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
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_mudflap) Init(1) Warning
575 Warn about constructs not instrumented by -fmudflap
578 Common Var(warn_overflow) Init(1) Warning
579 Warn about overflow in arithmetic expressions
582 Common Var(warn_packed) Warning
583 Warn when the packed attribute has no effect on struct layout
586 Common Var(warn_padded) Warning
587 Warn when padding is required to align structure members
590 Common Var(warn_shadow) Warning
591 Warn when one local variable shadows another
594 Common Var(warn_stack_protect) Warning
595 Warn when not issuing stack smashing protection for some reason
598 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
599 Warn if stack usage might be larger than specified amount
603 Warn about code which might break strict aliasing rules
606 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Init(-1) Warning
607 Warn about code which might break strict aliasing rules
611 Warn about optimizations that assume that signed overflow is undefined
614 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Init(-1) Warning
615 Warn about optimizations that assume that signed overflow is undefined
617 Wsuggest-attribute=const
618 Common Var(warn_suggest_attribute_const) Warning
619 Warn about functions which might be candidates for __attribute__((const))
621 Wsuggest-attribute=pure
622 Common Var(warn_suggest_attribute_pure) Warning
623 Warn about functions which might be candidates for __attribute__((pure))
625 Wsuggest-attribute=noreturn
626 Common Var(warn_suggest_attribute_noreturn) Warning
627 Warn about functions which might be candidates for __attribute__((noreturn))
630 Common Var(warn_switch) Warning
631 Warn about enumerated switches, with no default, missing a case
634 Common Var(warn_switch_default) Warning
635 Warn about enumerated switches missing a \"default:\" statement
638 Common Var(warn_switch_enum) Warning
639 Warn about all enumerated switches missing a specific case
642 Common Var(warn_system_headers) Warning
643 Do not suppress warnings from system headers
646 Common Var(warn_trampolines) Warning
647 Warn whenever a trampoline is generated
650 Common Var(warn_type_limits) Init(-1) Warning
651 Warn if a comparison is always true or always false due to the limited range of the data type
654 Common Var(warn_uninitialized) Init(-1) Warning
655 Warn about uninitialized automatic variables
658 Common Var(warn_maybe_uninitialized) Warning
659 Warn about maybe uninitialized automatic variables
663 Does nothing. Preserved for backward compatibility.
666 Common Var(warn_unused) Init(0) Warning
667 Enable all -Wunused- warnings
669 Wunused-but-set-parameter
670 Common Var(warn_unused_but_set_parameter) Init(-1) Warning
671 Warn when a function parameter is only set, otherwise unused
673 Wunused-but-set-variable
674 Common Var(warn_unused_but_set_variable) Init(-1) Warning
675 Warn when a variable is only set, otherwise unused
678 Common Var(warn_unused_function) Init(-1) Warning
679 Warn when a function is unused
682 Common Var(warn_unused_label) Init(-1) Warning
683 Warn when a label is unused
686 Common Var(warn_unused_parameter) Init(-1) Warning
687 Warn when a function parameter is unused
690 Common Var(warn_unused_value) Init(-1) Warning
691 Warn when an expression value is unused
694 Common Var(warn_unused_variable) Init(-1) Warning
695 Warn when a variable is unused
698 Common Var(warn_coverage_mismatch) Init(1) Warning
699 Warn in case profiles in -fprofile-use do not match
701 Wvector-operation-performance
702 Common Var(warn_vector_operation_performance) Warning
703 Warn when a vector operation is compiled outside the SIMD
718 Common Separate Var(aux_info_file_name)
719 -aux-info <file> Emit declaration information into <file>
722 Common Joined Alias(aux-info)
725 Common Separate RejectDriver Var(aux_base_name)
728 Common Separate RejectDriver
738 -d<letters> Enable dumps from specific passes of the compiler
741 Common Separate Var(dump_base_name)
742 -dumpbase <file> Set the file basename to be used for dumps
745 Common Separate Var(dump_dir_name)
746 -dumpdir <dir> Set the directory name to be used for dumps
758 Driver Joined Separate
760 ; This option has historically been passed down to the linker by an
761 ; accident of a %{e*} spec, so ensure it continues to be passed down
762 ; as a single option. The supported option for this purpose is
763 ; -rdynamic. See PR 47390.
767 ; The version of the C++ ABI in use. The following values are allowed:
769 ; 0: The version of the ABI believed most conformant with the C++ ABI
770 ; specification. This ABI may change as bugs are discovered and fixed.
771 ; Therefore, 0 will not necessarily indicate the same ABI in different
774 ; 1: The version of the ABI first used in G++ 3.2.
776 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
778 ; 3: The version of the ABI that fixes the missing underscore
779 ; in template non-type arguments of pointer type.
781 ; 4: The version of the ABI that introduces unambiguous mangling of
782 ; vector types. First selectable in G++ 4.5.
784 ; 5: The version of the ABI that ignores attribute const/noreturn
785 ; in function pointer mangling, and corrects mangling of decltype and
786 ; function parameters used in other parameters and the return type.
787 ; First selectable in G++ 4.6.
789 ; 6: The version of the ABI that doesn't promote scoped enums to int.
790 ; First selectable in G++ 4.7.
792 ; Additional positive integers will be assigned as new versions of
793 ; the ABI become the default version of the ABI.
795 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
798 Common Report Var(align_functions,0) Optimization UInteger
799 Align the start of functions
802 Common RejectNegative Joined UInteger Var(align_functions)
805 Common Report Var(align_jumps,0) Optimization UInteger
806 Align labels which are only reached by jumping
809 Common RejectNegative Joined UInteger Var(align_jumps)
812 Common Report Var(align_labels,0) Optimization UInteger
816 Common RejectNegative Joined UInteger Var(align_labels)
819 Common Report Var(align_loops,0) Optimization UInteger
820 Align the start of loops
823 Common RejectNegative Joined UInteger Var(align_loops)
827 Does nothing. Preserved for backward compatibility.
831 Does nothing. Preserved for backward compatibility.
833 fargument-noalias-global
835 Does nothing. Preserved for backward compatibility.
837 fargument-noalias-anything
839 Does nothing. Preserved for backward compatibility.
841 fasynchronous-unwind-tables
842 Common Report Var(flag_asynchronous_unwind_tables) Optimization
843 Generate unwind tables that are exact at each instruction boundary
846 Common Report Var(flag_auto_inc_dec) Init(1)
847 Generate auto-inc/dec instructions
849 ; -fcheck-bounds causes gcc to generate array bounds checks.
850 ; For C, C++ and ObjC: defaults off.
851 ; For Java: defaults to on.
852 ; For Fortran: defaults to off.
854 Common Report Var(flag_bounds_check)
855 Generate code to check bounds before indexing arrays
858 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
859 Replace add, compare, branch with branch on count register
861 fbranch-probabilities
862 Common Report Var(flag_branch_probabilities) Optimization
863 Use profiling information for branch probabilities
865 fbranch-target-load-optimize
866 Common Report Var(flag_branch_target_load_optimize) Optimization
867 Perform branch target load optimization before prologue / epilogue threading
869 fbranch-target-load-optimize2
870 Common Report Var(flag_branch_target_load_optimize2) Optimization
871 Perform branch target load optimization after prologue / epilogue threading
874 Common Report Var(flag_btr_bb_exclusive) Optimization
875 Restrict target load migration not to re-use registers in any basic block
878 Common Joined RejectNegative Var(common_deferred_options) Defer
879 -fcall-saved-<register> Mark <register> as being preserved across functions
882 Common Joined RejectNegative Var(common_deferred_options) Defer
883 -fcall-used-<register> Mark <register> as being corrupted by function calls
885 ; Nonzero for -fcaller-saves: allocate values in regs that need to
886 ; be saved across function calls, if that produces overall better code.
887 ; Optional now, so people can test it.
889 Common Report Var(flag_caller_saves) Optimization
890 Save registers around function calls
893 Common Report Var(flag_check_data_deps)
894 Compare the results of several data dependence analyzers.
896 fcombine-stack-adjustments
897 Common Report Var(flag_combine_stack_adjustments) Optimization
898 Looks for opportunities to reduce stack adjustments and stack references.
901 Common Report Var(flag_no_common,0) Optimization
902 Do not put uninitialized globals in the common section
906 ; Converted by the driver to -fcompare-debug= options.
909 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
910 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
912 fcompare-debug-second
913 Common Driver RejectNegative Var(flag_compare_debug)
914 Run only the second compilation of -fcompare-debug
917 Common Report Var(flag_compare_elim_after_reload) Optimization
918 Perform comparison elimination after register allocation has finished
921 Common Var(flag_conserve_stack) Optimization
922 Do not perform optimizations increasing noticeably stack usage
925 Common Report Var(flag_cprop_registers) Optimization
926 Perform a register copy-propagation optimization pass
929 Common Report Var(flag_crossjumping) Optimization
930 Perform cross-jumping optimization
933 Common Report Var(flag_cse_follow_jumps) Optimization
934 When running CSE, follow jumps to their targets
938 Does nothing. Preserved for backward compatibility.
941 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
942 Omit range reduction step when performing complex division
945 Common Report Var(flag_cx_fortran_rules) Optimization
946 Complex multiplication and division follow Fortran rules
949 Common Report Var(flag_data_sections) Optimization
950 Place data items into their own section
953 Common Report Var(common_deferred_options) Defer
954 List all available debugging counters with their limits and counts.
957 Common RejectNegative Joined Var(common_deferred_options) Defer
958 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
961 Common Joined RejectNegative Var(common_deferred_options) Defer
962 Map one directory name to another in debug information
965 Common Report Var(flag_debug_types_section) Init(1)
966 Output .debug_types section when using DWARF v4 debuginfo.
968 ; Nonzero for -fdefer-pop: don't pop args after each function call
969 ; instead save them up to pop many calls' args with one insns.
971 Common Report Var(flag_defer_pop) Optimization
972 Defer popping functions args from stack until later
975 Common Report Var(flag_delayed_branch) Optimization
976 Attempt to fill delay slots of branch instructions
978 fdelete-null-pointer-checks
979 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
980 Delete useless null pointer checks
983 Common Report Var(flag_devirtualize) Optimization
984 Try to convert virtual calls to direct ones.
986 fdiagnostics-show-location=
987 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
988 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
990 ; Required for these enum values.
995 Name(diagnostic_prefixing_rule) Type(int)
998 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1001 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1003 fdiagnostics-show-option
1004 Common Var(flag_diagnostics_show_option) Init(1)
1005 Amend appropriate diagnostic messages with the command line option that controls them
1008 Common Joined RejectNegative Var(common_deferred_options) Defer
1009 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1012 Common Joined RejectNegative Var(common_deferred_options) Defer
1013 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1016 Common Joined RejectNegative Var(common_deferred_options) Defer
1017 -fdump-<type> Dump various compiler internals to a file
1020 Driver RejectNegative
1023 Common RejectNegative Joined Var(flag_dump_final_insns)
1024 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1027 Common RejectNegative Joined Var(flag_dump_go_spec)
1028 -fdump-go-spec=filename Write all declarations to file as Go code
1031 Common Report Var(flag_dump_noaddr)
1032 Suppress output of addresses in debugging dumps
1035 Common Var(flag_dump_passes) Init(0)
1036 Dump optimization passes
1039 Common Report Var(flag_dump_unnumbered)
1040 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1042 fdump-unnumbered-links
1043 Common Report Var(flag_dump_unnumbered_links)
1044 Suppress output of previous and next insn numbers in debugging dumps
1047 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1048 Enable CFI tables via GAS assembler directives.
1051 Common Report Var(flag_early_inlining) Init(1) Optimization
1052 Perform early inlining
1054 feliminate-dwarf2-dups
1055 Common Report Var(flag_eliminate_dwarf2_dups)
1056 Perform DWARF2 duplicate elimination
1059 Common Report Var(flag_ipa_sra) Init(0) Optimization
1060 Perform interprocedural reduction of aggregates
1062 feliminate-unused-debug-symbols
1063 Common Report Var(flag_debug_only_used_symbols)
1064 Perform unused type elimination in debug info
1066 feliminate-unused-debug-types
1067 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1068 Perform unused type elimination in debug info
1070 femit-class-debug-always
1071 Common Report Var(flag_emit_class_debug_always) Init(0)
1072 Do not suppress C++ class debug information.
1075 Common Report Var(flag_exceptions) Optimization
1076 Enable exception handling
1078 fexpensive-optimizations
1079 Common Report Var(flag_expensive_optimizations) Optimization
1080 Perform a number of minor, expensive optimizations
1083 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1084 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1087 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1090 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1093 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1099 Common Var(flag_fat_lto_objects) Init(1)
1100 Output lto objects containing both the intermediate language and binary output.
1103 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1104 Assume no NaNs or infinities are generated
1107 Common Joined RejectNegative Var(common_deferred_options) Defer
1108 -ffixed-<register> Mark <register> as being unavailable to the compiler
1111 Common Report Var(flag_float_store) Optimization
1112 Don't allocate floats and doubles in extended-precision registers
1116 Does nothing. Preserved for backward compatibility.
1119 Common Report Var(flag_forward_propagate) Optimization
1120 Perform a forward propagation pass on RTL
1123 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1124 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1127 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1130 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1132 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1134 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1137 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1139 ; Nonzero means don't put addresses of constant functions in registers.
1140 ; Used for compiling the Unix kernel, where strange substitutions are
1141 ; done on the assembly output.
1143 Common Report Var(flag_no_function_cse,0)
1144 Allow function addresses to be held in registers
1147 Common Report Var(flag_function_sections)
1148 Place each function into its own section
1151 Common Report Var(flag_gcse) Optimization
1152 Perform global common subexpression elimination
1155 Common Report Var(flag_gcse_lm) Init(1) Optimization
1156 Perform enhanced load motion during global common subexpression elimination
1159 Common Report Var(flag_gcse_sm) Init(0) Optimization
1160 Perform store motion after global common subexpression elimination
1163 Common Report Var(flag_gcse_las) Init(0) Optimization
1164 Perform redundant load after store elimination in global common subexpression
1168 Common Report Var(flag_gcse_after_reload) Optimization
1169 Perform global common subexpression elimination after register allocation
1172 ; This option is not documented yet as its semantics will change.
1174 Common Report Var(flag_graphite)
1175 Enable in and out of Graphite representation
1178 Common Report Var(flag_graphite_identity) Optimization
1179 Enable Graphite Identity transformation
1181 floop-parallelize-all
1182 Common Report Var(flag_loop_parallelize_all) Optimization
1183 Mark all loops as parallel
1186 Common Report Var(flag_loop_strip_mine) Optimization
1187 Enable Loop Strip Mining transformation
1190 Common Report Var(flag_loop_interchange) Optimization
1191 Enable Loop Interchange transformation
1194 Common Report Var(flag_loop_block) Optimization
1195 Enable Loop Blocking transformation
1198 Common Report Var(flag_loop_flatten) Optimization
1199 Enable Loop Flattening transformation
1201 fstrict-volatile-bitfields
1202 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1203 Force bitfield accesses to match their type width
1205 fguess-branch-probability
1206 Common Report Var(flag_guess_branch_prob) Optimization
1207 Enable guessing of branch probabilities
1209 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1210 ; Generate position-independent code for executables if possible
1211 ; On SVR4 targets, it also controls whether or not to emit a
1212 ; string identifying the compiler.
1214 Common Report Var(flag_no_ident,0)
1215 Process #ident directives
1218 Common Report Var(flag_if_conversion) Optimization
1219 Perform conversion of conditional jumps to branchless equivalents
1222 Common Report Var(flag_if_conversion2) Optimization
1223 Perform conversion of conditional jumps to conditional execution
1225 ftree-loop-if-convert
1226 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1227 Convert conditional jumps in innermost loops to branchless equivalents
1229 ftree-loop-if-convert-stores
1230 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1231 Also if-convert conditional jumps containing memory writes
1233 ; -finhibit-size-directive inhibits output of .size for ELF.
1234 ; This is used only for compiling crtstuff.c,
1235 ; and it may be extended to other effects
1236 ; needed for crtstuff.c on other systems.
1237 finhibit-size-directive
1238 Common Report Var(flag_inhibit_size_directive)
1239 Do not generate .size directives
1242 Common Report Var(flag_indirect_inlining)
1243 Perform indirect inlining
1245 ; Nonzero means that functions declared `inline' will be treated
1246 ; as `static'. Prevents generation of zillions of copies of unused
1247 ; static inline functions; instead, `inlines' are written out
1248 ; only when actually used. Used in conjunction with -g. Also
1249 ; does the right thing with #pragma interface.
1251 Common Report Var(flag_no_inline,0) Init(0)
1252 Pay attention to the \"inline\" keyword
1254 finline-small-functions
1255 Common Report Var(flag_inline_small_functions) Optimization
1256 Integrate simple functions into their callers when code size is known to not growth
1259 Common Report Var(flag_inline_functions) Optimization
1260 Integrate simple functions into their callers
1262 finline-functions-called-once
1263 Common Report Var(flag_inline_functions_called_once) Optimization
1264 Integrate functions called once into their callers
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_MIXED)
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) Optimization
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 RejectNegative Report Var(flag_mudflap)
1466 Add mudflap bounds-checking instrumentation for single-threaded program
1469 Common RejectNegative Report Var(flag_mudflap,2)
1470 Add mudflap bounds-checking instrumentation for multi-threaded program
1473 Common RejectNegative Report Var(flag_mudflap_ignore_reads)
1474 Ignore read operations when inserting mudflap instrumentation
1477 Common Var(flag_dce) Init(1) Optimization
1478 Use the RTL dead code elimination pass
1481 Common Var(flag_dse) Init(1) Optimization
1482 Use the RTL dead store elimination pass
1484 freschedule-modulo-scheduled-loops
1485 Common Report Var(flag_resched_modulo_sched) Optimization
1486 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1488 fnon-call-exceptions
1489 Common Report Var(flag_non_call_exceptions) Optimization
1490 Support synchronous non-call exceptions
1493 Common Report Var(flag_omit_frame_pointer) Optimization
1494 When possible do not generate stack frames
1496 foptimize-register-move
1497 Common Report Var(flag_regmove) Optimization
1498 Do the full register move optimization pass
1500 foptimize-sibling-calls
1501 Common Report Var(flag_optimize_sibling_calls) Optimization
1502 Optimize sibling and tail recursive calls
1505 Common Report Var(flag_partial_inlining)
1506 Perform partial inlining
1509 Common Report Var(pre_ipa_mem_report)
1510 Report on memory allocation before interprocedural optimization
1512 fpost-ipa-mem-report
1513 Common Report Var(post_ipa_mem_report)
1514 Report on memory allocation before interprocedural optimization
1517 Common Report Var(flag_pack_struct) Optimization
1518 Pack structure members together without holes
1521 Common RejectNegative Joined UInteger Optimization
1522 -fpack-struct=<number> Set initial maximum structure member alignment
1525 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1526 Return small aggregates in memory, not registers
1529 Common Report Var(flag_peel_loops) Optimization
1530 Perform loop peeling
1533 Common Report Var(flag_no_peephole,0) Optimization
1534 Enable machine specific peephole optimizations
1537 Common Report Var(flag_peephole2) Optimization
1538 Enable an RTL peephole pass before sched2
1541 Common Report Var(flag_pic,2)
1542 Generate position-independent code if possible (large mode)
1545 Common Report Var(flag_pie,2)
1546 Generate position-independent code for executables if possible (large mode)
1549 Common Report Var(flag_pic,1)
1550 Generate position-independent code if possible (small mode)
1553 Common Report Var(flag_pie,1)
1554 Generate position-independent code for executables if possible (small mode)
1557 Common Joined RejectNegative Var(common_deferred_options) Defer
1558 Specify a plugin to load
1561 Common Joined RejectNegative Var(common_deferred_options) Defer
1562 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1564 fpredictive-commoning
1565 Common Report Var(flag_predictive_commoning) Optimization
1566 Run predictive commoning optimization.
1568 fprefetch-loop-arrays
1569 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1570 Generate prefetch instructions, if available, for arrays in loops
1573 Common Report Var(profile_flag)
1574 Enable basic program profiling code
1577 Common Report Var(profile_arc_flag)
1578 Insert arc-based program profiling code
1581 Common Joined RejectNegative Var(profile_data_prefix)
1582 Set the top-level directory for storing the profile data.
1583 The default is 'pwd'.
1586 Common Report Var(flag_profile_correction)
1587 Enable correction of flow inconsistent profile data input
1591 Enable common options for generating profile info for profile feedback directed optimizations
1594 Common Joined RejectNegative
1595 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1598 Common Var(flag_profile_use)
1599 Enable common options for performing profile feedback directed optimizations
1602 Common Joined RejectNegative
1603 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1606 Common Report Var(flag_profile_values)
1607 Insert code to profile values of expressions
1610 Common Var(common_deferred_options) Defer
1613 Common Joined RejectNegative Var(common_deferred_options) Defer
1614 -frandom-seed=<string> Make compile reproducible using <string>
1616 ; This switch causes the command line that was used to create an
1617 ; object file to be recorded into the object file. The exact format
1618 ; of this recording is target and binary file format dependent.
1619 ; It is related to the -fverbose-asm switch, but that switch only
1620 ; records information in the assembler output file as comments, so
1621 ; they never reach the object file.
1622 frecord-gcc-switches
1623 Common Report Var(flag_record_gcc_switches)
1624 Record gcc command line switches in the object file.
1627 Common Report Var(flag_pcc_struct_return,0) Optimization
1628 Return small aggregates in registers
1631 Common Report Var(flag_regmove) Optimization
1632 Enables a register move optimization
1635 Common Report Var(flag_rename_registers) Init(2) Optimization
1636 Perform a register renaming optimization pass
1639 Common Report Var(flag_reorder_blocks) Optimization
1640 Reorder basic blocks to improve code placement
1642 freorder-blocks-and-partition
1643 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1644 Reorder basic blocks and partition into hot and cold sections
1647 Common Report Var(flag_reorder_functions) Optimization
1648 Reorder functions to improve code placement
1650 frerun-cse-after-loop
1651 Common Report Var(flag_rerun_cse_after_loop) Optimization
1652 Add a common subexpression elimination pass after loop optimizations
1656 Does nothing. Preserved for backward compatibility.
1659 Common Report Var(flag_rounding_math) Optimization SetByCombined
1660 Disable optimizations that assume default FP rounding behavior
1663 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1664 Enable scheduling across basic blocks
1667 Common Report Var(flag_sched_pressure) Init(0) Optimization
1668 Enable register pressure sensitive insn scheduling
1671 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1672 Allow speculative motion of non-loads
1675 Common Report Var(flag_schedule_speculative_load) Optimization
1676 Allow speculative motion of some loads
1678 fsched-spec-load-dangerous
1679 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1680 Allow speculative motion of more loads
1683 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1684 -fsched-verbose=<number> Set the verbosity level of the scheduler
1686 fsched2-use-superblocks
1687 Common Report Var(flag_sched2_use_superblocks) Optimization
1688 If scheduling post reload, do superblock scheduling
1692 Does nothing. Preserved for backward compatibility.
1695 Common Report Var(flag_schedule_insns) Optimization
1696 Reschedule instructions before register allocation
1699 Common Report Var(flag_schedule_insns_after_reload) Optimization
1700 Reschedule instructions after register allocation
1702 ; This flag should be on when a target implements non-trivial
1703 ; scheduling hooks, maybe saving some information for its own sake.
1704 ; On IA64, for example, this is used for correct bundling.
1705 fselective-scheduling
1706 Common Report Var(flag_selective_scheduling) Optimization
1707 Schedule instructions using selective scheduling algorithm
1709 fselective-scheduling2
1710 Common Report Var(flag_selective_scheduling2) Optimization
1711 Run selective scheduling after reload
1713 fsel-sched-pipelining
1714 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1715 Perform software pipelining of inner loops during selective scheduling
1717 fsel-sched-pipelining-outer-loops
1718 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1719 Perform software pipelining of outer loops during selective scheduling
1721 fsel-sched-reschedule-pipelined
1722 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1723 Reschedule pipelined regions without pipelining
1725 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1726 ; of stalled insns into the ready list.
1727 fsched-stalled-insns
1728 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1729 Allow premature scheduling of queued insns
1731 fsched-stalled-insns=
1732 Common RejectNegative Joined UInteger
1733 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1735 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1736 ; be examined for a dependency on a stalled insn that is candidate for
1737 ; premature removal from the queue of stalled insns into the ready list (has
1738 ; an effect only if the flag 'sched_stalled_insns' is set).
1739 fsched-stalled-insns-dep
1740 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1741 Set dependence distance checking in premature scheduling of queued insns
1743 fsched-stalled-insns-dep=
1744 Common RejectNegative Joined UInteger
1745 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1747 fsched-group-heuristic
1748 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1749 Enable the group heuristic in the scheduler
1751 fsched-critical-path-heuristic
1752 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1753 Enable the critical path heuristic in the scheduler
1755 fsched-spec-insn-heuristic
1756 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1757 Enable the speculative instruction heuristic in the scheduler
1759 fsched-rank-heuristic
1760 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1761 Enable the rank heuristic in the scheduler
1763 fsched-last-insn-heuristic
1764 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1765 Enable the last instruction heuristic in the scheduler
1767 fsched-dep-count-heuristic
1768 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1769 Enable the dependent count heuristic in the scheduler
1772 Common Report Var(flag_section_anchors) Optimization
1773 Access data in the same section from shared anchor points
1777 Does nothing. Preserved for backward compatibility.
1780 Common Report Var(flag_zee) Init(0)
1781 Eliminate redundant zero extensions on targets that support implicit extensions.
1784 Common Report Var(flag_show_column) Init(1)
1785 Show column numbers in diagnostics, when available. Default on
1788 Common Report Var(flag_shrink_wrap) Optimization
1789 Emit function prologues only before parts of the function that need it,
1790 rather than at the top of the function.
1793 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1794 Disable optimizations observable by IEEE signaling NaNs
1797 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1798 Disable floating point optimizations that ignore the IEEE signedness of zero
1800 fsingle-precision-constant
1801 Common Report Var(flag_single_precision_constant) Optimization
1802 Convert floating point constants to single precision constants
1804 fsplit-ivs-in-unroller
1805 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1806 Split lifetimes of induction variables when loops are unrolled
1809 Common Report Var(flag_split_stack) Init(-1)
1810 Generate discontiguous stack frames
1813 Common Report Var(flag_split_wide_types) Optimization
1814 Split wide types into independent registers
1816 fvariable-expansion-in-unroller
1817 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1818 Apply variable expansion when loops are unrolled
1821 Common Report RejectNegative Joined
1822 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1825 Common Alias(fstack-check=, specific, no)
1826 Insert stack checking code into the program. Same as -fstack-check=specific
1829 Common Var(common_deferred_options) Defer
1831 fstack-limit-register=
1832 Common RejectNegative Joined Var(common_deferred_options) Defer
1833 -fstack-limit-register=<register> Trap if the stack goes past <register>
1835 fstack-limit-symbol=
1836 Common RejectNegative Joined Var(common_deferred_options) Defer
1837 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1840 Common Report Var(flag_stack_protect, 1)
1841 Use propolice as a stack protection method
1843 fstack-protector-all
1844 Common Report RejectNegative Var(flag_stack_protect, 2)
1845 Use a stack protection method for every function
1848 Common RejectNegative Var(flag_stack_usage)
1849 Output stack usage information on a per-function basis
1853 Does nothing. Preserved for backward compatibility.
1855 ; Nonzero if we should do (language-dependent) alias analysis.
1856 ; Typically, this analysis will assume that expressions of certain
1857 ; types do not alias expressions of certain other types. Only used
1858 ; if alias analysis (in general) is enabled.
1860 Common Report Var(flag_strict_aliasing) Optimization
1861 Assume strict aliasing rules apply
1864 Common Report Var(flag_strict_overflow)
1865 Treat signed overflow as undefined
1868 Common Report Var(flag_syntax_only)
1869 Check for syntax errors, then stop
1872 Common Report Var(flag_test_coverage)
1873 Create data files needed by \"gcov\"
1876 Common Report Var(flag_thread_jumps) Optimization
1877 Perform jump threading optimizations
1880 Common Report Var(time_report)
1881 Report the time taken by each compiler pass
1884 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
1885 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
1888 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
1891 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
1894 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
1897 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
1900 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
1903 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1904 Reorder top level functions, variables, and asms
1907 Common Report Var(flag_tracer)
1908 Perform superblock formation via tail duplication
1910 ; Zero means that floating-point math operations cannot generate a
1911 ; (user-visible) trap. This is the case, for example, in nonstop
1912 ; IEEE 754 arithmetic.
1914 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
1915 Assume floating-point operations can trap
1918 Common Report Var(flag_trapv) Optimization
1919 Trap for signed overflow in addition, subtraction and multiplication
1922 Common Report Var(flag_tree_ccp) Optimization
1923 Enable SSA-CCP optimization on trees
1926 Common Report Var(flag_tree_bit_ccp) Optimization
1927 Enable SSA-BIT-CCP optimization on trees
1931 Does nothing. Preserved for backward compatibility.
1934 Common Report Var(flag_tree_ch) Optimization
1935 Enable loop header copying on trees
1938 Common Report Var(flag_tree_copyrename) Optimization
1939 Replace SSA temporaries with better names in copies
1942 Common Report Var(flag_tree_copy_prop) Optimization
1943 Enable copy propagation on trees
1945 ftree-store-copy-prop
1947 Does nothing. Preserved for backward compatibility.
1950 Common Report Var(flag_tree_cselim) Init(2) Optimization
1951 Transform condition stores into unconditional ones
1953 ftree-switch-conversion
1954 Common Report Var(flag_tree_switch_conversion) Optimization
1955 Perform conversions of switch initializations.
1958 Common Report Var(flag_tree_dce) Optimization
1959 Enable SSA dead code elimination optimization on trees
1961 ftree-dominator-opts
1962 Common Report Var(flag_tree_dom) Optimization
1963 Enable dominator optimizations
1966 Common Report Var(flag_tree_tail_merge) Optimization
1967 Enable tail merging on trees
1970 Common Report Var(flag_tree_dse) Optimization
1971 Enable dead store elimination
1974 Common Report Var(flag_tree_forwprop) Init(1) Optimization
1975 Enable forward propagation on trees
1978 Common Report Var(flag_tree_fre) Optimization
1979 Enable Full Redundancy Elimination (FRE) on trees
1982 Common Report Var(flag_optimize_strlen) Optimization
1983 Enable string length optimizations on trees
1985 ftree-loop-distribution
1986 Common Report Var(flag_tree_loop_distribution) Optimization
1987 Enable loop distribution on trees
1989 ftree-loop-distribute-patterns
1990 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
1991 Enable loop distribution for patterns transformed into a library call
1994 Common Report Var(flag_tree_loop_im) Init(1) Optimization
1995 Enable loop invariant motion on trees
1998 Common Alias(floop-interchange)
1999 Enable loop interchange transforms. Same as -floop-interchange
2002 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2003 Create canonical induction variables in loops
2006 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2007 Enable loop optimizations on tree level
2009 ftree-parallelize-loops=
2010 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2011 Enable automatic parallelization of loops
2014 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2015 Enable hoisting loads from conditional pointers.
2018 Common Report Var(flag_tree_pre) Optimization
2019 Enable SSA-PRE optimization on trees
2022 Common Report Var(flag_tree_pta) Init(1) Optimization
2023 Perform function-local points-to analysis on trees.
2026 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2027 Enable reassociation on tree level
2031 Does nothing. Preserved for backward compatibility.
2034 Common Report Var(flag_tree_sink) Optimization
2035 Enable SSA code sinking on trees
2038 Common Report Var(flag_tree_sra) Optimization
2039 Perform scalar replacement of aggregates
2042 Common Report Var(flag_tree_ter) Optimization
2043 Replace temporary expressions in the SSA->normal pass
2046 Common Report Var(flag_tree_live_range_split) Optimization
2047 Perform live range splitting during the SSA->normal pass
2050 Common Report Var(flag_tree_vrp) Init(0) Optimization
2051 Perform Value Range Propagation on trees
2054 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2055 Compile whole compilation unit at a time
2058 Common Report Var(flag_unroll_loops) Optimization
2059 Perform loop unrolling when iteration count is known
2062 Common Report Var(flag_unroll_all_loops) Optimization
2063 Perform loop unrolling for all loops
2065 ; Nonzero means that loop optimizer may assume that the induction variables
2066 ; that control loops do not overflow and that the loops with nontrivial
2067 ; exit condition are not infinite
2068 funsafe-loop-optimizations
2069 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2070 Allow loop optimizations to assume that the loops behave in normal way
2073 Common Report Var(flag_associative_math) SetByCombined
2074 Allow optimization for floating-point arithmetic which may change the
2075 result of the operation due to rounding.
2078 Common Report Var(flag_reciprocal_math) SetByCombined
2079 Same as -fassociative-math for expressions which include division.
2081 ; Nonzero means that unsafe floating-point math optimizations are allowed
2082 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2083 ; are allowed to assume that their arguments and results are "normal"
2084 ; (e.g., nonnegative for SQRT).
2085 funsafe-math-optimizations
2086 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2087 Allow math optimizations that may violate IEEE or ISO standards
2090 Common Report Var(flag_unswitch_loops) Optimization
2091 Perform loop unswitching
2094 Common Report Var(flag_unwind_tables) Optimization
2095 Just generate unwind tables for exception handling
2100 ; Positive if we should track variables, negative if we should run
2101 ; the var-tracking pass only to discard debug annotations, zero if
2102 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2103 ; will be set according to optimize, debug_info_level and debug_hooks
2104 ; in process_options ().
2106 Common Report Var(flag_var_tracking) Init(2) Optimization
2107 Perform variable tracking
2109 ; Positive if we should track variables at assignments, negative if
2110 ; we should run the var-tracking pass only to discard debug
2111 ; annotations. When flag_var_tracking_assignments ==
2112 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2113 fvar-tracking-assignments
2114 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2115 Perform variable tracking by annotating assignments
2117 ; Nonzero if we should toggle flag_var_tracking_assignments after
2118 ; processing options and computing its default. */
2119 fvar-tracking-assignments-toggle
2120 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2121 Toggle -fvar-tracking-assignments
2123 fvar-tracking-uninit
2124 Common Report Var(flag_var_tracking_uninit) Optimization
2125 Perform variable tracking and also tag variables that are uninitialized
2128 Common Report Var(flag_tree_vectorize) Optimization
2129 Enable loop vectorization on trees
2132 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2133 Enable basic block vectorization (SLP) on trees
2136 Common Report Var(flag_vect_cost_model) Optimization
2137 Enable use of cost model in vectorization
2139 ftree-vect-loop-version
2140 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2141 Enable loop versioning when doing loop vectorization on trees
2143 ftree-vectorizer-verbose=
2144 Common RejectNegative Joined UInteger
2145 -ftree-vectorizer-verbose=<number> Set the verbosity level of the vectorizer
2148 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2149 Enable copy propagation of scalar-evolution information.
2151 ; -fverbose-asm causes extra commentary information to be produced in
2152 ; the generated assembly code (to make it more readable). This option
2153 ; is generally only of use to those who actually need to read the
2154 ; generated assembly code (perhaps while debugging the compiler itself).
2155 ; -fno-verbose-asm, the default, causes the extra information
2156 ; to not be added and is useful when comparing two assembler files.
2158 Common Report Var(flag_verbose_asm)
2159 Add extra commentary to assembler output
2162 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2163 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2166 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2169 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2172 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2175 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2178 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2181 Common Report Var(flag_value_profile_transformations) Optimization
2182 Use expression value profiles in optimizations
2185 Common Report Var(flag_web) Init(2) Optimization
2186 Construct webs and split unrelated uses of single variable
2188 ftree-builtin-call-dce
2189 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2190 Enable conditional dead code elimination for builtin calls
2193 Common Report Var(flag_whole_program) Init(0) Optimization
2194 Perform whole program optimizations
2197 Common Report Var(flag_wrapv) Optimization
2198 Assume signed arithmetic overflow wraps around
2200 fzero-initialized-in-bss
2201 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2202 Put zero initialized data in the bss section
2205 Common JoinedOrMissing
2206 Generate debug information in default format
2209 Common JoinedOrMissing Negative(gdwarf-)
2210 Generate debug information in COFF format
2213 Common Joined UInteger Var(dwarf_version) Init(2) Negative(gstabs)
2214 Generate debug information in DWARF v2 (or later) format
2217 Common JoinedOrMissing
2218 Generate debug information in default extended format
2220 gno-record-gcc-switches
2221 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(0)
2222 Don't record gcc command line switches in DWARF DW_AT_producer.
2224 grecord-gcc-switches
2225 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2226 Record gcc command line switches in DWARF DW_AT_producer.
2229 Common JoinedOrMissing Negative(gstabs+)
2230 Generate debug information in STABS format
2233 Common JoinedOrMissing Negative(gvms)
2234 Generate debug information in extended STABS format
2237 Common RejectNegative Var(dwarf_strict,0) Init(-1)
2238 Emit DWARF additions beyond selected version
2241 Common Report RejectNegative Var(dwarf_strict,1)
2242 Don't emit DWARF additions beyond selected version
2245 Common Report Var(flag_gtoggle)
2246 Toggle debug information generation
2249 Common JoinedOrMissing Negative(gxcoff)
2250 Generate debug information in VMS format
2253 Common JoinedOrMissing Negative(gxcoff+)
2254 Generate debug information in XCOFF format
2257 Common JoinedOrMissing Negative(gcoff)
2258 Generate debug information in extended XCOFF format
2261 Driver Joined Separate
2264 Common Joined Var(plugindir_string) Init(0)
2265 -iplugindir=<dir> Set <dir> to be the default plugin directory
2268 Driver Joined Separate
2273 no-canonical-prefixes
2286 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2287 -o <file> Place output into <file>
2290 Common Var(profile_flag)
2291 Enable function profiling
2294 Driver Var(pass_exit_codes)
2297 Common Var(pedantic)
2298 Issue warnings needed for strict compliance to the standard
2301 Common Var(flag_pedantic_errors)
2302 Like -pedantic but issue them as errors
2308 Driver Var(use_pipes)
2311 Driver JoinedOrMissing Var(print_file_name)
2313 print-libgcc-file-name
2316 print-multi-directory
2317 Driver Var(print_multi_directory)
2320 Driver Var(print_multi_lib)
2322 print-multi-os-directory
2323 Driver Var(print_multi_os_directory)
2326 Driver JoinedOrMissing Var(print_prog_name)
2329 Driver Var(print_search_dirs)
2332 Driver Var(print_sysroot)
2334 print-sysroot-headers-suffix
2335 Driver Var(print_sysroot_headers_suffix)
2338 Common Var(quiet_flag) RejectDriver
2339 Do not display functions compiled or elapsed time
2357 Driver Var(report_times)
2360 Driver JoinedOrMissing
2363 Driver Joined Separate
2367 ; C option, but driver must not handle as "-u ndef".
2370 Common Driver Var(verbose_flag)
2371 Enable verbose output
2374 Common Var(version_flag) RejectDriver
2375 Display the compiler's version
2378 Common Var(inhibit_warnings)
2382 Driver Separate Var(wrapper_string)
2385 Driver Joined Separate
2388 Common RejectNegative Negative(pie)
2389 Create a shared library
2395 Driver Separate Alias(specs=)
2408 ; Documented for Fortran, but always accepted by driver.
2415 ; Documented for Go, but always accepted by driver.
2421 Common RejectNegative Negative(shared)
2422 Create a position independent executable
2425 Driver Joined Separate
2427 ; This comment is to ensure we retain the blank line above.