1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003-2016 Free Software Foundation, Inc.
5 ; This file is part of GCC.
7 ; GCC is free software; you can redistribute it and/or modify it under
8 ; the terms of the GNU General Public License as published by the Free
9 ; Software Foundation; either version 3, or (at your option) any later
12 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 ; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 ; You should have received a copy of the GNU General Public License
18 ; along with GCC; see the file COPYING3. If not see
19 ; <http://www.gnu.org/licenses/>.
21 ; See the GCC internals manual (options.texi) for a description of this file's format.
23 ; Please try to keep this file in ASCII collating order.
37 ; Not used directly to control optimizations, only to save -Ofast
38 ; setting for "optimize" attributes.
42 ; True if this is the lto front end. This is used to disable gimple
43 ; generation and lowering passes that are normally run on the output
44 ; of a front end. These passes must be bypassed for lto since they
45 ; have already been done before the gimple was written.
49 ; This variable is set to non-0 only by LTO front-end. 1 indicates that
50 ; the output produced will be used for incrmeental linking (thus weak symbols
51 ; can still be bound).
53 int flag_incremental_link = 0
55 ; 0 means straightforward implementation of complex divide acceptable.
56 ; 1 means wide ranges of inputs must work for complex divide.
57 ; 2 means C99-like requirements for complex multiply and divide.
59 int flag_complex_method = 1
61 ; Nonzero if subexpressions must be evaluated from left-to-right.
63 int flag_evaluation_order = 0
65 ; Language specific warning pass for unused results.
67 bool flag_warn_unused_result = false
72 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
76 ; Nonzero if we should write GIMPLE bytecode for offload compilation.
78 int flag_generate_offload = 0
80 ; True to warn about any objects definitions whose size is larger
81 ; than N bytes. Also want about function definitions whose returned
82 ; values are larger than N bytes, where N is 'larger_than_size'.
87 HOST_WIDE_INT larger_than_size
89 ; True to warn about any function whose frame size is larger
92 bool warn_frame_larger_than
95 HOST_WIDE_INT frame_larger_than_size
97 ; Nonzero means we should be saving declaration info into a .X file.
99 int flag_gen_aux_info = 0
101 ; Nonzero if we are compiling code for a shared library, zero for
106 ; These two are really VEC(char_p,heap) *.
109 void *flag_instrument_functions_exclude_functions
112 void *flag_instrument_functions_exclude_files
114 ; Generic structs (e.g. templates not explicitly specialized)
115 ; may not have a compilation unit associated with them, and so
116 ; may need to be treated differently from ordinary structs.
118 ; Structs only handled by reference (indirectly), will also usually
119 ; not need as much debugging information.
122 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
125 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
127 ; True if we should exit after parsing options.
129 bool exit_after_options
131 ; Type(s) of debugging information we are producing (if any). See
132 ; flag-types.h for the definitions of the different possible types of
133 ; debugging information.
135 enum debug_info_type write_symbols = NO_DEBUG
137 ; Level of debugging information we are producing. See flag-types.h
138 ; for the definitions of the different possible levels.
140 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
142 ; Nonzero means use GNU-only extensions in the generated symbolic
143 ; debugging information. Currently, this only has an effect when
144 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
146 bool use_gnu_debug_info_extensions
148 ; Original value of maximum field alignment in bytes, specified via
149 ; -fpack-struct=<value>.
151 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
153 ; Type of stack check.
155 enum stack_check_type flag_stack_check = NO_STACK_CHECK
157 ; True if stack usage information needs to be computed.
159 bool flag_stack_usage_info = false
161 ; -dA causes debug commentary information to be produced in
162 ; the generated assembly code (to make it more readable). This option
163 ; is generally only of use to those who actually need to read the
164 ; generated assembly code (perhaps while debugging the compiler itself).
165 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
166 ; to be a catchall for printing debug information in the assembler file.
171 ; Balance between GNAT encodings and standard DWARF to emit.
173 enum dwarf_gnat_encodings gnat_encodings = DWARF_GNAT_ENCODINGS_DEFAULT
175 ; -dP causes the rtl to be emitted as a comment in assembly.
177 int flag_dump_rtl_in_asm
179 ; Whether -da was passed (used only in handle_common_deferred_options).
181 bool flag_dump_all_passed
183 ; Other flags saying which kinds of debugging dump have been requested.
186 int rtl_dump_and_exit
189 int flag_print_asm_name
191 ; Name of top-level original source file (what was input to cpp).
192 ; This comes from the #-command at the beginning of the actual input.
193 ; If there isn't any there, then this is the cc1 input file name.
195 const char *main_input_filename
197 ; Pointer to base name in main_input_filename, with directories and a
198 ; single final extension removed, and the length of this base
202 const char *main_input_basename
205 int main_input_baselength
207 ; Which options have been printed by --help.
211 ; Which enums have been printed by --help. 0 = not printed, no
212 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
215 char *help_enum_printed
217 ; The number of columns for --help output.
219 unsigned int help_columns
221 ; Whether this options structure has been through finish_options
223 bool flag_opts_finished
225 ; What the sanitizer should instrument
227 unsigned int flag_sanitize
229 ; What sanitizers should recover from errors
231 unsigned int flag_sanitize_recover = SANITIZE_UNDEFINED | SANITIZE_NONDEFAULT | SANITIZE_KERNEL_ADDRESS
233 fsanitize-coverage=trace-pc
234 Common Report Var(flag_sanitize_coverage)
235 Enable coverage-guided fuzzing code instrumentation.
236 Inserts call to __sanitizer_cov_trace_pc into every basic block.
238 ; Flag whether a prefix has been added to dump_base_name
240 bool dump_base_name_prefixed = false
242 ; Flag whether HSA generation has been explicitely disabled
244 bool flag_disable_hsa = false
256 Driver Alias(coverage)
262 Common Separate Alias(d)
265 Common Joined Alias(d)
268 Common Separate Alias(dumpbase)
271 Common Separate Alias(dumpdir)
274 Driver Separate Alias(e)
277 Driver Joined Alias(e)
280 Common Warning Alias(Wextra)
283 Driver Separate Alias(Xassembler)
286 Driver JoinedOrMissing Alias(Xassembler)
289 Driver Separate Alias(Xlinker)
292 Driver JoinedOrMissing Alias(Xlinker)
295 Driver Separate Alias(u)
298 Driver Joined Alias(u)
301 Common Driver Var(help_flag)
302 Display this information.
305 Common Driver Report Joined
306 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params.
309 Driver Separate Alias(x)
312 Driver Joined Alias(x)
315 Driver Separate Alias(L)
318 Driver Joined Alias(L)
320 -no-canonical-prefixes
321 Driver Alias(no-canonical-prefixes)
323 -no-standard-libraries
324 Driver Alias(nostdlib)
327 Driver Var(no_sysroot_suffix)
336 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
339 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
342 Driver Alias(pass-exit-codes)
345 Common Alias(Wpedantic)
348 Common Alias(pedantic-errors)
357 Driver Separate Alias(B)
360 Driver JoinedOrMissing Alias(B)
366 Driver Separate Alias(print-file-name=)
369 Driver JoinedOrMissing Alias(print-file-name=)
371 -print-libgcc-file-name
372 Driver Alias(print-libgcc-file-name)
374 -print-multi-directory
375 Driver Alias(print-multi-directory)
378 Driver Alias(print-multi-lib)
380 -print-multi-os-directory
381 Driver Alias(print-multi-os-directory)
384 Driver Alias(print-multiarch)
387 Driver Separate Alias(print-prog-name=)
390 Driver JoinedOrMissing Alias(print-prog-name=)
393 Driver Alias(print-search-dirs)
396 Driver Alias(print-sysroot)
398 -print-sysroot-headers-suffix
399 Driver Alias(print-sysroot-headers-suffix)
405 Driver Alias(save-temps)
411 Driver Separate Alias(specs=)
414 Driver Joined Alias(specs=)
420 Driver Alias(symbolic)
424 Alias for --help=target.
432 ;; The driver used to convert options such as --help into forms such
433 ;; as -fhelp; the following four entries are for compatibility with
434 ;; any direct uses of those (undocumented) -f forms
436 Common Driver Alias(-help)
439 Common Driver Joined Alias(-help=)
442 Common Driver Alias(-target-help)
445 Common Driver Alias(-version)
449 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters.
452 Common Joined Alias(-param)
455 Driver Separate Alias(-sysroot=)
458 Driver JoinedOrMissing
464 Driver Joined Separate
470 Driver Joined Separate
476 Common JoinedOrMissing Optimization
477 -O<number> Set optimization level to <number>.
481 Optimize for space rather than speed.
485 Optimize for speed disregarding exact standards compliance.
489 Optimize for debugging experience rather than speed or size.
501 Driver Joined Separate
507 Driver Joined Separate
528 Common RejectNegative Warning Alias(Wextra)
529 This switch is deprecated; use -Wextra instead.
532 Driver JoinedOrMissing
535 Driver JoinedOrMissing
538 Driver JoinedOrMissing
541 Common Var(warn_aggregate_return) Warning
542 Warn about returning structures, unions or arrays.
544 Waggressive-loop-optimizations
545 Common Var(warn_aggressive_loop_optimizations) Init(1) Warning
546 Warn if a loop with constant number of iterations triggers undefined behavior.
549 Common Var(warn_array_bounds) Warning
550 Warn if an array is accessed out of bounds.
553 Common Joined RejectNegative UInteger Var(warn_array_bounds) Warning
554 Warn if an array is accessed out of bounds.
557 Common Var(warn_attributes) Init(1) Warning
558 Warn about inappropriate attribute usage.
561 Common Var(warn_cast_align) Warning
562 Warn about pointer casts which increase alignment.
565 Common Var(warn_cpp) Init(1) Warning
566 Warn when a #warning directive is encountered.
568 Wdeprecated-declarations
569 Common Var(warn_deprecated_decl) Init(1) Warning
570 Warn about uses of __attribute__((deprecated)) declarations.
572 Wdisabled-optimization
573 Common Var(warn_disabled_optimization) Warning
574 Warn when an optimization pass is disabled.
577 Common Var(warnings_are_errors)
578 Treat all warnings as errors.
582 Treat specified warning as error.
585 Common Var(extra_warnings) Warning
586 Print extra (possibly unwanted) warnings.
589 Common Var(flag_fatal_errors)
590 Exit on the first error occurred.
593 Common RejectNegative Joined UInteger Warning
594 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes.
597 Common Var(warn_free_nonheap_object) Init(1) Warning
598 Warn when attempting to free a non-heap object.
601 Common Var(warn_hsa) Init(1) Warning
602 Warn when a function cannot be expanded to HSAIL.
605 Common Var(warn_inline) Warning
606 Warn when an inlined function cannot be inlined.
608 Winvalid-memory-model
609 Common Var(warn_invalid_memory_model) Init(1) Warning
610 Warn when an atomic memory model parameter is known to be outside the valid range.
613 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
616 Common RejectNegative Joined UInteger Warning
617 -Wlarger-than=<number> Warn if an object is larger than <number> bytes.
620 Common Var(warn_null_dereference) Warning
621 Warn if dereferencing a NULL pointer may lead to erroneous or undefined behavior.
623 Wunsafe-loop-optimizations
624 Common Var(warn_unsafe_loop_optimizations) Warning
625 Warn if the loop cannot be optimized due to nontrivial assumptions.
628 Common Warning Alias(Wsuggest-attribute=noreturn)
631 Common Var(warn_odr_violations) Init(1) Warning
632 Warn about some C++ One Definition Rule violations during link time optimization.
635 Common Var(warn_overflow) Init(1) Warning
636 Warn about overflow in arithmetic expressions.
639 Common Var(warn_lto_type_mismatch) Init(1) Warning
640 During link time optimization warn about mismatched types of global declarations.
643 Common Var(warn_packed) Warning
644 Warn when the packed attribute has no effect on struct layout.
647 Common Var(warn_padded) Warning
648 Warn when padding is required to align structure members.
651 Common Var(pedantic) Init(0) Warning
652 Issue warnings needed for strict compliance to the standard.
655 Common Var(warn_return_local_addr) Init(1) Warning
656 Warn about returning a pointer/reference to a local or temporary variable.
659 Common Var(warn_shadow) Warning
660 Warn when one local variable shadows another.
663 Common Var(warn_stack_protect) Warning
664 Warn when not issuing stack smashing protection for some reason.
667 Common Joined RejectNegative UInteger Var(warn_stack_usage) Init(-1) Warning
668 Warn if stack usage might be larger than specified amount.
672 Warn about code which might break strict aliasing rules.
675 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Warning
676 Warn about code which might break strict aliasing rules.
680 Warn about optimizations that assume that signed overflow is undefined.
683 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Warning
684 Warn about optimizations that assume that signed overflow is undefined.
686 Wsuggest-attribute=const
687 Common Var(warn_suggest_attribute_const) Warning
688 Warn about functions which might be candidates for __attribute__((const)).
690 Wsuggest-attribute=pure
691 Common Var(warn_suggest_attribute_pure) Warning
692 Warn about functions which might be candidates for __attribute__((pure)).
694 Wsuggest-attribute=noreturn
695 Common Var(warn_suggest_attribute_noreturn) Warning
696 Warn about functions which might be candidates for __attribute__((noreturn)).
699 Common Var(warn_suggest_final_types) Warning
700 Warn about C++ polymorphic types where adding final keyword would improve code quality.
702 Wsuggest-final-methods
703 Common Var(warn_suggest_final_methods) Warning
704 Warn about C++ virtual methods where adding final keyword would improve code quality.
707 Common Var(warn_system_headers) Warning
708 Do not suppress warnings from system headers.
711 Common Var(warn_trampolines) Warning
712 Warn whenever a trampoline is generated.
715 Common Var(warn_type_limits) Warning EnabledBy(Wextra)
716 Warn if a comparison is always true or always false due to the limited range of the data type.
719 Common Var(warn_uninitialized) Warning EnabledBy(Wextra)
720 Warn about uninitialized automatic variables.
723 Common Var(warn_maybe_uninitialized) Warning EnabledBy(Wuninitialized)
724 Warn about maybe uninitialized automatic variables.
728 Does nothing. Preserved for backward compatibility.
731 Common Var(warn_unused) Init(0) Warning
732 Enable all -Wunused- warnings.
734 Wunused-but-set-parameter
735 Common Var(warn_unused_but_set_parameter) Warning EnabledBy(Wunused && Wextra)
736 Warn when a function parameter is only set, otherwise unused.
738 Wunused-but-set-variable
739 Common Var(warn_unused_but_set_variable) Warning EnabledBy(Wunused)
740 Warn when a variable is only set, otherwise unused.
743 Common Var(warn_unused_function) Warning EnabledBy(Wunused)
744 Warn when a function is unused.
747 Common Var(warn_unused_label) Warning EnabledBy(Wunused)
748 Warn when a label is unused.
751 Common Var(warn_unused_parameter) Warning EnabledBy(Wunused && Wextra)
752 Warn when a function parameter is unused.
755 Common Var(warn_unused_value) Warning EnabledBy(Wunused)
756 Warn when an expression value is unused.
759 Common Var(warn_unused_variable) Warning EnabledBy(Wunused)
760 Warn when a variable is unused.
763 Common Var(warn_coverage_mismatch) Init(1) Warning
764 Warn in case profiles in -fprofile-use do not match.
766 Wvector-operation-performance
767 Common Var(warn_vector_operation_performance) Warning
768 Warn when a vector operation is compiled outside the SIMD.
783 Common Separate Var(aux_info_file_name)
784 -aux-info <file> Emit declaration information into <file>.
787 Common Joined Alias(aux-info)
790 Common Separate RejectDriver Var(aux_base_name)
793 Common Separate RejectDriver
803 -d<letters> Enable dumps from specific passes of the compiler.
806 Common Separate Var(dump_base_name)
807 -dumpbase <file> Set the file basename to be used for dumps.
810 Common Separate Var(dump_dir_name)
811 -dumpdir <dir> Set the directory name to be used for dumps.
823 Driver Joined Separate
825 ; This option has historically been passed down to the linker by an
826 ; accident of a %{e*} spec, so ensure it continues to be passed down
827 ; as a single option. The supported option for this purpose is
828 ; -rdynamic. See PR 47390.
832 ; The version of the C++ ABI in use. The following values are allowed:
834 ; 0: The version of the ABI believed most conformant with the C++ ABI
835 ; specification. This ABI may change as bugs are discovered and fixed.
836 ; Therefore, 0 will not necessarily indicate the same ABI in different
839 ; 1: The version of the ABI first used in G++ 3.2. No longer selectable.
841 ; 2: The version of the ABI first used in G++ 3.4, and the default
844 ; 3: The version of the ABI that fixes the missing underscore
845 ; in template non-type arguments of pointer type.
847 ; 4: The version of the ABI that introduces unambiguous mangling of
848 ; vector types. First selectable in G++ 4.5.
850 ; 5: The version of the ABI that ignores attribute const/noreturn
851 ; in function pointer mangling, and corrects mangling of decltype and
852 ; function parameters used in other parameters and the return type.
853 ; First selectable in G++ 4.6.
855 ; 6: The version of the ABI that doesn't promote scoped enums to int and
856 ; changes the mangling of template argument packs, const/static_cast,
857 ; prefix ++ and --, and a class scope function used as a template
859 ; First selectable in G++ 4.7.
861 ; 7: The version of the ABI that treats nullptr_t as a builtin type and
862 ; corrects the mangling of lambdas in default argument scope.
863 ; First selectable in G++ 4.8.
865 ; 8: The version of the ABI that corrects the substitution behavior of
866 ; function types with function-cv-qualifiers.
867 ; First selectable in G++ 4.9 and default in G++ 5.
869 ; 9: The version of the ABI that corrects the alignment of nullptr_t.
870 ; First selectable and default in G++ 5.2.
872 ; 10: The version of the ABI that mangles attributes that affect type
873 ; identity, such as ia32 calling convention attributes (stdcall, etc.)
874 ; Default in G++ 6 (set in c_common_post_options).
876 ; Additional positive integers will be assigned as new versions of
877 ; the ABI become the default version of the ABI.
879 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(0)
880 The version of the C++ ABI in use.
882 faggressive-loop-optimizations
883 Common Report Var(flag_aggressive_loop_optimizations) Optimization Init(1)
884 Aggressively optimize loops using language constraints.
887 Common Report Var(align_functions,0) Optimization UInteger
888 Align the start of functions.
891 Common RejectNegative Joined UInteger Var(align_functions)
894 Common Report Var(align_jumps,0) Optimization UInteger
895 Align labels which are only reached by jumping.
898 Common RejectNegative Joined UInteger Var(align_jumps)
901 Common Report Var(align_labels,0) Optimization UInteger
905 Common RejectNegative Joined UInteger Var(align_labels)
908 Common Report Var(align_loops,0) Optimization UInteger
909 Align the start of loops.
912 Common RejectNegative Joined UInteger Var(align_loops)
916 Does nothing. Preserved for backward compatibility.
920 Does nothing. Preserved for backward compatibility.
922 fargument-noalias-global
924 Does nothing. Preserved for backward compatibility.
926 fargument-noalias-anything
928 Does nothing. Preserved for backward compatibility.
931 Common Driver Report Joined
932 Select what to sanitize.
935 Common Joined RejectNegative Var(common_deferred_options) Defer
936 -fasan-shadow-offset=<number> Use custom shadow memory offset.
939 Common Joined RejectNegative Var(common_deferred_options) Defer
940 -fsanitize-sections=<sec1,sec2,...> Sanitize global variables
941 in user-defined sections.
945 After diagnosing undefined behavior attempt to continue execution.
949 This switch is deprecated; use -fsanitize-recover= instead.
951 fsanitize-undefined-trap-on-error
952 Common Driver Report Var(flag_sanitize_undefined_trap_on_error) Init(0)
953 Use trap instead of a library function for undefined behavior sanitization.
955 fasynchronous-unwind-tables
956 Common Report Var(flag_asynchronous_unwind_tables) Optimization
957 Generate unwind tables that are exact at each instruction boundary.
960 Common Report Var(flag_auto_inc_dec) Init(1) Optimization
961 Generate auto-inc/dec instructions.
964 Common Report Var(flag_auto_profile)
965 Use sample profile information for call graph node weights. The default
966 profile file is fbdata.afdo in 'pwd'.
969 Common Joined RejectNegative Var(auto_profile_file)
970 Use sample profile information for call graph node weights. The profile
971 file is specified in the argument.
973 ; -fcheck-bounds causes gcc to generate array bounds checks.
974 ; For C, C++ and ObjC: defaults off.
975 ; For Java: defaults to on.
976 ; For Fortran: defaults to off.
978 Common Report Var(flag_bounds_check)
979 Generate code to check bounds before indexing arrays.
982 Common Report Var(flag_branch_on_count_reg) Optimization
983 Replace add, compare, branch with branch on count register.
985 fbranch-probabilities
986 Common Report Var(flag_branch_probabilities) Optimization
987 Use profiling information for branch probabilities.
989 fbranch-target-load-optimize
990 Common Report Var(flag_branch_target_load_optimize) Optimization
991 Perform branch target load optimization before prologue / epilogue threading.
993 fbranch-target-load-optimize2
994 Common Report Var(flag_branch_target_load_optimize2) Optimization
995 Perform branch target load optimization after prologue / epilogue threading.
998 Common Report Var(flag_btr_bb_exclusive) Optimization
999 Restrict target load migration not to re-use registers in any basic block.
1002 Common Joined RejectNegative Var(common_deferred_options) Defer
1003 -fcall-saved-<register> Mark <register> as being preserved across functions.
1006 Common Joined RejectNegative Var(common_deferred_options) Defer
1007 -fcall-used-<register> Mark <register> as being corrupted by function calls.
1009 ; Nonzero for -fcaller-saves: allocate values in regs that need to
1010 ; be saved across function calls, if that produces overall better code.
1011 ; Optional now, so people can test it.
1013 Common Report Var(flag_caller_saves) Optimization
1014 Save registers around function calls.
1017 Common Report Var(flag_check_data_deps)
1018 This switch is deprecated; do not use.
1021 Common Var(flag_check_new)
1022 Check the return value of new in C++.
1025 Common Var(flag_checking) Init(CHECKING_P)
1026 Perform internal consistency checkings.
1028 fcombine-stack-adjustments
1029 Common Report Var(flag_combine_stack_adjustments) Optimization
1030 Looks for opportunities to reduce stack adjustments and stack references.
1033 Common Report Var(flag_no_common,0)
1034 Do not put uninitialized globals in the common section.
1038 ; Converted by the driver to -fcompare-debug= options.
1041 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
1042 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump.
1044 fcompare-debug-second
1045 Common Driver RejectNegative Var(flag_compare_debug)
1046 Run only the second compilation of -fcompare-debug.
1049 Common Report Var(flag_compare_elim_after_reload) Optimization
1050 Perform comparison elimination after register allocation has finished.
1053 Common Var(flag_conserve_stack) Optimization
1054 Do not perform optimizations increasing noticeably stack usage.
1057 Common Report Var(flag_cprop_registers) Optimization
1058 Perform a register copy-propagation optimization pass.
1061 Common Report Var(flag_crossjumping) Optimization
1062 Perform cross-jumping optimization.
1065 Common Report Var(flag_cse_follow_jumps) Optimization
1066 When running CSE, follow jumps to their targets.
1070 Does nothing. Preserved for backward compatibility.
1073 Common Report Var(flag_cx_limited_range) Optimization SetByCombined
1074 Omit range reduction step when performing complex division.
1077 Common Report Var(flag_cx_fortran_rules) Optimization
1078 Complex multiplication and division follow Fortran rules.
1081 Common Report Var(flag_data_sections)
1082 Place data items into their own section.
1085 Common Report Var(common_deferred_options) Defer
1086 List all available debugging counters with their limits and counts.
1089 Common RejectNegative Joined Var(common_deferred_options) Defer
1090 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
1093 Common Joined RejectNegative Var(common_deferred_options) Defer
1094 Map one directory name to another in debug information.
1096 fdebug-types-section
1097 Common Report Var(flag_debug_types_section) Init(0)
1098 Output .debug_types section when using DWARF v4 debuginfo.
1100 ; Nonzero for -fdefer-pop: don't pop args after each function call
1101 ; instead save them up to pop many calls' args with one insns.
1103 Common Report Var(flag_defer_pop) Optimization
1104 Defer popping functions args from stack until later.
1107 Common Report Var(flag_delayed_branch) Optimization
1108 Attempt to fill delay slots of branch instructions.
1110 fdelete-dead-exceptions
1111 Common Report Var(flag_delete_dead_exceptions) Init(0) Optimization
1112 Delete dead instructions that may throw exceptions.
1114 fdelete-null-pointer-checks
1115 Common Report Var(flag_delete_null_pointer_checks) Init(-1) Optimization
1116 Delete useless null pointer checks.
1118 fdevirtualize-at-ltrans
1119 Common Report Var(flag_ltrans_devirtualize)
1120 Stream extra data to support more aggressive devirtualization in LTO local transformation mode.
1122 fdevirtualize-speculatively
1123 Common Report Var(flag_devirtualize_speculatively) Optimization
1124 Perform speculative devirtualization.
1127 Common Report Var(flag_devirtualize) Optimization
1128 Try to convert virtual calls to direct ones.
1130 fdiagnostics-show-location=
1131 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
1132 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics.
1134 ; Required for these enum values.
1139 Name(diagnostic_prefixing_rule) Type(int)
1142 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
1145 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
1147 fdiagnostics-show-caret
1148 Common Var(flag_diagnostics_show_caret) Init(1)
1149 Show the source line with a caret indicating the column.
1152 Common Alias(fdiagnostics-color=,always,never)
1156 Driver Common Joined RejectNegative Var(flag_diagnostics_show_color) Enum(diagnostic_color_rule) Init(DIAGNOSTICS_COLOR_NO)
1157 -fdiagnostics-color=[never|always|auto] Colorize diagnostics.
1159 ; Required for these enum values.
1164 Name(diagnostic_color_rule) Type(int)
1167 Enum(diagnostic_color_rule) String(never) Value(DIAGNOSTICS_COLOR_NO)
1170 Enum(diagnostic_color_rule) String(always) Value(DIAGNOSTICS_COLOR_YES)
1173 Enum(diagnostic_color_rule) String(auto) Value(DIAGNOSTICS_COLOR_AUTO)
1175 fdiagnostics-show-option
1176 Common Var(flag_diagnostics_show_option) Init(1)
1177 Amend appropriate diagnostic messages with the command line option that controls them.
1180 Common Joined RejectNegative Var(common_deferred_options) Defer
1181 -fdisable-[tree|rtl|ipa]-<pass>=range1+range2 disables an optimization pass.
1184 Common Joined RejectNegative Var(common_deferred_options) Defer
1185 -fenable-[tree|rtl|ipa]-<pass>=range1+range2 enables an optimization pass.
1188 Common Joined RejectNegative Var(common_deferred_options) Defer
1189 -fdump-<type> Dump various compiler internals to a file.
1192 Driver RejectNegative
1195 Common RejectNegative Joined Var(flag_dump_final_insns)
1196 -fdump-final-insns=filename Dump to filename the insns at the end of translation.
1199 Common RejectNegative Joined Var(flag_dump_go_spec)
1200 -fdump-go-spec=filename Write all declarations to file as Go code.
1203 Common Report Var(flag_dump_noaddr)
1204 Suppress output of addresses in debugging dumps.
1207 Common Driver Var(flag_report_bug)
1208 Collect and dump debug information into temporary file if ICE in C/C++
1211 fdump-internal-locations
1212 Common Var(flag_dump_locations) Init(0)
1213 Dump detailed information on GCC's internal representation of source code locations.
1216 Common Var(flag_dump_passes) Init(0)
1217 Dump optimization passes.
1220 Common Report Var(flag_dump_unnumbered)
1221 Suppress output of instruction numbers, line number notes and addresses in debugging dumps.
1223 fdump-unnumbered-links
1224 Common Report Var(flag_dump_unnumbered_links)
1225 Suppress output of previous and next insn numbers in debugging dumps.
1228 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
1229 Enable CFI tables via GAS assembler directives.
1232 Common Report Var(flag_early_inlining) Init(1) Optimization
1233 Perform early inlining.
1235 feliminate-dwarf2-dups
1236 Common Report Var(flag_eliminate_dwarf2_dups)
1237 Perform DWARF duplicate elimination.
1240 Common Report Var(flag_ipa_sra) Init(0) Optimization
1241 Perform interprocedural reduction of aggregates.
1243 feliminate-unused-debug-symbols
1244 Common Report Var(flag_debug_only_used_symbols)
1245 Perform unused symbol elimination in debug info.
1247 feliminate-unused-debug-types
1248 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
1249 Perform unused type elimination in debug info.
1251 femit-class-debug-always
1252 Common Report Var(flag_emit_class_debug_always) Init(0)
1253 Do not suppress C++ class debug information.
1256 Common Report Var(flag_exceptions) Optimization
1257 Enable exception handling.
1259 fexpensive-optimizations
1260 Common Report Var(flag_expensive_optimizations) Optimization
1261 Perform a number of minor, expensive optimizations.
1264 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1265 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision.
1268 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1271 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1274 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1280 Common Var(flag_fat_lto_objects)
1281 Output lto objects containing both the intermediate language and binary output.
1284 Common Report Var(flag_finite_math_only) Optimization SetByCombined
1285 Assume no NaNs or infinities are generated.
1288 Common Joined RejectNegative Var(common_deferred_options) Defer
1289 -ffixed-<register> Mark <register> as being unavailable to the compiler.
1292 Common Report Var(flag_float_store) Optimization
1293 Don't allocate floats and doubles in extended-precision registers.
1297 Does nothing. Preserved for backward compatibility.
1300 Common Report Var(flag_forward_propagate) Optimization
1301 Perform a forward propagation pass on RTL.
1304 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST) Optimization
1305 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1308 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1311 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1313 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1315 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1318 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1320 ; Nonzero means don't put addresses of constant functions in registers.
1321 ; Used for compiling the Unix kernel, where strange substitutions are
1322 ; done on the assembly output.
1324 Common Report Var(flag_no_function_cse,0) Optimization
1325 Allow function addresses to be held in registers.
1328 Common Report Var(flag_function_sections)
1329 Place each function into its own section.
1332 Common Report Var(flag_gcse) Optimization
1333 Perform global common subexpression elimination.
1336 Common Report Var(flag_gcse_lm) Init(1) Optimization
1337 Perform enhanced load motion during global common subexpression elimination.
1340 Common Report Var(flag_gcse_sm) Init(0) Optimization
1341 Perform store motion after global common subexpression elimination.
1344 Common Report Var(flag_gcse_las) Init(0) Optimization
1345 Perform redundant load after store elimination in global common subexpression
1349 Common Report Var(flag_gcse_after_reload) Optimization
1350 Perform global common subexpression elimination after register allocation has
1354 Name(dwarf_gnat_encodings) Type(int)
1357 Enum(dwarf_gnat_encodings) String(all) Value(DWARF_GNAT_ENCODINGS_ALL)
1360 Enum(dwarf_gnat_encodings) String(gdb) Value(DWARF_GNAT_ENCODINGS_GDB)
1363 Enum(dwarf_gnat_encodings) String(minimal) Value(DWARF_GNAT_ENCODINGS_MINIMAL)
1366 Common Enum(dwarf_gnat_encodings) Joined RejectNegative Report Undocumented Var(gnat_encodings)
1367 -fgnat-encodings=[all|gdb|minimal] Select the balance between GNAT encodings and standard DWARF emitted in the debug information
1369 ; This option is not documented yet as its semantics will change.
1371 Common Report Var(flag_graphite) Optimization
1372 Enable in and out of Graphite representation.
1375 Common Report Var(flag_graphite_identity) Optimization
1376 Enable Graphite Identity transformation.
1378 fhoist-adjacent-loads
1379 Common Report Var(flag_hoist_adjacent_loads) Optimization
1380 Enable hoisting adjacent loads to encourage generating conditional move
1383 floop-parallelize-all
1384 Common Report Var(flag_loop_parallelize_all) Optimization
1385 Mark all loops as parallel.
1388 Common Alias(floop-nest-optimize)
1389 Enable loop nest transforms. Same as -floop-nest-optimize.
1392 Common Alias(floop-nest-optimize)
1393 Enable loop nest transforms. Same as -floop-nest-optimize.
1396 Common Alias(floop-nest-optimize)
1397 Enable loop nest transforms. Same as -floop-nest-optimize.
1399 floop-unroll-and-jam
1400 Common Alias(floop-nest-optimize)
1401 Enable loop nest transforms. Same as -floop-nest-optimize.
1404 Common Report Var(flag_tm)
1405 Enable support for GNU transactional memory.
1408 Common Report Var(flag_gnu_unique) Init(1)
1409 Use STB_GNU_UNIQUE if supported by the assembler.
1413 Does nothing. Preserved for backward compatibility.
1416 Common Report Var(flag_loop_nest_optimize) Optimization
1417 Enable the loop nest optimizer.
1419 fstrict-volatile-bitfields
1420 Common Report Var(flag_strict_volatile_bitfields) Init(-1) Optimization
1421 Force bitfield accesses to match their type width.
1423 fguess-branch-probability
1424 Common Report Var(flag_guess_branch_prob) Optimization
1425 Enable guessing of branch probabilities.
1427 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1428 ; Generate position-independent code for executables if possible
1429 ; On SVR4 targets, it also controls whether or not to emit a
1430 ; string identifying the compiler.
1432 Common Report Var(flag_no_ident,0)
1433 Process #ident directives.
1436 Common Report Var(flag_if_conversion) Optimization
1437 Perform conversion of conditional jumps to branchless equivalents.
1440 Common Report Var(flag_if_conversion2) Optimization
1441 Perform conversion of conditional jumps to conditional execution.
1444 Common Joined RejectNegative Enum(stack_reuse_level) Var(flag_stack_reuse) Init(SR_ALL) Optimization
1445 -fstack-reuse=[all|named_vars|none] Set stack reuse level for local variables.
1448 Name(stack_reuse_level) Type(enum stack_reuse_level) UnknownError(unknown Stack Reuse Level %qs)
1451 Enum(stack_reuse_level) String(all) Value(SR_ALL)
1454 Enum(stack_reuse_level) String(named_vars) Value(SR_NAMED_VARS)
1457 Enum(stack_reuse_level) String(none) Value(SR_NONE)
1459 ftree-loop-if-convert
1460 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1461 Convert conditional jumps in innermost loops to branchless equivalents.
1463 ftree-loop-if-convert-stores
1464 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1465 Also if-convert conditional jumps containing memory writes.
1467 ; -finhibit-size-directive inhibits output of .size for ELF.
1468 ; This is used only for compiling crtstuff.c,
1469 ; and it may be extended to other effects
1470 ; needed for crtstuff.c on other systems.
1471 finhibit-size-directive
1472 Common Report Var(flag_inhibit_size_directive)
1473 Do not generate .size directives.
1476 Common Report Var(flag_indirect_inlining) Optimization
1477 Perform indirect inlining.
1479 ; General flag to enable inlining. Specifying -fno-inline will disable
1480 ; all inlining apart from always-inline functions.
1482 Common Report Var(flag_no_inline,0) Init(0) Optimization
1483 Enable inlining of function declared \"inline\", disabling disables all inlining.
1485 finline-small-functions
1486 Common Report Var(flag_inline_small_functions) Optimization
1487 Integrate functions into their callers when code size is known not to grow.
1490 Common Report Var(flag_inline_functions) Optimization
1491 Integrate functions not declared \"inline\" into their callers when profitable.
1493 finline-functions-called-once
1494 Common Report Var(flag_inline_functions_called_once) Optimization
1495 Integrate functions only required by their single caller.
1498 Common RejectNegative Joined Alias(finline-limit=)
1501 Common RejectNegative Joined UInteger
1502 -finline-limit=<number> Limit the size of inlined functions to <number>.
1505 Common Report Var(flag_inline_atomics) Init(1) Optimization
1506 Inline __atomic operations when a lock free instruction sequence is available.
1508 finstrument-functions
1509 Common Report Var(flag_instrument_function_entry_exit)
1510 Instrument function entry and exit with profiling calls.
1512 finstrument-functions-exclude-function-list=
1513 Common RejectNegative Joined
1514 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions.
1516 finstrument-functions-exclude-file-list=
1517 Common RejectNegative Joined
1518 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files.
1521 Common Report Var(flag_ipa_cp) Optimization
1522 Perform interprocedural constant propagation.
1525 Common Report Var(flag_ipa_cp_clone) Optimization
1526 Perform cloning to make Interprocedural constant propagation stronger.
1529 Common Report Var(flag_ipa_cp_alignment) Optimization
1530 Perform alignment discovery and propagation to make Interprocedural constant propagation stronger.
1533 Common Report Var(flag_ipa_profile) Init(0) Optimization
1534 Perform interprocedural profile propagation.
1537 Common Report Var(flag_ipa_pta) Init(0) Optimization
1538 Perform interprocedural points-to analysis.
1541 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1542 Discover pure and const functions.
1545 Common Report Var(flag_ipa_icf) Optimization
1546 Perform Identical Code Folding for functions and read-only variables.
1549 Common Report Var(flag_ipa_icf_functions) Optimization
1550 Perform Identical Code Folding for functions.
1553 Common Report Var(flag_ipa_icf_variables)
1554 Perform Identical Code Folding for variables.
1557 Common Report Var(flag_ipa_reference) Init(0) Optimization
1558 Discover readonly and non addressable static variables.
1562 Does nothing. Preserved for backward compatibility.
1566 Does nothing. Preserved for backward compatibility.
1569 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB) Optimization
1570 -fira-algorithm=[CB|priority] Set the used IRA algorithm.
1573 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1576 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1579 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1582 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_AUTODETECT) Optimization
1583 -fira-region=[one|all|mixed] Set regions for IRA.
1586 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1589 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1592 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1595 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1598 Common Report Var(flag_ira_hoist_pressure) Init(1) Optimization
1599 Use IRA based register pressure calculation
1600 in RTL hoist optimizations.
1603 Common Report Var(flag_ira_loop_pressure) Optimization
1604 Use IRA based register pressure calculation
1605 in RTL loop optimizations.
1607 fira-share-save-slots
1608 Common Report Var(flag_ira_share_save_slots) Init(1) Optimization
1609 Share slots for saving different hard registers.
1611 fira-share-spill-slots
1612 Common Report Var(flag_ira_share_spill_slots) Init(1) Optimization
1613 Share stack slots for spilled pseudo-registers.
1616 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1617 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1620 Common Report Var(flag_ivopts) Init(1) Optimization
1621 Optimize induction variables on trees.
1624 Common Var(flag_jump_tables) Init(1) Optimization
1625 Use jump tables for sufficiently large switch statements.
1627 fkeep-inline-functions
1628 Common Report Var(flag_keep_inline_functions)
1629 Generate code for functions even if they are fully inlined.
1631 fkeep-static-functions
1632 Common Report Var(flag_keep_static_functions)
1633 Generate code for static functions even if they are never called.
1636 Common Report Var(flag_keep_static_consts) Init(1)
1637 Emit static const variables even if they are not used.
1640 Common Report Var(flag_leading_underscore) Init(-1)
1641 Give external symbols a leading underscore.
1645 Does nothing. Preserved for backward compatibility.
1648 Common Report Var(flag_lra_remat) Optimization
1649 Do CFG-sensitive rematerialization in LRA.
1653 Enable link-time optimization.
1656 Common RejectNegative Joined Var(flag_lto)
1657 Link-time optimization with number of parallel jobs or jobserver.
1660 Name(lto_partition_model) Type(enum lto_partition_model) UnknownError(unknown LTO partitioning model %qs)
1663 Enum(lto_partition_model) String(none) Value(LTO_PARTITION_NONE)
1666 Enum(lto_partition_model) String(one) Value(LTO_PARTITION_ONE)
1669 Enum(lto_partition_model) String(balanced) Value(LTO_PARTITION_BALANCED)
1672 Enum(lto_partition_model) String(1to1) Value(LTO_PARTITION_1TO1)
1675 Enum(lto_partition_model) String(max) Value(LTO_PARTITION_MAX)
1678 Common Joined RejectNegative Enum(lto_partition_model) Var(flag_lto_partition) Init(LTO_PARTITION_BALANCED)
1679 Specify the algorithm to partition symbols and vars at linktime.
1681 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1682 flto-compression-level=
1683 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1684 -flto-compression-level=<number> Use zlib compression level <number> for IL.
1686 flto-odr-type-merging
1687 Common Report Var(flag_lto_odr_type_mering) Init(1)
1688 Merge C++ types using One Definition Rule.
1691 Common Report Var(flag_lto_report) Init(0)
1692 Report various link-time optimization statistics.
1695 Common Report Var(flag_lto_report_wpa) Init(0)
1696 Report various link-time optimization statistics for WPA only.
1699 Common Report Var(flag_errno_math) Init(1) Optimization SetByCombined
1700 Set errno after built-in math functions.
1703 Common Joined RejectNegative UInteger Var(flag_max_errors)
1704 -fmax-errors=<number> Maximum number of errors to report.
1707 Common Report Var(mem_report)
1708 Report on permanent memory allocation.
1711 Common Report Var(mem_report_wpa)
1712 Report on permanent memory allocation in WPA only.
1714 ; This will attempt to merge constant section constants, if 1 only
1715 ; string constants and constants from constant pool, if 2 also constant
1717 fmerge-all-constants
1718 Common Report Var(flag_merge_constants,2) Init(1)
1719 Attempt to merge identical constants and constant variables.
1722 Common Report Var(flag_merge_constants,1)
1723 Attempt to merge identical constants across compilation units.
1725 fmerge-debug-strings
1726 Common Report Var(flag_merge_debug_strings) Init(1)
1727 Attempt to merge identical debug strings across compilation units.
1730 Common RejectNegative Joined UInteger
1731 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping.
1734 Common Report Var(flag_modulo_sched) Optimization
1735 Perform SMS based modulo scheduling before the first scheduling pass.
1737 fmodulo-sched-allow-regmoves
1738 Common Report Var(flag_modulo_sched_allow_regmoves) Optimization
1739 Perform SMS based modulo scheduling with register moves allowed.
1741 fmove-loop-invariants
1742 Common Report Var(flag_move_loop_invariants) Optimization
1743 Move loop invariant computations out of loops.
1746 Common Var(flag_dce) Init(1) Optimization
1747 Use the RTL dead code elimination pass.
1750 Common Var(flag_dse) Init(1) Optimization
1751 Use the RTL dead store elimination pass.
1753 freschedule-modulo-scheduled-loops
1754 Common Report Var(flag_resched_modulo_sched) Optimization
1755 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling.
1757 fnon-call-exceptions
1758 Common Report Var(flag_non_call_exceptions) Optimization
1759 Support synchronous non-call exceptions.
1762 Common Driver Joined MissingArgError(options or targets missing after %qs)
1763 -foffload=<targets>=<options> Specify offloading targets and options for them.
1766 Common Joined RejectNegative Enum(offload_abi) Var(flag_offload_abi) Init(OFFLOAD_ABI_UNSET)
1767 -foffload-abi=[lp64|ilp32] Set the ABI to use in an offload compiler.
1770 Name(offload_abi) Type(enum offload_abi) UnknownError(unknown offload ABI %qs)
1773 Enum(offload_abi) String(ilp32) Value(OFFLOAD_ABI_ILP32)
1776 Enum(offload_abi) String(lp64) Value(OFFLOAD_ABI_LP64)
1779 Common Report Var(flag_omit_frame_pointer) Optimization
1780 When possible do not generate stack frames.
1783 Common Report Var(flag_opt_info) Optimization
1784 Enable all optimization info dumps on stderr.
1787 Common Joined RejectNegative Var(common_deferred_options) Defer
1788 -fopt-info[-<type>=filename] Dump compiler optimization details.
1790 foptimize-register-move
1792 Does nothing. Preserved for backward compatibility.
1794 foptimize-sibling-calls
1795 Common Report Var(flag_optimize_sibling_calls) Optimization
1796 Optimize sibling and tail recursive calls.
1799 Common Report Var(flag_partial_inlining) Optimization
1800 Perform partial inlining.
1803 Common Report Var(pre_ipa_mem_report)
1804 Report on memory allocation before interprocedural optimization.
1806 fpost-ipa-mem-report
1807 Common Report Var(post_ipa_mem_report)
1808 Report on memory allocation before interprocedural optimization.
1811 Common Report Var(flag_pack_struct) Optimization
1812 Pack structure members together without holes.
1815 Common RejectNegative Joined UInteger Optimization
1816 -fpack-struct=<number> Set initial maximum structure member alignment.
1819 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1820 Return small aggregates in memory, not registers.
1823 Common Report Var(flag_peel_loops) Optimization
1824 Perform loop peeling.
1827 Common Report Var(flag_no_peephole,0) Optimization
1828 Enable machine specific peephole optimizations.
1831 Common Report Var(flag_peephole2) Optimization
1832 Enable an RTL peephole pass before sched2.
1835 Common Report Var(flag_pic,2) Negative(fPIE)
1836 Generate position-independent code if possible (large mode).
1839 Common Report Var(flag_pie,2) Negative(fpic) Init(-1)
1840 Generate position-independent code for executables if possible (large mode).
1843 Common Report Var(flag_pic,1) Negative(fpie)
1844 Generate position-independent code if possible (small mode).
1847 Common Report Var(flag_pie,1) Negative(fPIC) Init(-1)
1848 Generate position-independent code for executables if possible (small mode).
1851 Common Report Var(flag_plt) Init(1) Optimization
1852 Use PLT for PIC calls (-fno-plt: load the address from GOT at call site).
1855 Common Joined RejectNegative Var(common_deferred_options) Defer
1856 Specify a plugin to load.
1859 Common Joined RejectNegative Var(common_deferred_options) Defer
1860 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>.
1862 fpredictive-commoning
1863 Common Report Var(flag_predictive_commoning) Optimization
1864 Run predictive commoning optimization.
1866 fprefetch-loop-arrays
1867 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1868 Generate prefetch instructions, if available, for arrays in loops.
1871 Common Report Var(profile_flag)
1872 Enable basic program profiling code.
1875 Common Report Var(profile_arc_flag)
1876 Insert arc-based program profiling code.
1879 Common Joined RejectNegative Var(profile_data_prefix)
1880 Set the top-level directory for storing the profile data.
1881 The default is 'pwd'.
1884 Common Report Var(flag_profile_correction)
1885 Enable correction of flow inconsistent profile data input.
1889 Enable common options for generating profile info for profile feedback directed optimizations.
1892 Common Joined RejectNegative
1893 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=.
1896 Common Var(flag_profile_use)
1897 Enable common options for performing profile feedback directed optimizations.
1900 Common Joined RejectNegative
1901 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=.
1904 Common Report Var(flag_profile_values)
1905 Insert code to profile values of expressions.
1908 Common Report Var(profile_report)
1909 Report on consistency of profile.
1911 fprofile-reorder-functions
1912 Common Report Var(flag_profile_reorder_functions)
1913 Enable function reordering that improves code placement.
1916 Common Var(common_deferred_options) Defer
1919 Common Joined RejectNegative Var(common_deferred_options) Defer
1920 -frandom-seed=<string> Make compile reproducible using <string>.
1922 ; This switch causes the command line that was used to create an
1923 ; object file to be recorded into the object file. The exact format
1924 ; of this recording is target and binary file format dependent.
1925 ; It is related to the -fverbose-asm switch, but that switch only
1926 ; records information in the assembler output file as comments, so
1927 ; they never reach the object file.
1928 frecord-gcc-switches
1929 Common Report Var(flag_record_gcc_switches)
1930 Record gcc command line switches in the object file.
1933 Common Report Var(flag_pcc_struct_return,0) Optimization
1934 Return small aggregates in registers.
1938 Does nothing. Preserved for backward compatibility.
1941 Common Report Var(flag_lifetime_dse) Init(1) Optimization
1942 Tell DSE that the storage for a C++ object is dead when the constructor
1943 starts and when the destructor finishes.
1945 flive-range-shrinkage
1946 Common Report Var(flag_live_range_shrinkage) Init(0) Optimization
1947 Relief of register pressure through live range shrinkage.
1950 Common Report Var(flag_rename_registers) Init(2) Optimization
1951 Perform a register renaming optimization pass.
1954 Common Report Var(flag_schedule_fusion) Init(2) Optimization
1955 Perform a target dependent instruction fusion optimization pass.
1958 Common Report Var(flag_reorder_blocks) Optimization
1959 Reorder basic blocks to improve code placement.
1961 freorder-blocks-algorithm=
1962 Common Joined RejectNegative Enum(reorder_blocks_algorithm) Var(flag_reorder_blocks_algorithm) Init(REORDER_BLOCKS_ALGORITHM_SIMPLE) Optimization
1963 -freorder-blocks-algorithm=[simple|stc] Set the used basic block reordering algorithm.
1966 Name(reorder_blocks_algorithm) Type(enum reorder_blocks_algorithm) UnknownError(unknown basic block reordering algorithm %qs)
1969 Enum(reorder_blocks_algorithm) String(simple) Value(REORDER_BLOCKS_ALGORITHM_SIMPLE)
1972 Enum(reorder_blocks_algorithm) String(stc) Value(REORDER_BLOCKS_ALGORITHM_STC)
1974 freorder-blocks-and-partition
1975 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1976 Reorder basic blocks and partition into hot and cold sections.
1979 Common Report Var(flag_reorder_functions) Optimization
1980 Reorder functions to improve code placement.
1982 frerun-cse-after-loop
1983 Common Report Var(flag_rerun_cse_after_loop) Optimization
1984 Add a common subexpression elimination pass after loop optimizations.
1988 Does nothing. Preserved for backward compatibility.
1991 Common Report Var(flag_rounding_math) Optimization SetByCombined
1992 Disable optimizations that assume default FP rounding behavior.
1995 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1996 Enable scheduling across basic blocks.
1999 Common Report Var(flag_sched_pressure) Init(0) Optimization
2000 Enable register pressure sensitive insn scheduling.
2003 Common Report Var(flag_schedule_speculative) Init(1) Optimization
2004 Allow speculative motion of non-loads.
2007 Common Report Var(flag_schedule_speculative_load) Optimization
2008 Allow speculative motion of some loads.
2010 fsched-spec-load-dangerous
2011 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
2012 Allow speculative motion of more loads.
2015 Common RejectNegative Joined UInteger Var(sched_verbose_param) Init(1)
2016 -fsched-verbose=<number> Set the verbosity level of the scheduler.
2018 fsched2-use-superblocks
2019 Common Report Var(flag_sched2_use_superblocks) Optimization
2020 If scheduling post reload, do superblock scheduling.
2024 Does nothing. Preserved for backward compatibility.
2027 Common Report Var(flag_schedule_insns) Optimization
2028 Reschedule instructions before register allocation.
2031 Common Report Var(flag_schedule_insns_after_reload) Optimization
2032 Reschedule instructions after register allocation.
2034 ; This flag should be on when a target implements non-trivial
2035 ; scheduling hooks, maybe saving some information for its own sake.
2036 ; On IA64, for example, this is used for correct bundling.
2037 fselective-scheduling
2038 Common Report Var(flag_selective_scheduling) Optimization
2039 Schedule instructions using selective scheduling algorithm.
2041 fselective-scheduling2
2042 Common Report Var(flag_selective_scheduling2) Optimization
2043 Run selective scheduling after reload.
2045 fsel-sched-pipelining
2046 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
2047 Perform software pipelining of inner loops during selective scheduling.
2049 fsel-sched-pipelining-outer-loops
2050 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
2051 Perform software pipelining of outer loops during selective scheduling.
2053 fsel-sched-reschedule-pipelined
2054 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
2055 Reschedule pipelined regions without pipelining.
2057 fsemantic-interposition
2058 Common Report Var(flag_semantic_interposition) Init(1)
2059 Allow interposing function (or variables) by ones with different semantics (or initializer) respectively by dynamic linker.
2061 ; sched_stalled_insns means that insns can be moved prematurely from the queue
2062 ; of stalled insns into the ready list.
2063 fsched-stalled-insns
2064 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
2065 Allow premature scheduling of queued insns.
2067 fsched-stalled-insns=
2068 Common RejectNegative Joined UInteger Optimization
2069 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled.
2071 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
2072 ; be examined for a dependency on a stalled insn that is candidate for
2073 ; premature removal from the queue of stalled insns into the ready list (has
2074 ; an effect only if the flag 'sched_stalled_insns' is set).
2075 fsched-stalled-insns-dep
2076 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
2077 Set dependence distance checking in premature scheduling of queued insns.
2079 fsched-stalled-insns-dep=
2080 Common RejectNegative Joined UInteger Optimization
2081 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns.
2083 fsched-group-heuristic
2084 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
2085 Enable the group heuristic in the scheduler.
2087 fsched-critical-path-heuristic
2088 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
2089 Enable the critical path heuristic in the scheduler.
2091 fsched-spec-insn-heuristic
2092 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
2093 Enable the speculative instruction heuristic in the scheduler.
2095 fsched-rank-heuristic
2096 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
2097 Enable the rank heuristic in the scheduler.
2099 fsched-last-insn-heuristic
2100 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
2101 Enable the last instruction heuristic in the scheduler.
2103 fsched-dep-count-heuristic
2104 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
2105 Enable the dependent count heuristic in the scheduler.
2108 Common Report Var(flag_section_anchors) Optimization
2109 Access data in the same section from shared anchor points.
2113 Does nothing. Preserved for backward compatibility.
2117 Does nothing. Preserved for backward compatibility.
2120 Common Report Var(flag_ree) Init(0)
2121 Turn on Redundant Extensions Elimination pass.
2124 Common Report Var(flag_show_column) Init(1)
2125 Show column numbers in diagnostics, when available. Default on.
2128 Common Report Var(flag_shrink_wrap) Optimization
2129 Emit function prologues only before parts of the function that need it,
2130 rather than at the top of the function.
2133 Common Report Var(flag_signaling_nans) Optimization SetByCombined
2134 Disable optimizations observable by IEEE signaling NaNs.
2137 Common Report Var(flag_signed_zeros) Init(1) Optimization SetByCombined
2138 Disable floating point optimizations that ignore the IEEE signedness of zero.
2140 fsingle-precision-constant
2141 Common Report Var(flag_single_precision_constant) Optimization
2142 Convert floating point constants to single precision constants.
2144 fsplit-ivs-in-unroller
2145 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
2146 Split lifetimes of induction variables when loops are unrolled.
2149 Common Report Var(flag_split_stack) Init(-1)
2150 Generate discontiguous stack frames.
2153 Common Report Var(flag_split_wide_types) Optimization
2154 Split wide types into independent registers.
2157 Common Report Var(flag_ssa_backprop) Init(1) Optimization
2158 Enable backward propagation of use properties at the SSA level.
2161 Common Report Var(flag_ssa_phiopt) Optimization
2162 Optimize conditional patterns using SSA PHI nodes.
2165 Common Report Var(flag_stdarg_opt) Init(1) Optimization
2166 Optimize amount of stdarg registers saved to stack at start of function.
2168 fvariable-expansion-in-unroller
2169 Common Report Var(flag_variable_expansion_in_unroller) Optimization
2170 Apply variable expansion when loops are unrolled.
2173 Common Report RejectNegative Joined
2174 -fstack-check=[no|generic|specific] Insert stack checking code into the program.
2177 Common Alias(fstack-check=, specific, no)
2178 Insert stack checking code into the program. Same as -fstack-check=specific.
2181 Common Var(common_deferred_options) Defer
2183 fstack-limit-register=
2184 Common RejectNegative Joined Var(common_deferred_options) Defer
2185 -fstack-limit-register=<register> Trap if the stack goes past <register>.
2187 fstack-limit-symbol=
2188 Common RejectNegative Joined Var(common_deferred_options) Defer
2189 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>.
2192 Common Report Var(flag_stack_protect, 1) Init(-1)
2193 Use propolice as a stack protection method.
2195 fstack-protector-all
2196 Common Report RejectNegative Var(flag_stack_protect, 2) Init(-1)
2197 Use a stack protection method for every function.
2199 fstack-protector-strong
2200 Common Report RejectNegative Var(flag_stack_protect, 3) Init(-1)
2201 Use a smart stack protection method for certain functions.
2203 fstack-protector-explicit
2204 Common Report RejectNegative Var(flag_stack_protect, 4)
2205 Use stack protection method only for functions with the stack_protect attribute.
2208 Common RejectNegative Var(flag_stack_usage)
2209 Output stack usage information on a per-function basis.
2213 Does nothing. Preserved for backward compatibility.
2215 ; Nonzero if we should do (language-dependent) alias analysis.
2216 ; Typically, this analysis will assume that expressions of certain
2217 ; types do not alias expressions of certain other types. Only used
2218 ; if alias analysis (in general) is enabled.
2220 Common Report Var(flag_strict_aliasing) Optimization
2221 Assume strict aliasing rules apply.
2224 Common Report Var(flag_strict_overflow) Optimization
2225 Treat signed overflow as undefined.
2228 Common Report Var(flag_sync_libcalls) Init(1)
2229 Implement __atomic operations via libcalls to legacy __sync functions.
2232 Common Report Var(flag_syntax_only)
2233 Check for syntax errors, then stop.
2236 Common Report Var(flag_test_coverage)
2237 Create data files needed by \"gcov\".
2240 Common Report Var(flag_thread_jumps) Optimization
2241 Perform jump threading optimizations.
2244 Common Report Var(time_report)
2245 Report the time taken by each compiler pass.
2248 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
2249 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model.
2252 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
2255 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
2258 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
2261 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
2264 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
2267 Common Report Var(flag_toplevel_reorder) Init(2)
2268 Reorder top level functions, variables, and asms.
2271 Common Report Var(flag_tracer) Optimization
2272 Perform superblock formation via tail duplication.
2274 ; Zero means that floating-point math operations cannot generate a
2275 ; (user-visible) trap. This is the case, for example, in nonstop
2276 ; IEEE 754 arithmetic.
2278 Common Report Var(flag_trapping_math) Init(1) Optimization SetByCombined
2279 Assume floating-point operations can trap.
2282 Common Report Var(flag_trapv) Optimization
2283 Trap for signed overflow in addition, subtraction and multiplication.
2286 Common Report Var(flag_tree_ccp) Optimization
2287 Enable SSA-CCP optimization on trees.
2290 Common Report Var(flag_tree_bit_ccp) Optimization
2291 Enable SSA-BIT-CCP optimization on trees.
2295 Does nothing. Preserved for backward compatibility.
2298 Common Report Var(flag_tree_ch) Optimization
2299 Enable loop header copying on trees.
2301 ftree-coalesce-inlined-vars
2302 Common Ignore RejectNegative
2303 Does nothing. Preserved for backward compatibility.
2306 Common Report Var(flag_tree_coalesce_vars) Optimization
2307 Enable SSA coalescing of user variables.
2311 Does nothing. Preserved for backward compatibility.
2314 Common Report Var(flag_tree_copy_prop) Optimization
2315 Enable copy propagation on trees.
2317 ftree-store-copy-prop
2319 Does nothing. Preserved for backward compatibility.
2322 Common Report Var(flag_tree_cselim) Init(2) Optimization
2323 Transform condition stores into unconditional ones.
2325 ftree-switch-conversion
2326 Common Report Var(flag_tree_switch_conversion) Optimization
2327 Perform conversions of switch initializations.
2330 Common Report Var(flag_tree_dce) Optimization
2331 Enable SSA dead code elimination optimization on trees.
2333 ftree-dominator-opts
2334 Common Report Var(flag_tree_dom) Optimization
2335 Enable dominator optimizations.
2338 Common Report Var(flag_tree_tail_merge) Optimization
2339 Enable tail merging on trees.
2342 Common Report Var(flag_tree_dse) Optimization
2343 Enable dead store elimination.
2346 Common Report Var(flag_tree_forwprop) Init(1) Optimization
2347 Enable forward propagation on trees.
2350 Common Report Var(flag_tree_fre) Optimization
2351 Enable Full Redundancy Elimination (FRE) on trees.
2354 Common Report Var(flag_optimize_strlen) Optimization
2355 Enable string length optimizations on trees.
2357 fisolate-erroneous-paths-dereference
2358 Common Report Var(flag_isolate_erroneous_paths_dereference) Optimization
2359 Detect paths that trigger erroneous or undefined behavior due to
2360 dereferencing a null pointer. Isolate those paths from the main control
2361 flow and turn the statement with erroneous or undefined behavior into a trap.
2363 fisolate-erroneous-paths-attribute
2364 Common Report Var(flag_isolate_erroneous_paths_attribute) Optimization
2365 Detect paths that trigger erroneous or undefined behavior due a null value
2366 being used in a way forbidden by a returns_nonnull or nonnull
2367 attribute. Isolate those paths from the main control flow and turn the
2368 statement with erroneous or undefined behavior into a trap.
2370 ftree-loop-distribution
2371 Common Report Var(flag_tree_loop_distribution) Optimization
2372 Enable loop distribution on trees.
2374 ftree-loop-distribute-patterns
2375 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
2376 Enable loop distribution for patterns transformed into a library call.
2379 Common Report Var(flag_tree_loop_im) Init(1) Optimization
2380 Enable loop invariant motion on trees.
2383 Common Alias(floop-nest-optimize)
2384 Enable loop nest transforms. Same as -floop-nest-optimize.
2387 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
2388 Create canonical induction variables in loops.
2391 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
2392 Enable loop optimizations on tree level.
2394 ftree-parallelize-loops=
2395 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1) Optimization
2396 Enable automatic parallelization of loops.
2399 Common Report Var(flag_tree_phiprop) Init(1) Optimization
2400 Enable hoisting loads from conditional pointers.
2403 Common Report Var(flag_tree_pre) Optimization
2404 Enable SSA-PRE optimization on trees.
2407 Common Report Var(flag_tree_partial_pre) Optimization
2408 In SSA-PRE optimization on trees, enable partial-partial redundancy elimination.
2411 Common Report Var(flag_tree_pta) Optimization
2412 Perform function-local points-to analysis on trees.
2415 Common Report Var(flag_tree_reassoc) Init(1) Optimization
2416 Enable reassociation on tree level.
2420 Does nothing. Preserved for backward compatibility.
2423 Common Report Var(flag_tree_sink) Optimization
2424 Enable SSA code sinking on trees.
2427 Common Report Var(flag_tree_slsr) Optimization
2428 Perform straight-line strength reduction.
2431 Common Report Var(flag_tree_sra) Optimization
2432 Perform scalar replacement of aggregates.
2435 Common Report Var(flag_tree_ter) Optimization
2436 Replace temporary expressions in the SSA->normal pass.
2439 Common Report Var(flag_tree_live_range_split) Optimization
2440 Perform live range splitting during the SSA->normal pass.
2443 Common Report Var(flag_tree_vrp) Init(0) Optimization
2444 Perform Value Range Propagation on trees.
2447 Common Report Var(flag_split_paths) Init(0) Optimization
2448 Split paths leading to loop backedges.
2451 Common Report Var(flag_unit_at_a_time) Init(1)
2452 Compile whole compilation unit at a time.
2455 Common Report Var(flag_unroll_loops) Optimization
2456 Perform loop unrolling when iteration count is known.
2459 Common Report Var(flag_unroll_all_loops) Optimization
2460 Perform loop unrolling for all loops.
2462 ; Nonzero means that loop optimizer may assume that the induction variables
2463 ; that control loops do not overflow and that the loops with nontrivial
2464 ; exit condition are not infinite
2465 funsafe-loop-optimizations
2466 Common Report Var(flag_unsafe_loop_optimizations) Optimization
2467 Allow loop optimizations to assume that the loops behave in normal way.
2470 Common Report Var(flag_associative_math) SetByCombined Optimization
2471 Allow optimization for floating-point arithmetic which may change the
2472 result of the operation due to rounding.
2475 Common Report Var(flag_reciprocal_math) SetByCombined Optimization
2476 Same as -fassociative-math for expressions which include division.
2478 ; Nonzero means that unsafe floating-point math optimizations are allowed
2479 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
2480 ; are allowed to assume that their arguments and results are "normal"
2481 ; (e.g., nonnegative for SQRT).
2482 funsafe-math-optimizations
2483 Common Report Var(flag_unsafe_math_optimizations) Optimization SetByCombined
2484 Allow math optimizations that may violate IEEE or ISO standards.
2487 Common Report Var(flag_unswitch_loops) Optimization
2488 Perform loop unswitching.
2491 Common Report Var(flag_unwind_tables) Optimization
2492 Just generate unwind tables for exception handling.
2495 Common Driver Negative(fuse-ld=gold)
2496 Use the bfd linker instead of the default linker.
2499 Common Driver Negative(fuse-ld=bfd)
2500 Use the gold linker instead of the default linker.
2503 Common Undocumented Var(flag_use_linker_plugin)
2505 ; Positive if we should track variables, negative if we should run
2506 ; the var-tracking pass only to discard debug annotations, zero if
2507 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2508 ; will be set according to optimize, debug_info_level and debug_hooks
2509 ; in process_options ().
2511 Common Report Var(flag_var_tracking) Init(2) Optimization
2512 Perform variable tracking.
2514 ; Positive if we should track variables at assignments, negative if
2515 ; we should run the var-tracking pass only to discard debug
2516 ; annotations. When flag_var_tracking_assignments ==
2517 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2518 fvar-tracking-assignments
2519 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2520 Perform variable tracking by annotating assignments.
2522 ; Nonzero if we should toggle flag_var_tracking_assignments after
2523 ; processing options and computing its default. */
2524 fvar-tracking-assignments-toggle
2525 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2526 Toggle -fvar-tracking-assignments.
2528 ; Positive if we should track uninitialized variables, negative if
2529 ; we should run the var-tracking pass only to discard debug
2530 ; annotations. When flag_var_tracking_uninit == AUTODETECT_VALUE it
2531 ; will be set according to flag_var_tracking.
2532 fvar-tracking-uninit
2533 Common Report Var(flag_var_tracking_uninit) Optimization
2534 Perform variable tracking and also tag variables that are uninitialized.
2537 Common Report Var(flag_tree_vectorize) Optimization
2538 Enable vectorization on trees.
2540 ftree-vectorizer-verbose=
2541 Common Joined RejectNegative Ignore
2542 Does nothing. Preserved for backward compatibility.
2544 ftree-loop-vectorize
2545 Common Report Var(flag_tree_loop_vectorize) Optimization
2546 Enable loop vectorization on trees.
2549 Common Report Var(flag_tree_slp_vectorize) Optimization
2550 Enable basic block vectorization (SLP) on trees.
2553 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_vect_cost_model) Init(VECT_COST_MODEL_DEFAULT) Optimization
2554 Specifies the cost model for vectorization.
2557 Common Joined RejectNegative Enum(vect_cost_model) Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED) Optimization
2558 Specifies the vectorization cost model for code marked with a simd directive.
2561 Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown vectorizer cost model %qs)
2564 Enum(vect_cost_model) String(unlimited) Value(VECT_COST_MODEL_UNLIMITED)
2567 Enum(vect_cost_model) String(dynamic) Value(VECT_COST_MODEL_DYNAMIC)
2570 Enum(vect_cost_model) String(cheap) Value(VECT_COST_MODEL_CHEAP)
2573 Common RejectNegative Alias(fvect-cost-model=,dynamic)
2574 Enables the dynamic vectorizer cost model. Preserved for backward compatibility.
2577 Common RejectNegative Alias(fvect-cost-model=,unlimited)
2578 Enables the unlimited vectorizer cost model. Preserved for backward compatibility.
2580 ftree-vect-loop-version
2582 Does nothing. Preserved for backward compatibility.
2585 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2586 Enable copy propagation of scalar-evolution information.
2588 ; -fverbose-asm causes extra commentary information to be produced in
2589 ; the generated assembly code (to make it more readable). This option
2590 ; is generally only of use to those who actually need to read the
2591 ; generated assembly code (perhaps while debugging the compiler itself).
2592 ; -fno-verbose-asm, the default, causes the extra information
2593 ; to not be added and is useful when comparing two assembler files.
2595 Common Report Var(flag_verbose_asm)
2596 Add extra commentary to assembler output.
2599 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2600 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility.
2603 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2606 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2609 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2612 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2615 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2618 Common Joined RejectNegative Enum(vtv_priority) Var(flag_vtable_verify) Init(VTV_NO_PRIORITY)
2619 Validate vtable pointers before using them.
2622 Name(vtv_priority) Type(enum vtv_priority) UnknownError(unknown vtable verify initialization priority %qs)
2625 Enum(vtv_priority) String(none) Value(VTV_NO_PRIORITY)
2628 Enum(vtv_priority) String(std) Value(VTV_STANDARD_PRIORITY)
2631 Enum(vtv_priority) String(preinit) Value(VTV_PREINIT_PRIORITY)
2634 Common Var(flag_vtv_counts)
2635 Output vtable verification counters.
2638 Common Var(flag_vtv_debug)
2639 Output vtable verification pointer sets information.
2642 Common Report Var(flag_value_profile_transformations) Optimization
2643 Use expression value profiles in optimizations.
2646 Common Report Var(flag_web) Init(2) Optimization
2647 Construct webs and split unrelated uses of single variable.
2649 ftree-builtin-call-dce
2650 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2651 Enable conditional dead code elimination for builtin calls.
2654 Common Report Var(flag_whole_program) Init(0)
2655 Perform whole program optimizations.
2658 Common Report Var(flag_wrapv) Optimization
2659 Assume signed arithmetic overflow wraps around.
2661 fzero-initialized-in-bss
2662 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2663 Put zero initialized data in the bss section.
2666 Common JoinedOrMissing
2667 Generate debug information in default format.
2670 Common JoinedOrMissing Negative(gdwarf)
2671 Generate debug information in COFF format.
2674 Common JoinedOrMissing Negative(gdwarf-)
2675 Generate debug information in default version of DWARF format.
2678 Common Joined UInteger Var(dwarf_version) Init(4) Negative(gstabs)
2679 Generate debug information in DWARF v2 (or later) format.
2682 Common JoinedOrMissing
2683 Generate debug information in default extended format.
2686 Common Negative(gpubnames) Var(debug_generate_pub_sections, 0) Init(-1)
2687 Don't generate DWARF pubnames and pubtypes sections.
2690 Common Negative(ggnu-pubnames) Var(debug_generate_pub_sections, 1)
2691 Generate DWARF pubnames and pubtypes sections.
2694 Common Negative(gno-pubnames) Var(debug_generate_pub_sections, 2)
2695 Generate DWARF pubnames and pubtypes sections with GNU extensions.
2697 gno-record-gcc-switches
2698 Common RejectNegative Var(dwarf_record_gcc_switches,0) Init(1)
2699 Don't record gcc command line switches in DWARF DW_AT_producer.
2701 grecord-gcc-switches
2702 Common RejectNegative Var(dwarf_record_gcc_switches,1)
2703 Record gcc command line switches in DWARF DW_AT_producer.
2706 Common Driver RejectNegative Var(dwarf_split_debug_info,0) Init(0)
2707 Don't generate debug information in separate .dwo files.
2710 Common Driver RejectNegative Var(dwarf_split_debug_info,1)
2711 Generate debug information in separate .dwo files.
2714 Common JoinedOrMissing Negative(gstabs+)
2715 Generate debug information in STABS format.
2718 Common JoinedOrMissing Negative(gvms)
2719 Generate debug information in extended STABS format.
2722 Common RejectNegative Var(dwarf_strict,0) Init(0)
2723 Emit DWARF additions beyond selected version.
2726 Common Report RejectNegative Var(dwarf_strict,1)
2727 Don't emit DWARF additions beyond selected version.
2730 Common Report Var(flag_gtoggle)
2731 Toggle debug information generation.
2734 Common JoinedOrMissing Negative(gxcoff)
2735 Generate debug information in VMS format.
2738 Common JoinedOrMissing Negative(gxcoff+)
2739 Generate debug information in XCOFF format.
2742 Common JoinedOrMissing Negative(gcoff)
2743 Generate debug information in extended XCOFF format.
2746 Name(compressed_debug_sections) Type(int)
2748 ; Since -gz= is completely handled in specs, the values aren't used and we
2749 ; assign arbitrary constants.
2751 Enum(compressed_debug_sections) String(none) Value(0)
2754 Enum(compressed_debug_sections) String(zlib) Value(1)
2757 Enum(compressed_debug_sections) String(zlib-gnu) Value(2)
2761 Generate compressed debug sections.
2764 Common Driver Joined Enum(compressed_debug_sections)
2765 -gz=<format> Generate compressed debug sections in format <format>.
2768 Driver Joined Separate
2771 Common Joined Var(plugindir_string) Init(0)
2772 -iplugindir=<dir> Set <dir> to be the default plugin directory.
2775 Common Joined Separate RejectDriver Var(imultiarch) Init(0)
2776 -imultiarch <dir> Set <dir> to be the multiarch include subdirectory.
2779 Driver Joined Separate
2784 no-canonical-prefixes
2797 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2798 -o <file> Place output into <file>.
2801 Common Var(profile_flag)
2802 Enable function profiling.
2805 Driver Var(pass_exit_codes)
2808 Common Alias(Wpedantic)
2811 Common Var(flag_pedantic_errors)
2812 Like -pedantic but issue them as errors.
2818 Driver Var(use_pipes)
2821 Driver JoinedOrMissing Var(print_file_name)
2823 print-libgcc-file-name
2826 print-multi-directory
2827 Driver Var(print_multi_directory)
2830 Driver Var(print_multi_lib)
2832 print-multi-os-directory
2833 Driver Var(print_multi_os_directory)
2836 Driver Var(print_multiarch)
2839 Driver JoinedOrMissing Var(print_prog_name)
2842 Driver Var(print_search_dirs)
2845 Driver Var(print_sysroot)
2847 print-sysroot-headers-suffix
2848 Driver Var(print_sysroot_headers_suffix)
2851 Common Var(quiet_flag) RejectDriver
2852 Do not display functions compiled or elapsed time.
2870 Driver Var(report_times)
2873 Driver JoinedOrMissing
2876 Driver Joined Separate
2880 ; C option, but driver must not handle as "-u ndef".
2883 Common Driver Var(verbose_flag)
2884 Enable verbose output.
2887 Common Var(version_flag) RejectDriver
2888 Display the compiler's version.
2891 Common Var(inhibit_warnings)
2895 Driver Separate Var(wrapper_string)
2898 Driver Joined Separate
2901 Driver RejectNegative Negative(pie)
2902 Create a shared library.
2908 Driver Separate Alias(specs=)
2921 ; Documented for Fortran, but always accepted by driver.
2928 ; Documented for Go, but always accepted by driver.
2946 Driver RejectNegative Negative(shared)
2947 Don't create a position independent executable.
2950 Driver RejectNegative Negative(no-pie)
2951 Create a position independent executable.
2954 Driver Joined Separate
2957 Common Report Var(flag_ipa_ra) Optimization
2958 Use caller save register across calls if possible.
2960 ; This comment is to ensure we retain the blank line above.