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 Separate Alias(print-prog-name=)
352 Driver JoinedOrMissing Alias(print-prog-name=)
355 Driver Alias(print-search-dirs)
358 Driver Alias(print-sysroot)
360 -print-sysroot-headers-suffix
361 Driver Alias(print-sysroot-headers-suffix)
367 Driver Alias(save-temps)
373 Driver Separate Alias(specs=)
376 Driver Joined Alias(specs=)
382 Driver Alias(symbolic)
386 Alias for --help=target
394 ;; The driver used to convert options such as --help into forms such
395 ;; as -fhelp; the following four entries are for compatibility with
396 ;; any direct uses of those (undocumented) -f forms
398 Common Driver Alias(-help)
401 Common Driver Joined Alias(-help=)
404 Common Driver Alias(-target-help)
407 Common Driver Alias(-version)
411 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
414 Common Joined Alias(-param)
417 Driver Separate Alias(-sysroot=)
420 Driver JoinedOrMissing
426 Driver Joined Separate
432 Driver Joined Separate
438 Common JoinedOrMissing Optimization
439 -O<number> Set optimization level to <number>
443 Optimize for space rather than speed
447 Optimize for speed disregarding exact standards compliance
459 Driver Joined Separate
465 Driver Joined Separate
486 Common RejectNegative Warning Alias(Wextra)
487 This switch is deprecated; use -Wextra instead
490 Driver JoinedOrMissing
493 Driver JoinedOrMissing
496 Driver JoinedOrMissing
499 Common Var(warn_aggregate_return) Warning
500 Warn about returning structures, unions or arrays
503 Common Var(warn_array_bounds) Warning
504 Warn if an array is accessed out of bounds
507 Common Var(warn_attributes) Init(1) Warning
508 Warn about inappropriate attribute usage
511 Common Var(warn_cast_align) Warning
512 Warn about pointer casts which increase alignment
515 Common Var(warn_cpp) Init(1) Warning
516 Warn when a #warning directive is encountered
518 Wdeprecated-declarations
519 Common Var(warn_deprecated_decl) Init(1) Warning
520 Warn about uses of __attribute__((deprecated)) declarations
522 Wdisabled-optimization
523 Common Var(warn_disabled_optimization) Warning
524 Warn when an optimization pass is disabled
527 Common Var(warnings_are_errors)
528 Treat all warnings as errors
532 Treat specified warning as error
535 Common Var(extra_warnings) Warning
536 Print extra (possibly unwanted) warnings
539 Common Var(flag_fatal_errors)
540 Exit on the first error occurred
543 Common RejectNegative Joined UInteger
544 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
547 Common Var(warn_free_nonheap_object) Init(1) Warning
548 Warn when attempting to free a non-heap object
551 Common Var(warn_inline) Warning
552 Warn when an inlined function cannot be inlined
554 Winvalid-memory-model
555 Common Var(warn_invalid_memory_model) Init(1) Warning
556 Warn when an atomic memory model parameter is known to be outside the valid range.
559 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
562 Common RejectNegative Joined UInteger Warning
563 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
565 Wunsafe-loop-optimizations
566 Common Var(warn_unsafe_loop_optimizations) Warning
567 Warn if the loop cannot be optimized due to nontrivial assumptions.
570 Common Var(warn_missing_noreturn) Warning
571 Warn about functions which might be candidates for __attribute__((noreturn))
574 Common Var(warn_overflow) Init(1) Warning
575 Warn about overflow in arithmetic expressions
578 Common Var(warn_packed) Warning
579 Warn when the packed attribute has no effect on struct layout
582 Common Var(warn_padded) Warning
583 Warn when padding is required to align structure members
586 Common Var(warn_shadow) Warning
587 Warn when one local variable shadows another
590 Common Var(warn_stack_protect) Warning
591 Warn when not issuing stack smashing protection for some reason
594 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
595 Warn if stack usage might be larger than specified amount
599 Warn about code which might break strict aliasing rules
602 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Init(-1) Warning
603 Warn about code which might break strict aliasing rules
607 Warn about optimizations that assume that signed overflow is undefined
610 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Init(-1) Warning
611 Warn about optimizations that assume that signed overflow is undefined
613 Wsuggest-attribute=const
614 Common Var(warn_suggest_attribute_const) Warning
615 Warn about functions which might be candidates for __attribute__((const))
617 Wsuggest-attribute=pure
618 Common Var(warn_suggest_attribute_pure) Warning
619 Warn about functions which might be candidates for __attribute__((pure))
621 Wsuggest-attribute=noreturn
622 Common Var(warn_suggest_attribute_noreturn) Warning
623 Warn about functions which might be candidates for __attribute__((noreturn))
626 Common Var(warn_switch) Warning
627 Warn about enumerated switches, with no default, missing a case
630 Common Var(warn_switch_default) Warning
631 Warn about enumerated switches missing a \"default:\" statement
634 Common Var(warn_switch_enum) Warning
635 Warn about all enumerated switches missing a specific case
638 Common Var(warn_system_headers) Warning
639 Do not suppress warnings from system headers
642 Common Var(warn_trampolines) Warning
643 Warn whenever a trampoline is generated
646 Common Var(warn_type_limits) Init(-1) Warning
647 Warn if a comparison is always true or always false due to the limited range of the data type
650 Common Var(warn_uninitialized) Init(-1) Warning
651 Warn about uninitialized automatic variables
654 Common Var(warn_maybe_uninitialized) Warning
655 Warn about maybe uninitialized automatic variables
659 Does nothing. Preserved for backward compatibility.
662 Common Var(warn_unused) Init(0) Warning
663 Enable all -Wunused- warnings
665 Wunused-but-set-parameter
666 Common Var(warn_unused_but_set_parameter) Init(-1) Warning
667 Warn when a function parameter is only set, otherwise unused
669 Wunused-but-set-variable
670 Common Var(warn_unused_but_set_variable) Init(-1) Warning
671 Warn when a variable is only set, otherwise unused
674 Common Var(warn_unused_function) Init(-1) Warning
675 Warn when a function is unused
678 Common Var(warn_unused_label) Init(-1) Warning
679 Warn when a label is unused
682 Common Var(warn_unused_parameter) Init(-1) Warning
683 Warn when a function parameter is unused
686 Common Var(warn_unused_value) Init(-1) Warning
687 Warn when an expression value is unused
690 Common Var(warn_unused_variable) Init(-1) Warning
691 Warn when a variable is unused
694 Common Var(warn_coverage_mismatch) Init(1) Warning
695 Warn in case profiles in -fprofile-use do not match
697 Wvector-operation-performance
698 Common Var(warn_vector_operation_performance) Warning
699 Warn when a vector operation is compiled outside the SIMD
714 Common Separate Var(aux_info_file_name)
715 -aux-info <file> Emit declaration information into <file>
718 Common Joined Alias(aux-info)
721 Common Separate RejectDriver Var(aux_base_name)
724 Common Separate RejectDriver
734 -d<letters> Enable dumps from specific passes of the compiler
737 Common Separate Var(dump_base_name)
738 -dumpbase <file> Set the file basename to be used for dumps
741 Common Separate Var(dump_dir_name)
742 -dumpdir <dir> Set the directory name to be used for dumps
754 Driver Joined Separate
756 ; This option has historically been passed down to the linker by an
757 ; accident of a %{e*} spec, so ensure it continues to be passed down
758 ; as a single option. The supported option for this purpose is
759 ; -rdynamic. See PR 47390.
763 ; The version of the C++ ABI in use. The following values are allowed:
765 ; 0: The version of the ABI believed most conformant with the C++ ABI
766 ; specification. This ABI may change as bugs are discovered and fixed.
767 ; Therefore, 0 will not necessarily indicate the same ABI in different
770 ; 1: The version of the ABI first used in G++ 3.2.
772 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
774 ; 3: The version of the ABI that fixes the missing underscore
775 ; in template non-type arguments of pointer type.
777 ; 4: The version of the ABI that introduces unambiguous mangling of
778 ; vector types. First selectable in G++ 4.5.
780 ; 5: The version of the ABI that ignores attribute const/noreturn
781 ; in function pointer mangling, and corrects mangling of decltype and
782 ; function parameters used in other parameters and the return type.
783 ; First selectable in G++ 4.6.
785 ; 6: The version of the ABI that doesn't promote scoped enums to int and
786 ; changes the mangling of template argument packs, const/static_cast,
787 ; prefix ++ and --, and a class scope function used as a template
789 ; First selectable in G++ 4.7.
791 ; Additional positive integers will be assigned as new versions of
792 ; the ABI become the default version of the ABI.
794 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
797 Common Report Var(align_functions,0) Optimization UInteger
798 Align the start of functions
801 Common RejectNegative Joined UInteger Var(align_functions)
804 Common Report Var(align_jumps,0) Optimization UInteger
805 Align labels which are only reached by jumping
808 Common RejectNegative Joined UInteger Var(align_jumps)
811 Common Report Var(align_labels,0) Optimization UInteger
815 Common RejectNegative Joined UInteger Var(align_labels)
818 Common Report Var(align_loops,0) Optimization UInteger
819 Align the start of loops
822 Common RejectNegative Joined UInteger Var(align_loops)
826 Does nothing. Preserved for backward compatibility.
830 Does nothing. Preserved for backward compatibility.
832 fargument-noalias-global
834 Does nothing. Preserved for backward compatibility.
836 fargument-noalias-anything
838 Does nothing. Preserved for backward compatibility.
840 fasynchronous-unwind-tables
841 Common Report Var(flag_asynchronous_unwind_tables) Optimization
842 Generate unwind tables that are exact at each instruction boundary
845 Common Report Var(flag_auto_inc_dec) Init(1)
846 Generate auto-inc/dec instructions
848 ; -fcheck-bounds causes gcc to generate array bounds checks.
849 ; For C, C++ and ObjC: defaults off.
850 ; For Java: defaults to on.
851 ; For Fortran: defaults to off.
853 Common Report Var(flag_bounds_check)
854 Generate code to check bounds before indexing arrays
857 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
858 Replace add, compare, branch with branch on count register
860 fbranch-probabilities
861 Common Report Var(flag_branch_probabilities) Optimization
862 Use profiling information for branch probabilities
864 fbranch-target-load-optimize
865 Common Report Var(flag_branch_target_load_optimize) Optimization
866 Perform branch target load optimization before prologue / epilogue threading
868 fbranch-target-load-optimize2
869 Common Report Var(flag_branch_target_load_optimize2) Optimization
870 Perform branch target load optimization after prologue / epilogue threading
873 Common Report Var(flag_btr_bb_exclusive) Optimization
874 Restrict target load migration not to re-use registers in any basic block
877 Common Joined RejectNegative Var(common_deferred_options) Defer
878 -fcall-saved-<register> Mark <register> as being preserved across functions
881 Common Joined RejectNegative Var(common_deferred_options) Defer
882 -fcall-used-<register> Mark <register> as being corrupted by function calls
884 ; Nonzero for -fcaller-saves: allocate values in regs that need to
885 ; be saved across function calls, if that produces overall better code.
886 ; Optional now, so people can test it.
888 Common Report Var(flag_caller_saves) Optimization
889 Save registers around function calls
892 Common Report Var(flag_check_data_deps)
893 Compare the results of several data dependence analyzers.
895 fcombine-stack-adjustments
896 Common Report Var(flag_combine_stack_adjustments) Optimization
897 Looks for opportunities to reduce stack adjustments and stack references.
900 Common Report Var(flag_no_common,0) Optimization
901 Do not put uninitialized globals in the common section
905 ; Converted by the driver to -fcompare-debug= options.
908 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
909 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
911 fcompare-debug-second
912 Common Driver RejectNegative Var(flag_compare_debug)
913 Run only the second compilation of -fcompare-debug
916 Common Report Var(flag_compare_elim_after_reload) Optimization
917 Perform comparison elimination after register allocation has finished
920 Common Var(flag_conserve_stack) Optimization
921 Do not perform optimizations increasing noticeably stack usage
924 Common Report Var(flag_cprop_registers) Optimization
925 Perform a register copy-propagation optimization pass
928 Common Report Var(flag_crossjumping) Optimization
929 Perform cross-jumping optimization
932 Common Report Var(flag_cse_follow_jumps) Optimization
933 When running CSE, follow jumps to their targets
937 Does nothing. Preserved for backward compatibility.
940 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
941 Omit range reduction step when performing complex division
944 Common Report Var(flag_cx_fortran_rules) Optimization
945 Complex multiplication and division follow Fortran rules
948 Common Report Var(flag_data_sections) Optimization
949 Place data items into their own section
952 Common Report Var(common_deferred_options) Defer
953 List all available debugging counters with their limits and counts.
956 Common RejectNegative Joined Var(common_deferred_options) Defer
957 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
960 Common Joined RejectNegative Var(common_deferred_options) Defer
961 Map one directory name to another in debug information
964 Common Report Var(flag_debug_types_section) Init(1)
965 Output .debug_types section when using DWARF v4 debuginfo.
967 ; Nonzero for -fdefer-pop: don't pop args after each function call
968 ; instead save them up to pop many calls' args with one insns.
970 Common Report Var(flag_defer_pop) Optimization
971 Defer popping functions args from stack until later
974 Common Report Var(flag_delayed_branch) Optimization
975 Attempt to fill delay slots of branch instructions
977 fdelete-null-pointer-checks
978 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
979 Delete useless null pointer checks
982 Common Report Var(flag_devirtualize) Optimization
983 Try to convert virtual calls to direct ones.
985 fdiagnostics-show-location=
986 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
987 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
989 ; Required for these enum values.
994 Name(diagnostic_prefixing_rule) Type(int)
997 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1000 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1002 fdiagnostics-show-option
1003 Common Var(flag_diagnostics_show_option) Init(1)
1004 Amend appropriate diagnostic messages with the command line option that controls them
1007 Common Joined RejectNegative Var(common_deferred_options) Defer
1008 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1011 Common Joined RejectNegative Var(common_deferred_options) Defer
1012 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1015 Common Joined RejectNegative Var(common_deferred_options) Defer
1016 -fdump-<type> Dump various compiler internals to a file
1019 Driver RejectNegative
1022 Common RejectNegative Joined Var(flag_dump_final_insns)
1023 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1026 Common RejectNegative Joined Var(flag_dump_go_spec)
1027 -fdump-go-spec=filename Write all declarations to file as Go code
1030 Common Report Var(flag_dump_noaddr)
1031 Suppress output of addresses in debugging dumps
1034 Common Var(flag_dump_passes) Init(0)
1035 Dump optimization passes
1038 Common Report Var(flag_dump_unnumbered)
1039 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1041 fdump-unnumbered-links
1042 Common Report Var(flag_dump_unnumbered_links)
1043 Suppress output of previous and next insn numbers in debugging dumps
1046 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1047 Enable CFI tables via GAS assembler directives.
1050 Common Report Var(flag_early_inlining) Init(1) Optimization
1051 Perform early inlining
1053 feliminate-dwarf2-dups
1054 Common Report Var(flag_eliminate_dwarf2_dups)
1055 Perform DWARF2 duplicate elimination
1058 Common Report Var(flag_ipa_sra) Init(0) Optimization
1059 Perform interprocedural reduction of aggregates
1061 feliminate-unused-debug-symbols
1062 Common Report Var(flag_debug_only_used_symbols)
1063 Perform unused type elimination in debug info
1065 feliminate-unused-debug-types
1066 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1067 Perform unused type elimination in debug info
1069 femit-class-debug-always
1070 Common Report Var(flag_emit_class_debug_always) Init(0)
1071 Do not suppress C++ class debug information.
1074 Common Report Var(flag_exceptions) Optimization
1075 Enable exception handling
1077 fexpensive-optimizations
1078 Common Report Var(flag_expensive_optimizations) Optimization
1079 Perform a number of minor, expensive optimizations
1082 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1083 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1086 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1089 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1092 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1098 Common Var(flag_fat_lto_objects) Init(1)
1099 Output lto objects containing both the intermediate language and binary output.
1102 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1103 Assume no NaNs or infinities are generated
1106 Common Joined RejectNegative Var(common_deferred_options) Defer
1107 -ffixed-<register> Mark <register> as being unavailable to the compiler
1110 Common Report Var(flag_float_store) Optimization
1111 Don't allocate floats and doubles in extended-precision registers
1115 Does nothing. Preserved for backward compatibility.
1118 Common Report Var(flag_forward_propagate) Optimization
1119 Perform a forward propagation pass on RTL
1122 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1123 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1126 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1129 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1131 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1133 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1136 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1138 ; Nonzero means don't put addresses of constant functions in registers.
1139 ; Used for compiling the Unix kernel, where strange substitutions are
1140 ; done on the assembly output.
1142 Common Report Var(flag_no_function_cse,0)
1143 Allow function addresses to be held in registers
1146 Common Report Var(flag_function_sections)
1147 Place each function into its own section
1150 Common Report Var(flag_gcse) Optimization
1151 Perform global common subexpression elimination
1154 Common Report Var(flag_gcse_lm) Init(1) Optimization
1155 Perform enhanced load motion during global common subexpression elimination
1158 Common Report Var(flag_gcse_sm) Init(0) Optimization
1159 Perform store motion after global common subexpression elimination
1162 Common Report Var(flag_gcse_las) Init(0) Optimization
1163 Perform redundant load after store elimination in global common subexpression
1167 Common Report Var(flag_gcse_after_reload) Optimization
1168 Perform global common subexpression elimination after register allocation
1171 ; This option is not documented yet as its semantics will change.
1173 Common Report Var(flag_graphite)
1174 Enable in and out of Graphite representation
1177 Common Report Var(flag_graphite_identity) Optimization
1178 Enable Graphite Identity transformation
1180 floop-parallelize-all
1181 Common Report Var(flag_loop_parallelize_all) Optimization
1182 Mark all loops as parallel
1185 Common Report Var(flag_loop_strip_mine) Optimization
1186 Enable Loop Strip Mining transformation
1189 Common Report Var(flag_loop_interchange) Optimization
1190 Enable Loop Interchange transformation
1193 Common Report Var(flag_loop_block) Optimization
1194 Enable Loop Blocking transformation
1197 Common Report Var(flag_tm)
1198 Enable support for GNU transactional memory
1201 Common Report Var(flag_loop_flatten) Optimization
1202 Enable Loop Flattening transformation
1204 fstrict-volatile-bitfields
1205 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1206 Force bitfield accesses to match their type width
1208 fguess-branch-probability
1209 Common Report Var(flag_guess_branch_prob) Optimization
1210 Enable guessing of branch probabilities
1212 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1213 ; Generate position-independent code for executables if possible
1214 ; On SVR4 targets, it also controls whether or not to emit a
1215 ; string identifying the compiler.
1217 Common Report Var(flag_no_ident,0)
1218 Process #ident directives
1221 Common Report Var(flag_if_conversion) Optimization
1222 Perform conversion of conditional jumps to branchless equivalents
1225 Common Report Var(flag_if_conversion2) Optimization
1226 Perform conversion of conditional jumps to conditional execution
1228 ftree-loop-if-convert
1229 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1230 Convert conditional jumps in innermost loops to branchless equivalents
1232 ftree-loop-if-convert-stores
1233 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1234 Also if-convert conditional jumps containing memory writes
1236 ; -finhibit-size-directive inhibits output of .size for ELF.
1237 ; This is used only for compiling crtstuff.c,
1238 ; and it may be extended to other effects
1239 ; needed for crtstuff.c on other systems.
1240 finhibit-size-directive
1241 Common Report Var(flag_inhibit_size_directive)
1242 Do not generate .size directives
1245 Common Report Var(flag_indirect_inlining)
1246 Perform indirect inlining
1248 ; General flag to enable inlining. Specifying -fno-inline will disable
1249 ; all inlining apart from always-inline functions.
1251 Common Report Var(flag_no_inline,0) Init(0)
1252 Enable inlining of function declared \"inline\", disabling disables all inlining
1254 finline-small-functions
1255 Common Report Var(flag_inline_small_functions) Optimization
1256 Integrate functions into their callers when code size is known not to grow
1259 Common Report Var(flag_inline_functions) Optimization
1260 Integrate functions not declared \"inline\" into their callers when profitable
1262 finline-functions-called-once
1263 Common Report Var(flag_inline_functions_called_once) Optimization
1264 Integrate functions only required by their single caller
1267 Common RejectNegative Joined Alias(finline-limit=)
1270 Common RejectNegative Joined UInteger
1271 -finline-limit=<number> Limit the size of inlined functions to <number>
1274 Common Report Var(flag_inline_atomics) Init(1) Optimization
1275 Inline __atomic operations when a lock free instruction sequence is available.
1277 finstrument-functions
1278 Common Report Var(flag_instrument_function_entry_exit)
1279 Instrument function entry and exit with profiling calls
1281 finstrument-functions-exclude-function-list=
1282 Common RejectNegative Joined
1283 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1285 finstrument-functions-exclude-file-list=
1286 Common RejectNegative Joined
1287 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1290 Common Report Var(flag_ipa_cp) Optimization
1291 Perform Interprocedural constant propagation
1294 Common Report Var(flag_ipa_cp_clone) Optimization
1295 Perform cloning to make Interprocedural constant propagation stronger
1298 Common Report Var(flag_ipa_profile) Init(0) Optimization
1299 Perform interprocedural profile propagation
1302 Common Report Var(flag_ipa_pta) Init(0) Optimization
1303 Perform interprocedural points-to analysis
1306 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1307 Discover pure and const functions
1310 Common Report Var(flag_ipa_reference) Init(0) Optimization
1311 Discover readonly and non addressable static variables
1314 Common Report Var(flag_ipa_matrix_reorg) Optimization
1315 Perform matrix layout flattening and transposing based
1316 on profiling information.
1320 Does nothing. Preserved for backward compatibility.
1323 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1324 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1327 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1330 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1333 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1336 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT)
1337 -fira-region=[one|all|mixed] Set regions for IRA
1340 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1343 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1346 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1349 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1352 Common Report Var(flag_ira_loop_pressure)
1353 Use IRA based register pressure calculation
1354 in RTL loop optimizations.
1356 fira-share-save-slots
1357 Common Report Var(flag_ira_share_save_slots) Init(1)
1358 Share slots for saving different hard registers.
1360 fira-share-spill-slots
1361 Common Report Var(flag_ira_share_spill_slots) Init(1)
1362 Share stack slots for spilled pseudo-registers.
1365 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1366 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1369 Common Report Var(flag_ivopts) Init(1) Optimization
1370 Optimize induction variables on trees
1373 Common Var(flag_jump_tables) Init(1) Optimization
1374 Use jump tables for sufficiently large switch statements
1376 fkeep-inline-functions
1377 Common Report Var(flag_keep_inline_functions)
1378 Generate code for functions even if they are fully inlined
1381 Common Report Var(flag_keep_static_consts) Init(1)
1382 Emit static const variables even if they are not used
1385 Common Report Var(flag_leading_underscore) Init(-1)
1386 Give external symbols a leading underscore
1390 Does nothing. Preserved for backward compatibility.
1394 Enable link-time optimization.
1397 Common RejectNegative Joined Var(flag_lto)
1398 Link-time optimization with number of parallel jobs or jobserver.
1401 Common Var(flag_lto_partition_1to1)
1402 Partition functions and vars at linktime based on object files they originate from
1404 flto-partition=balanced
1405 Common Var(flag_lto_partition_balanced)
1406 Partition functions and vars at linktime into approximately same sized buckets
1409 Common Var(flag_lto_partition_none)
1410 Disable partioning and streaming
1412 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1413 flto-compression-level=
1414 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1415 -flto-compression-level=<number> Use zlib compression level <number> for IL
1418 Common Report Var(flag_lto_report) Init(0)
1419 Report various link-time optimization statistics
1422 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1423 Set errno after built-in math functions
1426 Common Joined RejectNegative UInteger Var(flag_max_errors)
1427 -fmax-errors=<number> Maximum number of errors to report
1430 Common Report Var(mem_report)
1431 Report on permanent memory allocation
1433 ; This will attempt to merge constant section constants, if 1 only
1434 ; string constants and constants from constant pool, if 2 also constant
1436 fmerge-all-constants
1437 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1438 Attempt to merge identical constants and constant variables
1441 Common Report Var(flag_merge_constants,1) Optimization
1442 Attempt to merge identical constants across compilation units
1444 fmerge-debug-strings
1445 Common Report Var(flag_merge_debug_strings) Init(1)
1446 Attempt to merge identical debug strings across compilation units
1449 Common RejectNegative Joined UInteger
1450 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1453 Common Report Var(flag_modulo_sched) Optimization
1454 Perform SMS based modulo scheduling before the first scheduling pass
1456 fmodulo-sched-allow-regmoves
1457 Common Report Var(flag_modulo_sched_allow_regmoves)
1458 Perform SMS based modulo scheduling with register moves allowed
1460 fmove-loop-invariants
1461 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1462 Move loop invariant computations out of loops
1465 Common Var(flag_dce) Init(1) Optimization
1466 Use the RTL dead code elimination pass
1469 Common Var(flag_dse) Init(1) Optimization
1470 Use the RTL dead store elimination pass
1472 freschedule-modulo-scheduled-loops
1473 Common Report Var(flag_resched_modulo_sched) Optimization
1474 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1476 fnon-call-exceptions
1477 Common Report Var(flag_non_call_exceptions) Optimization
1478 Support synchronous non-call exceptions
1481 Common Report Var(flag_omit_frame_pointer) Optimization
1482 When possible do not generate stack frames
1484 foptimize-register-move
1485 Common Report Var(flag_regmove) Optimization
1486 Do the full register move optimization pass
1488 foptimize-sibling-calls
1489 Common Report Var(flag_optimize_sibling_calls) Optimization
1490 Optimize sibling and tail recursive calls
1493 Common Report Var(flag_partial_inlining)
1494 Perform partial inlining
1497 Common Report Var(pre_ipa_mem_report)
1498 Report on memory allocation before interprocedural optimization
1500 fpost-ipa-mem-report
1501 Common Report Var(post_ipa_mem_report)
1502 Report on memory allocation before interprocedural optimization
1505 Common Report Var(flag_pack_struct) Optimization
1506 Pack structure members together without holes
1509 Common RejectNegative Joined UInteger Optimization
1510 -fpack-struct=<number> Set initial maximum structure member alignment
1513 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1514 Return small aggregates in memory, not registers
1517 Common Report Var(flag_peel_loops) Optimization
1518 Perform loop peeling
1521 Common Report Var(flag_no_peephole,0) Optimization
1522 Enable machine specific peephole optimizations
1525 Common Report Var(flag_peephole2) Optimization
1526 Enable an RTL peephole pass before sched2
1529 Common Report Var(flag_pic,2)
1530 Generate position-independent code if possible (large mode)
1533 Common Report Var(flag_pie,2)
1534 Generate position-independent code for executables if possible (large mode)
1537 Common Report Var(flag_pic,1)
1538 Generate position-independent code if possible (small mode)
1541 Common Report Var(flag_pie,1)
1542 Generate position-independent code for executables if possible (small mode)
1545 Common Joined RejectNegative Var(common_deferred_options) Defer
1546 Specify a plugin to load
1549 Common Joined RejectNegative Var(common_deferred_options) Defer
1550 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1552 fpredictive-commoning
1553 Common Report Var(flag_predictive_commoning) Optimization
1554 Run predictive commoning optimization.
1556 fprefetch-loop-arrays
1557 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1558 Generate prefetch instructions, if available, for arrays in loops
1561 Common Report Var(profile_flag)
1562 Enable basic program profiling code
1565 Common Report Var(profile_arc_flag)
1566 Insert arc-based program profiling code
1569 Common Joined RejectNegative Var(profile_data_prefix)
1570 Set the top-level directory for storing the profile data.
1571 The default is 'pwd'.
1574 Common Report Var(flag_profile_correction)
1575 Enable correction of flow inconsistent profile data input
1579 Enable common options for generating profile info for profile feedback directed optimizations
1582 Common Joined RejectNegative
1583 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1586 Common Var(flag_profile_use)
1587 Enable common options for performing profile feedback directed optimizations
1590 Common Joined RejectNegative
1591 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1594 Common Report Var(flag_profile_values)
1595 Insert code to profile values of expressions
1598 Common Var(common_deferred_options) Defer
1601 Common Joined RejectNegative Var(common_deferred_options) Defer
1602 -frandom-seed=<string> Make compile reproducible using <string>
1604 ; This switch causes the command line that was used to create an
1605 ; object file to be recorded into the object file. The exact format
1606 ; of this recording is target and binary file format dependent.
1607 ; It is related to the -fverbose-asm switch, but that switch only
1608 ; records information in the assembler output file as comments, so
1609 ; they never reach the object file.
1610 frecord-gcc-switches
1611 Common Report Var(flag_record_gcc_switches)
1612 Record gcc command line switches in the object file.
1615 Common Report Var(flag_pcc_struct_return,0) Optimization
1616 Return small aggregates in registers
1619 Common Report Var(flag_regmove) Optimization
1620 Enables a register move optimization
1623 Common Report Var(flag_rename_registers) Init(2) Optimization
1624 Perform a register renaming optimization pass
1627 Common Report Var(flag_reorder_blocks) Optimization
1628 Reorder basic blocks to improve code placement
1630 freorder-blocks-and-partition
1631 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1632 Reorder basic blocks and partition into hot and cold sections
1635 Common Report Var(flag_reorder_functions) Optimization
1636 Reorder functions to improve code placement
1638 frerun-cse-after-loop
1639 Common Report Var(flag_rerun_cse_after_loop) Optimization
1640 Add a common subexpression elimination pass after loop optimizations
1644 Does nothing. Preserved for backward compatibility.
1647 Common Report Var(flag_rounding_math) Optimization SetByCombined
1648 Disable optimizations that assume default FP rounding behavior
1651 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1652 Enable scheduling across basic blocks
1655 Common Report Var(flag_sched_pressure) Init(0) Optimization
1656 Enable register pressure sensitive insn scheduling
1659 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1660 Allow speculative motion of non-loads
1663 Common Report Var(flag_schedule_speculative_load) Optimization
1664 Allow speculative motion of some loads
1666 fsched-spec-load-dangerous
1667 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1668 Allow speculative motion of more loads
1671 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1672 -fsched-verbose=<number> Set the verbosity level of the scheduler
1674 fsched2-use-superblocks
1675 Common Report Var(flag_sched2_use_superblocks) Optimization
1676 If scheduling post reload, do superblock scheduling
1680 Does nothing. Preserved for backward compatibility.
1683 Common Report Var(flag_schedule_insns) Optimization
1684 Reschedule instructions before register allocation
1687 Common Report Var(flag_schedule_insns_after_reload) Optimization
1688 Reschedule instructions after register allocation
1690 ; This flag should be on when a target implements non-trivial
1691 ; scheduling hooks, maybe saving some information for its own sake.
1692 ; On IA64, for example, this is used for correct bundling.
1693 fselective-scheduling
1694 Common Report Var(flag_selective_scheduling) Optimization
1695 Schedule instructions using selective scheduling algorithm
1697 fselective-scheduling2
1698 Common Report Var(flag_selective_scheduling2) Optimization
1699 Run selective scheduling after reload
1701 fsel-sched-pipelining
1702 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1703 Perform software pipelining of inner loops during selective scheduling
1705 fsel-sched-pipelining-outer-loops
1706 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1707 Perform software pipelining of outer loops during selective scheduling
1709 fsel-sched-reschedule-pipelined
1710 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1711 Reschedule pipelined regions without pipelining
1713 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1714 ; of stalled insns into the ready list.
1715 fsched-stalled-insns
1716 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1717 Allow premature scheduling of queued insns
1719 fsched-stalled-insns=
1720 Common RejectNegative Joined UInteger
1721 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1723 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1724 ; be examined for a dependency on a stalled insn that is candidate for
1725 ; premature removal from the queue of stalled insns into the ready list (has
1726 ; an effect only if the flag 'sched_stalled_insns' is set).
1727 fsched-stalled-insns-dep
1728 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1729 Set dependence distance checking in premature scheduling of queued insns
1731 fsched-stalled-insns-dep=
1732 Common RejectNegative Joined UInteger
1733 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1735 fsched-group-heuristic
1736 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1737 Enable the group heuristic in the scheduler
1739 fsched-critical-path-heuristic
1740 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1741 Enable the critical path heuristic in the scheduler
1743 fsched-spec-insn-heuristic
1744 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1745 Enable the speculative instruction heuristic in the scheduler
1747 fsched-rank-heuristic
1748 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1749 Enable the rank heuristic in the scheduler
1751 fsched-last-insn-heuristic
1752 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1753 Enable the last instruction heuristic in the scheduler
1755 fsched-dep-count-heuristic
1756 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1757 Enable the dependent count heuristic in the scheduler
1760 Common Report Var(flag_section_anchors) Optimization
1761 Access data in the same section from shared anchor points
1765 Does nothing. Preserved for backward compatibility.
1769 Does nothing. Preserved for backward compatibility.
1772 Common Report Var(flag_ree) Init(0)
1773 Turn on Redundant Extensions Elimination pass.
1776 Common Report Var(flag_show_column) Init(1)
1777 Show column numbers in diagnostics, when available. Default on
1780 Common Report Var(flag_shrink_wrap) Optimization
1781 Emit function prologues only before parts of the function that need it,
1782 rather than at the top of the function.
1785 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1786 Disable optimizations observable by IEEE signaling NaNs
1789 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1790 Disable floating point optimizations that ignore the IEEE signedness of zero
1792 fsingle-precision-constant
1793 Common Report Var(flag_single_precision_constant) Optimization
1794 Convert floating point constants to single precision constants
1796 fsplit-ivs-in-unroller
1797 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1798 Split lifetimes of induction variables when loops are unrolled
1801 Common Report Var(flag_split_stack) Init(-1)
1802 Generate discontiguous stack frames
1805 Common Report Var(flag_split_wide_types) Optimization
1806 Split wide types into independent registers
1808 fvariable-expansion-in-unroller
1809 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1810 Apply variable expansion when loops are unrolled
1813 Common Report RejectNegative Joined
1814 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1817 Common Alias(fstack-check=, specific, no)
1818 Insert stack checking code into the program. Same as -fstack-check=specific
1821 Common Var(common_deferred_options) Defer
1823 fstack-limit-register=
1824 Common RejectNegative Joined Var(common_deferred_options) Defer
1825 -fstack-limit-register=<register> Trap if the stack goes past <register>
1827 fstack-limit-symbol=
1828 Common RejectNegative Joined Var(common_deferred_options) Defer
1829 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1832 Common Report Var(flag_stack_protect, 1)
1833 Use propolice as a stack protection method
1835 fstack-protector-all
1836 Common Report RejectNegative Var(flag_stack_protect, 2)
1837 Use a stack protection method for every function
1840 Common RejectNegative Var(flag_stack_usage)
1841 Output stack usage information on a per-function basis
1845 Does nothing. Preserved for backward compatibility.
1847 ; Nonzero if we should do (language-dependent) alias analysis.
1848 ; Typically, this analysis will assume that expressions of certain
1849 ; types do not alias expressions of certain other types. Only used
1850 ; if alias analysis (in general) is enabled.
1852 Common Report Var(flag_strict_aliasing) Optimization
1853 Assume strict aliasing rules apply
1856 Common Report Var(flag_strict_overflow)
1857 Treat signed overflow as undefined
1860 Common Report Var(flag_syntax_only)
1861 Check for syntax errors, then stop
1864 Common Report Var(flag_test_coverage)
1865 Create data files needed by \"gcov\"
1868 Common Report Var(flag_thread_jumps) Optimization
1869 Perform jump threading optimizations
1872 Common Report Var(time_report)
1873 Report the time taken by each compiler pass
1876 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
1877 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
1880 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
1883 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
1886 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
1889 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
1892 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
1895 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1896 Reorder top level functions, variables, and asms
1899 Common Report Var(flag_tracer)
1900 Perform superblock formation via tail duplication
1902 ; Zero means that floating-point math operations cannot generate a
1903 ; (user-visible) trap. This is the case, for example, in nonstop
1904 ; IEEE 754 arithmetic.
1906 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
1907 Assume floating-point operations can trap
1910 Common Report Var(flag_trapv) Optimization
1911 Trap for signed overflow in addition, subtraction and multiplication
1914 Common Report Var(flag_tree_ccp) Optimization
1915 Enable SSA-CCP optimization on trees
1918 Common Report Var(flag_tree_bit_ccp) Optimization
1919 Enable SSA-BIT-CCP optimization on trees
1923 Does nothing. Preserved for backward compatibility.
1926 Common Report Var(flag_tree_ch) Optimization
1927 Enable loop header copying on trees
1930 Common Report Var(flag_tree_copyrename) Optimization
1931 Replace SSA temporaries with better names in copies
1934 Common Report Var(flag_tree_copy_prop) Optimization
1935 Enable copy propagation on trees
1937 ftree-store-copy-prop
1939 Does nothing. Preserved for backward compatibility.
1942 Common Report Var(flag_tree_cselim) Init(2) Optimization
1943 Transform condition stores into unconditional ones
1945 ftree-switch-conversion
1946 Common Report Var(flag_tree_switch_conversion) Optimization
1947 Perform conversions of switch initializations.
1950 Common Report Var(flag_tree_dce) Optimization
1951 Enable SSA dead code elimination optimization on trees
1953 ftree-dominator-opts
1954 Common Report Var(flag_tree_dom) Optimization
1955 Enable dominator optimizations
1958 Common Report Var(flag_tree_tail_merge) Optimization
1959 Enable tail merging on trees
1962 Common Report Var(flag_tree_dse) Optimization
1963 Enable dead store elimination
1966 Common Report Var(flag_tree_forwprop) Init(1) Optimization
1967 Enable forward propagation on trees
1970 Common Report Var(flag_tree_fre) Optimization
1971 Enable Full Redundancy Elimination (FRE) on trees
1974 Common Report Var(flag_optimize_strlen) Optimization
1975 Enable string length optimizations on trees
1977 ftree-loop-distribution
1978 Common Report Var(flag_tree_loop_distribution) Optimization
1979 Enable loop distribution on trees
1981 ftree-loop-distribute-patterns
1982 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
1983 Enable loop distribution for patterns transformed into a library call
1986 Common Report Var(flag_tree_loop_im) Init(1) Optimization
1987 Enable loop invariant motion on trees
1990 Common Alias(floop-interchange)
1991 Enable loop interchange transforms. Same as -floop-interchange
1994 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
1995 Create canonical induction variables in loops
1998 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
1999 Enable loop optimizations on tree level
2001 ftree-parallelize-loops=
2002 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2003 Enable automatic parallelization of loops
2006 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2007 Enable hoisting loads from conditional pointers.
2010 Common Report Var(flag_tree_pre) Optimization
2011 Enable SSA-PRE optimization on trees
2014 Common Report Var(flag_tree_pta) Init(1) Optimization
2015 Perform function-local points-to analysis on trees.
2018 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2019 Enable reassociation on tree level
2023 Does nothing. Preserved for backward compatibility.
2026 Common Report Var(flag_tree_sink) Optimization
2027 Enable SSA code sinking on trees
2030 Common Report Var(flag_tree_sra) Optimization
2031 Perform scalar replacement of aggregates
2034 Common Report Var(flag_tree_ter) Optimization
2035 Replace temporary expressions in the SSA->normal pass
2038 Common Report Var(flag_tree_live_range_split) Optimization
2039 Perform live range splitting during the SSA->normal pass
2042 Common Report Var(flag_tree_vrp) Init(0) Optimization
2043 Perform Value Range Propagation on trees
2046 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2047 Compile whole compilation unit at a time
2050 Common Report Var(flag_unroll_loops) Optimization
2051 Perform loop unrolling when iteration count is known
2054 Common Report Var(flag_unroll_all_loops) Optimization
2055 Perform loop unrolling for all loops
2057 ; Nonzero means that loop optimizer may assume that the induction variables
2058 ; that control loops do not overflow and that the loops with nontrivial
2059 ; exit condition are not infinite
2060 funsafe-loop-optimizations
2061 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2062 Allow loop optimizations to assume that the loops behave in normal way
2065 Common Report Var(flag_associative_math) SetByCombined
2066 Allow optimization for floating-point arithmetic which may change the
2067 result of the operation due to rounding.
2070 Common Report Var(flag_reciprocal_math) SetByCombined
2071 Same as -fassociative-math for expressions which include division.
2073 ; Nonzero means that unsafe floating-point math optimizations are allowed
2074 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2075 ; are allowed to assume that their arguments and results are "normal"
2076 ; (e.g., nonnegative for SQRT).
2077 funsafe-math-optimizations
2078 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2079 Allow math optimizations that may violate IEEE or ISO standards
2082 Common Report Var(flag_unswitch_loops) Optimization
2083 Perform loop unswitching
2086 Common Report Var(flag_unwind_tables) Optimization
2087 Just generate unwind tables for exception handling
2092 ; Positive if we should track variables, negative if we should run
2093 ; the var-tracking pass only to discard debug annotations, zero if
2094 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2095 ; will be set according to optimize, debug_info_level and debug_hooks
2096 ; in process_options ().
2098 Common Report Var(flag_var_tracking) Init(2) Optimization
2099 Perform variable tracking
2101 ; Positive if we should track variables at assignments, negative if
2102 ; we should run the var-tracking pass only to discard debug
2103 ; annotations. When flag_var_tracking_assignments ==
2104 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2105 fvar-tracking-assignments
2106 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2107 Perform variable tracking by annotating assignments
2109 ; Nonzero if we should toggle flag_var_tracking_assignments after
2110 ; processing options and computing its default. */
2111 fvar-tracking-assignments-toggle
2112 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2113 Toggle -fvar-tracking-assignments
2115 fvar-tracking-uninit
2116 Common Report Var(flag_var_tracking_uninit) Optimization
2117 Perform variable tracking and also tag variables that are uninitialized
2120 Common Report Var(flag_tree_vectorize) Optimization
2121 Enable loop vectorization on trees
2124 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2125 Enable basic block vectorization (SLP) on trees
2128 Common Report Var(flag_vect_cost_model) Optimization
2129 Enable use of cost model in vectorization
2131 ftree-vect-loop-version
2132 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2133 Enable loop versioning when doing loop vectorization on trees
2135 ftree-vectorizer-verbose=
2136 Common RejectNegative Joined UInteger
2137 -ftree-vectorizer-verbose=<number> Set the verbosity level of the vectorizer
2140 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2141 Enable copy propagation of scalar-evolution information.
2143 ; -fverbose-asm causes extra commentary information to be produced in
2144 ; the generated assembly code (to make it more readable). This option
2145 ; is generally only of use to those who actually need to read the
2146 ; generated assembly code (perhaps while debugging the compiler itself).
2147 ; -fno-verbose-asm, the default, causes the extra information
2148 ; to not be added and is useful when comparing two assembler files.
2150 Common Report Var(flag_verbose_asm)
2151 Add extra commentary to assembler output
2154 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2155 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2158 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2161 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2164 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2167 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2170 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2173 Common Report Var(flag_value_profile_transformations) Optimization
2174 Use expression value profiles in optimizations
2177 Common Report Var(flag_web) Init(2) Optimization
2178 Construct webs and split unrelated uses of single variable
2180 ftree-builtin-call-dce
2181 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2182 Enable conditional dead code elimination for builtin calls
2185 Common Report Var(flag_whole_program) Init(0) Optimization
2186 Perform whole program optimizations
2189 Common Report Var(flag_wrapv) Optimization
2190 Assume signed arithmetic overflow wraps around
2192 fzero-initialized-in-bss
2193 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2194 Put zero initialized data in the bss section
2197 Common JoinedOrMissing
2198 Generate debug information in default format
2201 Common JoinedOrMissing Negative(gdwarf-)
2202 Generate debug information in COFF format
2205 Common Joined UInteger Var(dwarf_version) Init(2) Negative(gstabs)
2206 Generate debug information in DWARF v2 (or later) format
2209 Common JoinedOrMissing
2210 Generate debug information in default extended format
2212 gno-record-gcc-switches
2213 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(0)
2214 Don't record gcc command line switches in DWARF DW_AT_producer.
2216 grecord-gcc-switches
2217 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2218 Record gcc command line switches in DWARF DW_AT_producer.
2221 Common JoinedOrMissing Negative(gstabs+)
2222 Generate debug information in STABS format
2225 Common JoinedOrMissing Negative(gvms)
2226 Generate debug information in extended STABS format
2229 Common RejectNegative Var(dwarf_strict,0) Init(-1)
2230 Emit DWARF additions beyond selected version
2233 Common Report RejectNegative Var(dwarf_strict,1)
2234 Don't emit DWARF additions beyond selected version
2237 Common Report Var(flag_gtoggle)
2238 Toggle debug information generation
2241 Common JoinedOrMissing Negative(gxcoff)
2242 Generate debug information in VMS format
2245 Common JoinedOrMissing Negative(gxcoff+)
2246 Generate debug information in XCOFF format
2249 Common JoinedOrMissing Negative(gcoff)
2250 Generate debug information in extended XCOFF format
2253 Driver Joined Separate
2256 Common Joined Var(plugindir_string) Init(0)
2257 -iplugindir=<dir> Set <dir> to be the default plugin directory
2260 Driver Joined Separate
2265 no-canonical-prefixes
2278 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2279 -o <file> Place output into <file>
2282 Common Var(profile_flag)
2283 Enable function profiling
2286 Driver Var(pass_exit_codes)
2289 Common Var(pedantic)
2290 Issue warnings needed for strict compliance to the standard
2293 Common Var(flag_pedantic_errors)
2294 Like -pedantic but issue them as errors
2300 Driver Var(use_pipes)
2303 Driver JoinedOrMissing Var(print_file_name)
2305 print-libgcc-file-name
2308 print-multi-directory
2309 Driver Var(print_multi_directory)
2312 Driver Var(print_multi_lib)
2314 print-multi-os-directory
2315 Driver Var(print_multi_os_directory)
2318 Driver JoinedOrMissing Var(print_prog_name)
2321 Driver Var(print_search_dirs)
2324 Driver Var(print_sysroot)
2326 print-sysroot-headers-suffix
2327 Driver Var(print_sysroot_headers_suffix)
2330 Common Var(quiet_flag) RejectDriver
2331 Do not display functions compiled or elapsed time
2349 Driver Var(report_times)
2352 Driver JoinedOrMissing
2355 Driver Joined Separate
2359 ; C option, but driver must not handle as "-u ndef".
2362 Common Driver Var(verbose_flag)
2363 Enable verbose output
2366 Common Var(version_flag) RejectDriver
2367 Display the compiler's version
2370 Common Var(inhibit_warnings)
2374 Driver Separate Var(wrapper_string)
2377 Driver Joined Separate
2380 Driver RejectNegative Negative(pie)
2381 Create a shared library
2387 Driver Separate Alias(specs=)
2400 ; Documented for Fortran, but always accepted by driver.
2407 ; Documented for Go, but always accepted by driver.
2413 Driver RejectNegative Negative(shared)
2414 Create a position independent executable
2417 Driver Joined Separate
2419 ; This comment is to ensure we retain the blank line above.