1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003-2013 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 ; True to warn about any objects definitions whose size is larger
71 ; than N bytes. Also want about function definitions whose returned
72 ; values are larger than N bytes, where N is 'larger_than_size'.
77 HOST_WIDE_INT larger_than_size
79 ; True to warn about any function whose frame size is larger
82 bool warn_frame_larger_than
85 HOST_WIDE_INT frame_larger_than_size
87 ; Nonzero means we should be saving declaration info into a .X file.
89 int flag_gen_aux_info = 0
91 ; Nonzero if we are compiling code for a shared library, zero for
96 ; These two are really VEC(char_p,heap) *.
99 void *flag_instrument_functions_exclude_functions
102 void *flag_instrument_functions_exclude_files
104 ; Generic structs (e.g. templates not explicitly specialized)
105 ; may not have a compilation unit associated with them, and so
106 ; may need to be treated differently from ordinary structs.
108 ; Structs only handled by reference (indirectly), will also usually
109 ; not need as much debugging information.
112 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
115 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
117 ; True if we should exit after parsing options.
119 bool exit_after_options
121 ; Type(s) of debugging information we are producing (if any). See
122 ; flag-types.h for the definitions of the different possible types of
123 ; debugging information.
125 enum debug_info_type write_symbols = NO_DEBUG
127 ; Level of debugging information we are producing. See flag-types.h
128 ; for the definitions of the different possible levels.
130 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
132 ; Nonzero means use GNU-only extensions in the generated symbolic
133 ; debugging information. Currently, this only has an effect when
134 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
136 bool use_gnu_debug_info_extensions
138 ; Original value of maximum field alignment in bytes, specified via
139 ; -fpack-struct=<value>.
141 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
143 ; Type of stack check.
145 enum stack_check_type flag_stack_check = NO_STACK_CHECK
147 ; True if stack usage information needs to be computed.
149 bool flag_stack_usage_info = false
151 ; -dA causes debug commentary information to be produced in
152 ; the generated assembly code (to make it more readable). This option
153 ; is generally only of use to those who actually need to read the
154 ; generated assembly code (perhaps while debugging the compiler itself).
155 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
156 ; to be a catchall for printing debug information in the assembler file.
160 ; -dP causes the rtl to be emitted as a comment in assembly.
162 int flag_dump_rtl_in_asm
164 ; Whether -da was passed (used only in handle_common_deferred_options).
166 bool flag_dump_all_passed
168 ; Other flags saying which kinds of debugging dump have been requested.
171 int rtl_dump_and_exit
174 int flag_print_asm_name
176 ; Name of top-level original source file (what was input to cpp).
177 ; This comes from the #-command at the beginning of the actual input.
178 ; If there isn't any there, then this is the cc1 input file name.
180 const char *main_input_filename
182 ; Pointer to base name in main_input_filename, with directories and a
183 ; single final extension removed, and the length of this base
187 const char *main_input_basename
190 int main_input_baselength
192 ; Which options have been printed by --help.
196 ; Which enums have been printed by --help. 0 = not printed, no
197 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
200 char *help_enum_printed
202 ; The number of columns for --help output.
204 unsigned int help_columns
206 ; Whether this options structure has been through finish_options
208 bool flag_opts_finished
210 ; What the sanitizer should instrument
212 unsigned int flag_sanitize
224 Driver Alias(coverage)
230 Common Separate Alias(d)
233 Common Joined Alias(d)
236 Common Separate Alias(dumpbase)
239 Common Separate Alias(dumpdir)
242 Driver Separate Alias(e)
245 Driver Joined Alias(e)
248 Common Warning Alias(Wextra)
251 Driver Separate Alias(Xassembler)
254 Driver JoinedOrMissing Alias(Xassembler)
257 Driver Separate Alias(Xlinker)
260 Driver JoinedOrMissing Alias(Xlinker)
263 Driver Separate Alias(u)
266 Driver Joined Alias(u)
269 Common Driver Var(help_flag)
270 Display this information
273 Common Driver Report Joined
274 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params
277 Driver Separate Alias(x)
280 Driver Joined Alias(x)
283 Driver Separate Alias(L)
286 Driver Joined Alias(L)
288 -no-canonical-prefixes
289 Driver Alias(no-canonical-prefixes)
291 -no-standard-libraries
292 Driver Alias(nostdlib)
295 Driver Var(no_sysroot_suffix)
304 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
307 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
310 Driver Alias(pass-exit-codes)
313 Common Alias(Wpedantic)
316 Common Alias(pedantic-errors)
325 Driver Separate Alias(B)
328 Driver JoinedOrMissing Alias(B)
334 Driver Separate Alias(print-file-name=)
337 Driver JoinedOrMissing Alias(print-file-name=)
339 -print-libgcc-file-name
340 Driver Alias(print-libgcc-file-name)
342 -print-multi-directory
343 Driver Alias(print-multi-directory)
346 Driver Alias(print-multi-lib)
348 -print-multi-os-directory
349 Driver Alias(print-multi-os-directory)
352 Driver Alias(print-multiarch)
355 Driver Separate Alias(print-prog-name=)
358 Driver JoinedOrMissing Alias(print-prog-name=)
361 Driver Alias(print-search-dirs)
364 Driver Alias(print-sysroot)
366 -print-sysroot-headers-suffix
367 Driver Alias(print-sysroot-headers-suffix)
373 Driver Alias(save-temps)
379 Driver Separate Alias(specs=)
382 Driver Joined Alias(specs=)
388 Driver Alias(symbolic)
392 Alias for --help=target
400 ;; The driver used to convert options such as --help into forms such
401 ;; as -fhelp; the following four entries are for compatibility with
402 ;; any direct uses of those (undocumented) -f forms
404 Common Driver Alias(-help)
407 Common Driver Joined Alias(-help=)
410 Common Driver Alias(-target-help)
413 Common Driver Alias(-version)
417 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
420 Common Joined Alias(-param)
423 Driver Separate Alias(-sysroot=)
426 Driver JoinedOrMissing
432 Driver Joined Separate
438 Driver Joined Separate
444 Common JoinedOrMissing Optimization
445 -O<number> Set optimization level to <number>
449 Optimize for space rather than speed
453 Optimize for speed disregarding exact standards compliance
457 Optimize for debugging experience rather than speed or size
469 Driver Joined Separate
475 Driver Joined Separate
496 Common RejectNegative Warning Alias(Wextra)
497 This switch is deprecated; use -Wextra instead
500 Driver JoinedOrMissing
503 Driver JoinedOrMissing
506 Driver JoinedOrMissing
509 Common Var(warn_aggregate_return) Warning
510 Warn about returning structures, unions or arrays
512 Waggressive-loop-optimizations
513 Common Var(warn_aggressive_loop_optimizations) Init(1) Warning
514 Warn if a loop with constant number of iterations triggers undefined behavior
517 Common Var(warn_array_bounds) Warning
518 Warn if an array is accessed out of bounds
521 Common Var(warn_attributes) Init(1) Warning
522 Warn about inappropriate attribute usage
525 Common Var(warn_cast_align) Warning
526 Warn about pointer casts which increase alignment
529 Common Var(warn_cpp) Init(1) Warning
530 Warn when a #warning directive is encountered
532 Wdeprecated-declarations
533 Common Var(warn_deprecated_decl) Init(1) Warning
534 Warn about uses of __attribute__((deprecated)) declarations
536 Wdisabled-optimization
537 Common Var(warn_disabled_optimization) Warning
538 Warn when an optimization pass is disabled
541 Common Var(warnings_are_errors)
542 Treat all warnings as errors
546 Treat specified warning as error
549 Common Var(extra_warnings) Warning
550 Print extra (possibly unwanted) warnings
553 Common Var(flag_fatal_errors)
554 Exit on the first error occurred
557 Common RejectNegative Joined UInteger
558 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
561 Common Var(warn_free_nonheap_object) Init(1) Warning
562 Warn when attempting to free a non-heap object
565 Common Var(warn_inline) Warning
566 Warn when an inlined function cannot be inlined
568 Winvalid-memory-model
569 Common Var(warn_invalid_memory_model) Init(1) Warning
570 Warn when an atomic memory model parameter is known to be outside the valid range.
573 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
576 Common RejectNegative Joined UInteger Warning
577 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
579 Wunsafe-loop-optimizations
580 Common Var(warn_unsafe_loop_optimizations) Warning
581 Warn if the loop cannot be optimized due to nontrivial assumptions.
584 Common Alias(Wsuggest-attribute=noreturn)
587 Common Var(warn_overflow) Init(1) Warning
588 Warn about overflow in arithmetic expressions
591 Common Var(warn_packed) Warning
592 Warn when the packed attribute has no effect on struct layout
595 Common Var(warn_padded) Warning
596 Warn when padding is required to align structure members
599 Common Var(pedantic) Warning
600 Issue warnings needed for strict compliance to the standard
603 Common Var(warn_shadow) Warning
604 Warn when one local variable shadows another
607 Common Var(warn_stack_protect) Warning
608 Warn when not issuing stack smashing protection for some reason
611 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
612 Warn if stack usage might be larger than specified amount
616 Warn about code which might break strict aliasing rules
619 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
620 Warn about code which might break strict aliasing rules
624 Warn about optimizations that assume that signed overflow is undefined
627 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
628 Warn about optimizations that assume that signed overflow is undefined
630 Wsuggest-attribute=const
631 Common Var(warn_suggest_attribute_const) Warning
632 Warn about functions which might be candidates for __attribute__((const))
634 Wsuggest-attribute=pure
635 Common Var(warn_suggest_attribute_pure) Warning
636 Warn about functions which might be candidates for __attribute__((pure))
638 Wsuggest-attribute=noreturn
639 Common Var(warn_suggest_attribute_noreturn) Warning
640 Warn about functions which might be candidates for __attribute__((noreturn))
643 Common Var(warn_system_headers) Warning
644 Do not suppress warnings from system headers
647 Common Var(warn_trampolines) Warning
648 Warn whenever a trampoline is generated
651 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
652 Warn if a comparison is always true or always false due to the limited range of the data type
655 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
656 Warn about uninitialized automatic variables
659 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
660 Warn about maybe uninitialized automatic variables
664 Does nothing. Preserved for backward compatibility.
667 Common Var(warn_unused) Init(0) Warning
668 Enable all -Wunused- warnings
670 Wunused-but-set-parameter
671 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
672 Warn when a function parameter is only set, otherwise unused
674 Wunused-but-set-variable
675 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
676 Warn when a variable is only set, otherwise unused
679 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
680 Warn when a function is unused
683 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
684 Warn when a label is unused
687 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
688 Warn when a function parameter is unused
691 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
692 Warn when an expression value is unused
695 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
696 Warn when a variable is unused
699 Common Var(warn_coverage_mismatch) Init(1) Warning
700 Warn in case profiles in -fprofile-use do not match
702 Wvector-operation-performance
703 Common Var(warn_vector_operation_performance) Warning
704 Warn when a vector operation is compiled outside the SIMD
719 Common Separate Var(aux_info_file_name)
720 -aux-info <file> Emit declaration information into <file>
723 Common Joined Alias(aux-info)
726 Common Separate RejectDriver Var(aux_base_name)
729 Common Separate RejectDriver
739 -d<letters> Enable dumps from specific passes of the compiler
742 Common Separate Var(dump_base_name)
743 -dumpbase <file> Set the file basename to be used for dumps
746 Common Separate Var(dump_dir_name)
747 -dumpdir <dir> Set the directory name to be used for dumps
759 Driver Joined Separate
761 ; This option has historically been passed down to the linker by an
762 ; accident of a %{e*} spec, so ensure it continues to be passed down
763 ; as a single option. The supported option for this purpose is
764 ; -rdynamic. See PR 47390.
768 ; The version of the C++ ABI in use. The following values are allowed:
770 ; 0: The version of the ABI believed most conformant with the C++ ABI
771 ; specification. This ABI may change as bugs are discovered and fixed.
772 ; Therefore, 0 will not necessarily indicate the same ABI in different
775 ; 1: The version of the ABI first used in G++ 3.2.
777 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
779 ; 3: The version of the ABI that fixes the missing underscore
780 ; in template non-type arguments of pointer type.
782 ; 4: The version of the ABI that introduces unambiguous mangling of
783 ; vector types. First selectable in G++ 4.5.
785 ; 5: The version of the ABI that ignores attribute const/noreturn
786 ; in function pointer mangling, and corrects mangling of decltype and
787 ; function parameters used in other parameters and the return type.
788 ; First selectable in G++ 4.6.
790 ; 6: The version of the ABI that doesn't promote scoped enums to int and
791 ; changes the mangling of template argument packs, const/static_cast,
792 ; prefix ++ and --, and a class scope function used as a template
794 ; First selectable in G++ 4.7.
796 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
797 ; corrects the mangling of lambdas in default argument scope.
798 ; First selectable in G++ 4.8.
800 ; 8: The version of the ABI that corrects the substitution behavior of
801 ; function types with function-cv-qualifiers.
802 ; First selectable in G++ 4.9.
804 ; Additional positive integers will be assigned as new versions of
805 ; the ABI become the default version of the ABI.
807 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
809 faggressive-loop-optimizations
810 Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1)
811 Aggressively optimize loops using language constraints
814 Common Report Var(align_functions,0) Optimization UInteger
815 Align the start of functions
818 Common RejectNegative Joined UInteger Var(align_functions)
821 Common Report Var(align_jumps,0) Optimization UInteger
822 Align labels which are only reached by jumping
825 Common RejectNegative Joined UInteger Var(align_jumps)
828 Common Report Var(align_labels,0) Optimization UInteger
832 Common RejectNegative Joined UInteger Var(align_labels)
835 Common Report Var(align_loops,0) Optimization UInteger
836 Align the start of loops
839 Common RejectNegative Joined UInteger Var(align_loops)
843 Does nothing. Preserved for backward compatibility.
847 Does nothing. Preserved for backward compatibility.
849 fargument-noalias-global
851 Does nothing. Preserved for backward compatibility.
853 fargument-noalias-anything
855 Does nothing. Preserved for backward compatibility.
858 Common Driver Report Joined
859 Select what to sanitize
861 fasynchronous-unwind-tables
862 Common Report Var(flag_asynchronous_unwind_tables) Optimization
863 Generate unwind tables that are exact at each instruction boundary
866 Common Report Var(flag_auto_inc_dec) Init(1)
867 Generate auto-inc/dec instructions
869 ; -fcheck-bounds causes gcc to generate array bounds checks.
870 ; For C, C++ and ObjC: defaults off.
871 ; For Java: defaults to on.
872 ; For Fortran: defaults to off.
874 Common Report Var(flag_bounds_check)
875 Generate code to check bounds before indexing arrays
877 fcheck-pointer-bounds
878 Common Report Var(flag_check_pointer_bounds)
879 Add Pointer Bounds Checker instrumentation. fchkp-* flags are used to
880 control instrumentation. Currently available for C, C++ and ObjC.
883 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
884 Replace add, compare, branch with branch on count register
886 fbranch-probabilities
887 Common Report Var(flag_branch_probabilities) Optimization
888 Use profiling information for branch probabilities
890 fbranch-target-load-optimize
891 Common Report Var(flag_branch_target_load_optimize) Optimization
892 Perform branch target load optimization before prologue / epilogue threading
894 fbranch-target-load-optimize2
895 Common Report Var(flag_branch_target_load_optimize2) Optimization
896 Perform branch target load optimization after prologue / epilogue threading
899 Common Report Var(flag_btr_bb_exclusive) Optimization
900 Restrict target load migration not to re-use registers in any basic block
903 Common Joined RejectNegative Var(common_deferred_options) Defer
904 -fcall-saved-<register> Mark <register> as being preserved across functions
907 Common Joined RejectNegative Var(common_deferred_options) Defer
908 -fcall-used-<register> Mark <register> as being corrupted by function calls
910 ; Nonzero for -fcaller-saves: allocate values in regs that need to
911 ; be saved across function calls, if that produces overall better code.
912 ; Optional now, so people can test it.
914 Common Report Var(flag_caller_saves) Optimization
915 Save registers around function calls
918 Common Report Var(flag_check_data_deps)
919 Compare the results of several data dependence analyzers.
922 Common Var(flag_check_new)
923 Check the return value of new in C++
925 fcombine-stack-adjustments
926 Common Report Var(flag_combine_stack_adjustments) Optimization
927 Looks for opportunities to reduce stack adjustments and stack references.
930 Common Report Var(flag_no_common,0) Optimization
931 Do not put uninitialized globals in the common section
935 ; Converted by the driver to -fcompare-debug= options.
938 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
939 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
941 fcompare-debug-second
942 Common Driver RejectNegative Var(flag_compare_debug)
943 Run only the second compilation of -fcompare-debug
946 Common Report Var(flag_compare_elim_after_reload) Optimization
947 Perform comparison elimination after register allocation has finished
950 Common Var(flag_conserve_stack) Optimization
951 Do not perform optimizations increasing noticeably stack usage
954 Common Report Var(flag_cprop_registers) Optimization
955 Perform a register copy-propagation optimization pass
958 Common Report Var(flag_crossjumping) Optimization
959 Perform cross-jumping optimization
962 Common Report Var(flag_cse_follow_jumps) Optimization
963 When running CSE, follow jumps to their targets
967 Does nothing. Preserved for backward compatibility.
970 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
971 Omit range reduction step when performing complex division
974 Common Report Var(flag_cx_fortran_rules) Optimization
975 Complex multiplication and division follow Fortran rules
978 Common Report Var(flag_data_sections) Optimization
979 Place data items into their own section
982 Common Report Var(common_deferred_options) Defer
983 List all available debugging counters with their limits and counts.
986 Common RejectNegative Joined Var(common_deferred_options) Defer
987 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
990 Common Joined RejectNegative Var(common_deferred_options) Defer
991 Map one directory name to another in debug information
994 Common Report Var(flag_debug_types_section) Init(0)
995 Output .debug_types section when using DWARF v4 debuginfo.
997 ; Nonzero for -fdefer-pop: don't pop args after each function call
998 ; instead save them up to pop many calls' args with one insns.
1000 Common Report Var(flag_defer_pop) Optimization
1001 Defer popping functions args from stack until later
1004 Common Report Var(flag_delayed_branch) Optimization
1005 Attempt to fill delay slots of branch instructions
1007 fdelete-dead-exceptions
1008 Common Report Var(flag_delete_dead_exceptions) Init(0)
1009 Delete dead instructions that may throw exceptions
1011 fdelete-null-pointer-checks
1012 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
1013 Delete useless null pointer checks
1015 fdevirtualize-speculatively
1016 Common Report Var(flag_devirtualize_speculatively) Optimization
1017 Perform speculative devirtualization
1020 Common Report Var(flag_devirtualize) Optimization
1021 Try to convert virtual calls to direct ones.
1023 fdiagnostics-show-location=
1024 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1025 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
1027 ; Required for these enum values.
1032 Name(diagnostic_prefixing_rule) Type(int)
1035 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1038 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1040 fdiagnostics-show-caret
1041 Common Var(flag_diagnostics_show_caret) Init(1)
1042 Show the source line with a caret indicating the column
1045 Common Alias(fdiagnostics-color=,always,never)
1049 Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1050 -fdiagnostics-color=[never|always|auto] Colorize diagnostics
1052 ; Required for these enum values.
1057 Name(diagnostic_color_rule) Type(int)
1060 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1063 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1066 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1068 fdiagnostics-show-option
1069 Common Var(flag_diagnostics_show_option) Init(1)
1070 Amend appropriate diagnostic messages with the command line option that controls them
1073 Common Joined RejectNegative Var(common_deferred_options) Defer
1074 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1077 Common Joined RejectNegative Var(common_deferred_options) Defer
1078 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1081 Common Joined RejectNegative Var(common_deferred_options) Defer
1082 -fdump-<type> Dump various compiler internals to a file
1085 Driver RejectNegative
1088 Common RejectNegative Joined Var(flag_dump_final_insns)
1089 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1092 Common RejectNegative Joined Var(flag_dump_go_spec)
1093 -fdump-go-spec=filename Write all declarations to file as Go code
1096 Common Report Var(flag_dump_noaddr)
1097 Suppress output of addresses in debugging dumps
1100 Common Var(flag_dump_passes) Init(0)
1101 Dump optimization passes
1104 Common Report Var(flag_dump_unnumbered)
1105 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1107 fdump-unnumbered-links
1108 Common Report Var(flag_dump_unnumbered_links)
1109 Suppress output of previous and next insn numbers in debugging dumps
1112 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1113 Enable CFI tables via GAS assembler directives.
1116 Common Report Var(flag_early_inlining) Init(1) Optimization
1117 Perform early inlining
1119 feliminate-dwarf2-dups
1120 Common Report Var(flag_eliminate_dwarf2_dups)
1121 Perform DWARF2 duplicate elimination
1124 Common Report Var(flag_ipa_sra) Init(0) Optimization
1125 Perform interprocedural reduction of aggregates
1127 feliminate-unused-debug-symbols
1128 Common Report Var(flag_debug_only_used_symbols)
1129 Perform unused type elimination in debug info
1131 feliminate-unused-debug-types
1132 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1133 Perform unused type elimination in debug info
1135 femit-class-debug-always
1136 Common Report Var(flag_emit_class_debug_always) Init(0)
1137 Do not suppress C++ class debug information.
1140 Common Report Var(flag_exceptions) Optimization
1141 Enable exception handling
1143 fexpensive-optimizations
1144 Common Report Var(flag_expensive_optimizations) Optimization
1145 Perform a number of minor, expensive optimizations
1148 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1149 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1152 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1155 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1158 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1164 Common Var(flag_fat_lto_objects) Init(1)
1165 Output lto objects containing both the intermediate language and binary output.
1168 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1169 Assume no NaNs or infinities are generated
1172 Common Joined RejectNegative Var(common_deferred_options) Defer
1173 -ffixed-<register> Mark <register> as being unavailable to the compiler
1176 Common Report Var(flag_float_store) Optimization
1177 Don't allocate floats and doubles in extended-precision registers
1181 Does nothing. Preserved for backward compatibility.
1184 Common Report Var(flag_forward_propagate) Optimization
1185 Perform a forward propagation pass on RTL
1188 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1189 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1192 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1195 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1197 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1199 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1202 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1204 ; Nonzero means don't put addresses of constant functions in registers.
1205 ; Used for compiling the Unix kernel, where strange substitutions are
1206 ; done on the assembly output.
1208 Common Report Var(flag_no_function_cse,0)
1209 Allow function addresses to be held in registers
1212 Common Report Var(flag_function_sections)
1213 Place each function into its own section
1216 Common Report Var(flag_gcse) Optimization
1217 Perform global common subexpression elimination
1220 Common Report Var(flag_gcse_lm) Init(1) Optimization
1221 Perform enhanced load motion during global common subexpression elimination
1224 Common Report Var(flag_gcse_sm) Init(0) Optimization
1225 Perform store motion after global common subexpression elimination
1228 Common Report Var(flag_gcse_las) Init(0) Optimization
1229 Perform redundant load after store elimination in global common subexpression
1233 Common Report Var(flag_gcse_after_reload) Optimization
1234 Perform global common subexpression elimination after register allocation
1237 ; This option is not documented yet as its semantics will change.
1239 Common Report Var(flag_graphite)
1240 Enable in and out of Graphite representation
1243 Common Report Var(flag_graphite_identity) Optimization
1244 Enable Graphite Identity transformation
1246 fhoist-adjacent-loads
1247 Common Report Var(flag_hoist_adjacent_loads) Optimization
1248 Enable hoisting adjacent loads to encourage generating conditional move
1251 floop-parallelize-all
1252 Common Report Var(flag_loop_parallelize_all) Optimization
1253 Mark all loops as parallel
1256 Common Report Var(flag_loop_strip_mine) Optimization
1257 Enable Loop Strip Mining transformation
1260 Common Report Var(flag_loop_interchange) Optimization
1261 Enable Loop Interchange transformation
1264 Common Report Var(flag_loop_block) Optimization
1265 Enable Loop Blocking transformation
1268 Common Report Var(flag_tm)
1269 Enable support for GNU transactional memory
1273 Does nothing. Preserved for backward compatibility.
1276 Common Report Var(flag_loop_optimize_isl) Optimization
1277 Enable the ISL based loop nest optimizer
1279 fstrict-volatile-bitfields
1280 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1281 Force bitfield accesses to match their type width
1283 fguess-branch-probability
1284 Common Report Var(flag_guess_branch_prob) Optimization
1285 Enable guessing of branch probabilities
1287 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1288 ; Generate position-independent code for executables if possible
1289 ; On SVR4 targets, it also controls whether or not to emit a
1290 ; string identifying the compiler.
1292 Common Report Var(flag_no_ident,0)
1293 Process #ident directives
1296 Common Report Var(flag_if_conversion) Optimization
1297 Perform conversion of conditional jumps to branchless equivalents
1300 Common Report Var(flag_if_conversion2) Optimization
1301 Perform conversion of conditional jumps to conditional execution
1304 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL)
1305 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1308 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1311 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1314 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1317 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1319 ftree-loop-if-convert
1320 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1321 Convert conditional jumps in innermost loops to branchless equivalents
1323 ftree-loop-if-convert-stores
1324 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1325 Also if-convert conditional jumps containing memory writes
1327 ; -finhibit-size-directive inhibits output of .size for ELF.
1328 ; This is used only for compiling crtstuff.c,
1329 ; and it may be extended to other effects
1330 ; needed for crtstuff.c on other systems.
1331 finhibit-size-directive
1332 Common Report Var(flag_inhibit_size_directive)
1333 Do not generate .size directives
1336 Common Report Var(flag_indirect_inlining)
1337 Perform indirect inlining
1339 ; General flag to enable inlining. Specifying -fno-inline will disable
1340 ; all inlining apart from always-inline functions.
1342 Common Report Var(flag_no_inline,0) Init(0) Optimization
1343 Enable inlining of function declared \"inline\", disabling disables all inlining
1345 finline-small-functions
1346 Common Report Var(flag_inline_small_functions) Optimization
1347 Integrate functions into their callers when code size is known not to grow
1350 Common Report Var(flag_inline_functions) Optimization
1351 Integrate functions not declared \"inline\" into their callers when profitable
1353 finline-functions-called-once
1354 Common Report Var(flag_inline_functions_called_once) Optimization
1355 Integrate functions only required by their single caller
1358 Common RejectNegative Joined Alias(finline-limit=)
1361 Common RejectNegative Joined UInteger
1362 -finline-limit=<number> Limit the size of inlined functions to <number>
1365 Common Report Var(flag_inline_atomics) Init(1) Optimization
1366 Inline __atomic operations when a lock free instruction sequence is available.
1368 finstrument-functions
1369 Common Report Var(flag_instrument_function_entry_exit)
1370 Instrument function entry and exit with profiling calls
1372 finstrument-functions-exclude-function-list=
1373 Common RejectNegative Joined
1374 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1376 finstrument-functions-exclude-file-list=
1377 Common RejectNegative Joined
1378 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1381 Common Report Var(flag_ipa_cp) Optimization
1382 Perform interprocedural constant propagation
1385 Common Report Var(flag_ipa_cp_clone) Optimization
1386 Perform cloning to make Interprocedural constant propagation stronger
1389 Common Report Var(flag_ipa_profile) Init(0) Optimization
1390 Perform interprocedural profile propagation
1393 Common Report Var(flag_ipa_pta) Init(0) Optimization
1394 Perform interprocedural points-to analysis
1397 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1398 Discover pure and const functions
1401 Common Report Var(flag_ipa_reference) Init(0) Optimization
1402 Discover readonly and non addressable static variables
1406 Does nothing. Preserved for backward compatibility.
1410 Does nothing. Preserved for backward compatibility.
1413 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1414 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1417 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1420 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1423 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1426 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT)
1427 -fira-region=[one|all|mixed] Set regions for IRA
1430 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1433 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1436 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1439 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1442 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1443 Use IRA based register pressure calculation
1444 in RTL hoist optimizations.
1447 Common Report Var(flag_ira_loop_pressure)
1448 Use IRA based register pressure calculation
1449 in RTL loop optimizations.
1451 fira-share-save-slots
1452 Common Report Var(flag_ira_share_save_slots) Init(1)
1453 Share slots for saving different hard registers.
1455 fira-share-spill-slots
1456 Common Report Var(flag_ira_share_spill_slots) Init(1)
1457 Share stack slots for spilled pseudo-registers.
1460 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1461 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1464 Common Report Var(flag_ivopts) Init(1) Optimization
1465 Optimize induction variables on trees
1468 Common Var(flag_jump_tables) Init(1) Optimization
1469 Use jump tables for sufficiently large switch statements
1471 fkeep-inline-functions
1472 Common Report Var(flag_keep_inline_functions)
1473 Generate code for functions even if they are fully inlined
1476 Common Report Var(flag_keep_static_consts) Init(1)
1477 Emit static const variables even if they are not used
1480 Common Report Var(flag_leading_underscore) Init(-1)
1481 Give external symbols a leading underscore
1485 Does nothing. Preserved for backward compatibility.
1489 Enable link-time optimization.
1492 Common RejectNegative Joined Var(flag_lto)
1493 Link-time optimization with number of parallel jobs or jobserver.
1496 Common Var(flag_lto_partition_1to1)
1497 Partition symbols and vars at linktime based on object files they originate from
1499 flto-partition=balanced
1500 Common Var(flag_lto_partition_balanced)
1501 Partition functions and vars at linktime into approximately same sized buckets
1504 Common Var(flag_lto_partition_max)
1505 Put every symbol into separate partition
1508 Common Var(flag_lto_partition_none)
1509 Disable partioning and streaming
1511 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1512 flto-compression-level=
1513 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1514 -flto-compression-level=<number> Use zlib compression level <number> for IL
1517 Common Report Var(flag_lto_report) Init(0)
1518 Report various link-time optimization statistics
1521 Common Report Var(flag_lto_report_wpa) Init(0)
1522 Report various link-time optimization statistics for WPA only
1525 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1526 Set errno after built-in math functions
1529 Common Joined RejectNegative UInteger Var(flag_max_errors)
1530 -fmax-errors=<number> Maximum number of errors to report
1533 Common Report Var(mem_report)
1534 Report on permanent memory allocation
1537 Common Report Var(mem_report_wpa)
1538 Report on permanent memory allocation in WPA only
1540 ; This will attempt to merge constant section constants, if 1 only
1541 ; string constants and constants from constant pool, if 2 also constant
1543 fmerge-all-constants
1544 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1545 Attempt to merge identical constants and constant variables
1548 Common Report Var(flag_merge_constants,1) Optimization
1549 Attempt to merge identical constants across compilation units
1551 fmerge-debug-strings
1552 Common Report Var(flag_merge_debug_strings) Init(1)
1553 Attempt to merge identical debug strings across compilation units
1556 Common RejectNegative Joined UInteger
1557 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1560 Common Report Var(flag_modulo_sched) Optimization
1561 Perform SMS based modulo scheduling before the first scheduling pass
1563 fmodulo-sched-allow-regmoves
1564 Common Report Var(flag_modulo_sched_allow_regmoves)
1565 Perform SMS based modulo scheduling with register moves allowed
1567 fmove-loop-invariants
1568 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1569 Move loop invariant computations out of loops
1572 Common Var(flag_dce) Init(1) Optimization
1573 Use the RTL dead code elimination pass
1576 Common Var(flag_dse) Init(1) Optimization
1577 Use the RTL dead store elimination pass
1579 freschedule-modulo-scheduled-loops
1580 Common Report Var(flag_resched_modulo_sched) Optimization
1581 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1583 fnon-call-exceptions
1584 Common Report Var(flag_non_call_exceptions) Optimization
1585 Support synchronous non-call exceptions
1588 Common Report Var(flag_omit_frame_pointer) Optimization
1589 When possible do not generate stack frames
1592 Common Report Var(flag_opt_info) Optimization
1593 Enable all optimization info dumps on stderr
1596 Common Joined RejectNegative Var(common_deferred_options) Defer
1597 -fopt-info[-<type>=filename] Dump compiler optimization details
1599 foptimize-register-move
1601 Does nothing. Preserved for backward compatibility.
1603 foptimize-sibling-calls
1604 Common Report Var(flag_optimize_sibling_calls) Optimization
1605 Optimize sibling and tail recursive calls
1608 Common Report Var(flag_partial_inlining)
1609 Perform partial inlining
1612 Common Report Var(pre_ipa_mem_report)
1613 Report on memory allocation before interprocedural optimization
1615 fpost-ipa-mem-report
1616 Common Report Var(post_ipa_mem_report)
1617 Report on memory allocation before interprocedural optimization
1620 Common Report Var(flag_pack_struct) Optimization
1621 Pack structure members together without holes
1624 Common RejectNegative Joined UInteger Optimization
1625 -fpack-struct=<number> Set initial maximum structure member alignment
1628 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1629 Return small aggregates in memory, not registers
1632 Common Report Var(flag_peel_loops) Optimization
1633 Perform loop peeling
1636 Common Report Var(flag_no_peephole,0) Optimization
1637 Enable machine specific peephole optimizations
1640 Common Report Var(flag_peephole2) Optimization
1641 Enable an RTL peephole pass before sched2
1644 Common Report Var(flag_pic,2) Negative(fPIE)
1645 Generate position-independent code if possible (large mode)
1648 Common Report Var(flag_pie,2) Negative(fpic)
1649 Generate position-independent code for executables if possible (large mode)
1652 Common Report Var(flag_pic,1) Negative(fpie)
1653 Generate position-independent code if possible (small mode)
1656 Common Report Var(flag_pie,1) Negative(fPIC)
1657 Generate position-independent code for executables if possible (small mode)
1660 Common Joined RejectNegative Var(common_deferred_options) Defer
1661 Specify a plugin to load
1664 Common Joined RejectNegative Var(common_deferred_options) Defer
1665 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1667 fpredictive-commoning
1668 Common Report Var(flag_predictive_commoning) Optimization
1669 Run predictive commoning optimization.
1671 fprefetch-loop-arrays
1672 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1673 Generate prefetch instructions, if available, for arrays in loops
1676 Common Report Var(profile_flag)
1677 Enable basic program profiling code
1680 Common Report Var(profile_arc_flag)
1681 Insert arc-based program profiling code
1684 Common Joined RejectNegative Var(profile_data_prefix)
1685 Set the top-level directory for storing the profile data.
1686 The default is 'pwd'.
1689 Common Report Var(flag_profile_correction)
1690 Enable correction of flow inconsistent profile data input
1694 Enable common options for generating profile info for profile feedback directed optimizations
1697 Common Joined RejectNegative
1698 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1701 Common Var(flag_profile_use)
1702 Enable common options for performing profile feedback directed optimizations
1705 Common Joined RejectNegative
1706 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1709 Common Report Var(flag_profile_values)
1710 Insert code to profile values of expressions
1713 Common Report Var(profile_report)
1714 Report on consistency of profile
1717 Common Var(common_deferred_options) Defer
1720 Common Joined RejectNegative Var(common_deferred_options) Defer
1721 -frandom-seed=<string> Make compile reproducible using <string>
1723 ; This switch causes the command line that was used to create an
1724 ; object file to be recorded into the object file. The exact format
1725 ; of this recording is target and binary file format dependent.
1726 ; It is related to the -fverbose-asm switch, but that switch only
1727 ; records information in the assembler output file as comments, so
1728 ; they never reach the object file.
1729 frecord-gcc-switches
1730 Common Report Var(flag_record_gcc_switches)
1731 Record gcc command line switches in the object file.
1734 Common Report Var(flag_pcc_struct_return,0) Optimization
1735 Return small aggregates in registers
1739 Does nothing. Preserved for backward compatibility.
1742 Common Report Var(flag_rename_registers) Init(2) Optimization
1743 Perform a register renaming optimization pass
1746 Common Report Var(flag_reorder_blocks) Optimization
1747 Reorder basic blocks to improve code placement
1749 freorder-blocks-and-partition
1750 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1751 Reorder basic blocks and partition into hot and cold sections
1754 Common Report Var(flag_reorder_functions) Optimization
1755 Reorder functions to improve code placement
1757 frerun-cse-after-loop
1758 Common Report Var(flag_rerun_cse_after_loop) Optimization
1759 Add a common subexpression elimination pass after loop optimizations
1763 Does nothing. Preserved for backward compatibility.
1766 Common Report Var(flag_rounding_math) Optimization SetByCombined
1767 Disable optimizations that assume default FP rounding behavior
1770 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1771 Enable scheduling across basic blocks
1774 Common Report Var(flag_sched_pressure) Init(0) Optimization
1775 Enable register pressure sensitive insn scheduling
1778 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1779 Allow speculative motion of non-loads
1782 Common Report Var(flag_schedule_speculative_load) Optimization
1783 Allow speculative motion of some loads
1785 fsched-spec-load-dangerous
1786 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1787 Allow speculative motion of more loads
1790 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1791 -fsched-verbose=<number> Set the verbosity level of the scheduler
1793 fsched2-use-superblocks
1794 Common Report Var(flag_sched2_use_superblocks) Optimization
1795 If scheduling post reload, do superblock scheduling
1799 Does nothing. Preserved for backward compatibility.
1802 Common Report Var(flag_schedule_insns) Optimization
1803 Reschedule instructions before register allocation
1806 Common Report Var(flag_schedule_insns_after_reload) Optimization
1807 Reschedule instructions after register allocation
1809 ; This flag should be on when a target implements non-trivial
1810 ; scheduling hooks, maybe saving some information for its own sake.
1811 ; On IA64, for example, this is used for correct bundling.
1812 fselective-scheduling
1813 Common Report Var(flag_selective_scheduling) Optimization
1814 Schedule instructions using selective scheduling algorithm
1816 fselective-scheduling2
1817 Common Report Var(flag_selective_scheduling2) Optimization
1818 Run selective scheduling after reload
1820 fsel-sched-pipelining
1821 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1822 Perform software pipelining of inner loops during selective scheduling
1824 fsel-sched-pipelining-outer-loops
1825 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1826 Perform software pipelining of outer loops during selective scheduling
1828 fsel-sched-reschedule-pipelined
1829 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1830 Reschedule pipelined regions without pipelining
1832 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1833 ; of stalled insns into the ready list.
1834 fsched-stalled-insns
1835 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1836 Allow premature scheduling of queued insns
1838 fsched-stalled-insns=
1839 Common RejectNegative Joined UInteger
1840 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1842 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1843 ; be examined for a dependency on a stalled insn that is candidate for
1844 ; premature removal from the queue of stalled insns into the ready list (has
1845 ; an effect only if the flag 'sched_stalled_insns' is set).
1846 fsched-stalled-insns-dep
1847 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1848 Set dependence distance checking in premature scheduling of queued insns
1850 fsched-stalled-insns-dep=
1851 Common RejectNegative Joined UInteger
1852 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1854 fsched-group-heuristic
1855 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1856 Enable the group heuristic in the scheduler
1858 fsched-critical-path-heuristic
1859 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1860 Enable the critical path heuristic in the scheduler
1862 fsched-spec-insn-heuristic
1863 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1864 Enable the speculative instruction heuristic in the scheduler
1866 fsched-rank-heuristic
1867 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1868 Enable the rank heuristic in the scheduler
1870 fsched-last-insn-heuristic
1871 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1872 Enable the last instruction heuristic in the scheduler
1874 fsched-dep-count-heuristic
1875 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1876 Enable the dependent count heuristic in the scheduler
1879 Common Report Var(flag_section_anchors) Optimization
1880 Access data in the same section from shared anchor points
1884 Does nothing. Preserved for backward compatibility.
1888 Does nothing. Preserved for backward compatibility.
1891 Common Report Var(flag_ree) Init(0)
1892 Turn on Redundant Extensions Elimination pass.
1895 Common Report Var(flag_show_column) Init(1)
1896 Show column numbers in diagnostics, when available. Default on
1899 Common Report Var(flag_shrink_wrap) Optimization
1900 Emit function prologues only before parts of the function that need it,
1901 rather than at the top of the function.
1904 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1905 Disable optimizations observable by IEEE signaling NaNs
1908 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1909 Disable floating point optimizations that ignore the IEEE signedness of zero
1911 fsingle-precision-constant
1912 Common Report Var(flag_single_precision_constant) Optimization
1913 Convert floating point constants to single precision constants
1915 fsplit-ivs-in-unroller
1916 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1917 Split lifetimes of induction variables when loops are unrolled
1920 Common Report Var(flag_split_stack) Init(-1)
1921 Generate discontiguous stack frames
1924 Common Report Var(flag_split_wide_types) Optimization
1925 Split wide types into independent registers
1927 fvariable-expansion-in-unroller
1928 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1929 Apply variable expansion when loops are unrolled
1932 Common Report RejectNegative Joined
1933 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1936 Common Alias(fstack-check=, specific, no)
1937 Insert stack checking code into the program. Same as -fstack-check=specific
1940 Common Var(common_deferred_options) Defer
1942 fstack-limit-register=
1943 Common RejectNegative Joined Var(common_deferred_options) Defer
1944 -fstack-limit-register=<register> Trap if the stack goes past <register>
1946 fstack-limit-symbol=
1947 Common RejectNegative Joined Var(common_deferred_options) Defer
1948 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1951 Common Report Var(flag_stack_protect, 1)
1952 Use propolice as a stack protection method
1954 fstack-protector-all
1955 Common Report RejectNegative Var(flag_stack_protect, 2)
1956 Use a stack protection method for every function
1958 fstack-protector-strong
1959 Common Report RejectNegative Var(flag_stack_protect, 3)
1960 Use a smart stack protection method for certain functions
1963 Common RejectNegative Var(flag_stack_usage)
1964 Output stack usage information on a per-function basis
1968 Does nothing. Preserved for backward compatibility.
1970 ; Nonzero if we should do (language-dependent) alias analysis.
1971 ; Typically, this analysis will assume that expressions of certain
1972 ; types do not alias expressions of certain other types. Only used
1973 ; if alias analysis (in general) is enabled.
1975 Common Report Var(flag_strict_aliasing) Optimization
1976 Assume strict aliasing rules apply
1979 Common Report Var(flag_strict_overflow)
1980 Treat signed overflow as undefined
1983 Common Report Var(flag_sync_libcalls) Init(1)
1984 Implement __atomic operations via libcalls to legacy __sync functions
1987 Common Report Var(flag_syntax_only)
1988 Check for syntax errors, then stop
1991 Common Report Var(flag_test_coverage)
1992 Create data files needed by \"gcov\"
1995 Common Report Var(flag_thread_jumps) Optimization
1996 Perform jump threading optimizations
1999 Common Report Var(time_report)
2000 Report the time taken by each compiler pass
2003 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2004 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
2007 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2010 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2013 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2016 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2019 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2022 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
2023 Reorder top level functions, variables, and asms
2026 Common Report Var(flag_tracer)
2027 Perform superblock formation via tail duplication
2029 ; Zero means that floating-point math operations cannot generate a
2030 ; (user-visible) trap. This is the case, for example, in nonstop
2031 ; IEEE 754 arithmetic.
2033 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
2034 Assume floating-point operations can trap
2037 Common Report Var(flag_trapv) Optimization
2038 Trap for signed overflow in addition, subtraction and multiplication
2041 Common Report Var(flag_tree_ccp) Optimization
2042 Enable SSA-CCP optimization on trees
2045 Common Report Var(flag_tree_bit_ccp) Optimization
2046 Enable SSA-BIT-CCP optimization on trees
2050 Does nothing. Preserved for backward compatibility.
2053 Common Report Var(flag_tree_ch) Optimization
2054 Enable loop header copying on trees
2056 ftree-coalesce-inlined-vars
2057 Common Report Var(flag_ssa_coalesce_vars,1) Init(2) RejectNegative Optimization
2058 Enable coalescing of copy-related user variables that are inlined
2061 Common Report Var(flag_ssa_coalesce_vars,2) Optimization
2062 Enable coalescing of all copy-related user variables
2065 Common Report Var(flag_tree_copyrename) Optimization
2066 Replace SSA temporaries with better names in copies
2069 Common Report Var(flag_tree_copy_prop) Optimization
2070 Enable copy propagation on trees
2072 ftree-store-copy-prop
2074 Does nothing. Preserved for backward compatibility.
2077 Common Report Var(flag_tree_cselim) Init(2) Optimization
2078 Transform condition stores into unconditional ones
2080 ftree-switch-conversion
2081 Common Report Var(flag_tree_switch_conversion) Optimization
2082 Perform conversions of switch initializations.
2085 Common Report Var(flag_tree_dce) Optimization
2086 Enable SSA dead code elimination optimization on trees
2088 ftree-dominator-opts
2089 Common Report Var(flag_tree_dom) Optimization
2090 Enable dominator optimizations
2093 Common Report Var(flag_tree_tail_merge) Optimization
2094 Enable tail merging on trees
2097 Common Report Var(flag_tree_dse) Optimization
2098 Enable dead store elimination
2101 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2102 Enable forward propagation on trees
2105 Common Report Var(flag_tree_fre) Optimization
2106 Enable Full Redundancy Elimination (FRE) on trees
2109 Common Report Var(flag_optimize_strlen) Optimization
2110 Enable string length optimizations on trees
2112 ftree-loop-distribution
2113 Common Report Var(flag_tree_loop_distribution) Optimization
2114 Enable loop distribution on trees
2116 ftree-loop-distribute-patterns
2117 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2118 Enable loop distribution for patterns transformed into a library call
2121 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2122 Enable loop invariant motion on trees
2125 Common Alias(floop-interchange)
2126 Enable loop interchange transforms. Same as -floop-interchange
2129 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2130 Create canonical induction variables in loops
2133 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2134 Enable loop optimizations on tree level
2136 ftree-parallelize-loops=
2137 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2138 Enable automatic parallelization of loops
2141 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2142 Enable hoisting loads from conditional pointers.
2145 Common Report Var(flag_tree_pre) Optimization
2146 Enable SSA-PRE optimization on trees
2149 Common Report Var(flag_tree_partial_pre) Optimization
2150 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination
2153 Common Report Var(flag_tree_pta) Init(1) Optimization
2154 Perform function-local points-to analysis on trees.
2157 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2158 Enable reassociation on tree level
2162 Does nothing. Preserved for backward compatibility.
2165 Common Report Var(flag_tree_sink) Optimization
2166 Enable SSA code sinking on trees
2169 Common Report Var(flag_tree_slsr) Optimization
2170 Perform straight-line strength reduction
2173 Common Report Var(flag_tree_sra) Optimization
2174 Perform scalar replacement of aggregates
2177 Common Report Var(flag_tree_ter) Optimization
2178 Replace temporary expressions in the SSA->normal pass
2181 Common Report Var(flag_tree_live_range_split) Optimization
2182 Perform live range splitting during the SSA->normal pass
2185 Common Report Var(flag_tree_vrp) Init(0) Optimization
2186 Perform Value Range Propagation on trees
2189 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2190 Compile whole compilation unit at a time
2193 Common Report Var(flag_unroll_loops) Optimization
2194 Perform loop unrolling when iteration count is known
2197 Common Report Var(flag_unroll_all_loops) Optimization
2198 Perform loop unrolling for all loops
2200 ; Nonzero means that loop optimizer may assume that the induction variables
2201 ; that control loops do not overflow and that the loops with nontrivial
2202 ; exit condition are not infinite
2203 funsafe-loop-optimizations
2204 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2205 Allow loop optimizations to assume that the loops behave in normal way
2208 Common Report Var(flag_associative_math) SetByCombined
2209 Allow optimization for floating-point arithmetic which may change the
2210 result of the operation due to rounding.
2213 Common Report Var(flag_reciprocal_math) SetByCombined
2214 Same as -fassociative-math for expressions which include division.
2216 ; Nonzero means that unsafe floating-point math optimizations are allowed
2217 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2218 ; are allowed to assume that their arguments and results are "normal"
2219 ; (e.g., nonnegative for SQRT).
2220 funsafe-math-optimizations
2221 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2222 Allow math optimizations that may violate IEEE or ISO standards
2225 Common Report Var(flag_unswitch_loops) Optimization
2226 Perform loop unswitching
2229 Common Report Var(flag_unwind_tables) Optimization
2230 Just generate unwind tables for exception handling
2233 Common Negative(fuse-ld=gold)
2234 Use the bfd linker instead of the default linker
2237 Common Negative(fuse-ld=bfd)
2238 Use the gold linker instead of the default linker
2243 ; Positive if we should track variables, negative if we should run
2244 ; the var-tracking pass only to discard debug annotations, zero if
2245 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2246 ; will be set according to optimize, debug_info_level and debug_hooks
2247 ; in process_options ().
2249 Common Report Var(flag_var_tracking) Init(2) Optimization
2250 Perform variable tracking
2252 ; Positive if we should track variables at assignments, negative if
2253 ; we should run the var-tracking pass only to discard debug
2254 ; annotations. When flag_var_tracking_assignments ==
2255 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2256 fvar-tracking-assignments
2257 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2258 Perform variable tracking by annotating assignments
2260 ; Nonzero if we should toggle flag_var_tracking_assignments after
2261 ; processing options and computing its default. */
2262 fvar-tracking-assignments-toggle
2263 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2264 Toggle -fvar-tracking-assignments
2266 ; Positive if we should track uninitialized variables, negative if
2267 ; we should run the var-tracking pass only to discard debug
2268 ; annotations. When flag_var_tracking_uninit == AUTODETECT_VALUE it
2269 ; will be set according to flag_var_tracking.
2270 fvar-tracking-uninit
2271 Common Report Var(flag_var_tracking_uninit) Optimization
2272 Perform variable tracking and also tag variables that are uninitialized
2275 Common Report Var(flag_tree_vectorize) Optimization
2276 Enable vectorization on trees
2278 ftree-vectorizer-verbose=
2279 Common RejectNegative Joined UInteger Var(common_deferred_options) Defer
2280 -ftree-vectorizer-verbose=<number> This switch is deprecated. Use -fopt-info instead.
2282 ftree-loop-vectorize
2283 Common Report Var(flag_tree_loop_vectorize) Optimization
2284 Enable loop vectorization on trees
2287 Common Report Var(flag_tree_slp_vectorize) Optimization
2288 Enable basic block vectorization (SLP) on trees
2291 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT)
2292 Specifies the cost model for vectorization
2295 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
2298 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
2301 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
2304 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
2307 Common RejectNegative Alias(fvect-cost-model=,dynamic)
2308 Enables the dynamic vectorizer cost model. Preserved for backward compatibility.
2311 Common RejectNegative Alias(fvect-cost-model=,unlimited)
2312 Enables the unlimited vectorizer cost model. Preserved for backward compatibility.
2314 ftree-vect-loop-version
2316 Does nothing. Preserved for backward compatibility.
2319 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2320 Enable copy propagation of scalar-evolution information.
2322 ; -fverbose-asm causes extra commentary information to be produced in
2323 ; the generated assembly code (to make it more readable). This option
2324 ; is generally only of use to those who actually need to read the
2325 ; generated assembly code (perhaps while debugging the compiler itself).
2326 ; -fno-verbose-asm, the default, causes the extra information
2327 ; to not be added and is useful when comparing two assembler files.
2329 Common Report Var(flag_verbose_asm)
2330 Add extra commentary to assembler output
2333 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2334 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2337 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2340 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2343 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2346 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2349 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2352 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
2353 Validate vtable pointers before using them.
2356 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
2359 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
2362 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
2365 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
2368 Common Var(flag_vtv_counts)
2369 Output vtable verification counters.
2372 Common Var(flag_vtv_debug)
2373 Output vtable verification pointer sets information.
2376 Common Report Var(flag_value_profile_transformations) Optimization
2377 Use expression value profiles in optimizations
2380 Common Report Var(flag_web) Init(2) Optimization
2381 Construct webs and split unrelated uses of single variable
2383 ftree-builtin-call-dce
2384 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2385 Enable conditional dead code elimination for builtin calls
2388 Common Report Var(flag_whole_program) Init(0) Optimization
2389 Perform whole program optimizations
2392 Common Report Var(flag_wrapv) Optimization
2393 Assume signed arithmetic overflow wraps around
2395 fzero-initialized-in-bss
2396 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2397 Put zero initialized data in the bss section
2400 Common JoinedOrMissing
2401 Generate debug information in default format
2404 Common JoinedOrMissing Negative(gdwarf)
2405 Generate debug information in COFF format
2408 Common JoinedOrMissing Negative(gdwarf-)
2409 Generate debug information in default version of DWARF format
2412 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2413 Generate debug information in DWARF v2 (or later) format
2416 Common JoinedOrMissing
2417 Generate debug information in default extended format
2420 Common Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
2421 Don't generate DWARF pubnames and pubtypes sections.
2424 Common Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
2425 Generate DWARF pubnames and pubtypes sections.
2428 Common Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
2429 Generate DWARF pubnames and pubtypes sections with GNU extensions.
2431 gno-record-gcc-switches
2432 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2433 Don't record gcc command line switches in DWARF DW_AT_producer.
2435 grecord-gcc-switches
2436 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2437 Record gcc command line switches in DWARF DW_AT_producer.
2440 Common Driver RejectNegative Var(dwarf_split_debug_info,0) Init(0)
2441 Don't generate debug information in separate .dwo files
2444 Common Driver RejectNegative Var(dwarf_split_debug_info,1)
2445 Generate debug information in separate .dwo files
2448 Common JoinedOrMissing Negative(gstabs+)
2449 Generate debug information in STABS format
2452 Common JoinedOrMissing Negative(gvms)
2453 Generate debug information in extended STABS format
2456 Common RejectNegative Var(dwarf_strict,0) Init(0)
2457 Emit DWARF additions beyond selected version
2460 Common Report RejectNegative Var(dwarf_strict,1)
2461 Don't emit DWARF additions beyond selected version
2464 Common Report Var(flag_gtoggle)
2465 Toggle debug information generation
2468 Common JoinedOrMissing Negative(gxcoff)
2469 Generate debug information in VMS format
2472 Common JoinedOrMissing Negative(gxcoff+)
2473 Generate debug information in XCOFF format
2476 Common JoinedOrMissing Negative(gcoff)
2477 Generate debug information in extended XCOFF format
2480 Driver Joined Separate
2483 Common Joined Var(plugindir_string) Init(0)
2484 -iplugindir=<dir> Set <dir> to be the default plugin directory
2487 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2488 -imultiarch <dir> Set <dir> to be the multiarch include subdirectory
2491 Driver Joined Separate
2496 no-canonical-prefixes
2509 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2510 -o <file> Place output into <file>
2513 Common Var(profile_flag)
2514 Enable function profiling
2517 Driver Var(pass_exit_codes)
2520 Common Alias(Wpedantic)
2523 Common Var(flag_pedantic_errors)
2524 Like -pedantic but issue them as errors
2530 Driver Var(use_pipes)
2533 Driver JoinedOrMissing Var(print_file_name)
2535 print-libgcc-file-name
2538 print-multi-directory
2539 Driver Var(print_multi_directory)
2542 Driver Var(print_multi_lib)
2544 print-multi-os-directory
2545 Driver Var(print_multi_os_directory)
2548 Driver Var(print_multiarch)
2551 Driver JoinedOrMissing Var(print_prog_name)
2554 Driver Var(print_search_dirs)
2557 Driver Var(print_sysroot)
2559 print-sysroot-headers-suffix
2560 Driver Var(print_sysroot_headers_suffix)
2563 Common Var(quiet_flag) RejectDriver
2564 Do not display functions compiled or elapsed time
2582 Driver Var(report_times)
2585 Driver JoinedOrMissing
2588 Driver Joined Separate
2592 ; C option, but driver must not handle as "-u ndef".
2595 Common Driver Var(verbose_flag)
2596 Enable verbose output
2599 Common Var(version_flag) RejectDriver
2600 Display the compiler's version
2603 Common Var(inhibit_warnings)
2607 Driver Separate Var(wrapper_string)
2610 Driver Joined Separate
2613 Driver RejectNegative Negative(pie)
2614 Create a shared library
2620 Driver Separate Alias(specs=)
2633 ; Documented for Fortran, but always accepted by driver.
2640 ; Documented for Go, but always accepted by driver.
2655 Driver RejectNegative Negative(shared)
2656 Create a position independent executable
2659 Driver Joined Separate
2661 ; This comment is to ensure we retain the blank line above.