-sched-allow-regmoves
1667 Common Report Var(flag_modulo_sched_allow_regmoves) Optimization
1668 Perform SMS based modulo scheduling with register moves allowed
1670 fmove-loop-invariants
1671 Common Report Var(flag_move_loop_invariants) Optimization
1672 Move loop invariant computations out of loops
1675 Common Var(flag_dce) Init(1) Optimization
1676 Use the RTL dead code elimination pass
1679 Common Var(flag_dse) Init(1) Optimization
1680 Use the RTL dead store elimination pass
1682 freschedule-modulo-scheduled-loops
1683 Common Report Var(flag_resched_modulo_sched) Optimization
1684 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1686 fnon-call-exceptions
1687 Common Report Var(flag_non_call_exceptions) Optimization
1688 Support synchronous non-call exceptions
1691 Common Driver Joined MissingArgError(options or targets missing after %qs)
1692 -foffload=<targets>=<options> Specify offloading targets and options for them
1695 Common Joined RejectNegative Enum(offload_abi) Var(flag_offload_abi) Init(OFFLOAD_ABI_UNSET)
1696 -foffload-abi=[lp64|ilp32] Set the ABI to use in an offload compiler
1699 Name(offload_abi) Type(enum offload_abi) UnknownError(unknown offload ABI %qs)
1702 Enum(offload_abi) String(ilp32) Value(OFFLOAD_ABI_ILP32)
1705 Enum(offload_abi) String(lp64) Value(OFFLOAD_ABI_LP64)
1708 Common Report Var(flag_omit_frame_pointer) Optimization
1709 When possible do not generate stack frames
1712 Common Report Var(flag_opt_info) Optimization
1713 Enable all optimization info dumps on stderr
1716 Common Joined RejectNegative Var(common_deferred_options) Defer
1717 -fopt-info[-<type>=filename] Dump compiler optimization details
1719 foptimize-register-move
1721 Does nothing. Preserved for backward compatibility.
1723 foptimize-sibling-calls
1724 Common Report Var(flag_optimize_sibling_calls) Optimization
1725 Optimize sibling and tail recursive calls
1728 Common Report Var(flag_partial_inlining) Optimization
1729 Perform partial inlining
1732 Common Report Var(pre_ipa_mem_report)
1733 Report on memory allocation before interprocedural optimization
1735 fpost-ipa-mem-report
1736 Common Report Var(post_ipa_mem_report)
1737 Report on memory allocation before interprocedural optimization
1740 Common Report Var(flag_pack_struct) Optimization
1741 Pack structure members together without holes
1744 Common RejectNegative Joined UInteger Optimization
1745 -fpack-struct=<number> Set initial maximum structure member alignment
1748 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1749 Return small aggregates in memory, not registers
1752 Common Report Var(flag_peel_loops) Optimization
1753 Perform loop peeling
1756 Common Report Var(flag_no_peephole,0) Optimization
1757 Enable machine specific peephole optimizations
1760 Common Report Var(flag_peephole2) Optimization
1761 Enable an RTL peephole pass before sched2
1764 Common Report Var(flag_pic,2) Negative(fPIE)
1765 Generate position-independent code if possible (large mode)
1768 Common Report Var(flag_pie,2) Negative(fpic)
1769 Generate position-independent code for executables if possible (large mode)
1772 Common Report Var(flag_pic,1) Negative(fpie)
1773 Generate position-independent code if possible (small mode)
1776 Common Report Var(flag_pie,1) Negative(fPIC)
1777 Generate position-independent code for executables if possible (small mode)
1780 Common Joined RejectNegative Var(common_deferred_options) Defer
1781 Specify a plugin to load
1784 Common Joined RejectNegative Var(common_deferred_options) Defer
1785 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1787 fpredictive-commoning
1788 Common Report Var(flag_predictive_commoning) Optimization
1789 Run predictive commoning optimization.
1791 fprefetch-loop-arrays
1792 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1793 Generate prefetch instructions, if available, for arrays in loops
1796 Common Report Var(profile_flag)
1797 Enable basic program profiling code
1800 Common Report Var(profile_arc_flag)
1801 Insert arc-based program profiling code
1804 Common Joined RejectNegative Var(profile_data_prefix)
1805 Set the top-level directory for storing the profile data.
1806 The default is 'pwd'.
1809 Common Report Var(flag_profile_correction)
1810 Enable correction of flow inconsistent profile data input
1814 Enable common options for generating profile info for profile feedback directed optimizations
1817 Common Joined RejectNegative
1818 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1821 Common Var(flag_profile_use)
1822 Enable common options for performing profile feedback directed optimizations
1825 Common Joined RejectNegative
1826 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1829 Common Report Var(flag_profile_values)
1830 Insert code to profile values of expressions
1833 Common Report Var(profile_report)
1834 Report on consistency of profile
1836 fprofile-reorder-functions
1837 Common Report Var(flag_profile_reorder_functions)
1838 Enable function reordering that improves code placement
1841 Common Var(common_deferred_options) Defer
1844 Common Joined RejectNegative Var(common_deferred_options) Defer
1845 -frandom-seed=<number> Make compile reproducible using <number>
1847 ; This switch causes the command line that was used to create an
1848 ; object file to be recorded into the object file. The exact format
1849 ; of this recording is target and binary file format dependent.
1850 ; It is related to the -fverbose-asm switch, but that switch only
1851 ; records information in the assembler output file as comments, so
1852 ; they never reach the object file.
1853 frecord-gcc-switches
1854 Common Report Var(flag_record_gcc_switches)
1855 Record gcc command line switches in the object file.
1858 Common Report Var(flag_pcc_struct_return,0) Optimization
1859 Return small aggregates in registers
1863 Does nothing. Preserved for backward compatibility.
1866 Common Report Var(flag_lifetime_dse) Init(1) Optimization
1867 Tell DSE that the storage for a C++ object is dead when the constructor
1868 starts and when the destructor finishes.
1870 flive-range-shrinkage
1871 Common Report Var(flag_live_range_shrinkage) Init(0) Optimization
1872 Relief of register pressure through live range shrinkage
1875 Common Report Var(flag_rename_registers) Init(2) Optimization
1876 Perform a register renaming optimization pass
1879 Common Report Var(flag_schedule_fusion) Init(2) Optimization
1880 Perform a target dependent instruction fusion optimization pass
1883 Common Report Var(flag_reorder_blocks) Optimization
1884 Reorder basic blocks to improve code placement
1886 freorder-blocks-and-partition
1887 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1888 Reorder basic blocks and partition into hot and cold sections
1891 Common Report Var(flag_reorder_functions) Optimization
1892 Reorder functions to improve code placement
1894 frerun-cse-after-loop
1895 Common Report Var(flag_rerun_cse_after_loop) Optimization
1896 Add a common subexpression elimination pass after loop optimizations
1900 Does nothing. Preserved for backward compatibility.
1903 Common Report Var(flag_rounding_math) Optimization SetByCombined
1904 Disable optimizations that assume default FP rounding behavior
1907 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1908 Enable scheduling across basic blocks
1911 Common Report Var(flag_sched_pressure) Init(0) Optimization
1912 Enable register pressure sensitive insn scheduling
1915 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1916 Allow speculative motion of non-loads
1919 Common Report Var(flag_schedule_speculative_load) Optimization
1920 Allow speculative motion of some loads
1922 fsched-spec-load-dangerous
1923 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1924 Allow speculative motion of more loads
1927 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1928 -fsched-verbose=<number> Set the verbosity level of the scheduler
1930 fsched2-use-superblocks
1931 Common Report Var(flag_sched2_use_superblocks) Optimization
1932 If scheduling post reload, do superblock scheduling
1936 Does nothing. Preserved for backward compatibility.
1939 Common Report Var(flag_schedule_insns) Optimization
1940 Reschedule instructions before register allocation
1943 Common Report Var(flag_schedule_insns_after_reload) Optimization
1944 Reschedule instructions after register allocation
1946 ; This flag should be on when a target implements non-trivial
1947 ; scheduling hooks, maybe saving some information for its own sake.
1948 ; On IA64, for example, this is used for correct bundling.
1949 fselective-scheduling
1950 Common Report Var(flag_selective_scheduling) Optimization
1951 Schedule instructions using selective scheduling algorithm
1953 fselective-scheduling2
1954 Common Report Var(flag_selective_scheduling2) Optimization
1955 Run selective scheduling after reload
1957 fsel-sched-pipelining
1958 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1959 Perform software pipelining of inner loops during selective scheduling
1961 fsel-sched-pipelining-outer-loops
1962 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1963 Perform software pipelining of outer loops during selective scheduling
1965 fsel-sched-reschedule-pipelined
1966 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1967 Reschedule pipelined regions without pipelining
1969 fsemantic-interposition
1970 Common Report Var(flag_semantic_interposition) Init(1)
1971 Allow interposing function (or variables) by ones with different semantics (or initializer) respectively by dynamic linker
1973 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1974 ; of stalled insns into the ready list.
1975 fsched-stalled-insns
1976 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1977 Allow premature scheduling of queued insns
1979 fsched-stalled-insns=
1980 Common RejectNegative Joined UInteger Optimization
1981 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1983 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1984 ; be examined for a dependency on a stalled insn that is candidate for
1985 ; premature removal from the queue of stalled insns into the ready list (has
1986 ; an effect only if the flag 'sched_stalled_insns' is set).
1987 fsched-stalled-insns-dep
1988 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1989 Set dependence distance checking in premature scheduling of queued insns
1991 fsched-stalled-insns-dep=
1992 Common RejectNegative Joined UInteger Optimization
1993 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1995 fsched-group-heuristic
1996 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1997 Enable the group heuristic in the scheduler
1999 fsched-critical-path-heuristic
2000 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
2001 Enable the critical path heuristic in the scheduler
2003 fsched-spec-insn-heuristic
2004 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
2005 Enable the speculative instruction heuristic in the scheduler
2007 fsched-rank-heuristic
2008 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
2009 Enable the rank heuristic in the scheduler
2011 fsched-last-insn-heuristic
2012 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
2013 Enable the last instruction heuristic in the scheduler
2015 fsched-dep-count-heuristic
2016 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
2017 Enable the dependent count heuristic in the scheduler
2020 Common Report Var(flag_section_anchors) Optimization
2021 Access data in the same section from shared anchor points
2025 Does nothing. Preserved for backward compatibility.
2029 Does nothing. Preserved for backward compatibility.
2032 Common Report Var(flag_ree) Init(0)
2033 Turn on Redundant Extensions Elimination pass.
2036 Common Report Var(flag_show_column) Init(1)
2037 Show column numbers in diagnostics, when available. Default on
2040 Common Report Var(flag_shrink_wrap) Optimization
2041 Emit function prologues only before parts of the function that need it,
2042 rather than at the top of the function.
2045 Common Report Var(flag_signaling_nans) Optimization SetByCombined
2046 Disable optimizations observable by IEEE signaling NaNs
2049 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
2050 Disable floating point optimizations that ignore the IEEE signedness of zero
2052 fsingle-precision-constant
2053 Common Report Var(flag_single_precision_constant) Optimization
2054 Convert floating point constants to single precision constants
2056 fsplit-ivs-in-unroller
2057 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
2058 Split lifetimes of induction variables when loops are unrolled
2061 Common Report Var(flag_split_stack) Init(-1)
2062 Generate discontiguous stack frames
2065 Common Report Var(flag_split_wide_types) Optimization
2066 Split wide types into independent registers
2069 Common Report Var(flag_ssa_phiopt) Optimization
2070 Optimize conditional patterns using SSA PHI nodes
2073 Common Report Var(flag_stdarg_opt) Init(1) Optimization
2074 Optimize amount of stdarg registers saved to stack at start of function
2076 fvariable-expansion-in-unroller
2077 Common Report Var(flag_variable_expansion_in_unroller) Optimization
2078 Apply variable expansion when loops are unrolled
2081 Common Report RejectNegative Joined
2082 -fstack-check=[no|generic|specific] Insert stack checking code into the program
2085 Common Alias(fstack-check=, specific, no)
2086 Insert stack checking code into the program. Same as -fstack-check=specific
2089 Common Var(common_deferred_options) Defer
2091 fstack-limit-register=
2092 Common RejectNegative Joined Var(common_deferred_options) Defer
2093 -fstack-limit-register=<register> Trap if the stack goes past <register>
2095 fstack-limit-symbol=
2096 Common RejectNegative Joined Var(common_deferred_options) Defer
2097 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
2100 Common Report Var(flag_stack_protect, 1)
2101 Use propolice as a stack protection method
2103 fstack-protector-all
2104 Common Report RejectNegative Var(flag_stack_protect, 2)
2105 Use a stack protection method for every function
2107 fstack-protector-strong
2108 Common Report RejectNegative Var(flag_stack_protect, 3)
2109 Use a smart stack protection method for certain functions
2111 fstack-protector-explicit
2112 Common Report RejectNegative Var(flag_stack_protect, 4)
2113 Use stack protection method only for functions with the stack_protect attribute
2116 Common RejectNegative Var(flag_stack_usage)
2117 Output stack usage information on a per-function basis
2121 Does nothing. Preserved for backward compatibility.
2123 ; Nonzero if we should do (language-dependent) alias analysis.
2124 ; Typically, this analysis will assume that expressions of certain
2125 ; types do not alias expressions of certain other types. Only used
2126 ; if alias analysis (in general) is enabled.
2128 Common Report Var(flag_strict_aliasing) Optimization
2129 Assume strict aliasing rules apply
2132 Common Report Var(flag_strict_overflow) Optimization
2133 Treat signed overflow as undefined
2136 Common Report Var(flag_sync_libcalls) Init(1)
2137 Implement __atomic operations via libcalls to legacy __sync functions
2140 Common Report Var(flag_syntax_only)
2141 Check for syntax errors, then stop
2144 Common Report Var(flag_test_coverage)
2145 Create data files needed by \"gcov\"
2148 Common Report Var(flag_thread_jumps) Optimization
2149 Perform jump threading optimizations
2152 Common Report Var(time_report)
2153 Report the time taken by each compiler pass
2156 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2157 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
2160 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2163 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2166 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2169 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2172 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2175 Common Report Var(flag_toplevel_reorder) Init(2)
2176 Reorder top level functions, variables, and asms
2179 Common Report Var(flag_tracer) Optimization
2180 Perform superblock formation via tail duplication
2182 ; Zero means that floating-point math operations cannot generate a
2183 ; (user-visible) trap. This is the case, for example, in nonstop
2184 ; IEEE 754 arithmetic.
2186 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
2187 Assume floating-point operations can trap
2190 Common Report Var(flag_trapv) Optimization
2191 Trap for signed overflow in addition, subtraction and multiplication
2194 Common Report Var(flag_tree_ccp) Optimization
2195 Enable SSA-CCP optimization on trees
2198 Common Report Var(flag_tree_bit_ccp) Optimization
2199 Enable SSA-BIT-CCP optimization on trees
2203 Does nothing. Preserved for backward compatibility.
2206 Common Report Var(flag_tree_ch) Optimization
2207 Enable loop header copying on trees
2209 ftree-coalesce-inlined-vars
2210 Common Report Var(flag_ssa_coalesce_vars,1) Init(2) RejectNegative Optimization
2211 Enable coalescing of copy-related user variables that are inlined
2214 Common Report Var(flag_ssa_coalesce_vars,2) Optimization
2215 Enable coalescing of all copy-related user variables
2218 Common Report Var(flag_tree_copyrename) Optimization
2219 Replace SSA temporaries with better names in copies
2222 Common Report Var(flag_tree_copy_prop) Optimization
2223 Enable copy propagation on trees
2225 ftree-store-copy-prop
2227 Does nothing. Preserved for backward compatibility.
2230 Common Report Var(flag_tree_cselim) Init(2) Optimization
2231 Transform condition stores into unconditional ones
2233 ftree-switch-conversion
2234 Common Report Var(flag_tree_switch_conversion) Optimization
2235 Perform conversions of switch initializations.
2238 Common Report Var(flag_tree_dce) Optimization
2239 Enable SSA dead code elimination optimization on trees
2241 ftree-dominator-opts
2242 Common Report Var(flag_tree_dom) Optimization
2243 Enable dominator optimizations
2246 Common Report Var(flag_tree_tail_merge) Optimization
2247 Enable tail merging on trees
2250 Common Report Var(flag_tree_dse) Optimization
2251 Enable dead store elimination
2254 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2255 Enable forward propagation on trees
2258 Common Report Var(flag_tree_fre) Optimization
2259 Enable Full Redundancy Elimination (FRE) on trees
2262 Common Report Var(flag_optimize_strlen) Optimization
2263 Enable string length optimizations on trees
2265 fisolate-erroneous-paths-dereference
2266 Common Report Var(flag_isolate_erroneous_paths_dereference) Optimization
2267 Detect paths that trigger erroneous or undefined behavior due to
2268 dereferencing a null pointer. Isolate those paths from the main control
2269 flow and turn the statement with erroneous or undefined behavior into a trap.
2271 fisolate-erroneous-paths-attribute
2272 Common Report Var(flag_isolate_erroneous_paths_attribute) Optimization
2273 Detect paths that trigger erroneous or undefined behavior due a null value
2274 being used in a way forbidden by a returns_nonnull or nonnull
2275 attribute. Isolate those paths from the main control flow and turn the
2276 statement with erroneous or undefined behavior into a trap.
2278 ftree-loop-distribution
2279 Common Report Var(flag_tree_loop_distribution) Optimization
2280 Enable loop distribution on trees
2282 ftree-loop-distribute-patterns
2283 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2284 Enable loop distribution for patterns transformed into a library call
2287 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2288 Enable loop invariant motion on trees
2291 Common Alias(floop-interchange)
2292 Enable loop interchange transforms. Same as -floop-interchange
2295 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2296 Create canonical induction variables in loops
2299 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2300 Enable loop optimizations on tree level
2302 ftree-parallelize-loops=
2303 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1) Optimization
2304 Enable automatic parallelization of loops
2307 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2308 Enable hoisting loads from conditional pointers.
2311 Common Report Var(flag_tree_pre) Optimization
2312 Enable SSA-PRE optimization on trees
2315 Common Report Var(flag_tree_partial_pre) Optimization
2316 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination
2319 Common Report Var(flag_tree_pta) Optimization
2320 Perform function-local points-to analysis on trees.
2323 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2324 Enable reassociation on tree level
2328 Does nothing. Preserved for backward compatibility.
2331 Common Report Var(flag_tree_sink) Optimization
2332 Enable SSA code sinking on trees
2335 Common Report Var(flag_tree_slsr) Optimization
2336 Perform straight-line strength reduction
2339 Common Report Var(flag_tree_sra) Optimization
2340 Perform scalar replacement of aggregates
2343 Common Report Var(flag_tree_ter) Optimization
2344 Replace temporary expressions in the SSA->normal pass
2347 Common Report Var(flag_tree_live_range_split) Optimization
2348 Perform live range splitting during the SSA->normal pass
2351 Common Report Var(flag_tree_vrp) Init(0) Optimization
2352 Perform Value Range Propagation on trees
2355 Common Report Var(flag_unit_at_a_time) Init(1)
2356 Compile whole compilation unit at a time
2359 Common Report Var(flag_unroll_loops) Optimization
2360 Perform loop unrolling when iteration count is known
2363 Common Report Var(flag_unroll_all_loops) Optimization
2364 Perform loop unrolling for all loops
2366 ; Nonzero means that loop optimizer may assume that the induction variables
2367 ; that control loops do not overflow and that the loops with nontrivial
2368 ; exit condition are not infinite
2369 funsafe-loop-optimizations
2370 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2371 Allow loop optimizations to assume that the loops behave in normal way
2374 Common Report Var(flag_associative_math) SetByCombined Optimization
2375 Allow optimization for floating-point arithmetic which may change the
2376 result of the operation due to rounding.
2379 Common Report Var(flag_reciprocal_math) SetByCombined Optimization
2380 Same as -fassociative-math for expressions which include division.
2382 ; Nonzero means that unsafe floating-point math optimizations are allowed
2383 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2384 ; are allowed to assume that their arguments and results are "normal"
2385 ; (e.g., nonnegative for SQRT).
2386 funsafe-math-optimizations
2387 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2388 Allow math optimizations that may violate IEEE or ISO standards
2391 Common Report Var(flag_unswitch_loops) Optimization
2392 Perform loop unswitching
2395 Common Report Var(flag_unwind_tables) Optimization
2396 Just generate unwind tables for exception handling
2399 Common Driver Negative(fuse-ld=gold)
2400 Use the bfd linker instead of the default linker
2403 Common Driver Negative(fuse-ld=bfd)
2404 Use the gold linker instead of the default linker
2407 Common Undocumented Var(flag_use_linker_plugin)
2409 ; Positive if we should track variables, negative if we should run
2410 ; the var-tracking pass only to discard debug annotations, zero if
2411 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2412 ; will be set according to optimize, debug_info_level and debug_hooks
2413 ; in process_options ().
2415 Common Report Var(flag_var_tracking) Init(2) Optimization
2416 Perform variable tracking
2418 ; Positive if we should track variables at assignments, negative if
2419 ; we should run the var-tracking pass only to discard debug
2420 ; annotations. When flag_var_tracking_assignments ==
2421 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2422 fvar-tracking-assignments
2423 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2424 Perform variable tracking by annotating assignments
2426 ; Nonzero if we should toggle flag_var_tracking_assignments after
2427 ; processing options and computing its default. */
2428 fvar-tracking-assignments-toggle
2429 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2430 Toggle -fvar-tracking-assignments
2432 ; Positive if we should track uninitialized variables, negative if
2433 ; we should run the var-tracking pass only to discard debug
2434 ; annotations. When flag_var_tracking_uninit == AUTODETECT_VALUE it
2435 ; will be set according to flag_var_tracking.
2436 fvar-tracking-uninit
2437 Common Report Var(flag_var_tracking_uninit) Optimization
2438 Perform variable tracking and also tag variables that are uninitialized
2441 Common Report Var(flag_tree_vectorize) Optimization
2442 Enable vectorization on trees
2444 ftree-vectorizer-verbose=
2445 Common Joined RejectNegative Ignore
2446 Does nothing. Preserved for backward compatibility.
2448 ftree-loop-vectorize
2449 Common Report Var(flag_tree_loop_vectorize) Optimization
2450 Enable loop vectorization on trees
2453 Common Report Var(flag_tree_slp_vectorize) Optimization
2454 Enable basic block vectorization (SLP) on trees
2457 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT) Optimization
2458 Specifies the cost model for vectorization
2461 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED) Optimization
2462 Specifies the vectorization cost model for code marked with a simd directive
2465 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
2468 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
2471 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
2474 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
2477 Common RejectNegative Alias(fvect-cost-model=,dynamic)
2478 Enables the dynamic vectorizer cost model. Preserved for backward compatibility.
2481 Common RejectNegative Alias(fvect-cost-model=,unlimited)
2482 Enables the unlimited vectorizer cost model. Preserved for backward compatibility.
2484 ftree-vect-loop-version
2486 Does nothing. Preserved for backward compatibility.
2489 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2490 Enable copy propagation of scalar-evolution information.
2492 ; -fverbose-asm causes extra commentary information to be produced in
2493 ; the generated assembly code (to make it more readable). This option
2494 ; is generally only of use to those who actually need to read the
2495 ; generated assembly code (perhaps while debugging the compiler itself).
2496 ; -fno-verbose-asm, the default, causes the extra information
2497 ; to not be added and is useful when comparing two assembler files.
2499 Common Report Var(flag_verbose_asm)
2500 Add extra commentary to assembler output
2503 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2504 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2507 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2510 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2513 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2516 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2519 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2522 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
2523 Validate vtable pointers before using them.
2526 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
2529 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
2532 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
2535 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
2538 Common Var(flag_vtv_counts)
2539 Output vtable verification counters.
2542 Common Var(flag_vtv_debug)
2543 Output vtable verification pointer sets information.
2546 Common Report Var(flag_value_profile_transformations) Optimization
2547 Use expression value profiles in optimizations
2550 Common Report Var(flag_web) Init(2) Optimization
2551 Construct webs and split unrelated uses of single variable
2553 ftree-builtin-call-dce
2554 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2555 Enable conditional dead code elimination for builtin calls
2558 Common Report Var(flag_whole_program) Init(0)
2559 Perform whole program optimizations
2562 Common Report Var(flag_wrapv) Optimization
2563 Assume signed arithmetic overflow wraps around
2565 fzero-initialized-in-bss
2566 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2567 Put zero initialized data in the bss section
2570 Common JoinedOrMissing
2571 Generate debug information in default format
2574 Common JoinedOrMissing Negative(gdwarf)
2575 Generate debug information in COFF format
2578 Common JoinedOrMissing Negative(gdwarf-)
2579 Generate debug information in default version of DWARF format
2582 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2583 Generate debug information in DWARF v2 (or later) format
2586 Common JoinedOrMissing
2587 Generate debug information in default extended format
2590 Common Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
2591 Don't generate DWARF pubnames and pubtypes sections.
2594 Common Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
2595 Generate DWARF pubnames and pubtypes sections.
2598 Common Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
2599 Generate DWARF pubnames and pubtypes sections with GNU extensions.
2601 gno-record-gcc-switches
2602 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2603 Don't record gcc command line switches in DWARF DW_AT_producer.
2605 grecord-gcc-switches
2606 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2607 Record gcc command line switches in DWARF DW_AT_producer.
2610 Common Driver RejectNegative Var(dwarf_split_debug_info,0) Init(0)
2611 Don't generate debug information in separate .dwo files
2614 Common Driver RejectNegative Var(dwarf_split_debug_info,1)
2615 Generate debug information in separate .dwo files
2618 Common JoinedOrMissing Negative(gstabs+)
2619 Generate debug information in STABS format
2622 Common JoinedOrMissing Negative(gvms)
2623 Generate debug information in extended STABS format
2626 Common RejectNegative Var(dwarf_strict,0) Init(0)
2627 Emit DWARF additions beyond selected version
2630 Common Report RejectNegative Var(dwarf_strict,1)
2631 Don't emit DWARF additions beyond selected version
2634 Common Report Var(flag_gtoggle)
2635 Toggle debug information generation
2638 Common JoinedOrMissing Negative(gxcoff)
2639 Generate debug information in VMS format
2642 Common JoinedOrMissing Negative(gxcoff+)
2643 Generate debug information in XCOFF format
2646 Common JoinedOrMissing Negative(gcoff)
2647 Generate debug information in extended XCOFF format
2650 Name(compressed_debug_sections) Type(int)
2652 ; Since -gz= is completely handled in specs, the values aren't used and we
2653 ; assign arbitrary constants.
2655 Enum(compressed_debug_sections) String(none) Value(0)
2658 Enum(compressed_debug_sections) String(zlib) Value(1)
2661 Enum(compressed_debug_sections) String(zlib-gnu) Value(2)
2665 Generate compressed debug sections
2668 Common Driver Joined Enum(compressed_debug_sections)
2669 -gz=<format> Generate compressed debug sections in format <format>
2672 Driver Joined Separate
2675 Common Joined Var(plugindir_string) Init(0)
2676 -iplugindir=<dir> Set <dir> to be the default plugin directory
2679 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2680 -imultiarch <dir> Set <dir> to be the multiarch include subdirectory
2683 Driver Joined Separate
2688 no-canonical-prefixes
2701 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2702 -o <file> Place output into <file>
2705 Common Var(profile_flag)
2706 Enable function profiling
2709 Driver Var(pass_exit_codes)
2712 Common Alias(Wpedantic)
2715 Common Var(flag_pedantic_errors)
2716 Like -pedantic but issue them as errors
2722 Driver Var(use_pipes)
2725 Driver JoinedOrMissing Var(print_file_name)
2727 print-libgcc-file-name
2730 print-multi-directory
2731 Driver Var(print_multi_directory)
2734 Driver Var(print_multi_lib)
2736 print-multi-os-directory
2737 Driver Var(print_multi_os_directory)
2740 Driver Var(print_multiarch)
2743 Driver JoinedOrMissing Var(print_prog_name)
2746 Driver Var(print_search_dirs)
2749 Driver Var(print_sysroot)
2751 print-sysroot-headers-suffix
2752 Driver Var(print_sysroot_headers_suffix)
2755 Common Var(quiet_flag) RejectDriver
2756 Do not display functions compiled or elapsed time
2774 Driver Var(report_times)
2777 Driver JoinedOrMissing
2780 Driver Joined Separate
2784 ; C option, but driver must not handle as "-u ndef".
2787 Common Driver Var(verbose_flag)
2788 Enable verbose output
2791 Common Var(version_flag) RejectDriver
2792 Display the compiler's version
2795 Common Var(inhibit_warnings)
2799 Driver Separate Var(wrapper_string)
2802 Driver Joined Separate
2805 Driver RejectNegative Negative(pie)
2806 Create a shared library
2812 Driver Separate Alias(specs=)
2825 ; Documented for Fortran, but always accepted by driver.
2832 ; Documented for Go, but always accepted by driver.
2850 Driver RejectNegative Negative(shared)
2851 Create a position independent executable
2854 Driver Joined Separate
2857 Common Report Var(flag_ipa_ra) Optimization
2858 Use caller save register across calls if possible
2860 ; This comment is to ensure we retain the blank line above.