1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
4 ; Free Software Foundation, Inc.
6 ; This file is part of GCC.
8 ; GCC is free software; you can redistribute it and/or modify it under
9 ; the terms of the GNU General Public License as published by the Free
10 ; Software Foundation; either version 3, or (at your option) any later
13 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 ; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 ; You should have received a copy of the GNU General Public License
19 ; along with GCC; see the file COPYING3. If not see
20 ; <http://www.gnu.org/licenses/>.
22 ; See the GCC internals manual (options.texi) for a description of this file's format.
24 ; Please try to keep this file in ASCII collating order.
38 ; Not used directly to control optimizations, only to save -Ofast
39 ; setting for "optimize" attributes.
43 ; True if this is the lto front end. This is used to disable gimple
44 ; generation and lowering passes that are normally run on the output
45 ; of a front end. These passes must be bypassed for lto since they
46 ; have already been done before the gimple was written.
50 ; 0 means straightforward implementation of complex divide acceptable.
51 ; 1 means wide ranges of inputs must work for complex divide.
52 ; 2 means C99-like requirements for complex multiply and divide.
54 int flag_complex_method = 1
56 ; Nonzero if subexpressions must be evaluated from left-to-right.
58 int flag_evaluation_order = 0
60 ; Language specific warning pass for unused results.
62 bool flag_warn_unused_result = false
67 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
71 ; True to warn about any objects definitions whose size is larger
72 ; than N bytes. Also want about function definitions whose returned
73 ; values are larger than N bytes, where N is 'larger_than_size'.
78 HOST_WIDE_INT larger_than_size
80 ; True to warn about any function whose frame size is larger
83 bool warn_frame_larger_than
86 HOST_WIDE_INT frame_larger_than_size
88 ; Nonzero means we should be saving declaration info into a .X file.
90 int flag_gen_aux_info = 0
92 ; Nonzero if we are compiling code for a shared library, zero for
97 ; These two are really VEC(char_p,heap) *.
100 void *flag_instrument_functions_exclude_functions
103 void *flag_instrument_functions_exclude_files
105 ; Generic structs (e.g. templates not explicitly specialized)
106 ; may not have a compilation unit associated with them, and so
107 ; may need to be treated differently from ordinary structs.
109 ; Structs only handled by reference (indirectly), will also usually
110 ; not need as much debugging information.
113 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
116 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
118 ; True if we should exit after parsing options.
120 bool exit_after_options
122 ; Type(s) of debugging information we are producing (if any). See
123 ; flag-types.h for the definitions of the different possible types of
124 ; debugging information.
126 enum debug_info_type write_symbols = NO_DEBUG
128 ; Level of debugging information we are producing. See flag-types.h
129 ; for the definitions of the different possible levels.
131 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
133 ; Nonzero means use GNU-only extensions in the generated symbolic
134 ; debugging information. Currently, this only has an effect when
135 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
137 bool use_gnu_debug_info_extensions
139 ; Original value of maximum field alignment in bytes, specified via
140 ; -fpack-struct=<value>.
142 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
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)
295 Driver Var(no_sysroot_suffix)
304 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
307 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
310 Driver Alias(pass-exit-codes)
313 Common Alias(Wpedantic)
316 Common Alias(pedantic-errors)
325 Driver Separate Alias(B)
328 Driver JoinedOrMissing Alias(B)
334 Driver Separate Alias(print-file-name=)
337 Driver JoinedOrMissing Alias(print-file-name=)
339 -print-libgcc-file-name
340 Driver Alias(print-libgcc-file-name)
342 -print-multi-directory
343 Driver Alias(print-multi-directory)
346 Driver Alias(print-multi-lib)
348 -print-multi-os-directory
349 Driver Alias(print-multi-os-directory)
352 Driver Separate Alias(print-prog-name=)
355 Driver JoinedOrMissing Alias(print-prog-name=)
358 Driver Alias(print-search-dirs)
361 Driver Alias(print-sysroot)
363 -print-sysroot-headers-suffix
364 Driver Alias(print-sysroot-headers-suffix)
370 Driver Alias(save-temps)
376 Driver Separate Alias(specs=)
379 Driver Joined Alias(specs=)
385 Driver Alias(symbolic)
389 Alias for --help=target
397 ;; The driver used to convert options such as --help into forms such
398 ;; as -fhelp; the following four entries are for compatibility with
399 ;; any direct uses of those (undocumented) -f forms
401 Common Driver Alias(-help)
404 Common Driver Joined Alias(-help=)
407 Common Driver Alias(-target-help)
410 Common Driver Alias(-version)
414 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
417 Common Joined Alias(-param)
420 Driver Separate Alias(-sysroot=)
423 Driver JoinedOrMissing
429 Driver Joined Separate
435 Driver Joined Separate
441 Common JoinedOrMissing Optimization
442 -O<number> Set optimization level to <number>
446 Optimize for space rather than speed
450 Optimize for speed disregarding exact standards compliance
454 Optimize for debugging experience rather than speed or size
466 Driver Joined Separate
472 Driver Joined Separate
493 Common RejectNegative Warning Alias(Wextra)
494 This switch is deprecated; use -Wextra instead
497 Driver JoinedOrMissing
500 Driver JoinedOrMissing
503 Driver JoinedOrMissing
506 Common Var(warn_aggregate_return) Warning
507 Warn about returning structures, unions or arrays
510 Common Var(warn_array_bounds) Warning
511 Warn if an array is accessed out of bounds
514 Common Var(warn_attributes) Init(1) Warning
515 Warn about inappropriate attribute usage
518 Common Var(warn_cast_align) Warning
519 Warn about pointer casts which increase alignment
522 Common Var(warn_cpp) Init(1) Warning
523 Warn when a #warning directive is encountered
525 Wdeprecated-declarations
526 Common Var(warn_deprecated_decl) Init(1) Warning
527 Warn about uses of __attribute__((deprecated)) declarations
529 Wdisabled-optimization
530 Common Var(warn_disabled_optimization) Warning
531 Warn when an optimization pass is disabled
534 Common Var(warnings_are_errors)
535 Treat all warnings as errors
539 Treat specified warning as error
542 Common Var(extra_warnings) Warning
543 Print extra (possibly unwanted) warnings
546 Common Var(flag_fatal_errors)
547 Exit on the first error occurred
550 Common RejectNegative Joined UInteger
551 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
554 Common Var(warn_free_nonheap_object) Init(1) Warning
555 Warn when attempting to free a non-heap object
558 Common Var(warn_inline) Warning
559 Warn when an inlined function cannot be inlined
561 Winvalid-memory-model
562 Common Var(warn_invalid_memory_model) Init(1) Warning
563 Warn when an atomic memory model parameter is known to be outside the valid range.
566 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
569 Common RejectNegative Joined UInteger Warning
570 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
572 Wunsafe-loop-optimizations
573 Common Var(warn_unsafe_loop_optimizations) Warning
574 Warn if the loop cannot be optimized due to nontrivial assumptions.
577 Common Alias(Wsuggest-attribute=noreturn)
580 Common Var(warn_overflow) Init(1) Warning
581 Warn about overflow in arithmetic expressions
584 Common Var(warn_packed) Warning
585 Warn when the packed attribute has no effect on struct layout
588 Common Var(warn_padded) Warning
589 Warn when padding is required to align structure members
592 Common Var(pedantic) Warning
593 Issue warnings needed for strict compliance to the standard
596 Common Var(warn_shadow) Warning
597 Warn when one local variable shadows another
600 Common Var(warn_stack_protect) Warning
601 Warn when not issuing stack smashing protection for some reason
604 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
605 Warn if stack usage might be larger than specified amount
609 Warn about code which might break strict aliasing rules
612 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Init(-1) Warning
613 Warn about code which might break strict aliasing rules
617 Warn about optimizations that assume that signed overflow is undefined
620 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Init(-1) Warning
621 Warn about optimizations that assume that signed overflow is undefined
623 Wsuggest-attribute=const
624 Common Var(warn_suggest_attribute_const) Warning
625 Warn about functions which might be candidates for __attribute__((const))
627 Wsuggest-attribute=pure
628 Common Var(warn_suggest_attribute_pure) Warning
629 Warn about functions which might be candidates for __attribute__((pure))
631 Wsuggest-attribute=noreturn
632 Common Var(warn_suggest_attribute_noreturn) Warning
633 Warn about functions which might be candidates for __attribute__((noreturn))
636 Common Var(warn_switch) Warning
637 Warn about enumerated switches, with no default, missing a case
640 Common Var(warn_switch_default) Warning
641 Warn about enumerated switches missing a \"default:\" statement
644 Common Var(warn_switch_enum) Warning
645 Warn about all enumerated switches missing a specific case
648 Common Var(warn_system_headers) Warning
649 Do not suppress warnings from system headers
652 Common Var(warn_trampolines) Warning
653 Warn whenever a trampoline is generated
656 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
657 Warn if a comparison is always true or always false due to the limited range of the data type
660 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
661 Warn about uninitialized automatic variables
664 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
665 Warn about maybe uninitialized automatic variables
669 Does nothing. Preserved for backward compatibility.
672 Common Var(warn_unused) Init(0) Warning
673 Enable all -Wunused- warnings
675 Wunused-but-set-parameter
676 Common Var(warn_unused_but_set_parameter) Init(-1) Warning
677 Warn when a function parameter is only set, otherwise unused
679 Wunused-but-set-variable
680 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
681 Warn when a variable is only set, otherwise unused
684 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
685 Warn when a function is unused
688 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
689 Warn when a label is unused
692 Common Var(warn_unused_parameter) Init(-1) Warning
693 Warn when a function parameter is unused
696 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
697 Warn when an expression value is unused
700 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
701 Warn when a variable is unused
704 Common Var(warn_coverage_mismatch) Init(1) Warning
705 Warn in case profiles in -fprofile-use do not match
707 Wvector-operation-performance
708 Common Var(warn_vector_operation_performance) Warning
709 Warn when a vector operation is compiled outside the SIMD
724 Common Separate Var(aux_info_file_name)
725 -aux-info <file> Emit declaration information into <file>
728 Common Joined Alias(aux-info)
731 Common Separate RejectDriver Var(aux_base_name)
734 Common Separate RejectDriver
744 -d<letters> Enable dumps from specific passes of the compiler
747 Common Separate Var(dump_base_name)
748 -dumpbase <file> Set the file basename to be used for dumps
751 Common Separate Var(dump_dir_name)
752 -dumpdir <dir> Set the directory name to be used for dumps
764 Driver Joined Separate
766 ; This option has historically been passed down to the linker by an
767 ; accident of a %{e*} spec, so ensure it continues to be passed down
768 ; as a single option. The supported option for this purpose is
769 ; -rdynamic. See PR 47390.
773 ; The version of the C++ ABI in use. The following values are allowed:
775 ; 0: The version of the ABI believed most conformant with the C++ ABI
776 ; specification. This ABI may change as bugs are discovered and fixed.
777 ; Therefore, 0 will not necessarily indicate the same ABI in different
780 ; 1: The version of the ABI first used in G++ 3.2.
782 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
784 ; 3: The version of the ABI that fixes the missing underscore
785 ; in template non-type arguments of pointer type.
787 ; 4: The version of the ABI that introduces unambiguous mangling of
788 ; vector types. First selectable in G++ 4.5.
790 ; 5: The version of the ABI that ignores attribute const/noreturn
791 ; in function pointer mangling, and corrects mangling of decltype and
792 ; function parameters used in other parameters and the return type.
793 ; First selectable in G++ 4.6.
795 ; 6: The version of the ABI that doesn't promote scoped enums to int and
796 ; changes the mangling of template argument packs, const/static_cast,
797 ; prefix ++ and --, and a class scope function used as a template
799 ; First selectable in G++ 4.7.
801 ; 7: The version of the ABI that treats nullptr_t as a builtin type.
802 ; First selectable in G++ 4.8.
803 ; Additional positive integers will be assigned as new versions of
804 ; the ABI become the default version of the ABI.
806 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
809 Common Report Var(align_functions,0) Optimization UInteger
810 Align the start of functions
813 Common RejectNegative Joined UInteger Var(align_functions)
816 Common Report Var(align_jumps,0) Optimization UInteger
817 Align labels which are only reached by jumping
820 Common RejectNegative Joined UInteger Var(align_jumps)
823 Common Report Var(align_labels,0) Optimization UInteger
827 Common RejectNegative Joined UInteger Var(align_labels)
830 Common Report Var(align_loops,0) Optimization UInteger
831 Align the start of loops
834 Common RejectNegative Joined UInteger Var(align_loops)
838 Does nothing. Preserved for backward compatibility.
842 Does nothing. Preserved for backward compatibility.
844 fargument-noalias-global
846 Does nothing. Preserved for backward compatibility.
848 fargument-noalias-anything
850 Does nothing. Preserved for backward compatibility.
852 fasynchronous-unwind-tables
853 Common Report Var(flag_asynchronous_unwind_tables) Optimization
854 Generate unwind tables that are exact at each instruction boundary
857 Common Report Var(flag_auto_inc_dec) Init(1)
858 Generate auto-inc/dec instructions
860 ; -fcheck-bounds causes gcc to generate array bounds checks.
861 ; For C, C++ and ObjC: defaults off.
862 ; For Java: defaults to on.
863 ; For Fortran: defaults to off.
865 Common Report Var(flag_bounds_check)
866 Generate code to check bounds before indexing arrays
869 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
870 Replace add, compare, branch with branch on count register
872 fbranch-probabilities
873 Common Report Var(flag_branch_probabilities) Optimization
874 Use profiling information for branch probabilities
876 fbranch-target-load-optimize
877 Common Report Var(flag_branch_target_load_optimize) Optimization
878 Perform branch target load optimization before prologue / epilogue threading
880 fbranch-target-load-optimize2
881 Common Report Var(flag_branch_target_load_optimize2) Optimization
882 Perform branch target load optimization after prologue / epilogue threading
885 Common Report Var(flag_btr_bb_exclusive) Optimization
886 Restrict target load migration not to re-use registers in any basic block
889 Common Joined RejectNegative Var(common_deferred_options) Defer
890 -fcall-saved-<register> Mark <register> as being preserved across functions
893 Common Joined RejectNegative Var(common_deferred_options) Defer
894 -fcall-used-<register> Mark <register> as being corrupted by function calls
896 ; Nonzero for -fcaller-saves: allocate values in regs that need to
897 ; be saved across function calls, if that produces overall better code.
898 ; Optional now, so people can test it.
900 Common Report Var(flag_caller_saves) Optimization
901 Save registers around function calls
904 Common Report Var(flag_check_data_deps)
905 Compare the results of several data dependence analyzers.
907 fcombine-stack-adjustments
908 Common Report Var(flag_combine_stack_adjustments) Optimization
909 Looks for opportunities to reduce stack adjustments and stack references.
912 Common Report Var(flag_no_common,0) Optimization
913 Do not put uninitialized globals in the common section
917 ; Converted by the driver to -fcompare-debug= options.
920 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
921 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
923 fcompare-debug-second
924 Common Driver RejectNegative Var(flag_compare_debug)
925 Run only the second compilation of -fcompare-debug
928 Common Report Var(flag_compare_elim_after_reload) Optimization
929 Perform comparison elimination after register allocation has finished
932 Common Var(flag_conserve_stack) Optimization
933 Do not perform optimizations increasing noticeably stack usage
936 Common Report Var(flag_cprop_registers) Optimization
937 Perform a register copy-propagation optimization pass
940 Common Report Var(flag_crossjumping) Optimization
941 Perform cross-jumping optimization
944 Common Report Var(flag_cse_follow_jumps) Optimization
945 When running CSE, follow jumps to their targets
949 Does nothing. Preserved for backward compatibility.
952 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
953 Omit range reduction step when performing complex division
956 Common Report Var(flag_cx_fortran_rules) Optimization
957 Complex multiplication and division follow Fortran rules
960 Common Report Var(flag_data_sections) Optimization
961 Place data items into their own section
964 Common Report Var(common_deferred_options) Defer
965 List all available debugging counters with their limits and counts.
968 Common RejectNegative Joined Var(common_deferred_options) Defer
969 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
972 Common Joined RejectNegative Var(common_deferred_options) Defer
973 Map one directory name to another in debug information
976 Common Report Var(flag_debug_types_section) Init(0)
977 Output .debug_types section when using DWARF v4 debuginfo.
979 ; Nonzero for -fdefer-pop: don't pop args after each function call
980 ; instead save them up to pop many calls' args with one insns.
982 Common Report Var(flag_defer_pop) Optimization
983 Defer popping functions args from stack until later
986 Common Report Var(flag_delayed_branch) Optimization
987 Attempt to fill delay slots of branch instructions
989 fdelete-dead-exceptions
990 Common Report Var(flag_delete_dead_exceptions) Init(0)
991 Delete dead instructions that may throw exceptions
993 fdelete-null-pointer-checks
994 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
995 Delete useless null pointer checks
998 Common Report Var(flag_devirtualize) Optimization
999 Try to convert virtual calls to direct ones.
1001 fdiagnostics-show-location=
1002 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1003 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
1005 ; Required for these enum values.
1010 Name(diagnostic_prefixing_rule) Type(int)
1013 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1016 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1018 fdiagnostics-show-caret
1019 Common Var(flag_diagnostics_show_caret) Init(1)
1020 Show the source line with a caret indicating the column
1022 fdiagnostics-show-option
1023 Common Var(flag_diagnostics_show_option) Init(1)
1024 Amend appropriate diagnostic messages with the command line option that controls them
1027 Common Joined RejectNegative Var(common_deferred_options) Defer
1028 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass
1031 Common Joined RejectNegative Var(common_deferred_options) Defer
1032 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass
1035 Common Joined RejectNegative Var(common_deferred_options) Defer
1036 -fdump-<type> Dump various compiler internals to a file
1039 Driver RejectNegative
1042 Common RejectNegative Joined Var(flag_dump_final_insns)
1043 -fdump-final-insns=filename Dump to filename the insns at the end of translation
1046 Common RejectNegative Joined Var(flag_dump_go_spec)
1047 -fdump-go-spec=filename Write all declarations to file as Go code
1050 Common Report Var(flag_dump_noaddr)
1051 Suppress output of addresses in debugging dumps
1054 Common Var(flag_dump_passes) Init(0)
1055 Dump optimization passes
1058 Common Report Var(flag_dump_unnumbered)
1059 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
1061 fdump-unnumbered-links
1062 Common Report Var(flag_dump_unnumbered_links)
1063 Suppress output of previous and next insn numbers in debugging dumps
1066 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1067 Enable CFI tables via GAS assembler directives.
1070 Common Report Var(flag_early_inlining) Init(1) Optimization
1071 Perform early inlining
1073 feliminate-dwarf2-dups
1074 Common Report Var(flag_eliminate_dwarf2_dups)
1075 Perform DWARF2 duplicate elimination
1078 Common Report Var(flag_ipa_sra) Init(0) Optimization
1079 Perform interprocedural reduction of aggregates
1081 feliminate-unused-debug-symbols
1082 Common Report Var(flag_debug_only_used_symbols)
1083 Perform unused type elimination in debug info
1085 feliminate-unused-debug-types
1086 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1087 Perform unused type elimination in debug info
1089 femit-class-debug-always
1090 Common Report Var(flag_emit_class_debug_always) Init(0)
1091 Do not suppress C++ class debug information.
1094 Common Report Var(flag_exceptions) Optimization
1095 Enable exception handling
1097 fexpensive-optimizations
1098 Common Report Var(flag_expensive_optimizations) Optimization
1099 Perform a number of minor, expensive optimizations
1102 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1103 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1106 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1109 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1112 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1118 Common Var(flag_fat_lto_objects) Init(1)
1119 Output lto objects containing both the intermediate language and binary output.
1122 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1123 Assume no NaNs or infinities are generated
1126 Common Joined RejectNegative Var(common_deferred_options) Defer
1127 -ffixed-<register> Mark <register> as being unavailable to the compiler
1130 Common Report Var(flag_float_store) Optimization
1131 Don't allocate floats and doubles in extended-precision registers
1135 Does nothing. Preserved for backward compatibility.
1138 Common Report Var(flag_forward_propagate) Optimization
1139 Perform a forward propagation pass on RTL
1142 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1143 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1146 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1149 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1151 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1153 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1156 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1158 ; Nonzero means don't put addresses of constant functions in registers.
1159 ; Used for compiling the Unix kernel, where strange substitutions are
1160 ; done on the assembly output.
1162 Common Report Var(flag_no_function_cse,0)
1163 Allow function addresses to be held in registers
1166 Common Report Var(flag_function_sections)
1167 Place each function into its own section
1170 Common Report Var(flag_gcse) Optimization
1171 Perform global common subexpression elimination
1174 Common Report Var(flag_gcse_lm) Init(1) Optimization
1175 Perform enhanced load motion during global common subexpression elimination
1178 Common Report Var(flag_gcse_sm) Init(0) Optimization
1179 Perform store motion after global common subexpression elimination
1182 Common Report Var(flag_gcse_las) Init(0) Optimization
1183 Perform redundant load after store elimination in global common subexpression
1187 Common Report Var(flag_gcse_after_reload) Optimization
1188 Perform global common subexpression elimination after register allocation
1191 ; This option is not documented yet as its semantics will change.
1193 Common Report Var(flag_graphite)
1194 Enable in and out of Graphite representation
1197 Common Report Var(flag_graphite_identity) Optimization
1198 Enable Graphite Identity transformation
1200 fhoist-adjacent-loads
1201 Common Report Var(flag_hoist_adjacent_loads) Optimization
1202 Enable hoisting adjacent loads to encourage generating conditional move
1205 floop-parallelize-all
1206 Common Report Var(flag_loop_parallelize_all) Optimization
1207 Mark all loops as parallel
1210 Common Report Var(flag_loop_strip_mine) Optimization
1211 Enable Loop Strip Mining transformation
1214 Common Report Var(flag_loop_interchange) Optimization
1215 Enable Loop Interchange transformation
1218 Common Report Var(flag_loop_block) Optimization
1219 Enable Loop Blocking transformation
1222 Common Report Var(flag_tm)
1223 Enable support for GNU transactional memory
1227 Does nothing. Preserved for backward compatibility.
1230 Common Report Var(flag_loop_optimize_isl) Optimization
1231 Enable the ISL based loop nest optimizer
1233 fstrict-volatile-bitfields
1234 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1235 Force bitfield accesses to match their type width
1237 fguess-branch-probability
1238 Common Report Var(flag_guess_branch_prob) Optimization
1239 Enable guessing of branch probabilities
1241 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1242 ; Generate position-independent code for executables if possible
1243 ; On SVR4 targets, it also controls whether or not to emit a
1244 ; string identifying the compiler.
1246 Common Report Var(flag_no_ident,0)
1247 Process #ident directives
1250 Common Report Var(flag_if_conversion) Optimization
1251 Perform conversion of conditional jumps to branchless equivalents
1254 Common Report Var(flag_if_conversion2) Optimization
1255 Perform conversion of conditional jumps to conditional execution
1258 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL)
1259 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1262 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1265 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1268 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1271 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1273 ftree-loop-if-convert
1274 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1275 Convert conditional jumps in innermost loops to branchless equivalents
1277 ftree-loop-if-convert-stores
1278 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1279 Also if-convert conditional jumps containing memory writes
1281 ; -finhibit-size-directive inhibits output of .size for ELF.
1282 ; This is used only for compiling crtstuff.c,
1283 ; and it may be extended to other effects
1284 ; needed for crtstuff.c on other systems.
1285 finhibit-size-directive
1286 Common Report Var(flag_inhibit_size_directive)
1287 Do not generate .size directives
1290 Common Report Var(flag_indirect_inlining)
1291 Perform indirect inlining
1293 ; General flag to enable inlining. Specifying -fno-inline will disable
1294 ; all inlining apart from always-inline functions.
1296 Common Report Var(flag_no_inline,0) Init(0) Optimization
1297 Enable inlining of function declared \"inline\", disabling disables all inlining
1299 finline-small-functions
1300 Common Report Var(flag_inline_small_functions) Optimization
1301 Integrate functions into their callers when code size is known not to grow
1304 Common Report Var(flag_inline_functions) Optimization
1305 Integrate functions not declared \"inline\" into their callers when profitable
1307 finline-functions-called-once
1308 Common Report Var(flag_inline_functions_called_once) Optimization
1309 Integrate functions only required by their single caller
1312 Common RejectNegative Joined Alias(finline-limit=)
1315 Common RejectNegative Joined UInteger
1316 -finline-limit=<number> Limit the size of inlined functions to <number>
1319 Common Report Var(flag_inline_atomics) Init(1) Optimization
1320 Inline __atomic operations when a lock free instruction sequence is available.
1322 finstrument-functions
1323 Common Report Var(flag_instrument_function_entry_exit)
1324 Instrument function entry and exit with profiling calls
1326 finstrument-functions-exclude-function-list=
1327 Common RejectNegative Joined
1328 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1330 finstrument-functions-exclude-file-list=
1331 Common RejectNegative Joined
1332 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1335 Common Report Var(flag_ipa_cp) Optimization
1336 Perform Interprocedural constant propagation
1339 Common Report Var(flag_ipa_cp_clone) Optimization
1340 Perform cloning to make Interprocedural constant propagation stronger
1343 Common Report Var(flag_ipa_profile) Init(0) Optimization
1344 Perform interprocedural profile propagation
1347 Common Report Var(flag_ipa_pta) Init(0) Optimization
1348 Perform interprocedural points-to analysis
1351 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1352 Discover pure and const functions
1355 Common Report Var(flag_ipa_reference) Init(0) Optimization
1356 Discover readonly and non addressable static variables
1360 Does nothing. Preserved for backward compatibility.
1364 Does nothing. Preserved for backward compatibility.
1367 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1368 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1371 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1374 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1377 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1380 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT)
1381 -fira-region=[one|all|mixed] Set regions for IRA
1384 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1387 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1390 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1393 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1396 Common Report Var(flag_ira_loop_pressure)
1397 Use IRA based register pressure calculation
1398 in RTL loop optimizations.
1400 fira-share-save-slots
1401 Common Report Var(flag_ira_share_save_slots) Init(1)
1402 Share slots for saving different hard registers.
1404 fira-share-spill-slots
1405 Common Report Var(flag_ira_share_spill_slots) Init(1)
1406 Share stack slots for spilled pseudo-registers.
1409 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1410 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1413 Common Report Var(flag_ivopts) Init(1) Optimization
1414 Optimize induction variables on trees
1417 Common Var(flag_jump_tables) Init(1) Optimization
1418 Use jump tables for sufficiently large switch statements
1420 fkeep-inline-functions
1421 Common Report Var(flag_keep_inline_functions)
1422 Generate code for functions even if they are fully inlined
1425 Common Report Var(flag_keep_static_consts) Init(1)
1426 Emit static const variables even if they are not used
1429 Common Report Var(flag_leading_underscore) Init(-1)
1430 Give external symbols a leading underscore
1434 Does nothing. Preserved for backward compatibility.
1438 Enable link-time optimization.
1441 Common RejectNegative Joined Var(flag_lto)
1442 Link-time optimization with number of parallel jobs or jobserver.
1445 Common Var(flag_lto_partition_1to1)
1446 Partition symbols and vars at linktime based on object files they originate from
1448 flto-partition=balanced
1449 Common Var(flag_lto_partition_balanced)
1450 Partition functions and vars at linktime into approximately same sized buckets
1453 Common Var(flag_lto_partition_max)
1454 Put every symbol into separate partition
1457 Common Var(flag_lto_partition_none)
1458 Disable partioning and streaming
1460 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1461 flto-compression-level=
1462 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1463 -flto-compression-level=<number> Use zlib compression level <number> for IL
1466 Common Report Var(flag_lto_report) Init(0)
1467 Report various link-time optimization statistics
1470 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1471 Set errno after built-in math functions
1474 Common Joined RejectNegative UInteger Var(flag_max_errors)
1475 -fmax-errors=<number> Maximum number of errors to report
1478 Common Report Var(mem_report)
1479 Report on permanent memory allocation
1482 Common Report Var(mem_report_wpa)
1483 Report on permanent memory allocation in WPA only
1485 ; This will attempt to merge constant section constants, if 1 only
1486 ; string constants and constants from constant pool, if 2 also constant
1488 fmerge-all-constants
1489 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1490 Attempt to merge identical constants and constant variables
1493 Common Report Var(flag_merge_constants,1) Optimization
1494 Attempt to merge identical constants across compilation units
1496 fmerge-debug-strings
1497 Common Report Var(flag_merge_debug_strings) Init(1)
1498 Attempt to merge identical debug strings across compilation units
1501 Common RejectNegative Joined UInteger
1502 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1505 Common Report Var(flag_modulo_sched) Optimization
1506 Perform SMS based modulo scheduling before the first scheduling pass
1508 fmodulo-sched-allow-regmoves
1509 Common Report Var(flag_modulo_sched_allow_regmoves)
1510 Perform SMS based modulo scheduling with register moves allowed
1512 fmove-loop-invariants
1513 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1514 Move loop invariant computations out of loops
1517 Common Var(flag_dce) Init(1) Optimization
1518 Use the RTL dead code elimination pass
1521 Common Var(flag_dse) Init(1) Optimization
1522 Use the RTL dead store elimination pass
1524 freschedule-modulo-scheduled-loops
1525 Common Report Var(flag_resched_modulo_sched) Optimization
1526 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1528 fnon-call-exceptions
1529 Common Report Var(flag_non_call_exceptions) Optimization
1530 Support synchronous non-call exceptions
1533 Common Report Var(flag_omit_frame_pointer) Optimization
1534 When possible do not generate stack frames
1537 Common Report Var(flag_opt_info) Optimization
1538 Enable all optimization info dumps on stderr
1541 Common Joined RejectNegative Var(common_deferred_options) Defer
1542 -fopt-info[-<type>=filename] Dump compiler optimization details
1544 foptimize-register-move
1545 Common Report Var(flag_regmove) Optimization
1546 Do the full register move optimization pass
1548 foptimize-sibling-calls
1549 Common Report Var(flag_optimize_sibling_calls) Optimization
1550 Optimize sibling and tail recursive calls
1553 Common Report Var(flag_partial_inlining)
1554 Perform partial inlining
1557 Common Report Var(pre_ipa_mem_report)
1558 Report on memory allocation before interprocedural optimization
1560 fpost-ipa-mem-report
1561 Common Report Var(post_ipa_mem_report)
1562 Report on memory allocation before interprocedural optimization
1565 Common Report Var(flag_pack_struct) Optimization
1566 Pack structure members together without holes
1569 Common RejectNegative Joined UInteger Optimization
1570 -fpack-struct=<number> Set initial maximum structure member alignment
1573 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1574 Return small aggregates in memory, not registers
1577 Common Report Var(flag_peel_loops) Optimization
1578 Perform loop peeling
1581 Common Report Var(flag_no_peephole,0) Optimization
1582 Enable machine specific peephole optimizations
1585 Common Report Var(flag_peephole2) Optimization
1586 Enable an RTL peephole pass before sched2
1589 Common Report Var(flag_pic,2)
1590 Generate position-independent code if possible (large mode)
1593 Common Report Var(flag_pie,2)
1594 Generate position-independent code for executables if possible (large mode)
1597 Common Report Var(flag_pic,1)
1598 Generate position-independent code if possible (small mode)
1601 Common Report Var(flag_pie,1)
1602 Generate position-independent code for executables if possible (small mode)
1605 Common Joined RejectNegative Var(common_deferred_options) Defer
1606 Specify a plugin to load
1609 Common Joined RejectNegative Var(common_deferred_options) Defer
1610 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1612 fpredictive-commoning
1613 Common Report Var(flag_predictive_commoning) Optimization
1614 Run predictive commoning optimization.
1616 fprefetch-loop-arrays
1617 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1618 Generate prefetch instructions, if available, for arrays in loops
1621 Common Report Var(profile_flag)
1622 Enable basic program profiling code
1625 Common Report Var(profile_arc_flag)
1626 Insert arc-based program profiling code
1629 Common Joined RejectNegative Var(profile_data_prefix)
1630 Set the top-level directory for storing the profile data.
1631 The default is 'pwd'.
1634 Common Report Var(flag_profile_correction)
1635 Enable correction of flow inconsistent profile data input
1639 Enable common options for generating profile info for profile feedback directed optimizations
1642 Common Joined RejectNegative
1643 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1646 Common Var(flag_profile_use)
1647 Enable common options for performing profile feedback directed optimizations
1650 Common Joined RejectNegative
1651 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1654 Common Report Var(flag_profile_values)
1655 Insert code to profile values of expressions
1658 Common Report Var(profile_report)
1659 Report on consistency of profile
1662 Common Var(common_deferred_options) Defer
1665 Common Joined RejectNegative Var(common_deferred_options) Defer
1666 -frandom-seed=<string> Make compile reproducible using <string>
1668 ; This switch causes the command line that was used to create an
1669 ; object file to be recorded into the object file. The exact format
1670 ; of this recording is target and binary file format dependent.
1671 ; It is related to the -fverbose-asm switch, but that switch only
1672 ; records information in the assembler output file as comments, so
1673 ; they never reach the object file.
1674 frecord-gcc-switches
1675 Common Report Var(flag_record_gcc_switches)
1676 Record gcc command line switches in the object file.
1679 Common Report Var(flag_pcc_struct_return,0) Optimization
1680 Return small aggregates in registers
1683 Common Report Var(flag_regmove) Optimization
1684 Enables a register move optimization
1687 Common Report Var(flag_rename_registers) Init(2) Optimization
1688 Perform a register renaming optimization pass
1691 Common Report Var(flag_reorder_blocks) Optimization
1692 Reorder basic blocks to improve code placement
1694 freorder-blocks-and-partition
1695 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1696 Reorder basic blocks and partition into hot and cold sections
1699 Common Report Var(flag_reorder_functions) Optimization
1700 Reorder functions to improve code placement
1702 frerun-cse-after-loop
1703 Common Report Var(flag_rerun_cse_after_loop) Optimization
1704 Add a common subexpression elimination pass after loop optimizations
1708 Does nothing. Preserved for backward compatibility.
1711 Common Report Var(flag_rounding_math) Optimization SetByCombined
1712 Disable optimizations that assume default FP rounding behavior
1715 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1716 Enable scheduling across basic blocks
1719 Common Report Var(flag_sched_pressure) Init(0) Optimization
1720 Enable register pressure sensitive insn scheduling
1723 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1724 Allow speculative motion of non-loads
1727 Common Report Var(flag_schedule_speculative_load) Optimization
1728 Allow speculative motion of some loads
1730 fsched-spec-load-dangerous
1731 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1732 Allow speculative motion of more loads
1735 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1736 -fsched-verbose=<number> Set the verbosity level of the scheduler
1738 fsched2-use-superblocks
1739 Common Report Var(flag_sched2_use_superblocks) Optimization
1740 If scheduling post reload, do superblock scheduling
1744 Does nothing. Preserved for backward compatibility.
1747 Common Report Var(flag_schedule_insns) Optimization
1748 Reschedule instructions before register allocation
1751 Common Report Var(flag_schedule_insns_after_reload) Optimization
1752 Reschedule instructions after register allocation
1754 ; This flag should be on when a target implements non-trivial
1755 ; scheduling hooks, maybe saving some information for its own sake.
1756 ; On IA64, for example, this is used for correct bundling.
1757 fselective-scheduling
1758 Common Report Var(flag_selective_scheduling) Optimization
1759 Schedule instructions using selective scheduling algorithm
1761 fselective-scheduling2
1762 Common Report Var(flag_selective_scheduling2) Optimization
1763 Run selective scheduling after reload
1765 fsel-sched-pipelining
1766 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1767 Perform software pipelining of inner loops during selective scheduling
1769 fsel-sched-pipelining-outer-loops
1770 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1771 Perform software pipelining of outer loops during selective scheduling
1773 fsel-sched-reschedule-pipelined
1774 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1775 Reschedule pipelined regions without pipelining
1777 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1778 ; of stalled insns into the ready list.
1779 fsched-stalled-insns
1780 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1781 Allow premature scheduling of queued insns
1783 fsched-stalled-insns=
1784 Common RejectNegative Joined UInteger
1785 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1787 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1788 ; be examined for a dependency on a stalled insn that is candidate for
1789 ; premature removal from the queue of stalled insns into the ready list (has
1790 ; an effect only if the flag 'sched_stalled_insns' is set).
1791 fsched-stalled-insns-dep
1792 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1793 Set dependence distance checking in premature scheduling of queued insns
1795 fsched-stalled-insns-dep=
1796 Common RejectNegative Joined UInteger
1797 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1799 fsched-group-heuristic
1800 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1801 Enable the group heuristic in the scheduler
1803 fsched-critical-path-heuristic
1804 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1805 Enable the critical path heuristic in the scheduler
1807 fsched-spec-insn-heuristic
1808 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1809 Enable the speculative instruction heuristic in the scheduler
1811 fsched-rank-heuristic
1812 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1813 Enable the rank heuristic in the scheduler
1815 fsched-last-insn-heuristic
1816 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1817 Enable the last instruction heuristic in the scheduler
1819 fsched-dep-count-heuristic
1820 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1821 Enable the dependent count heuristic in the scheduler
1824 Common Report Var(flag_section_anchors) Optimization
1825 Access data in the same section from shared anchor points
1829 Does nothing. Preserved for backward compatibility.
1833 Does nothing. Preserved for backward compatibility.
1836 Common Report Var(flag_ree) Init(0)
1837 Turn on Redundant Extensions Elimination pass.
1840 Common Report Var(flag_show_column) Init(1)
1841 Show column numbers in diagnostics, when available. Default on
1844 Common Report Var(flag_shrink_wrap) Optimization
1845 Emit function prologues only before parts of the function that need it,
1846 rather than at the top of the function.
1849 Common Report Var(flag_signaling_nans) Optimization SetByCombined
1850 Disable optimizations observable by IEEE signaling NaNs
1853 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
1854 Disable floating point optimizations that ignore the IEEE signedness of zero
1856 fsingle-precision-constant
1857 Common Report Var(flag_single_precision_constant) Optimization
1858 Convert floating point constants to single precision constants
1860 fsplit-ivs-in-unroller
1861 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1862 Split lifetimes of induction variables when loops are unrolled
1865 Common Report Var(flag_split_stack) Init(-1)
1866 Generate discontiguous stack frames
1869 Common Report Var(flag_split_wide_types) Optimization
1870 Split wide types into independent registers
1872 fvariable-expansion-in-unroller
1873 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1874 Apply variable expansion when loops are unrolled
1877 Common Report RejectNegative Joined
1878 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1881 Common Alias(fstack-check=, specific, no)
1882 Insert stack checking code into the program. Same as -fstack-check=specific
1885 Common Var(common_deferred_options) Defer
1887 fstack-limit-register=
1888 Common RejectNegative Joined Var(common_deferred_options) Defer
1889 -fstack-limit-register=<register> Trap if the stack goes past <register>
1891 fstack-limit-symbol=
1892 Common RejectNegative Joined Var(common_deferred_options) Defer
1893 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1896 Common Report Var(flag_stack_protect, 1)
1897 Use propolice as a stack protection method
1899 fstack-protector-all
1900 Common Report RejectNegative Var(flag_stack_protect, 2)
1901 Use a stack protection method for every function
1904 Common RejectNegative Var(flag_stack_usage)
1905 Output stack usage information on a per-function basis
1909 Does nothing. Preserved for backward compatibility.
1911 ; Nonzero if we should do (language-dependent) alias analysis.
1912 ; Typically, this analysis will assume that expressions of certain
1913 ; types do not alias expressions of certain other types. Only used
1914 ; if alias analysis (in general) is enabled.
1916 Common Report Var(flag_strict_aliasing) Optimization
1917 Assume strict aliasing rules apply
1920 Common Report Var(flag_strict_overflow)
1921 Treat signed overflow as undefined
1924 Common Report Var(flag_sync_libcalls) Init(1)
1925 Implement __atomic operations via libcalls to legacy __sync functions
1928 Common Report Var(flag_syntax_only)
1929 Check for syntax errors, then stop
1932 Common Report Var(flag_test_coverage)
1933 Create data files needed by \"gcov\"
1936 Common Report Var(flag_thread_jumps) Optimization
1937 Perform jump threading optimizations
1940 Common Report Var(time_report)
1941 Report the time taken by each compiler pass
1944 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
1945 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
1948 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
1951 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
1954 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
1957 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
1960 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
1963 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1964 Reorder top level functions, variables, and asms
1967 Common Report Var(flag_tracer)
1968 Perform superblock formation via tail duplication
1970 ; Zero means that floating-point math operations cannot generate a
1971 ; (user-visible) trap. This is the case, for example, in nonstop
1972 ; IEEE 754 arithmetic.
1974 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
1975 Assume floating-point operations can trap
1978 Common Report Var(flag_trapv) Optimization
1979 Trap for signed overflow in addition, subtraction and multiplication
1982 Common Report Var(flag_tree_ccp) Optimization
1983 Enable SSA-CCP optimization on trees
1986 Common Report Var(flag_tree_bit_ccp) Optimization
1987 Enable SSA-BIT-CCP optimization on trees
1991 Does nothing. Preserved for backward compatibility.
1994 Common Report Var(flag_tree_ch) Optimization
1995 Enable loop header copying on trees
1997 ftree-coalesce-inlined-vars
1998 Common Report Var(flag_ssa_coalesce_vars,1) Init(2) RejectNegative Optimization
1999 Enable coalescing of copy-related user variables that are inlined
2002 Common Report Var(flag_ssa_coalesce_vars,2) Optimization
2003 Enable coalescing of all copy-related user variables
2006 Common Report Var(flag_tree_copyrename) Optimization
2007 Replace SSA temporaries with better names in copies
2010 Common Report Var(flag_tree_copy_prop) Optimization
2011 Enable copy propagation on trees
2013 ftree-store-copy-prop
2015 Does nothing. Preserved for backward compatibility.
2018 Common Report Var(flag_tree_cselim) Init(2) Optimization
2019 Transform condition stores into unconditional ones
2021 ftree-switch-conversion
2022 Common Report Var(flag_tree_switch_conversion) Optimization
2023 Perform conversions of switch initializations.
2026 Common Report Var(flag_tree_dce) Optimization
2027 Enable SSA dead code elimination optimization on trees
2029 ftree-dominator-opts
2030 Common Report Var(flag_tree_dom) Optimization
2031 Enable dominator optimizations
2034 Common Report Var(flag_tree_tail_merge) Optimization
2035 Enable tail merging on trees
2038 Common Report Var(flag_tree_dse) Optimization
2039 Enable dead store elimination
2042 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2043 Enable forward propagation on trees
2046 Common Report Var(flag_tree_fre) Optimization
2047 Enable Full Redundancy Elimination (FRE) on trees
2050 Common Report Var(flag_optimize_strlen) Optimization
2051 Enable string length optimizations on trees
2053 ftree-loop-distribution
2054 Common Report Var(flag_tree_loop_distribution) Optimization
2055 Enable loop distribution on trees
2057 ftree-loop-distribute-patterns
2058 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2059 Enable loop distribution for patterns transformed into a library call
2062 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2063 Enable loop invariant motion on trees
2066 Common Alias(floop-interchange)
2067 Enable loop interchange transforms. Same as -floop-interchange
2070 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2071 Create canonical induction variables in loops
2074 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2075 Enable loop optimizations on tree level
2077 ftree-parallelize-loops=
2078 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
2079 Enable automatic parallelization of loops
2082 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2083 Enable hoisting loads from conditional pointers.
2086 Common Report Var(flag_tree_pre) Optimization
2087 Enable SSA-PRE optimization on trees
2090 Common Report Var(flag_tree_partial_pre) Optimization
2091 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination
2094 Common Report Var(flag_tree_pta) Init(1) Optimization
2095 Perform function-local points-to analysis on trees.
2098 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2099 Enable reassociation on tree level
2103 Does nothing. Preserved for backward compatibility.
2106 Common Report Var(flag_tree_sink) Optimization
2107 Enable SSA code sinking on trees
2110 Common Report Var(flag_tree_slsr) Optimization
2111 Perform straight-line strength reduction
2114 Common Report Var(flag_tree_sra) Optimization
2115 Perform scalar replacement of aggregates
2118 Common Report Var(flag_tree_ter) Optimization
2119 Replace temporary expressions in the SSA->normal pass
2122 Common Report Var(flag_tree_live_range_split) Optimization
2123 Perform live range splitting during the SSA->normal pass
2126 Common Report Var(flag_tree_vrp) Init(0) Optimization
2127 Perform Value Range Propagation on trees
2130 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
2131 Compile whole compilation unit at a time
2134 Common Report Var(flag_unroll_loops) Optimization
2135 Perform loop unrolling when iteration count is known
2138 Common Report Var(flag_unroll_all_loops) Optimization
2139 Perform loop unrolling for all loops
2141 ; Nonzero means that loop optimizer may assume that the induction variables
2142 ; that control loops do not overflow and that the loops with nontrivial
2143 ; exit condition are not infinite
2144 funsafe-loop-optimizations
2145 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2146 Allow loop optimizations to assume that the loops behave in normal way
2149 Common Report Var(flag_associative_math) SetByCombined
2150 Allow optimization for floating-point arithmetic which may change the
2151 result of the operation due to rounding.
2154 Common Report Var(flag_reciprocal_math) SetByCombined
2155 Same as -fassociative-math for expressions which include division.
2157 ; Nonzero means that unsafe floating-point math optimizations are allowed
2158 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2159 ; are allowed to assume that their arguments and results are "normal"
2160 ; (e.g., nonnegative for SQRT).
2161 funsafe-math-optimizations
2162 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2163 Allow math optimizations that may violate IEEE or ISO standards
2166 Common Report Var(flag_unswitch_loops) Optimization
2167 Perform loop unswitching
2170 Common Report Var(flag_unwind_tables) Optimization
2171 Just generate unwind tables for exception handling
2176 ; Positive if we should track variables, negative if we should run
2177 ; the var-tracking pass only to discard debug annotations, zero if
2178 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2179 ; will be set according to optimize, debug_info_level and debug_hooks
2180 ; in process_options ().
2182 Common Report Var(flag_var_tracking) Init(2) Optimization
2183 Perform variable tracking
2185 ; Positive if we should track variables at assignments, negative if
2186 ; we should run the var-tracking pass only to discard debug
2187 ; annotations. When flag_var_tracking_assignments ==
2188 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2189 fvar-tracking-assignments
2190 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2191 Perform variable tracking by annotating assignments
2193 ; Nonzero if we should toggle flag_var_tracking_assignments after
2194 ; processing options and computing its default. */
2195 fvar-tracking-assignments-toggle
2196 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2197 Toggle -fvar-tracking-assignments
2199 fvar-tracking-uninit
2200 Common Report Var(flag_var_tracking_uninit) Optimization
2201 Perform variable tracking and also tag variables that are uninitialized
2204 Common Report Var(flag_tree_vectorize) Optimization
2205 Enable loop vectorization on trees
2207 ftree-vectorizer-verbose=
2208 Common RejectNegative Joined UInteger Var(common_deferred_options) Defer
2209 -ftree-vectorizer-verbose=<number> This switch is deprecated. Use -fopt-info instead.
2212 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2213 Enable basic block vectorization (SLP) on trees
2216 Common Report Var(flag_vect_cost_model) Optimization
2217 Enable use of cost model in vectorization
2219 ftree-vect-loop-version
2220 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2221 Enable loop versioning when doing loop vectorization on trees
2224 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2225 Enable copy propagation of scalar-evolution information.
2227 ; -fverbose-asm causes extra commentary information to be produced in
2228 ; the generated assembly code (to make it more readable). This option
2229 ; is generally only of use to those who actually need to read the
2230 ; generated assembly code (perhaps while debugging the compiler itself).
2231 ; -fno-verbose-asm, the default, causes the extra information
2232 ; to not be added and is useful when comparing two assembler files.
2234 Common Report Var(flag_verbose_asm)
2235 Add extra commentary to assembler output
2238 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2239 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2242 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2245 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2248 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2251 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2254 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2257 Common Report Var(flag_value_profile_transformations) Optimization
2258 Use expression value profiles in optimizations
2261 Common Report Var(flag_web) Init(2) Optimization
2262 Construct webs and split unrelated uses of single variable
2264 ftree-builtin-call-dce
2265 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2266 Enable conditional dead code elimination for builtin calls
2269 Common Report Var(flag_whole_program) Init(0) Optimization
2270 Perform whole program optimizations
2273 Common Report Var(flag_wrapv) Optimization
2274 Assume signed arithmetic overflow wraps around
2276 fzero-initialized-in-bss
2277 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2278 Put zero initialized data in the bss section
2281 Common JoinedOrMissing
2282 Generate debug information in default format
2285 Common JoinedOrMissing Negative(gdwarf-)
2286 Generate debug information in COFF format
2289 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2290 Generate debug information in DWARF v2 (or later) format
2293 Common JoinedOrMissing
2294 Generate debug information in default extended format
2297 Common RejectNegative Var(debug_generate_pub_sections, 0) Init(-1)
2298 Don't generate DWARF pubnames and pubtypes sections.
2301 Common RejectNegative Var(debug_generate_pub_sections, 1)
2302 Generate DWARF pubnames and pubtypes sections.
2304 gno-record-gcc-switches
2305 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2306 Don't record gcc command line switches in DWARF DW_AT_producer.
2308 grecord-gcc-switches
2309 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2310 Record gcc command line switches in DWARF DW_AT_producer.
2313 Common JoinedOrMissing Negative(gstabs+)
2314 Generate debug information in STABS format
2317 Common JoinedOrMissing Negative(gvms)
2318 Generate debug information in extended STABS format
2321 Common RejectNegative Var(dwarf_strict,0) Init(0)
2322 Emit DWARF additions beyond selected version
2325 Common Report RejectNegative Var(dwarf_strict,1)
2326 Don't emit DWARF additions beyond selected version
2329 Common Report Var(flag_gtoggle)
2330 Toggle debug information generation
2333 Common JoinedOrMissing Negative(gxcoff)
2334 Generate debug information in VMS format
2337 Common JoinedOrMissing Negative(gxcoff+)
2338 Generate debug information in XCOFF format
2341 Common JoinedOrMissing Negative(gcoff)
2342 Generate debug information in extended XCOFF format
2345 Driver Joined Separate
2348 Common Joined Var(plugindir_string) Init(0)
2349 -iplugindir=<dir> Set <dir> to be the default plugin directory
2352 Driver Joined Separate
2357 no-canonical-prefixes
2370 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2371 -o <file> Place output into <file>
2374 Common Var(profile_flag)
2375 Enable function profiling
2378 Driver Var(pass_exit_codes)
2381 Common Alias(Wpedantic)
2384 Common Var(flag_pedantic_errors)
2385 Like -pedantic but issue them as errors
2391 Driver Var(use_pipes)
2394 Driver JoinedOrMissing Var(print_file_name)
2396 print-libgcc-file-name
2399 print-multi-directory
2400 Driver Var(print_multi_directory)
2403 Driver Var(print_multi_lib)
2405 print-multi-os-directory
2406 Driver Var(print_multi_os_directory)
2409 Driver JoinedOrMissing Var(print_prog_name)
2412 Driver Var(print_search_dirs)
2415 Driver Var(print_sysroot)
2417 print-sysroot-headers-suffix
2418 Driver Var(print_sysroot_headers_suffix)
2421 Common Var(quiet_flag) RejectDriver
2422 Do not display functions compiled or elapsed time
2440 Driver Var(report_times)
2443 Driver JoinedOrMissing
2446 Driver Joined Separate
2450 ; C option, but driver must not handle as "-u ndef".
2453 Common Driver Var(verbose_flag)
2454 Enable verbose output
2457 Common Var(version_flag) RejectDriver
2458 Display the compiler's version
2461 Common Var(inhibit_warnings)
2465 Driver Separate Var(wrapper_string)
2468 Driver Joined Separate
2471 Driver RejectNegative Negative(pie)
2472 Create a shared library
2478 Driver Separate Alias(specs=)
2491 ; Documented for Fortran, but always accepted by driver.
2498 ; Documented for Go, but always accepted by driver.
2504 Driver RejectNegative Negative(shared)
2505 Create a position independent executable
2508 Driver Joined Separate
2510 ; This comment is to ensure we retain the blank line above.