1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
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
555 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
558 Common RejectNegative Joined UInteger Warning
559 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
561 Wunsafe-loop-optimizations
562 Common Var(warn_unsafe_loop_optimizations) Warning
563 Warn if the loop cannot be optimized due to nontrivial assumptions.
566 Common Var(warn_missing_noreturn) Warning
567 Warn about functions which might be candidates for __attribute__((noreturn))
570 Common Var(warn_mudflap) Init(1) Warning
571 Warn about constructs not instrumented by -fmudflap
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.
786 ; First selectable in G++ 4.7.
788 ; Additional positive integers will be assigned as new versions of
789 ; the ABI become the default version of the ABI.
791 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
794 Common Report Var(align_functions,0) Optimization UInteger
795 Align the start of functions
798 Common RejectNegative Joined UInteger Var(align_functions)
801 Common Report Var(align_jumps,0) Optimization UInteger
802 Align labels which are only reached by jumping
805 Common RejectNegative Joined UInteger Var(align_jumps)
808 Common Report Var(align_labels,0) Optimization UInteger
812 Common RejectNegative Joined UInteger Var(align_labels)
815 Common Report Var(align_loops,0) Optimization UInteger
816 Align the start of loops
819 Common RejectNegative Joined UInteger Var(align_loops)
823 Does nothing. Preserved for backward compatibility.
827 Does nothing. Preserved for backward compatibility.
829 fargument-noalias-global
831 Does nothing. Preserved for backward compatibility.
833 fargument-noalias-anything
835 Does nothing. Preserved for backward compatibility.
837 fasynchronous-unwind-tables
838 Common Report Var(flag_asynchronous_unwind_tables) Optimization
839 Generate unwind tables that are exact at each instruction boundary
842 Common Report Var(flag_auto_inc_dec) Init(1)
843 Generate auto-inc/dec instructions
845 ; -fcheck-bounds causes gcc to generate array bounds checks.
846 ; For C, C++ and ObjC: defaults off.
847 ; For Java: defaults to on.
848 ; For Fortran: defaults to off.
850 Common Report Var(flag_bounds_check)
851 Generate code to check bounds before indexing arrays
854 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
855 Replace add, compare, branch with branch on count register
857 fbranch-probabilities
858 Common Report Var(flag_branch_probabilities) Optimization
859 Use profiling information for branch probabilities
861 fbranch-target-load-optimize
862 Common Report Var(flag_branch_target_load_optimize) Optimization
863 Perform branch target load optimization before prologue / epilogue threading
865 fbranch-target-load-optimize2
866 Common Report Var(flag_branch_target_load_optimize2) Optimization
867 Perform branch target load optimization after prologue / epilogue threading
870 Common Report Var(flag_btr_bb_exclusive) Optimization
871 Restrict target load migration not to re-use registers in any basic block
874 Common Joined RejectNegative Var(common_deferred_options) Defer
875 -fcall-saved-<register> Mark <register> as being preserved across functions
878 Common Joined RejectNegative Var(common_deferred_options) Defer
879 -fcall-used-<register> Mark <register> as being corrupted by function calls
881 ; Nonzero for -fcaller-saves: allocate values in regs that need to
882 ; be saved across function calls, if that produces overall better code.
883 ; Optional now, so people can test it.
885 Common Report Var(flag_caller_saves) Optimization
886 Save registers around function calls
889 Common Report Var(flag_check_data_deps)
890 Compare the results of several data dependence analyzers.
892 fcombine-stack-adjustments
893 Common Report Var(flag_combine_stack_adjustments) Optimization
894 Looks for opportunities to reduce stack adjustments and stack references.
897 Common Report Var(flag_no_common,0) Optimization
898 Do not put uninitialized globals in the common section
902 ; Converted by the driver to -fcompare-debug= options.
905 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
906 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
908 fcompare-debug-second
909 Common Driver RejectNegative Var(flag_compare_debug)
910 Run only the second compilation of -fcompare-debug
913 Common Report Var(flag_compare_elim_after_reload) Optimization
914 Perform comparison elimination after register allocation has finished
917 Common Var(flag_conserve_stack) Optimization
918 Do not perform optimizations increasing noticeably stack usage
921 Common Report Var(flag_cprop_registers) Optimization
922 Perform a register copy-propagation optimization pass
925 Common Report Var(flag_crossjumping) Optimization
926 Perform cross-jumping optimization
929 Common Report Var(flag_cse_follow_jumps) Optimization
930 When running CSE, follow jumps to their targets
934 Does nothing. Preserved for backward compatibility.
937 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
938 Omit range reduction step when performing complex division
941 Common Report Var(flag_cx_fortran_rules) Optimization
942 Complex multiplication and division follow Fortran rules
945 Common Report Var(flag_data_sections) Optimization
946 Place data items into their own section
949 Common Report Var(common_deferred_options) Defer
950 List all available debugging counters with their limits and counts.
953 Common RejectNegative Joined Var(common_deferred_options) Defer
954 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
957 Common Joined RejectNegative Var(common_deferred_options) Defer
958 Map one directory name to another in debug information
961 Common Report Var(flag_debug_types_section) Init(1)
962 Output .debug_types section when using DWARF v4 debuginfo.
964 ; Nonzero for -fdefer-pop: don't pop args after each function call
965 ; instead save them up to pop many calls' args with one insns.
967 Common Report Var(flag_defer_pop) Optimization
968 Defer popping functions args from stack until later
971 Common Report Var(flag_delayed_branch) Optimization
972 Attempt to fill delay slots of branch instructions
974 fdelete-null-pointer-checks
975 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
976 Delete useless null pointer checks
979 Common Report Var(flag_devirtualize) Optimization
980 Try to convert virtual calls to direct ones.
982 fdiagnostics-show-location=
983 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
984 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
986 ; Required for these enum values.
991 Name(diagnostic_prefixing_rule) Type(int)
994 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
997 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
999 fdiagnostics-show-option
1000 Common Var(flag_diagnostics_show_option) Init(1)
1001 Amend appropriate diagnostic messages with the command line option that controls them
1004 Common Joined RejectNegative Var(common_deferred_options) Defer
1005 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1008 Common Joined RejectNegative Var(common_deferred_options) Defer
1009 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1012 Common Joined RejectNegative Var(common_deferred_options) Defer
1013 -fdump-<type> Dump various compiler internals to a file
1016 Driver RejectNegative
1019 Common RejectNegative Joined Var(flag_dump_final_insns)
1020 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1023 Common RejectNegative Joined Var(flag_dump_go_spec)
1024 -fdump-go-spec=filename Write all declarations to file as Go code
1027 Common Report Var(flag_dump_noaddr)
1028 Suppress output of addresses in debugging dumps
1031 Common Var(flag_dump_passes) Init(0)
1032 Dump optimization passes
1035 Common Report Var(flag_dump_unnumbered)
1036 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1038 fdump-unnumbered-links
1039 Common Report Var(flag_dump_unnumbered_links)
1040 Suppress output of previous and next insn numbers in debugging dumps
1043 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1044 Enable CFI tables via GAS assembler directives.
1047 Common Report Var(flag_early_inlining) Init(1) Optimization
1048 Perform early inlining
1050 feliminate-dwarf2-dups
1051 Common Report Var(flag_eliminate_dwarf2_dups)
1052 Perform DWARF2 duplicate elimination
1055 Common Report Var(flag_ipa_sra) Init(0) Optimization
1056 Perform interprocedural reduction of aggregates
1058 feliminate-unused-debug-symbols
1059 Common Report Var(flag_debug_only_used_symbols)
1060 Perform unused type elimination in debug info
1062 feliminate-unused-debug-types
1063 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1064 Perform unused type elimination in debug info
1066 femit-class-debug-always
1067 Common Report Var(flag_emit_class_debug_always) Init(0)
1068 Do not suppress C++ class debug information.
1071 Common Report Var(flag_exceptions) Optimization
1072 Enable exception handling
1074 fexpensive-optimizations
1075 Common Report Var(flag_expensive_optimizations) Optimization
1076 Perform a number of minor, expensive optimizations
1079 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1080 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1083 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1086 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1089 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1095 Common Var(flag_fat_lto_objects) Init(1)
1096 Output lto objects containing both the intermediate language and binary output.
1099 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1100 Assume no NaNs or infinities are generated
1103 Common Joined RejectNegative Var(common_deferred_options) Defer
1104 -ffixed-<register> Mark <register> as being unavailable to the compiler
1107 Common Report Var(flag_float_store) Optimization
1108 Don't allocate floats and doubles in extended-precision registers
1112 Does nothing. Preserved for backward compatibility.
1115 Common Report Var(flag_forward_propagate) Optimization
1116 Perform a forward propagation pass on RTL
1119 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1120 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1123 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1126 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1128 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1130 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1133 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1135 ; Nonzero means don't put addresses of constant functions in registers.
1136 ; Used for compiling the Unix kernel, where strange substitutions are
1137 ; done on the assembly output.
1139 Common Report Var(flag_no_function_cse,0)
1140 Allow function addresses to be held in registers
1143 Common Report Var(flag_function_sections)
1144 Place each function into its own section
1147 Common Report Var(flag_gcse) Optimization
1148 Perform global common subexpression elimination
1151 Common Report Var(flag_gcse_lm) Init(1) Optimization
1152 Perform enhanced load motion during global common subexpression elimination
1155 Common Report Var(flag_gcse_sm) Init(0) Optimization
1156 Perform store motion after global common subexpression elimination
1159 Common Report Var(flag_gcse_las) Init(0) Optimization
1160 Perform redundant load after store elimination in global common subexpression
1164 Common Report Var(flag_gcse_after_reload) Optimization
1165 Perform global common subexpression elimination after register allocation
1168 ; This option is not documented yet as its semantics will change.
1170 Common Report Var(flag_graphite)
1171 Enable in and out of Graphite representation
1174 Common Report Var(flag_graphite_identity) Optimization
1175 Enable Graphite Identity transformation
1177 floop-parallelize-all
1178 Common Report Var(flag_loop_parallelize_all) Optimization
1179 Mark all loops as parallel
1182 Common Report Var(flag_loop_strip_mine) Optimization
1183 Enable Loop Strip Mining transformation
1186 Common Report Var(flag_loop_interchange) Optimization
1187 Enable Loop Interchange transformation
1190 Common Report Var(flag_loop_block) Optimization
1191 Enable Loop Blocking transformation
1194 Common Report Var(flag_loop_flatten) Optimization
1195 Enable Loop Flattening transformation
1197 fstrict-volatile-bitfields
1198 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1199 Force bitfield accesses to match their type width
1201 fguess-branch-probability
1202 Common Report Var(flag_guess_branch_prob) Optimization
1203 Enable guessing of branch probabilities
1205 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1206 ; Generate position-independent code for executables if possible
1207 ; On SVR4 targets, it also controls whether or not to emit a
1208 ; string identifying the compiler.
1210 Common Report Var(flag_no_ident,0)
1211 Process #ident directives
1214 Common Report Var(flag_if_conversion) Optimization
1215 Perform conversion of conditional jumps to branchless equivalents
1218 Common Report Var(flag_if_conversion2) Optimization
1219 Perform conversion of conditional jumps to conditional execution
1221 ftree-loop-if-convert
1222 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1223 Convert conditional jumps in innermost loops to branchless equivalents
1225 ftree-loop-if-convert-stores
1226 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1227 Also if-convert conditional jumps containing memory writes
1229 ; -finhibit-size-directive inhibits output of .size for ELF.
1230 ; This is used only for compiling crtstuff.c,
1231 ; and it may be extended to other effects
1232 ; needed for crtstuff.c on other systems.
1233 finhibit-size-directive
1234 Common Report Var(flag_inhibit_size_directive)
1235 Do not generate .size directives
1238 Common Report Var(flag_indirect_inlining)
1239 Perform indirect inlining
1241 ; Nonzero means that functions declared `inline' will be treated
1242 ; as `static'. Prevents generation of zillions of copies of unused
1243 ; static inline functions; instead, `inlines' are written out
1244 ; only when actually used. Used in conjunction with -g. Also
1245 ; does the right thing with #pragma interface.
1247 Common Report Var(flag_no_inline,0) Init(0)
1248 Pay attention to the \"inline\" keyword
1250 finline-small-functions
1251 Common Report Var(flag_inline_small_functions) Optimization
1252 Integrate simple functions into their callers when code size is known to not growth
1255 Common Report Var(flag_inline_functions) Optimization
1256 Integrate simple functions into their callers
1258 finline-functions-called-once
1259 Common Report Var(flag_inline_functions_called_once) Optimization
1260 Integrate functions called once into their callers
1263 Common RejectNegative Joined Alias(finline-limit=)
1266 Common RejectNegative Joined UInteger
1267 -finline-limit=<number> Limit the size of inlined functions to <number>
1269 finstrument-functions
1270 Common Report Var(flag_instrument_function_entry_exit)
1271 Instrument function entry and exit with profiling calls
1273 finstrument-functions-exclude-function-list=
1274 Common RejectNegative Joined
1275 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1277 finstrument-functions-exclude-file-list=
1278 Common RejectNegative Joined
1279 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1282 Common Report Var(flag_ipa_cp) Optimization
1283 Perform Interprocedural constant propagation
1286 Common Report Var(flag_ipa_cp_clone) Optimization
1287 Perform cloning to make Interprocedural constant propagation stronger
1290 Common Report Var(flag_ipa_profile) Init(0) Optimization
1291 Perform interprocedural profile propagation
1294 Common Report Var(flag_ipa_pta) Init(0) Optimization
1295 Perform interprocedural points-to analysis
1298 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1299 Discover pure and const functions
1302 Common Report Var(flag_ipa_reference) Init(0) Optimization
1303 Discover readonly and non addressable static variables
1306 Common Report Var(flag_ipa_matrix_reorg) Optimization
1307 Perform matrix layout flattening and transposing based
1308 on profiling information.
1312 Does nothing. Preserved for backward compatibility.
1315 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1316 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1319 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1322 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1325 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1328 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_MIXED)
1329 -fira-region=[one|all|mixed] Set regions for IRA
1332 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1335 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1338 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1341 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1344 Common Report Var(flag_ira_loop_pressure)
1345 Use IRA based register pressure calculation
1346 in RTL loop optimizations.
1348 fira-share-save-slots
1349 Common Report Var(flag_ira_share_save_slots) Init(1)
1350 Share slots for saving different hard registers.
1352 fira-share-spill-slots
1353 Common Report Var(flag_ira_share_spill_slots) Init(1)
1354 Share stack slots for spilled pseudo-registers.
1357 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1358 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1361 Common Report Var(flag_ivopts) Init(1) Optimization
1362 Optimize induction variables on trees
1365 Common Var(flag_jump_tables) Init(1) Optimization
1366 Use jump tables for sufficiently large switch statements
1368 fkeep-inline-functions
1369 Common Report Var(flag_keep_inline_functions)
1370 Generate code for functions even if they are fully inlined
1373 Common Report Var(flag_keep_static_consts) Init(1)
1374 Emit static const variables even if they are not used
1377 Common Report Var(flag_leading_underscore) Init(-1)
1378 Give external symbols a leading underscore
1382 Does nothing. Preserved for backward compatibility.
1386 Enable link-time optimization.
1389 Common RejectNegative Joined Var(flag_lto)
1390 Link-time optimization with number of parallel jobs or jobserver.
1393 Common Var(flag_lto_partition_1to1)
1394 Partition functions and vars at linktime based on object files they originate from
1396 flto-partition=balanced
1397 Common Var(flag_lto_partition_balanced)
1398 Partition functions and vars at linktime into approximately same sized buckets
1401 Common Var(flag_lto_partition_none)
1402 Disable partioning and streaming
1404 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1405 flto-compression-level=
1406 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1407 -flto-compression-level=<number> Use zlib compression level <number> for IL
1410 Common Report Var(flag_lto_report) Init(0) Optimization
1411 Report various link-time optimization statistics
1414 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1415 Set errno after built-in math functions
1418 Common Joined RejectNegative UInteger Var(flag_max_errors)
1419 -fmax-errors=<number> Maximum number of errors to report
1422 Common Report Var(mem_report)
1423 Report on permanent memory allocation
1425 ; This will attempt to merge constant section constants, if 1 only
1426 ; string constants and constants from constant pool, if 2 also constant
1428 fmerge-all-constants
1429 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1430 Attempt to merge identical constants and constant variables
1433 Common Report Var(flag_merge_constants,1) Optimization
1434 Attempt to merge identical constants across compilation units
1436 fmerge-debug-strings
1437 Common Report Var(flag_merge_debug_strings) Init(1)
1438 Attempt to merge identical debug strings across compilation units
1441 Common RejectNegative Joined UInteger
1442 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1445 Common Report Var(flag_modulo_sched) Optimization
1446 Perform SMS based modulo scheduling before the first scheduling pass
1448 fmodulo-sched-allow-regmoves
1449 Common Report Var(flag_modulo_sched_allow_regmoves)
1450 Perform SMS based modulo scheduling with register moves allowed
1452 fmove-loop-invariants
1453 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1454 Move loop invariant computations out of loops
1457 Common RejectNegative Report Var(flag_mudflap)
1458 Add mudflap bounds-checking instrumentation for single-threaded program
1461 Common RejectNegative Report Var(flag_mudflap,2)
1462 Add mudflap bounds-checking instrumentation for multi-threaded program
1465 Common RejectNegative Report Var(flag_mudflap_ignore_reads)
1466 Ignore read operations when inserting mudflap instrumentation
1469 Common Var(flag_dce) Init(1) Optimization
1470 Use the RTL dead code elimination pass
1473 Common Var(flag_dse) Init(1) Optimization
1474 Use the RTL dead store elimination pass
1476 freschedule-modulo-scheduled-loops
1477 Common Report Var(flag_resched_modulo_sched) Optimization
1478 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1480 fnon-call-exceptions
1481 Common Report Var(flag_non_call_exceptions) Optimization
1482 Support synchronous non-call exceptions
1485 Common Report Var(flag_omit_frame_pointer) Optimization
1486 When possible do not generate stack frames
1488 foptimize-register-move
1489 Common Report Var(flag_regmove) Optimization
1490 Do the full register move optimization pass
1492 foptimize-sibling-calls
1493 Common Report Var(flag_optimize_sibling_calls) Optimization
1494 Optimize sibling and tail recursive calls
1497 Common Report Var(flag_partial_inlining)
1498 Perform partial inlining
1501 Common Report Var(pre_ipa_mem_report)
1502 Report on memory allocation before interprocedural optimization
1504 fpost-ipa-mem-report
1505 Common Report Var(post_ipa_mem_report)
1506 Report on memory allocation before interprocedural optimization
1509 Common Report Var(flag_pack_struct) Optimization
1510 Pack structure members together without holes
1513 Common RejectNegative Joined UInteger Optimization
1514 -fpack-struct=<number> Set initial maximum structure member alignment
1517 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1518 Return small aggregates in memory, not registers
1521 Common Report Var(flag_peel_loops) Optimization
1522 Perform loop peeling
1525 Common Report Var(flag_no_peephole,0) Optimization
1526 Enable machine specific peephole optimizations
1529 Common Report Var(flag_peephole2) Optimization
1530 Enable an RTL peephole pass before sched2
1533 Common Report Var(flag_pic,2)
1534 Generate position-independent code if possible (large mode)
1537 Common Report Var(flag_pie,2)
1538 Generate position-independent code for executables if possible (large mode)
1541 Common Report Var(flag_pic,1)
1542 Generate position-independent code if possible (small mode)
1545 Common Report Var(flag_pie,1)
1546 Generate position-independent code for executables if possible (small mode)
1549 Common Joined RejectNegative Var(common_deferred_options) Defer
1550 Specify a plugin to load
1553 Common Joined RejectNegative Var(common_deferred_options) Defer
1554 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1556 fpredictive-commoning
1557 Common Report Var(flag_predictive_commoning) Optimization
1558 Run predictive commoning optimization.
1560 fprefetch-loop-arrays
1561 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1562 Generate prefetch instructions, if available, for arrays in loops
1565 Common Report Var(profile_flag)
1566 Enable basic program profiling code
1569 Common Report Var(profile_arc_flag)
1570 Insert arc-based program profiling code
1573 Common Joined RejectNegative Var(profile_data_prefix)
1574 Set the top-level directory for storing the profile data.
1575 The default is 'pwd'.
1578 Common Report Var(flag_profile_correction)
1579 Enable correction of flow inconsistent profile data input
1583 Enable common options for generating profile info for profile feedback directed optimizations
1586 Common Joined RejectNegative
1587 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1590 Common Var(flag_profile_use)
1591 Enable common options for performing profile feedback directed optimizations
1594 Common Joined RejectNegative
1595 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1598 Common Report Var(flag_profile_values)
1599 Insert code to profile values of expressions
1602 Common Var(common_deferred_options) Defer
1605 Common Joined RejectNegative Var(common_deferred_options) Defer
1606 -frandom-seed=<string> Make compile reproducible using <string>
1608 ; This switch causes the command line that was used to create an
1609 ; object file to be recorded into the object file. The exact format
1610 ; of this recording is target and binary file format dependent.
1611 ; It is related to the -fverbose-asm switch, but that switch only
1612 ; records information in the assembler output file as comments, so
1613 ; they never reach the object file.
1614 frecord-gcc-switches
1615 Common Report Var(flag_record_gcc_switches)
1616 Record gcc command line switches in the object file.
1619 Common Report Var(flag_pcc_struct_return,0) Optimization
1620 Return small aggregates in registers
1623 Common Report Var(flag_regmove) Optimization
1624 Enables a register move optimization
1627 Common Report Var(flag_rename_registers) Init(2) Optimization
1628 Perform a register renaming optimization pass
1631 Common Report Var(flag_reorder_blocks) Optimization
1632 Reorder basic blocks to improve code placement
1634 freorder-blocks-and-partition
1635 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1636 Reorder basic blocks and partition into hot and cold sections
1639 Common Report Var(flag_reorder_functions) Optimization
1640 Reorder functions to improve code placement
1642 frerun-cse-after-loop
1643 Common Report Var(flag_rerun_cse_after_loop) Optimization
1644 Add a common subexpression elimination pass after loop optimizations
1648 Does nothing. Preserved for backward compatibility.
1651 Common Report Var(flag_rounding_math) Optimization SetByCombined
1652 Disable optimizations that assume default FP rounding behavior
1655 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1656 Enable scheduling across basic blocks
1659 Common Report Var(flag_sched_pressure) Init(0) Optimization
1660 Enable register pressure sensitive insn scheduling
1663 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1664 Allow speculative motion of non-loads
1667 Common Report Var(flag_schedule_speculative_load) Optimization
1668 Allow speculative motion of some loads
1670 fsched-spec-load-dangerous
1671 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1672 Allow speculative motion of more loads
1675 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1676 -fsched-verbose=<number> Set the verbosity level of the scheduler
1678 fsched2-use-superblocks
1679 Common Report Var(flag_sched2_use_superblocks) Optimization
1680 If scheduling post reload, do superblock scheduling
1684 Does nothing. Preserved for backward compatibility.
1687 Common Report Var(flag_schedule_insns) Optimization
1688 Reschedule instructions before register allocation
1691 Common Report Var(flag_schedule_insns_after_reload) Optimization
1692 Reschedule instructions after register allocation
1694 ; This flag should be on when a target implements non-trivial
1695 ; scheduling hooks, maybe saving some information for its own sake.
1696 ; On IA64, for example, this is used for correct bundling.
1697 fselective-scheduling
1698 Common Report Var(flag_selective_scheduling) Optimization
1699 Schedule instructions using selective scheduling algorithm
1701 fselective-scheduling2
1702 Common Report Var(flag_selective_scheduling2) Optimization
1703 Run selective scheduling after reload
1705 fsel-sched-pipelining
1706 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1707 Perform software pipelining of inner loops during selective scheduling
1709 fsel-sched-pipelining-outer-loops
1710 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1711 Perform software pipelining of outer loops during selective scheduling
1713 fsel-sched-reschedule-pipelined
1714 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1715 Reschedule pipelined regions without pipelining
1717 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1718 ; of stalled insns into the ready list.
1719 fsched-stalled-insns
1720 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1721 Allow premature scheduling of queued insns
1723 fsched-stalled-insns=
1724 Common RejectNegative Joined UInteger
1725 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1727 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1728 ; be examined for a dependency on a stalled insn that is candidate for
1729 ; premature removal from the queue of stalled insns into the ready list (has
1730 ; an effect only if the flag 'sched_stalled_insns' is set).
1731 fsched-stalled-insns-dep
1732 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1733 Set dependence distance checking in premature scheduling of queued insns
1735 fsched-stalled-insns-dep=
1736 Common RejectNegative Joined UInteger
1737 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1739 fsched-group-heuristic
1740 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1741 Enable the group heuristic in the scheduler
1743 fsched-critical-path-heuristic
1744 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1745 Enable the critical path heuristic in the scheduler
1747 fsched-spec-insn-heuristic
1748 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1749 Enable the speculative instruction heuristic in the scheduler
1751 fsched-rank-heuristic
1752 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1753 Enable the rank heuristic in the scheduler
1755 fsched-last-insn-heuristic
1756 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1757 Enable the last instruction heuristic in the scheduler
1759 fsched-dep-count-heuristic
1760 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1761 Enable the dependent count heuristic in the scheduler
1764 Common Report Var(flag_section_anchors) Optimization
1765 Access data in the same section from shared anchor points
1769 Does nothing. Preserved for backward compatibility.
1772 Common Report Var(flag_zee) Init(0)
1773 Eliminate redundant zero extensions on targets that support implicit extensions.
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 Common 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 Common 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.