1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
4 ; Free Software Foundation, Inc.
6 ; This file is part of GCC.
8 ; GCC is free software; you can redistribute it and/or modify it under
9 ; the terms of the GNU General Public License as published by the Free
10 ; Software Foundation; either version 3, or (at your option) any later
13 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 ; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 ; You should have received a copy of the GNU General Public License
19 ; along with GCC; see the file COPYING3. If not see
20 ; <http://www.gnu.org/licenses/>.
22 ; See the GCC internals manual (options.texi) for a description of this file's format.
24 ; Please try to keep this file in ASCII collating order.
35 ; Not used directly to control optimizations, only to save -Ofast
36 ; setting for "optimize" attributes.
40 ; True if this is the lto front end. This is used to disable gimple
41 ; generation and lowering passes that are normally run on the output
42 ; of a front end. These passes must be bypassed for lto since they
43 ; have already been done before the gimple was written.
47 ; 0 means straightforward implementation of complex divide acceptable.
48 ; 1 means wide ranges of inputs must work for complex divide.
49 ; 2 means C99-like requirements for complex multiply and divide.
51 int flag_complex_method = 1
53 ; Nonzero if subexpressions must be evaluated from left-to-right.
55 int flag_evaluation_order = 0
57 ; Language specific warning pass for unused results.
59 bool flag_warn_unused_result = false
64 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
68 ; True to warn about any objects definitions whose size is larger
69 ; than N bytes. Also want about function definitions whose returned
70 ; values are larger than N bytes, where N is 'larger_than_size'.
75 HOST_WIDE_INT larger_than_size
77 ; True to warn about any function whose frame size is larger
80 bool warn_frame_larger_than
83 HOST_WIDE_INT frame_larger_than_size
85 ; Nonzero means we should be saving declaration info into a .X file.
87 int flag_gen_aux_info = 0
89 ; Nonzero if we are compiling code for a shared library, zero for
94 ; These two are really VEC(char_p,heap) *.
97 void *flag_instrument_functions_exclude_functions
100 void *flag_instrument_functions_exclude_files
102 ; Generic structs (e.g. templates not explicitly specialized)
103 ; may not have a compilation unit associated with them, and so
104 ; may need to be treated differently from ordinary structs.
106 ; Structs only handled by reference (indirectly), will also usually
107 ; not need as much debugging information.
110 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
113 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
115 ; True if we should exit after parsing options.
117 bool exit_after_options
119 ; Type(s) of debugging information we are producing (if any). See
120 ; flag-types.h for the definitions of the different possible types of
121 ; debugging information.
123 enum debug_info_type write_symbols = NO_DEBUG
125 ; Level of debugging information we are producing. See flag-types.h
126 ; for the definitions of the different possible levels.
128 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
130 ; Nonzero means use GNU-only extensions in the generated symbolic
131 ; debugging information. Currently, this only has an effect when
132 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
134 bool use_gnu_debug_info_extensions
136 ; Original value of maximum field alignment in bytes, specified via
137 ; -fpack-struct=<value>.
139 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
142 enum vect_verbosity_levels user_vect_verbosity_level = MAX_VERBOSITY_LEVEL
144 ; Type of stack check.
146 enum stack_check_type flag_stack_check = NO_STACK_CHECK
148 ; True if stack usage information needs to be computed.
150 bool flag_stack_usage_info = false
152 ; -dA causes debug commentary information to be produced in
153 ; the generated assembly code (to make it more readable). This option
154 ; is generally only of use to those who actually need to read the
155 ; generated assembly code (perhaps while debugging the compiler itself).
156 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
157 ; to be a catchall for printing debug information in the assembler file.
161 ; -dP causes the rtl to be emitted as a comment in assembly.
163 int flag_dump_rtl_in_asm
165 ; Whether -da was passed (used only in handle_common_deferred_options).
167 bool flag_dump_all_passed
169 ; Other flags saying which kinds of debugging dump have been requested.
172 int rtl_dump_and_exit
175 int flag_print_asm_name
178 enum graph_dump_types graph_dump_format = no_graph
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
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)
301 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
304 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
307 Driver Alias(pass-exit-codes)
310 Common Alias(pedantic)
313 Common Alias(pedantic-errors)
322 Driver Separate Alias(B)
325 Driver JoinedOrMissing Alias(B)
331 Driver Separate Alias(print-file-name=)
334 Driver JoinedOrMissing Alias(print-file-name=)
336 -print-libgcc-file-name
337 Driver Alias(print-libgcc-file-name)
339 -print-multi-directory
340 Driver Alias(print-multi-directory)
343 Driver Alias(print-multi-lib)
345 -print-multi-os-directory
346 Driver Alias(print-multi-os-directory)
349 Driver Alias(print-multiarch)
352 Driver Separate Alias(print-prog-name=)
355 Driver JoinedOrMissing Alias(print-prog-name=)
358 Driver Alias(print-search-dirs)
361 Driver Alias(print-sysroot)
363 -print-sysroot-headers-suffix
364 Driver Alias(print-sysroot-headers-suffix)
370 Driver Alias(save-temps)
376 Driver Separate Alias(specs=)
379 Driver Joined Alias(specs=)
385 Driver Alias(symbolic)
389 Alias for --help=target
397 ;; The driver used to convert options such as --help into forms such
398 ;; as -fhelp; the following four entries are for compatibility with
399 ;; any direct uses of those (undocumented) -f forms
401 Common Driver Alias(-help)
404 Common Driver Joined Alias(-help=)
407 Common Driver Alias(-target-help)
410 Common Driver Alias(-version)
414 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
417 Common Joined Alias(-param)
420 Driver Separate Alias(-sysroot=)
423 Driver JoinedOrMissing
429 Driver Joined Separate
435 Driver Joined Separate
441 Common JoinedOrMissing Optimization
442 -O<number> Set optimization level to <number>
446 Optimize for space rather than speed
450 Optimize for speed disregarding exact standards compliance
462 Driver Joined Separate
468 Driver Joined Separate
489 Common RejectNegative Warning Alias(Wextra)
490 This switch is deprecated; use -Wextra instead
493 Driver JoinedOrMissing
496 Driver JoinedOrMissing
499 Driver JoinedOrMissing
502 Common Var(warn_aggregate_return) Warning
503 Warn about returning structures, unions or arrays
506 Common Var(warn_array_bounds) Warning
507 Warn if an array is accessed out of bounds
510 Common Var(warn_attributes) Init(1) Warning
511 Warn about inappropriate attribute usage
514 Common Var(warn_cast_align) Warning
515 Warn about pointer casts which increase alignment
518 Common Var(warn_cpp) Init(1) Warning
519 Warn when a #warning directive is encountered
521 Wdeprecated-declarations
522 Common Var(warn_deprecated_decl) Init(1) Warning
523 Warn about uses of __attribute__((deprecated)) declarations
525 Wdisabled-optimization
526 Common Var(warn_disabled_optimization) Warning
527 Warn when an optimization pass is disabled
530 Common Var(warnings_are_errors)
531 Treat all warnings as errors
535 Treat specified warning as error
538 Common Var(extra_warnings) Warning
539 Print extra (possibly unwanted) warnings
542 Common Var(flag_fatal_errors)
543 Exit on the first error occurred
546 Common RejectNegative Joined UInteger
547 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
550 Common Var(warn_free_nonheap_object) Init(1) Warning
551 Warn when attempting to free a non-heap object
554 Common Var(warn_inline) Warning
555 Warn when an inlined function cannot be inlined
557 Winvalid-memory-model
558 Common Var(warn_invalid_memory_model) Init(1) Warning
559 Warn when an atomic memory model parameter is known to be outside the valid range.
562 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
565 Common RejectNegative Joined UInteger Warning
566 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
568 Wunsafe-loop-optimizations
569 Common Var(warn_unsafe_loop_optimizations) Warning
570 Warn if the loop cannot be optimized due to nontrivial assumptions.
573 Common Var(warn_missing_noreturn) Warning
574 Warn about functions which might be candidates for __attribute__((noreturn))
577 Common Var(warn_overflow) Init(1) Warning
578 Warn about overflow in arithmetic expressions
581 Common Var(warn_packed) Warning
582 Warn when the packed attribute has no effect on struct layout
585 Common Var(warn_padded) Warning
586 Warn when padding is required to align structure members
589 Common Var(warn_shadow) Warning
590 Warn when one local variable shadows another
593 Common Var(warn_stack_protect) Warning
594 Warn when not issuing stack smashing protection for some reason
597 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
598 Warn if stack usage might be larger than specified amount
602 Warn about code which might break strict aliasing rules
605 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Init(-1) Warning
606 Warn about code which might break strict aliasing rules
610 Warn about optimizations that assume that signed overflow is undefined
613 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Init(-1) Warning
614 Warn about optimizations that assume that signed overflow is undefined
616 Wsuggest-attribute=const
617 Common Var(warn_suggest_attribute_const) Warning
618 Warn about functions which might be candidates for __attribute__((const))
620 Wsuggest-attribute=pure
621 Common Var(warn_suggest_attribute_pure) Warning
622 Warn about functions which might be candidates for __attribute__((pure))
624 Wsuggest-attribute=noreturn
625 Common Var(warn_suggest_attribute_noreturn) Warning
626 Warn about functions which might be candidates for __attribute__((noreturn))
629 Common Var(warn_switch) Warning
630 Warn about enumerated switches, with no default, missing a case
633 Common Var(warn_switch_default) Warning
634 Warn about enumerated switches missing a \"default:\" statement
637 Common Var(warn_switch_enum) Warning
638 Warn about all enumerated switches missing a specific case
641 Common Var(warn_system_headers) Warning
642 Do not suppress warnings from system headers
645 Common Var(warn_trampolines) Warning
646 Warn whenever a trampoline is generated
649 Common Var(warn_type_limits) Init(-1) Warning
650 Warn if a comparison is always true or always false due to the limited range of the data type
653 Common Var(warn_uninitialized) Init(-1) Warning
654 Warn about uninitialized automatic variables
657 Common Var(warn_maybe_uninitialized) Warning
658 Warn about maybe uninitialized automatic variables
662 Does nothing. Preserved for backward compatibility.
665 Common Var(warn_unused) Init(0) Warning
666 Enable all -Wunused- warnings
668 Wunused-but-set-parameter
669 Common Var(warn_unused_but_set_parameter) Init(-1) Warning
670 Warn when a function parameter is only set, otherwise unused
672 Wunused-but-set-variable
673 Common Var(warn_unused_but_set_variable) Init(-1) Warning
674 Warn when a variable is only set, otherwise unused
677 Common Var(warn_unused_function) Init(-1) Warning
678 Warn when a function is unused
681 Common Var(warn_unused_label) Init(-1) Warning
682 Warn when a label is unused
685 Common Var(warn_unused_parameter) Init(-1) Warning
686 Warn when a function parameter is unused
689 Common Var(warn_unused_value) Init(-1) Warning
690 Warn when an expression value is unused
693 Common Var(warn_unused_variable) Init(-1) Warning
694 Warn when a variable is unused
697 Common Var(warn_coverage_mismatch) Init(1) Warning
698 Warn in case profiles in -fprofile-use do not match
700 Wvector-operation-performance
701 Common Var(warn_vector_operation_performance) Warning
702 Warn when a vector operation is compiled outside the SIMD
717 Common Separate Var(aux_info_file_name)
718 -aux-info <file> Emit declaration information into <file>
721 Common Joined Alias(aux-info)
724 Common Separate RejectDriver Var(aux_base_name)
727 Common Separate RejectDriver
737 -d<letters> Enable dumps from specific passes of the compiler
740 Common Separate Var(dump_base_name)
741 -dumpbase <file> Set the file basename to be used for dumps
744 Common Separate Var(dump_dir_name)
745 -dumpdir <dir> Set the directory name to be used for dumps
757 Driver Joined Separate
759 ; This option has historically been passed down to the linker by an
760 ; accident of a %{e*} spec, so ensure it continues to be passed down
761 ; as a single option. The supported option for this purpose is
762 ; -rdynamic. See PR 47390.
766 ; The version of the C++ ABI in use. The following values are allowed:
768 ; 0: The version of the ABI believed most conformant with the C++ ABI
769 ; specification. This ABI may change as bugs are discovered and fixed.
770 ; Therefore, 0 will not necessarily indicate the same ABI in different
773 ; 1: The version of the ABI first used in G++ 3.2.
775 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
777 ; 3: The version of the ABI that fixes the missing underscore
778 ; in template non-type arguments of pointer type.
780 ; 4: The version of the ABI that introduces unambiguous mangling of
781 ; vector types. First selectable in G++ 4.5.
783 ; 5: The version of the ABI that ignores attribute const/noreturn
784 ; in function pointer mangling, and corrects mangling of decltype and
785 ; function parameters used in other parameters and the return type.
786 ; First selectable in G++ 4.6.
788 ; 6: The version of the ABI that doesn't promote scoped enums to int and
789 ; changes the mangling of template argument packs, const/static_cast,
790 ; prefix ++ and --, and a class scope function used as a template
792 ; First selectable in G++ 4.7.
794 ; Additional positive integers will be assigned as new versions of
795 ; the ABI become the default version of the ABI.
797 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
800 Common Report Var(align_functions,0) Optimization UInteger
801 Align the start of functions
804 Common RejectNegative Joined UInteger Var(align_functions)
807 Common Report Var(align_jumps,0) Optimization UInteger
808 Align labels which are only reached by jumping
811 Common RejectNegative Joined UInteger Var(align_jumps)
814 Common Report Var(align_labels,0) Optimization UInteger
818 Common RejectNegative Joined UInteger Var(align_labels)
821 Common Report Var(align_loops,0) Optimization UInteger
822 Align the start of loops
825 Common RejectNegative Joined UInteger Var(align_loops)
829 Does nothing. Preserved for backward compatibility.
833 Does nothing. Preserved for backward compatibility.
835 fargument-noalias-global
837 Does nothing. Preserved for backward compatibility.
839 fargument-noalias-anything
841 Does nothing. Preserved for backward compatibility.
843 fasynchronous-unwind-tables
844 Common Report Var(flag_asynchronous_unwind_tables) Optimization
845 Generate unwind tables that are exact at each instruction boundary
848 Common Report Var(flag_auto_inc_dec) Init(1)
849 Generate auto-inc/dec instructions
851 ; -fcheck-bounds causes gcc to generate array bounds checks.
852 ; For C, C++ and ObjC: defaults off.
853 ; For Java: defaults to on.
854 ; For Fortran: defaults to off.
856 Common Report Var(flag_bounds_check)
857 Generate code to check bounds before indexing arrays
860 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
861 Replace add, compare, branch with branch on count register
863 fbranch-probabilities
864 Common Report Var(flag_branch_probabilities) Optimization
865 Use profiling information for branch probabilities
867 fbranch-target-load-optimize
868 Common Report Var(flag_branch_target_load_optimize) Optimization
869 Perform branch target load optimization before prologue / epilogue threading
871 fbranch-target-load-optimize2
872 Common Report Var(flag_branch_target_load_optimize2) Optimization
873 Perform branch target load optimization after prologue / epilogue threading
876 Common Report Var(flag_btr_bb_exclusive) Optimization
877 Restrict target load migration not to re-use registers in any basic block
880 Common Joined RejectNegative Var(common_deferred_options) Defer
881 -fcall-saved-<register> Mark <register> as being preserved across functions
884 Common Joined RejectNegative Var(common_deferred_options) Defer
885 -fcall-used-<register> Mark <register> as being corrupted by function calls
887 ; Nonzero for -fcaller-saves: allocate values in regs that need to
888 ; be saved across function calls, if that produces overall better code.
889 ; Optional now, so people can test it.
891 Common Report Var(flag_caller_saves) Optimization
892 Save registers around function calls
895 Common Report Var(flag_check_data_deps)
896 Compare the results of several data dependence analyzers.
898 fcombine-stack-adjustments
899 Common Report Var(flag_combine_stack_adjustments) Optimization
900 Looks for opportunities to reduce stack adjustments and stack references.
903 Common Report Var(flag_no_common,0) Optimization
904 Do not put uninitialized globals in the common section
908 ; Converted by the driver to -fcompare-debug= options.
911 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
912 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
914 fcompare-debug-second
915 Common Driver RejectNegative Var(flag_compare_debug)
916 Run only the second compilation of -fcompare-debug
919 Common Report Var(flag_compare_elim_after_reload) Optimization
920 Perform comparison elimination after register allocation has finished
923 Common Var(flag_conserve_stack) Optimization
924 Do not perform optimizations increasing noticeably stack usage
927 Common Report Var(flag_cprop_registers) Optimization
928 Perform a register copy-propagation optimization pass
931 Common Report Var(flag_crossjumping) Optimization
932 Perform cross-jumping optimization
935 Common Report Var(flag_cse_follow_jumps) Optimization
936 When running CSE, follow jumps to their targets
940 Does nothing. Preserved for backward compatibility.
943 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
944 Omit range reduction step when performing complex division
947 Common Report Var(flag_cx_fortran_rules) Optimization
948 Complex multiplication and division follow Fortran rules
951 Common Report Var(flag_data_sections) Optimization
952 Place data items into their own section
955 Common Report Var(common_deferred_options) Defer
956 List all available debugging counters with their limits and counts.
959 Common RejectNegative Joined Var(common_deferred_options) Defer
960 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
963 Common Joined RejectNegative Var(common_deferred_options) Defer
964 Map one directory name to another in debug information
967 Common Report Var(flag_debug_types_section) Init(1)
968 Output .debug_types section when using DWARF v4 debuginfo.
970 ; Nonzero for -fdefer-pop: don't pop args after each function call
971 ; instead save them up to pop many calls' args with one insns.
973 Common Report Var(flag_defer_pop) Optimization
974 Defer popping functions args from stack until later
977 Common Report Var(flag_delayed_branch) Optimization
978 Attempt to fill delay slots of branch instructions
980 fdelete-null-pointer-checks
981 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
982 Delete useless null pointer checks
985 Common Report Var(flag_devirtualize) Optimization
986 Try to convert virtual calls to direct ones.
988 fdiagnostics-show-location=
989 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
990 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
992 ; Required for these enum values.
997 Name(diagnostic_prefixing_rule) Type(int)
1000 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1003 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1005 fdiagnostics-show-option
1006 Common Var(flag_diagnostics_show_option) Init(1)
1007 Amend appropriate diagnostic messages with the command line option that controls them
1010 Common Joined RejectNegative Var(common_deferred_options) Defer
1011 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1014 Common Joined RejectNegative Var(common_deferred_options) Defer
1015 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1018 Common Joined RejectNegative Var(common_deferred_options) Defer
1019 -fdump-<type> Dump various compiler internals to a file
1022 Driver RejectNegative
1025 Common RejectNegative Joined Var(flag_dump_final_insns)
1026 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1029 Common RejectNegative Joined Var(flag_dump_go_spec)
1030 -fdump-go-spec=filename Write all declarations to file as Go code
1033 Common Report Var(flag_dump_noaddr)
1034 Suppress output of addresses in debugging dumps
1037 Common Var(flag_dump_passes) Init(0)
1038 Dump optimization passes
1041 Common Report Var(flag_dump_unnumbered)
1042 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1044 fdump-unnumbered-links
1045 Common Report Var(flag_dump_unnumbered_links)
1046 Suppress output of previous and next insn numbers in debugging dumps
1049 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1050 Enable CFI tables via GAS assembler directives.
1053 Common Report Var(flag_early_inlining) Init(1) Optimization
1054 Perform early inlining
1056 feliminate-dwarf2-dups
1057 Common Report Var(flag_eliminate_dwarf2_dups)
1058 Perform DWARF2 duplicate elimination
1061 Common Report Var(flag_ipa_sra) Init(0) Optimization
1062 Perform interprocedural reduction of aggregates
1064 feliminate-unused-debug-symbols
1065 Common Report Var(flag_debug_only_used_symbols)
1066 Perform unused type elimination in debug info
1068 feliminate-unused-debug-types
1069 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1070 Perform unused type elimination in debug info
1072 femit-class-debug-always
1073 Common Report Var(flag_emit_class_debug_always) Init(0)
1074 Do not suppress C++ class debug information.
1077 Common Report Var(flag_exceptions) Optimization
1078 Enable exception handling
1080 fexpensive-optimizations
1081 Common Report Var(flag_expensive_optimizations) Optimization
1082 Perform a number of minor, expensive optimizations
1085 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1086 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1089 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1092 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1095 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1101 Common Var(flag_fat_lto_objects) Init(1)
1102 Output lto objects containing both the intermediate language and binary output.
1105 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1106 Assume no NaNs or infinities are generated
1109 Common Joined RejectNegative Var(common_deferred_options) Defer
1110 -ffixed-<register> Mark <register> as being unavailable to the compiler
1113 Common Report Var(flag_float_store) Optimization
1114 Don't allocate floats and doubles in extended-precision registers
1118 Does nothing. Preserved for backward compatibility.
1121 Common Report Var(flag_forward_propagate) Optimization
1122 Perform a forward propagation pass on RTL
1125 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1126 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1129 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1132 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1134 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1136 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1139 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1141 ; Nonzero means don't put addresses of constant functions in registers.
1142 ; Used for compiling the Unix kernel, where strange substitutions are
1143 ; done on the assembly output.
1145 Common Report Var(flag_no_function_cse,0)
1146 Allow function addresses to be held in registers
1149 Common Report Var(flag_function_sections)
1150 Place each function into its own section
1153 Common Report Var(flag_gcse) Optimization
1154 Perform global common subexpression elimination
1157 Common Report Var(flag_gcse_lm) Init(1) Optimization
1158 Perform enhanced load motion during global common subexpression elimination
1161 Common Report Var(flag_gcse_sm) Init(0) Optimization
1162 Perform store motion after global common subexpression elimination
1165 Common Report Var(flag_gcse_las) Init(0) Optimization
1166 Perform redundant load after store elimination in global common subexpression
1170 Common Report Var(flag_gcse_after_reload) Optimization
1171 Perform global common subexpression elimination after register allocation
1174 ; This option is not documented yet as its semantics will change.
1176 Common Report Var(flag_graphite)
1177 Enable in and out of Graphite representation
1180 Common Report Var(flag_graphite_identity) Optimization
1181 Enable Graphite Identity transformation
1183 floop-parallelize-all
1184 Common Report Var(flag_loop_parallelize_all) Optimization
1185 Mark all loops as parallel
1188 Common Report Var(flag_loop_strip_mine) Optimization
1189 Enable Loop Strip Mining transformation
1192 Common Report Var(flag_loop_interchange) Optimization
1193 Enable Loop Interchange transformation
1196 Common Report Var(flag_loop_block) Optimization
1197 Enable Loop Blocking transformation
1200 Common Report Var(flag_tm)
1201 Enable support for GNU transactional memory
1204 Common Report Var(flag_loop_flatten) Optimization
1205 Enable Loop Flattening transformation
1207 fstrict-volatile-bitfields
1208 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1209 Force bitfield accesses to match their type width
1211 fguess-branch-probability
1212 Common Report Var(flag_guess_branch_prob) Optimization
1213 Enable guessing of branch probabilities
1215 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1216 ; Generate position-independent code for executables if possible
1217 ; On SVR4 targets, it also controls whether or not to emit a
1218 ; string identifying the compiler.
1220 Common Report Var(flag_no_ident,0)
1221 Process #ident directives
1224 Common Report Var(flag_if_conversion) Optimization
1225 Perform conversion of conditional jumps to branchless equivalents
1228 Common Report Var(flag_if_conversion2) Optimization
1229 Perform conversion of conditional jumps to conditional execution
1231 ftree-loop-if-convert
1232 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1233 Convert conditional jumps in innermost loops to branchless equivalents
1235 ftree-loop-if-convert-stores
1236 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1237 Also if-convert conditional jumps containing memory writes
1239 ; -finhibit-size-directive inhibits output of .size for ELF.
1240 ; This is used only for compiling crtstuff.c,
1241 ; and it may be extended to other effects
1242 ; needed for crtstuff.c on other systems.
1243 finhibit-size-directive
1244 Common Report Var(flag_inhibit_size_directive)
1245 Do not generate .size directives
1248 Common Report Var(flag_indirect_inlining)
1249 Perform indirect inlining
1251 ; General flag to enable inlining. Specifying -fno-inline will disable
1252 ; all inlining apart from always-inline functions.
1254 Common Report Var(flag_no_inline,0) Init(0)
1255 Enable inlining of function declared \"inline\", disabling disables all inlining
1257 finline-small-functions
1258 Common Report Var(flag_inline_small_functions) Optimization
1259 Integrate functions into their callers when code size is known not to grow
1262 Common Report Var(flag_inline_functions) Optimization
1263 Integrate functions not declared \"inline\" into their callers when profitable
1265 finline-functions-called-once
1266 Common Report Var(flag_inline_functions_called_once) Optimization
1267 Integrate functions only required by their single caller
1270 Common RejectNegative Joined Alias(finline-limit=)
1273 Common RejectNegative Joined UInteger
1274 -finline-limit=<number> Limit the size of inlined functions to <number>
1277 Common Report Var(flag_inline_atomics) Init(1) Optimization
1278 Inline __atomic operations when a lock free instruction sequence is available.
1280 finstrument-functions
1281 Common Report Var(flag_instrument_function_entry_exit)
1282 Instrument function entry and exit with profiling calls
1284 finstrument-functions-exclude-function-list=
1285 Common RejectNegative Joined
1286 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1288 finstrument-functions-exclude-file-list=
1289 Common RejectNegative Joined
1290 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1293 Common Report Var(flag_ipa_cp) Optimization
1294 Perform Interprocedural constant propagation
1297 Common Report Var(flag_ipa_cp_clone) Optimization
1298 Perform cloning to make Interprocedural constant propagation stronger
1301 Common Report Var(flag_ipa_profile) Init(0) Optimization
1302 Perform interprocedural profile propagation
1305 Common Report Var(flag_ipa_pta) Init(0) Optimization
1306 Perform interprocedural points-to analysis
1309 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1310 Discover pure and const functions
1313 Common Report Var(flag_ipa_reference) Init(0) Optimization
1314 Discover readonly and non addressable static variables
1317 Common Report Var(flag_ipa_matrix_reorg) Optimization
1318 Perform matrix layout flattening and transposing based
1319 on profiling information.
1323 Does nothing. Preserved for backward compatibility.
1326 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1327 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1330 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1333 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1336 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1339 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT)
1340 -fira-region=[one|all|mixed] Set regions for IRA
1343 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1346 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1349 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1352 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1355 Common Report Var(flag_ira_loop_pressure)
1356 Use IRA based register pressure calculation
1357 in RTL loop optimizations.
1359 fira-share-save-slots
1360 Common Report Var(flag_ira_share_save_slots) Init(1)
1361 Share slots for saving different hard registers.
1363 fira-share-spill-slots
1364 Common Report Var(flag_ira_share_spill_slots) Init(1)
1365 Share stack slots for spilled pseudo-registers.
1368 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1369 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1372 Common Report Var(flag_ivopts) Init(1) Optimization
1373 Optimize induction variables on trees
1376 Common Var(flag_jump_tables) Init(1) Optimization
1377 Use jump tables for sufficiently large switch statements
1379 fkeep-inline-functions
1380 Common Report Var(flag_keep_inline_functions)
1381 Generate code for functions even if they are fully inlined
1384 Common Report Var(flag_keep_static_consts) Init(1)
1385 Emit static const variables even if they are not used
1388 Common Report Var(flag_leading_underscore) Init(-1)
1389 Give external symbols a leading underscore
1393 Does nothing. Preserved for backward compatibility.
1397 Enable link-time optimization.
1400 Common RejectNegative Joined Var(flag_lto)
1401 Link-time optimization with number of parallel jobs or jobserver.
1404 Common Var(flag_lto_partition_1to1)
1405 Partition functions and vars at linktime based on object files they originate from
1407 flto-partition=balanced
1408 Common Var(flag_lto_partition_balanced)
1409 Partition functions and vars at linktime into approximately same sized buckets
1412 Common Var(flag_lto_partition_none)
1413 Disable partioning and streaming
1415 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1416 flto-compression-level=
1417 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1418 -flto-compression-level=<number> Use zlib compression level <number> for IL
1421 Common Report Var(flag_lto_report) Init(0)
1422 Report various link-time optimization statistics
1425 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1426 Set errno after built-in math functions
1429 Common Joined RejectNegative UInteger Var(flag_max_errors)
1430 -fmax-errors=<number> Maximum number of errors to report
1433 Common Report Var(mem_report)
1434 Report on permanent memory allocation
1436 ; This will attempt to merge constant section constants, if 1 only
1437 ; string constants and constants from constant pool, if 2 also constant
1439 fmerge-all-constants
1440 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1441 Attempt to merge identical constants and constant variables
1444 Common Report Var(flag_merge_constants,1) Optimization
1445 Attempt to merge identical constants across compilation units
1447 fmerge-debug-strings
1448 Common Report Var(flag_merge_debug_strings) Init(1)
1449 Attempt to merge identical debug strings across compilation units
1452 Common RejectNegative Joined UInteger
1453 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1456 Common Report Var(flag_modulo_sched) Optimization
1457 Perform SMS based modulo scheduling before the first scheduling pass
1459 fmodulo-sched-allow-regmoves
1460 Common Report Var(flag_modulo_sched_allow_regmoves)
1461 Perform SMS based modulo scheduling with register moves allowed
1463 fmove-loop-invariants
1464 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1465 Move loop invariant computations out of loops
1468 Common Var(flag_dce) Init(1) Optimization
1469 Use the RTL dead code elimination pass
1472 Common Var(flag_dse) Init(1) Optimization
1473 Use the RTL dead store elimination pass
1475 freschedule-modulo-scheduled-loops
1476 Common Report Var(flag_resched_modulo_sched) Optimization
1477 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1479 fnon-call-exceptions
1480 Common Report Var(flag_non_call_exceptions) Optimization
1481 Support synchronous non-call exceptions
1484 Common Report Var(flag_omit_frame_pointer) Optimization
1485 When possible do not generate stack frames
1487 foptimize-register-move
1488 Common Report Var(flag_regmove) Optimization
1489 Do the full register move optimization pass
1491 foptimize-sibling-calls
1492 Common Report Var(flag_optimize_sibling_calls) Optimization
1493 Optimize sibling and tail recursive calls
1496 Common Report Var(flag_partial_inlining)
1497 Perform partial inlining
1500 Common Report Var(pre_ipa_mem_report)
1501 Report on memory allocation before interprocedural optimization
1503 fpost-ipa-mem-report
1504 Common Report Var(post_ipa_mem_report)
1505 Report on memory allocation before interprocedural optimization
1508 Common Report Var(flag_pack_struct) Optimization
1509 Pack structure members together without holes
1512 Common RejectNegative Joined UInteger Optimization
1513 -fpack-struct=<number> Set initial maximum structure member alignment
1516 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1517 Return small aggregates in memory, not registers
1520 Common Report Var(flag_peel_loops) Optimization
1521 Perform loop peeling
1524 Common Report Var(flag_no_peephole,0) Optimization
1525 Enable machine specific peephole optimizations
1528 Common Report Var(flag_peephole2) Optimization
1529 Enable an RTL peephole pass before sched2
1532 Common Report Var(flag_pic,2)
1533 Generate position-independent code if possible (large mode)
1536 Common Report Var(flag_pie,2)
1537 Generate position-independent code for executables if possible (large mode)
1540 Common Report Var(flag_pic,1)
1541 Generate position-independent code if possible (small mode)
1544 Common Report Var(flag_pie,1)
1545 Generate position-independent code for executables if possible (small mode)
1548 Common Joined RejectNegative Var(common_deferred_options) Defer
1549 Specify a plugin to load
1552 Common Joined RejectNegative Var(common_deferred_options) Defer
1553 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1555 fpredictive-commoning
1556 Common Report Var(flag_predictive_commoning) Optimization
1557 Run predictive commoning optimization.
1559 fprefetch-loop-arrays
1560 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1561 Generate prefetch instructions, if available, for arrays in loops
1564 Common Report Var(profile_flag)
1565 Enable basic program profiling code
1568 Common Report Var(profile_arc_flag)
1569 Insert arc-based program profiling code
1572 Common Joined RejectNegative Var(profile_data_prefix)
1573 Set the top-level directory for storing the profile data.
1574 The default is 'pwd'.
1577 Common Report Var(flag_profile_correction)
1578 Enable correction of flow inconsistent profile data input
1582 Enable common options for generating profile info for profile feedback directed optimizations
1585 Common Joined RejectNegative
1586 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1589 Common Var(flag_profile_use)
1590 Enable common options for performing profile feedback directed optimizations
1593 Common Joined RejectNegative
1594 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1597 Common Report Var(flag_profile_values)
1598 Insert code to profile values of expressions
1601 Common Var(common_deferred_options) Defer
1604 Common Joined RejectNegative Var(common_deferred_options) Defer
1605 -frandom-seed=<string> Make compile reproducible using <string>
1607 ; This switch causes the command line that was used to create an
1608 ; object file to be recorded into the object file. The exact format
1609 ; of this recording is target and binary file format dependent.
1610 ; It is related to the -fverbose-asm switch, but that switch only
1611 ; records information in the assembler output file as comments, so
1612 ; they never reach the object file.
1613 frecord-gcc-switches
1614 Common Report Var(flag_record_gcc_switches)
1615 Record gcc command line switches in the object file.
1618 Common Report Var(flag_pcc_struct_return,0) Optimization
1619 Return small aggregates in registers
1622 Common Report Var(flag_regmove) Optimization
1623 Enables a register move optimization
1626 Common Report Var(flag_rename_registers) Init(2) Optimization
1627 Perform a register renaming optimization pass
1630 Common Report Var(flag_reorder_blocks) Optimization
1631 Reorder basic blocks to improve code placement
1633 freorder-blocks-and-partition
1634 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1635 Reorder basic blocks and partition into hot and cold sections
1638 Common Report Var(flag_reorder_functions) Optimization
1639 Reorder functions to improve code placement
1641 frerun-cse-after-loop
1642 Common Report Var(flag_rerun_cse_after_loop) Optimization
1643 Add a common subexpression elimination pass after loop optimizations
1647 Does nothing. Preserved for backward compatibility.
1650 Common Report Var(flag_rounding_math) Optimization SetByCombined
1651 Disable optimizations that assume default FP rounding behavior
1654 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1655 Enable scheduling across basic blocks
1658 Common Report Var(flag_sched_pressure) Init(0) Optimization
1659 Enable register pressure sensitive insn scheduling
1662 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1663 Allow speculative motion of non-loads
1666 Common Report Var(flag_schedule_speculative_load) Optimization
1667 Allow speculative motion of some loads
1669 fsched-spec-load-dangerous
1670 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1671 Allow speculative motion of more loads
1674 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1675 -fsched-verbose=<number> Set the verbosity level of the scheduler
1677 fsched2-use-superblocks
1678 Common Report Var(flag_sched2_use_superblocks) Optimization
1679 If scheduling post reload, do superblock scheduling
1683 Does nothing. Preserved for backward compatibility.
1686 Common Report Var(flag_schedule_insns) Optimization
1687 Reschedule instructions before register allocation
1690 Common Report Var(flag_schedule_insns_after_reload) Optimization
1691 Reschedule instructions after register allocation
1693 ; This flag should be on when a target implements non-trivial
1694 ; scheduling hooks, maybe saving some information for its own sake.
1695 ; On IA64, for example, this is used for correct bundling.
1696 fselective-scheduling
1697 Common Report Var(flag_selective_scheduling) Optimization
1698 Schedule instructions using selective scheduling algorithm
1700 fselective-scheduling2
1701 Common Report Var(flag_selective_scheduling2) Optimization
1702 Run selective scheduling after reload
1704 fsel-sched-pipelining
1705 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1706 Perform software pipelining of inner loops during selective scheduling
1708 fsel-sched-pipelining-outer-loops
1709 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1710 Perform software pipelining of outer loops during selective scheduling
1712 fsel-sched-reschedule-pipelined
1713 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1714 Reschedule pipelined regions without pipelining
1716 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1717 ; of stalled insns into the ready list.
1718 fsched-stalled-insns
1719 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1720 Allow premature scheduling of queued insns
1722 fsched-stalled-insns=
1723 Common RejectNegative Joined UInteger
1724 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1726 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1727 ; be examined for a dependency on a stalled insn that is candidate for
1728 ; premature removal from the queue of stalled insns into the ready list (has
1729 ; an effect only if the flag 'sched_stalled_insns' is set).
1730 fsched-stalled-insns-dep
1731 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1732 Set dependence distance checking in premature scheduling of queued insns
1734 fsched-stalled-insns-dep=
1735 Common RejectNegative Joined UInteger
1736 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1738 fsched-group-heuristic
1739 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1740 Enable the group heuristic in the scheduler
1742 fsched-critical-path-heuristic
1743 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1744 Enable the critical path heuristic in the scheduler
1746 fsched-spec-insn-heuristic
1747 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1748 Enable the speculative instruction heuristic in the scheduler
1750 fsched-rank-heuristic
1751 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1752 Enable the rank heuristic in the scheduler
1754 fsched-last-insn-heuristic
1755 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1756 Enable the last instruction heuristic in the scheduler
1758 fsched-dep-count-heuristic
1759 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1760 Enable the dependent count heuristic in the scheduler
1763 Common Report Var(flag_section_anchors) Optimization
1764 Access data in the same section from shared anchor points
1768 Does nothing. Preserved for backward compatibility.
1772 Does nothing. Preserved for backward compatibility.
1775 Common Report Var(flag_ree) Init(0)
1776 Turn on Redundant Extensions Elimination pass.
1779 Common Report Var(flag_show_column) Init(1)
1780 Show column numbers in diagnostics, when available. Default on
1783 Common Report Var(flag_shrink_wrap) Optimization
1784 Emit function prologues only before parts of the function that need it,
1785 rather than at the top of the function.
1788 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1789 Disable optimizations observable by IEEE signaling NaNs
1792 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1793 Disable floating point optimizations that ignore the IEEE signedness of zero
1795 fsingle-precision-constant
1796 Common Report Var(flag_single_precision_constant) Optimization
1797 Convert floating point constants to single precision constants
1799 fsplit-ivs-in-unroller
1800 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1801 Split lifetimes of induction variables when loops are unrolled
1804 Common Report Var(flag_split_stack) Init(-1)
1805 Generate discontiguous stack frames
1808 Common Report Var(flag_split_wide_types) Optimization
1809 Split wide types into independent registers
1811 fvariable-expansion-in-unroller
1812 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1813 Apply variable expansion when loops are unrolled
1816 Common Report RejectNegative Joined
1817 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1820 Common Alias(fstack-check=, specific, no)
1821 Insert stack checking code into the program. Same as -fstack-check=specific
1824 Common Var(common_deferred_options) Defer
1826 fstack-limit-register=
1827 Common RejectNegative Joined Var(common_deferred_options) Defer
1828 -fstack-limit-register=<register> Trap if the stack goes past <register>
1830 fstack-limit-symbol=
1831 Common RejectNegative Joined Var(common_deferred_options) Defer
1832 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1835 Common Report Var(flag_stack_protect, 1)
1836 Use propolice as a stack protection method
1838 fstack-protector-all
1839 Common Report RejectNegative Var(flag_stack_protect, 2)
1840 Use a stack protection method for every function
1843 Common RejectNegative Var(flag_stack_usage)
1844 Output stack usage information on a per-function basis
1848 Does nothing. Preserved for backward compatibility.
1850 ; Nonzero if we should do (language-dependent) alias analysis.
1851 ; Typically, this analysis will assume that expressions of certain
1852 ; types do not alias expressions of certain other types. Only used
1853 ; if alias analysis (in general) is enabled.
1855 Common Report Var(flag_strict_aliasing) Optimization
1856 Assume strict aliasing rules apply
1859 Common Report Var(flag_strict_overflow)
1860 Treat signed overflow as undefined
1863 Common Report Var(flag_syntax_only)
1864 Check for syntax errors, then stop
1867 Common Report Var(flag_test_coverage)
1868 Create data files needed by \"gcov\"
1871 Common Report Var(flag_thread_jumps) Optimization
1872 Perform jump threading optimizations
1875 Common Report Var(time_report)
1876 Report the time taken by each compiler pass
1879 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
1880 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
1883 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
1886 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
1889 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
1892 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
1895 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
1898 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1899 Reorder top level functions, variables, and asms
1902 Common Report Var(flag_tracer)
1903 Perform superblock formation via tail duplication
1905 ; Zero means that floating-point math operations cannot generate a
1906 ; (user-visible) trap. This is the case, for example, in nonstop
1907 ; IEEE 754 arithmetic.
1909 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
1910 Assume floating-point operations can trap
1913 Common Report Var(flag_trapv) Optimization
1914 Trap for signed overflow in addition, subtraction and multiplication
1917 Common Report Var(flag_tree_ccp) Optimization
1918 Enable SSA-CCP optimization on trees
1921 Common Report Var(flag_tree_bit_ccp) Optimization
1922 Enable SSA-BIT-CCP optimization on trees
1926 Does nothing. Preserved for backward compatibility.
1929 Common Report Var(flag_tree_ch) Optimization
1930 Enable loop header copying on trees
1933 Common Report Var(flag_tree_copyrename) Optimization
1934 Replace SSA temporaries with better names in copies
1937 Common Report Var(flag_tree_copy_prop) Optimization
1938 Enable copy propagation on trees
1940 ftree-store-copy-prop
1942 Does nothing. Preserved for backward compatibility.
1945 Common Report Var(flag_tree_cselim) Init(2) Optimization
1946 Transform condition stores into unconditional ones
1948 ftree-switch-conversion
1949 Common Report Var(flag_tree_switch_conversion) Optimization
1950 Perform conversions of switch initializations.
1953 Common Report Var(flag_tree_dce) Optimization
1954 Enable SSA dead code elimination optimization on trees
1956 ftree-dominator-opts
1957 Common Report Var(flag_tree_dom) Optimization
1958 Enable dominator optimizations
1961 Common Report Var(flag_tree_tail_merge) Optimization
1962 Enable tail merging on trees
1965 Common Report Var(flag_tree_dse) Optimization
1966 Enable dead store elimination
1969 Common Report Var(flag_tree_forwprop) Init(1) Optimization
1970 Enable forward propagation on trees
1973 Common Report Var(flag_tree_fre) Optimization
1974 Enable Full Redundancy Elimination (FRE) on trees
1977 Common Report Var(flag_optimize_strlen) Optimization
1978 Enable string length optimizations on trees
1980 ftree-loop-distribution
1981 Common Report Var(flag_tree_loop_distribution) Optimization
1982 Enable loop distribution on trees
1984 ftree-loop-distribute-patterns
1985 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
1986 Enable loop distribution for patterns transformed into a library call
1989 Common Report Var(flag_tree_loop_im) Init(1) Optimization
1990 Enable loop invariant motion on trees
1993 Common Alias(floop-interchange)
1994 Enable loop interchange transforms. Same as -floop-interchange
1997 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
1998 Create canonical induction variables in loops
2001 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2002 Enable loop optimizations on tree level
2004 ftree-parallelize-loops=
2005 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2006 Enable automatic parallelization of loops
2009 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2010 Enable hoisting loads from conditional pointers.
2013 Common Report Var(flag_tree_pre) Optimization
2014 Enable SSA-PRE optimization on trees
2017 Common Report Var(flag_tree_pta) Init(1) Optimization
2018 Perform function-local points-to analysis on trees.
2021 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2022 Enable reassociation on tree level
2026 Does nothing. Preserved for backward compatibility.
2029 Common Report Var(flag_tree_sink) Optimization
2030 Enable SSA code sinking on trees
2033 Common Report Var(flag_tree_sra) Optimization
2034 Perform scalar replacement of aggregates
2037 Common Report Var(flag_tree_ter) Optimization
2038 Replace temporary expressions in the SSA->normal pass
2041 Common Report Var(flag_tree_live_range_split) Optimization
2042 Perform live range splitting during the SSA->normal pass
2045 Common Report Var(flag_tree_vrp) Init(0) Optimization
2046 Perform Value Range Propagation on trees
2049 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2050 Compile whole compilation unit at a time
2053 Common Report Var(flag_unroll_loops) Optimization
2054 Perform loop unrolling when iteration count is known
2057 Common Report Var(flag_unroll_all_loops) Optimization
2058 Perform loop unrolling for all loops
2060 ; Nonzero means that loop optimizer may assume that the induction variables
2061 ; that control loops do not overflow and that the loops with nontrivial
2062 ; exit condition are not infinite
2063 funsafe-loop-optimizations
2064 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2065 Allow loop optimizations to assume that the loops behave in normal way
2068 Common Report Var(flag_associative_math) SetByCombined
2069 Allow optimization for floating-point arithmetic which may change the
2070 result of the operation due to rounding.
2073 Common Report Var(flag_reciprocal_math) SetByCombined
2074 Same as -fassociative-math for expressions which include division.
2076 ; Nonzero means that unsafe floating-point math optimizations are allowed
2077 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2078 ; are allowed to assume that their arguments and results are "normal"
2079 ; (e.g., nonnegative for SQRT).
2080 funsafe-math-optimizations
2081 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2082 Allow math optimizations that may violate IEEE or ISO standards
2085 Common Report Var(flag_unswitch_loops) Optimization
2086 Perform loop unswitching
2089 Common Report Var(flag_unwind_tables) Optimization
2090 Just generate unwind tables for exception handling
2095 ; Positive if we should track variables, negative if we should run
2096 ; the var-tracking pass only to discard debug annotations, zero if
2097 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2098 ; will be set according to optimize, debug_info_level and debug_hooks
2099 ; in process_options ().
2101 Common Report Var(flag_var_tracking) Init(2) Optimization
2102 Perform variable tracking
2104 ; Positive if we should track variables at assignments, negative if
2105 ; we should run the var-tracking pass only to discard debug
2106 ; annotations. When flag_var_tracking_assignments ==
2107 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2108 fvar-tracking-assignments
2109 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2110 Perform variable tracking by annotating assignments
2112 ; Nonzero if we should toggle flag_var_tracking_assignments after
2113 ; processing options and computing its default. */
2114 fvar-tracking-assignments-toggle
2115 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2116 Toggle -fvar-tracking-assignments
2118 ; Positive if we should track uninitialized variables, negative if
2119 ; we should run the var-tracking pass only to discard debug
2120 ; annotations. When flag_var_tracking_uninit == AUTODETECT_VALUE it
2121 ; will be set according to flag_var_tracking.
2122 fvar-tracking-uninit
2123 Common Report Var(flag_var_tracking_uninit) Optimization
2124 Perform variable tracking and also tag variables that are uninitialized
2127 Common Report Var(flag_tree_vectorize) Optimization
2128 Enable loop vectorization on trees
2131 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2132 Enable basic block vectorization (SLP) on trees
2135 Common Report Var(flag_vect_cost_model) Optimization
2136 Enable use of cost model in vectorization
2138 ftree-vect-loop-version
2139 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2140 Enable loop versioning when doing loop vectorization on trees
2142 ftree-vectorizer-verbose=
2143 Common RejectNegative Joined UInteger
2144 -ftree-vectorizer-verbose=<number> Set the verbosity level of the vectorizer
2147 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2148 Enable copy propagation of scalar-evolution information.
2150 ; -fverbose-asm causes extra commentary information to be produced in
2151 ; the generated assembly code (to make it more readable). This option
2152 ; is generally only of use to those who actually need to read the
2153 ; generated assembly code (perhaps while debugging the compiler itself).
2154 ; -fno-verbose-asm, the default, causes the extra information
2155 ; to not be added and is useful when comparing two assembler files.
2157 Common Report Var(flag_verbose_asm)
2158 Add extra commentary to assembler output
2161 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2162 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2165 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2168 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2171 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2174 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2177 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2180 Common Report Var(flag_value_profile_transformations) Optimization
2181 Use expression value profiles in optimizations
2184 Common Report Var(flag_web) Init(2) Optimization
2185 Construct webs and split unrelated uses of single variable
2187 ftree-builtin-call-dce
2188 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2189 Enable conditional dead code elimination for builtin calls
2192 Common Report Var(flag_whole_program) Init(0) Optimization
2193 Perform whole program optimizations
2196 Common Report Var(flag_wrapv) Optimization
2197 Assume signed arithmetic overflow wraps around
2199 fzero-initialized-in-bss
2200 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2201 Put zero initialized data in the bss section
2204 Common JoinedOrMissing
2205 Generate debug information in default format
2208 Common JoinedOrMissing Negative(gdwarf-)
2209 Generate debug information in COFF format
2212 Common Joined UInteger Var(dwarf_version) Init(2) Negative(gstabs)
2213 Generate debug information in DWARF v2 (or later) format
2216 Common JoinedOrMissing
2217 Generate debug information in default extended format
2219 gno-record-gcc-switches
2220 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(0)
2221 Don't record gcc command line switches in DWARF DW_AT_producer.
2223 grecord-gcc-switches
2224 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2225 Record gcc command line switches in DWARF DW_AT_producer.
2228 Common JoinedOrMissing Negative(gstabs+)
2229 Generate debug information in STABS format
2232 Common JoinedOrMissing Negative(gvms)
2233 Generate debug information in extended STABS format
2236 Common RejectNegative Var(dwarf_strict,0) Init(-1)
2237 Emit DWARF additions beyond selected version
2240 Common Report RejectNegative Var(dwarf_strict,1)
2241 Don't emit DWARF additions beyond selected version
2244 Common Report Var(flag_gtoggle)
2245 Toggle debug information generation
2248 Common JoinedOrMissing Negative(gxcoff)
2249 Generate debug information in VMS format
2252 Common JoinedOrMissing Negative(gxcoff+)
2253 Generate debug information in XCOFF format
2256 Common JoinedOrMissing Negative(gcoff)
2257 Generate debug information in extended XCOFF format
2260 Driver Joined Separate
2263 Common Joined Var(plugindir_string) Init(0)
2264 -iplugindir=<dir> Set <dir> to be the default plugin directory
2267 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2268 -imultiarch <dir> Set <dir> to be the multiarch include subdirectory
2271 Driver Joined Separate
2276 no-canonical-prefixes
2289 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2290 -o <file> Place output into <file>
2293 Common Var(profile_flag)
2294 Enable function profiling
2297 Driver Var(pass_exit_codes)
2300 Common Var(pedantic)
2301 Issue warnings needed for strict compliance to the standard
2304 Common Var(flag_pedantic_errors)
2305 Like -pedantic but issue them as errors
2311 Driver Var(use_pipes)
2314 Driver JoinedOrMissing Var(print_file_name)
2316 print-libgcc-file-name
2319 print-multi-directory
2320 Driver Var(print_multi_directory)
2323 Driver Var(print_multi_lib)
2325 print-multi-os-directory
2326 Driver Var(print_multi_os_directory)
2329 Driver Var(print_multiarch)
2332 Driver JoinedOrMissing Var(print_prog_name)
2335 Driver Var(print_search_dirs)
2338 Driver Var(print_sysroot)
2340 print-sysroot-headers-suffix
2341 Driver Var(print_sysroot_headers_suffix)
2344 Common Var(quiet_flag) RejectDriver
2345 Do not display functions compiled or elapsed time
2363 Driver Var(report_times)
2366 Driver JoinedOrMissing
2369 Driver Joined Separate
2373 ; C option, but driver must not handle as "-u ndef".
2376 Common Driver Var(verbose_flag)
2377 Enable verbose output
2380 Common Var(version_flag) RejectDriver
2381 Display the compiler's version
2384 Common Var(inhibit_warnings)
2388 Driver Separate Var(wrapper_string)
2391 Driver Joined Separate
2394 Driver RejectNegative Negative(pie)
2395 Create a shared library
2401 Driver Separate Alias(specs=)
2414 ; Documented for Fortran, but always accepted by driver.
2421 ; Documented for Go, but always accepted by driver.
2427 Driver RejectNegative Negative(shared)
2428 Create a position independent executable
2431 Driver Joined Separate
2433 ; This comment is to ensure we retain the blank line above.