1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
4 ; Free Software Foundation, Inc.
6 ; This file is part of GCC.
8 ; GCC is free software; you can redistribute it and/or modify it under
9 ; the terms of the GNU General Public License as published by the Free
10 ; Software Foundation; either version 3, or (at your option) any later
13 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 ; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 ; You should have received a copy of the GNU General Public License
19 ; along with GCC; see the file COPYING3. If not see
20 ; <http://www.gnu.org/licenses/>.
22 ; See the GCC internals manual (options.texi) for a description of this file's format.
24 ; Please try to keep this file in ASCII collating order.
35 ; 0 means straightforward implementation of complex divide acceptable.
36 ; 1 means wide ranges of inputs must work for complex divide.
37 ; 2 means C99-like requirements for complex multiply and divide.
39 int flag_complex_method = 1
41 ; Nonzero if subexpressions must be evaluated from left-to-right.
43 int flag_evaluation_order = 0
45 ; Set the default region and algorithm for the integrated register
49 enum ira_algorithm flag_ira_algorithm = IRA_ALGORITHM_CB
52 enum ira_region flag_ira_region = IRA_REGION_MIXED
54 ; Language specific warning pass for unused results.
56 bool flag_warn_unused_result = false
61 ; Floating-point contraction mode, fast by default.
63 enum fp_contract_mode flag_fp_contract_mode = FP_CONTRACT_FAST
65 ; The excess precision specified on the command line, or defaulted by
68 enum excess_precision flag_excess_precision_cmdline = EXCESS_PRECISION_DEFAULT
70 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
74 ; True to warn about any objects definitions whose size is larger
75 ; than N bytes. Also want about function definitions whose returned
76 ; values are larger than N bytes, where N is 'larger_than_size'.
81 HOST_WIDE_INT larger_than_size
83 ; True to warn about any function whose frame size is larger
86 bool warn_frame_larger_than
89 HOST_WIDE_INT frame_larger_than_size
91 ; Nonzero means we should be saving declaration info into a .X file.
93 int flag_gen_aux_info = 0
95 ; Nonzero if we are compiling code for a shared library, zero for
100 ; The default visibility for all symbols (unless overridden).
102 enum symbol_visibility default_visibility = VISIBILITY_DEFAULT
104 ; Set to the default thread-local storage (tls) model to use.
106 enum tls_model flag_tls_default = TLS_MODEL_GLOBAL_DYNAMIC
108 ; These two are really VEC(char_p,heap) *.
111 void *flag_instrument_functions_exclude_functions
114 void *flag_instrument_functions_exclude_files
116 ; Generic structs (e.g. templates not explicitly specialized)
117 ; may not have a compilation unit associated with them, and so
118 ; may need to be treated differently from ordinary structs.
120 ; Structs only handled by reference (indirectly), will also usually
121 ; not need as much debugging information.
124 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
127 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
129 ; True if we should exit after parsing options.
131 bool exit_after_options
133 ; Type(s) of debugging information we are producing (if any). See
134 ; flag-types.h for the definitions of the different possible types of
135 ; debugging information.
137 enum debug_info_type write_symbols = NO_DEBUG
139 ; Level of debugging information we are producing. See flag-types.h
140 ; for the definitions of the different possible levels.
142 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
144 ; Nonzero means use GNU-only extensions in the generated symbolic
145 ; debugging information. Currently, this only has an effect when
146 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
148 bool use_gnu_debug_info_extensions
150 ; Original value of maximum field alignment in bytes, specified via
151 ; -fpack-struct=<value>.
153 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
155 ; -dA causes debug commentary information to be produced in
156 ; the generated assembly code (to make it more readable). This option
157 ; is generally only of use to those who actually need to read the
158 ; generated assembly code (perhaps while debugging the compiler itself).
159 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
160 ; to be a catchall for printing debug information in the assembler file.
164 ; -dP causes the rtl to be emitted as a comment in assembly.
166 int flag_dump_rtl_in_asm
168 ; Whether -da was passed (used only in handle_common_deferred_options).
170 bool flag_dump_all_passed
172 ; Other flags saying which kinds of debugging dump have been requested.
175 int rtl_dump_and_exit
178 int flag_print_asm_name
181 enum graph_dump_types graph_dump_format = no_graph
183 ; Which options have been printed by --help.
187 ; The number of columns for --help output.
189 unsigned int help_columns
191 ; Whether this options structure has been through finish_options
193 bool flag_opts_finished
205 Driver Alias(coverage)
211 Common Separate Alias(d)
214 Common Joined Alias(d)
217 Common Separate Alias(dumpbase)
220 Common Separate Alias(dumpdir)
223 Driver Separate Alias(e)
226 Driver Joined Alias(e)
229 Common Warning Alias(Wextra)
232 Driver Separate Alias(Xassembler)
235 Driver JoinedOrMissing Alias(Xassembler)
238 Driver Separate Alias(Xlinker)
241 Driver JoinedOrMissing Alias(Xlinker)
244 Driver Separate Alias(u)
247 Driver Joined Alias(u)
250 Common Driver Var(help_flag)
251 Display this information
254 Common Driver Report Joined
255 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params
258 Driver Separate Alias(x)
261 Driver Joined Alias(x)
264 Driver Separate Alias(L)
267 Driver Joined Alias(L)
269 -no-canonical-prefixes
270 Driver Alias(no-canonical-prefixes)
272 -no-standard-libraries
273 Driver Alias(nostdlib)
282 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
285 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
288 Driver Alias(pass-exit-codes)
291 Common Alias(pedantic)
294 Common Alias(pedantic-errors)
303 Driver Separate Alias(B)
306 Driver JoinedOrMissing Alias(B)
312 Driver Separate Alias(print-file-name=)
315 Driver JoinedOrMissing Alias(print-file-name=)
317 -print-libgcc-file-name
318 Driver Alias(print-libgcc-file-name)
320 -print-multi-directory
321 Driver Alias(print-multi-directory)
324 Driver Alias(print-multi-lib)
326 -print-multi-os-directory
327 Driver Alias(print-multi-os-directory)
330 Driver Separate Alias(print-prog-name=)
333 Driver JoinedOrMissing Alias(print-prog-name=)
336 Driver Alias(print-search-dirs)
339 Driver Alias(print-sysroot)
341 -print-sysroot-headers-suffix
342 Driver Alias(print-sysroot-headers-suffix)
348 Driver Alias(save-temps)
354 Driver Separate Alias(specs=)
357 Driver Joined Alias(specs=)
363 Driver Alias(symbolic)
367 Alias for --help=target
375 ;; The driver used to convert options such as --help into forms such
376 ;; as -fhelp; the following four entries are for compatibility with
377 ;; any direct uses of those (undocumented) -f forms
379 Common Driver Alias(-help)
382 Common Driver Joined Alias(-help=)
385 Common Driver Alias(-target-help)
388 Common Driver Alias(-version)
392 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
395 Common Joined Alias(-param)
398 Driver Separate Alias(-sysroot=)
401 Driver JoinedOrMissing
407 Driver Joined Separate
413 Driver Joined Separate
416 Common JoinedOrMissing Optimization
417 -O<number> Set optimization level to <number>
421 Optimize for space rather than speed
425 Optimize for speed disregarding exact standards compliance
428 Driver Joined Separate
434 Driver Joined Separate
446 Common RejectNegative Warning Alias(Wextra)
447 This switch is deprecated; use -Wextra instead
450 Driver JoinedOrMissing
453 Driver JoinedOrMissing
456 Driver JoinedOrMissing
459 Common Var(warn_aggregate_return) Warning
460 Warn about returning structures, unions or arrays
463 Common Var(warn_array_bounds) Warning
464 Warn if an array is accessed out of bounds
467 Common Var(warn_attributes) Init(1) Warning
468 Warn about inappropriate attribute usage
471 Common Var(warn_cast_align) Warning
472 Warn about pointer casts which increase alignment
475 Common Var(warn_cpp) Init(1) Warning
476 Warn when a #warning directive is encountered
478 Wdeprecated-declarations
479 Common Var(warn_deprecated_decl) Init(1) Warning
480 Warn about uses of __attribute__((deprecated)) declarations
482 Wdisabled-optimization
483 Common Var(warn_disabled_optimization) Warning
484 Warn when an optimization pass is disabled
487 Common Var(warnings_are_errors)
488 Treat all warnings as errors
492 Treat specified warning as error
495 Common Var(extra_warnings) Warning
496 Print extra (possibly unwanted) warnings
499 Common Var(flag_fatal_errors)
500 Exit on the first error occurred
503 Common RejectNegative Joined UInteger
504 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
507 Common Var(warn_inline) Warning
508 Warn when an inlined function cannot be inlined
511 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
514 Common RejectNegative Joined UInteger Warning
515 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
517 Wunsafe-loop-optimizations
518 Common Var(warn_unsafe_loop_optimizations) Warning
519 Warn if the loop cannot be optimized due to nontrivial assumptions.
522 Common Var(warn_missing_noreturn) Warning
523 Warn about functions which might be candidates for __attribute__((noreturn))
526 Common Var(warn_mudflap) Init(1) Warning
527 Warn about constructs not instrumented by -fmudflap
530 Common Var(warn_overflow) Init(1) Warning
531 Warn about overflow in arithmetic expressions
534 Common Var(warn_packed) Warning
535 Warn when the packed attribute has no effect on struct layout
538 Common Var(warn_padded) Warning
539 Warn when padding is required to align structure members
542 Common Var(warn_shadow) Warning
543 Warn when one local variable shadows another
546 Common Var(warn_stack_protect) Warning
547 Warn when not issuing stack smashing protection for some reason
551 Warn about code which might break strict aliasing rules
554 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Init(-1) Warning
555 Warn about code which might break strict aliasing rules
559 Warn about optimizations that assume that signed overflow is undefined
562 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Init(-1) Warning
563 Warn about optimizations that assume that signed overflow is undefined
565 Wsuggest-attribute=const
566 Common Var(warn_suggest_attribute_const) Warning
567 Warn about functions which might be candidates for __attribute__((const))
569 Wsuggest-attribute=pure
570 Common Var(warn_suggest_attribute_pure) Warning
571 Warn about functions which might be candidates for __attribute__((pure))
573 Wsuggest-attribute=noreturn
574 Common Var(warn_suggest_attribute_noreturn) Warning
575 Warn about functions which might be candidates for __attribute__((noreturn))
578 Common Var(warn_switch) Warning
579 Warn about enumerated switches, with no default, missing a case
582 Common Var(warn_switch_default) Warning
583 Warn about enumerated switches missing a \"default:\" statement
586 Common Var(warn_switch_enum) Warning
587 Warn about all enumerated switches missing a specific case
590 Common Var(warn_system_headers) Warning
591 Do not suppress warnings from system headers
594 Common Var(warn_trampolines) Warning
595 Warn whenever a trampoline is generated
598 Common Var(warn_type_limits) Init(-1) Warning
599 Warn if a comparison is always true or always false due to the limited range of the data type
602 Common Var(warn_uninitialized) Init(-1) Warning
603 Warn about uninitialized automatic variables
607 Does nothing. Preserved for backward compatibility.
610 Common Var(warn_unused) Init(0) Warning
611 Enable all -Wunused- warnings
613 Wunused-but-set-parameter
614 Common Var(warn_unused_but_set_parameter) Init(-1) Warning
615 Warn when a function parameter is only set, otherwise unused
617 Wunused-but-set-variable
618 Common Var(warn_unused_but_set_variable) Init(-1) Warning
619 Warn when a variable is only set, otherwise unused
622 Common Var(warn_unused_function) Init(-1) Warning
623 Warn when a function is unused
626 Common Var(warn_unused_label) Init(-1) Warning
627 Warn when a label is unused
630 Common Var(warn_unused_parameter) Init(-1) Warning
631 Warn when a function parameter is unused
634 Common Var(warn_unused_value) Init(-1) Warning
635 Warn when an expression value is unused
638 Common Var(warn_unused_variable) Init(-1) Warning
639 Warn when a variable is unused
642 Common Var(warn_coverage_mismatch) Init(1) Warning
643 Warn in case profiles in -fprofile-use do not match
655 Common Separate Var(aux_info_file_name)
656 -aux-info <file> Emit declaration information into <file>
659 Common Joined Alias(aux-info)
662 Common Separate RejectDriver Var(aux_base_name)
665 Common Separate RejectDriver
675 -d<letters> Enable dumps from specific passes of the compiler
678 Common Separate Var(dump_base_name)
679 -dumpbase <file> Set the file basename to be used for dumps
682 Common Separate Var(dump_dir_name)
683 -dumpdir <dir> Set the directory name to be used for dumps
695 Driver Joined Separate
697 ; The version of the C++ ABI in use. The following values are allowed:
699 ; 0: The version of the ABI believed most conformant with the C++ ABI
700 ; specification. This ABI may change as bugs are discovered and fixed.
701 ; Therefore, 0 will not necessarily indicate the same ABI in different
704 ; 1: The version of the ABI first used in G++ 3.2.
706 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
708 ; 3: The version of the ABI that fixes the missing underscore
709 ; in template non-type arguments of pointer type.
711 ; 4: The version of the ABI that introduces unambiguous mangling of
714 ; Additional positive integers will be assigned as new versions of
715 ; the ABI become the default version of the ABI.
717 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
720 Common Report Var(align_functions,0) Optimization UInteger
721 Align the start of functions
724 Common RejectNegative Joined UInteger Var(align_functions)
727 Common Report Var(align_jumps,0) Optimization UInteger
728 Align labels which are only reached by jumping
731 Common RejectNegative Joined UInteger Var(align_jumps)
734 Common Report Var(align_labels,0) Optimization UInteger
738 Common RejectNegative Joined UInteger Var(align_labels)
741 Common Report Var(align_loops,0) Optimization UInteger
742 Align the start of loops
745 Common RejectNegative Joined UInteger Var(align_loops)
749 Does nothing. Preserved for backward compatibility.
753 Does nothing. Preserved for backward compatibility.
755 fargument-noalias-global
757 Does nothing. Preserved for backward compatibility.
759 fargument-noalias-anything
761 Does nothing. Preserved for backward compatibility.
763 fasynchronous-unwind-tables
764 Common Report Var(flag_asynchronous_unwind_tables) Optimization
765 Generate unwind tables that are exact at each instruction boundary
768 Common Report Var(flag_auto_inc_dec) Init(1)
769 Generate auto-inc/dec instructions
771 ; -fcheck-bounds causes gcc to generate array bounds checks.
772 ; For C, C++ and ObjC: defaults off.
773 ; For Java: defaults to on.
774 ; For Fortran: defaults to off.
776 Common Report Var(flag_bounds_check)
777 Generate code to check bounds before indexing arrays
780 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
781 Replace add, compare, branch with branch on count register
783 fbranch-probabilities
784 Common Report Var(flag_branch_probabilities) Optimization
785 Use profiling information for branch probabilities
787 fbranch-target-load-optimize
788 Common Report Var(flag_branch_target_load_optimize) Optimization
789 Perform branch target load optimization before prologue / epilogue threading
791 fbranch-target-load-optimize2
792 Common Report Var(flag_branch_target_load_optimize2) Optimization
793 Perform branch target load optimization after prologue / epilogue threading
796 Common Report Var(flag_btr_bb_exclusive) Optimization
797 Restrict target load migration not to re-use registers in any basic block
800 Common Joined RejectNegative Var(common_deferred_options) Defer
801 -fcall-saved-<register> Mark <register> as being preserved across functions
804 Common Joined RejectNegative Var(common_deferred_options) Defer
805 -fcall-used-<register> Mark <register> as being corrupted by function calls
807 ; Nonzero for -fcaller-saves: allocate values in regs that need to
808 ; be saved across function calls, if that produces overall better code.
809 ; Optional now, so people can test it.
811 Common Report Var(flag_caller_saves) Optimization
812 Save registers around function calls
815 Common Report Var(flag_check_data_deps)
816 Compare the results of several data dependence analyzers.
818 fcombine-stack-adjustments
819 Common Report Var(flag_combine_stack_adjustments) Optimization
820 Looks for opportunities to reduce stack adjustments and stack references.
823 Common Report Var(flag_no_common,0) Optimization
824 Do not put uninitialized globals in the common section
828 ; Converted by the driver to -fcompare-debug= options.
831 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
832 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
834 fcompare-debug-second
835 Common Driver RejectNegative
836 Run only the second compilation of -fcompare-debug
839 Common Var(flag_conserve_stack) Optimization
840 Do not perform optimizations increasing noticeably stack usage
843 Common Report Var(flag_cprop_registers) Optimization
844 Perform a register copy-propagation optimization pass
847 Common Report Var(flag_crossjumping) Optimization
848 Perform cross-jumping optimization
851 Common Report Var(flag_cse_follow_jumps) Optimization
852 When running CSE, follow jumps to their targets
856 Does nothing. Preserved for backward compatibility.
859 Common Report Var(flag_cx_limited_range) Optimization
860 Omit range reduction step when performing complex division
863 Common Report Var(flag_cx_fortran_rules) Optimization
864 Complex multiplication and division follow Fortran rules
867 Common Report Var(flag_data_sections) Optimization
868 Place data items into their own section
871 Common Report Var(common_deferred_options) Defer
872 List all available debugging counters with their limits and counts.
875 Common RejectNegative Joined Var(common_deferred_options) Defer
876 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
879 Common Joined RejectNegative Var(common_deferred_options) Defer
880 Map one directory name to another in debug information
882 ; Nonzero for -fdefer-pop: don't pop args after each function call
883 ; instead save them up to pop many calls' args with one insns.
885 Common Report Var(flag_defer_pop) Optimization
886 Defer popping functions args from stack until later
889 Common Report Var(flag_delayed_branch) Optimization
890 Attempt to fill delay slots of branch instructions
892 fdelete-null-pointer-checks
893 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
894 Delete useless null pointer checks
896 fdiagnostics-show-location=
897 Common Joined RejectNegative
898 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
900 fdiagnostics-show-option
901 Common Var(flag_diagnostics_show_option) Init(1)
902 Amend appropriate diagnostic messages with the command line option that controls them
905 Common Joined RejectNegative Var(common_deferred_options) Defer
906 -fdump-<type> Dump various compiler internals to a file
909 Driver RejectNegative
912 Common RejectNegative Joined Var(flag_dump_final_insns)
913 -fdump-final-insns=filename Dump to filename the insns at the end of translation
916 Common RejectNegative Joined Var(flag_dump_go_spec)
917 -fdump-go-spec=filename Write all declarations to file as Go code
920 Common Report Var(flag_dump_noaddr)
921 Suppress output of addresses in debugging dumps
924 Common Report Var(flag_dump_unnumbered)
925 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
927 fdump-unnumbered-links
928 Common Report Var(flag_dump_unnumbered_links)
929 Suppress output of previous and next insn numbers in debugging dumps
932 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
933 Enable CFI tables via GAS assembler directives.
936 Common Report Var(flag_early_inlining) Init(1) Optimization
937 Perform early inlining
939 feliminate-dwarf2-dups
940 Common Report Var(flag_eliminate_dwarf2_dups)
941 Perform DWARF2 duplicate elimination
944 Common Report Var(flag_ipa_sra) Init(0) Optimization
945 Perform interprocedural reduction of aggregates
947 feliminate-unused-debug-symbols
948 Common Report Var(flag_debug_only_used_symbols)
949 Perform unused type elimination in debug info
951 feliminate-unused-debug-types
952 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
953 Perform unused type elimination in debug info
955 femit-class-debug-always
956 Common Report Var(flag_emit_class_debug_always) Init(0)
957 Do not suppress C++ class debug information.
960 Common Report Var(flag_enable_icf_debug)
961 Generate debug information to support Identical Code Folding (ICF)
964 Common Report Var(flag_exceptions) Optimization
965 Enable exception handling
967 fexpensive-optimizations
968 Common Report Var(flag_expensive_optimizations) Optimization
969 Perform a number of minor, expensive optimizations
972 Common Joined RejectNegative
973 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
979 Common Report Var(flag_finite_math_only) Optimization
980 Assume no NaNs or infinities are generated
983 Common Joined RejectNegative Var(common_deferred_options) Defer
984 -ffixed-<register> Mark <register> as being unavailable to the compiler
987 Common Report Var(flag_float_store) Optimization
988 Don't allocate floats and doubles in extended-precision registers
992 Does nothing. Preserved for backward compatibility.
995 Common Report Var(flag_forward_propagate) Optimization
996 Perform a forward propagation pass on RTL
999 Common Joined RejectNegative
1000 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1002 ; Nonzero means don't put addresses of constant functions in registers.
1003 ; Used for compiling the Unix kernel, where strange substitutions are
1004 ; done on the assembly output.
1006 Common Report Var(flag_no_function_cse,0)
1007 Allow function addresses to be held in registers
1010 Common Report Var(flag_function_sections)
1011 Place each function into its own section
1014 Common Report Var(flag_gcse) Optimization
1015 Perform global common subexpression elimination
1018 Common Report Var(flag_gcse_lm) Init(1) Optimization
1019 Perform enhanced load motion during global common subexpression elimination
1022 Common Report Var(flag_gcse_sm) Init(0) Optimization
1023 Perform store motion after global common subexpression elimination
1026 Common Report Var(flag_gcse_las) Init(0) Optimization
1027 Perform redundant load after store elimination in global common subexpression
1031 Common Report Var(flag_gcse_after_reload) Optimization
1032 Perform global common subexpression elimination after register allocation
1035 ; This option is not documented yet as its semantics will change.
1037 Common Report Var(flag_graphite)
1038 Enable in and out of Graphite representation
1041 Common Report Var(flag_graphite_identity) Optimization
1042 Enable Graphite Identity transformation
1044 floop-parallelize-all
1045 Common Report Var(flag_loop_parallelize_all) Optimization
1046 Mark all loops as parallel
1049 Common Report Var(flag_loop_strip_mine) Optimization
1050 Enable Loop Strip Mining transformation
1053 Common Report Var(flag_loop_interchange) Optimization
1054 Enable Loop Interchange transformation
1057 Common Report Var(flag_loop_block) Optimization
1058 Enable Loop Blocking transformation
1061 Common Report Var(flag_loop_flatten) Optimization
1062 Enable Loop Flattening transformation
1064 fstrict-volatile-bitfields
1065 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1066 Force bitfield accesses to match their type width
1068 fguess-branch-probability
1069 Common Report Var(flag_guess_branch_prob) Optimization
1070 Enable guessing of branch probabilities
1072 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1073 ; Generate position-independent code for executables if possible
1074 ; On SVR4 targets, it also controls whether or not to emit a
1075 ; string identifying the compiler.
1077 Common Report Var(flag_no_ident,0)
1078 Process #ident directives
1081 Common Report Var(flag_if_conversion) Optimization
1082 Perform conversion of conditional jumps to branchless equivalents
1085 Common Report Var(flag_if_conversion2) Optimization
1086 Perform conversion of conditional jumps to conditional execution
1088 ftree-loop-if-convert
1089 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1090 Convert conditional jumps in innermost loops to branchless equivalents
1092 ftree-loop-if-convert-stores
1093 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1094 Also if-convert conditional jumps containing memory writes
1096 ; -finhibit-size-directive inhibits output of .size for ELF.
1097 ; This is used only for compiling crtstuff.c,
1098 ; and it may be extended to other effects
1099 ; needed for crtstuff.c on other systems.
1100 finhibit-size-directive
1101 Common Report Var(flag_inhibit_size_directive)
1102 Do not generate .size directives
1105 Common Report Var(flag_indirect_inlining)
1106 Perform indirect inlining
1108 ; Nonzero means that functions declared `inline' will be treated
1109 ; as `static'. Prevents generation of zillions of copies of unused
1110 ; static inline functions; instead, `inlines' are written out
1111 ; only when actually used. Used in conjunction with -g. Also
1112 ; does the right thing with #pragma interface.
1114 Common Report Var(flag_no_inline,0) Init(0)
1115 Pay attention to the \"inline\" keyword
1117 finline-small-functions
1118 Common Report Var(flag_inline_small_functions) Optimization
1119 Integrate simple functions into their callers when code size is known to not growth
1122 Common Report Var(flag_inline_functions) Optimization
1123 Integrate simple functions into their callers
1125 finline-functions-called-once
1126 Common Report Var(flag_inline_functions_called_once) Init(1) Optimization
1127 Integrate functions called once into their callers
1130 Common RejectNegative Joined Alias(finline-limit=)
1133 Common RejectNegative Joined UInteger
1134 -finline-limit=<number> Limit the size of inlined functions to <number>
1136 finstrument-functions
1137 Common Report Var(flag_instrument_function_entry_exit)
1138 Instrument function entry and exit with profiling calls
1140 finstrument-functions-exclude-function-list=
1141 Common RejectNegative Joined
1142 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1144 finstrument-functions-exclude-file-list=
1145 Common RejectNegative Joined
1146 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1149 Common Report Var(flag_ipa_cp) Optimization
1150 Perform Interprocedural constant propagation
1153 Common Report Var(flag_ipa_cp_clone) Optimization
1154 Perform cloning to make Interprocedural constant propagation stronger
1157 Common Report Var(flag_ipa_profile) Init(0) Optimization
1158 Perform interprocedural profile propagation
1161 Common Report Var(flag_ipa_pta) Init(0) Optimization
1162 Perform interprocedural points-to analysis
1165 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1166 Discover pure and const functions
1169 Common Report Var(flag_ipa_reference) Init(0) Optimization
1170 Discover readonly and non addressable static variables
1173 Common Report Var(flag_ipa_matrix_reorg) Optimization
1174 Perform matrix layout flattening and transposing based
1175 on profiling information.
1178 Common Report Var(flag_ipa_struct_reorg)
1179 Perform structure layout optimizations based
1180 on profiling information.
1183 Common Joined RejectNegative
1184 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1187 Common Joined RejectNegative
1188 -fira-region=[one|all|mixed] Set regions for IRA
1191 Common Report Var(flag_ira_loop_pressure)
1192 Use IRA based register pressure calculation
1193 in RTL loop optimizations.
1195 fira-share-save-slots
1196 Common Report Var(flag_ira_share_save_slots) Init(1)
1197 Share slots for saving different hard registers.
1199 fira-share-spill-slots
1200 Common Report Var(flag_ira_share_spill_slots) Init(1)
1201 Share stack slots for spilled pseudo-registers.
1204 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1205 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1208 Common Report Var(flag_ivopts) Init(1) Optimization
1209 Optimize induction variables on trees
1212 Common Var(flag_jump_tables) Init(1) Optimization
1213 Use jump tables for sufficiently large switch statements
1215 fkeep-inline-functions
1216 Common Report Var(flag_keep_inline_functions)
1217 Generate code for functions even if they are fully inlined
1220 Common Report Var(flag_keep_static_consts) Init(1)
1221 Emit static const variables even if they are not used
1224 Common Report Var(flag_leading_underscore) Init(-1)
1225 Give external symbols a leading underscore
1229 Does nothing. Preserved for backward compatibility.
1233 Enable link-time optimization.
1236 Common RejectNegative Joined Var(flag_lto)
1237 Link-time optimization with number of parallel jobs or jobserver.
1240 Common Var(flag_lto_partition_1to1)
1241 Partition functions and vars at linktime based on object files they originate from
1243 flto-partition=balanced
1244 Common Var(flag_lto_partition_balanced)
1245 Partition functions and vars at linktime into approximately same sized buckets
1248 Common Var(flag_lto_partition_none)
1249 Disable partioning and streaming
1251 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1252 flto-compression-level=
1253 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1254 -flto-compression-level=<number> Use zlib compression level <number> for IL
1257 Common Report Var(flag_lto_report) Init(0) Optimization
1258 Report various link-time optimization statistics
1261 Common Report Var(flag_errno_math) Init(1) Optimization
1262 Set errno after built-in math functions
1265 Common Joined RejectNegative UInteger Var(flag_max_errors)
1266 -fmax-errors=<number> Maximum number of errors to report
1269 Common Report Var(mem_report)
1270 Report on permanent memory allocation
1272 ; This will attempt to merge constant section constants, if 1 only
1273 ; string constants and constants from constant pool, if 2 also constant
1275 fmerge-all-constants
1276 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1277 Attempt to merge identical constants and constant variables
1280 Common Report Var(flag_merge_constants,1) Optimization
1281 Attempt to merge identical constants across compilation units
1283 fmerge-debug-strings
1284 Common Report Var(flag_merge_debug_strings) Init(1)
1285 Attempt to merge identical debug strings across compilation units
1288 Common RejectNegative Joined UInteger
1289 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1292 Common Report Var(flag_modulo_sched) Optimization
1293 Perform SMS based modulo scheduling before the first scheduling pass
1295 fmodulo-sched-allow-regmoves
1296 Common Report Var(flag_modulo_sched_allow_regmoves)
1297 Perform SMS based modulo scheduling with register moves allowed
1299 fmove-loop-invariants
1300 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1301 Move loop invariant computations out of loops
1304 Common RejectNegative Report Var(flag_mudflap)
1305 Add mudflap bounds-checking instrumentation for single-threaded program
1308 Common RejectNegative Report Var(flag_mudflap,2)
1309 Add mudflap bounds-checking instrumentation for multi-threaded program
1312 Common RejectNegative Report Var(flag_mudflap_ignore_reads)
1313 Ignore read operations when inserting mudflap instrumentation
1316 Common Var(flag_dce) Init(1) Optimization
1317 Use the RTL dead code elimination pass
1320 Common Var(flag_dse) Init(1) Optimization
1321 Use the RTL dead store elimination pass
1323 freschedule-modulo-scheduled-loops
1324 Common Report Var(flag_resched_modulo_sched) Optimization
1325 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1327 fnon-call-exceptions
1328 Common Report Var(flag_non_call_exceptions) Optimization
1329 Support synchronous non-call exceptions
1332 Common Report Var(flag_omit_frame_pointer) Optimization
1333 When possible do not generate stack frames
1335 foptimize-register-move
1336 Common Report Var(flag_regmove) Optimization
1337 Do the full register move optimization pass
1339 foptimize-sibling-calls
1340 Common Report Var(flag_optimize_sibling_calls) Optimization
1341 Optimize sibling and tail recursive calls
1344 Common Report Var(flag_partial_inlining)
1345 Perform partial inlining
1348 Common Report Var(pre_ipa_mem_report)
1349 Report on memory allocation before interprocedural optimization
1351 fpost-ipa-mem-report
1352 Common Report Var(post_ipa_mem_report)
1353 Report on memory allocation before interprocedural optimization
1356 Common Report Var(flag_pack_struct) Optimization
1357 Pack structure members together without holes
1360 Common RejectNegative Joined UInteger Optimization
1361 -fpack-struct=<number> Set initial maximum structure member alignment
1364 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1365 Return small aggregates in memory, not registers
1368 Common Report Var(flag_peel_loops) Optimization
1369 Perform loop peeling
1372 Common Report Var(flag_no_peephole,0) Optimization
1373 Enable machine specific peephole optimizations
1376 Common Report Var(flag_peephole2) Optimization
1377 Enable an RTL peephole pass before sched2
1380 Common Report Var(flag_pic,2)
1381 Generate position-independent code if possible (large mode)
1384 Common Report Var(flag_pie,2)
1385 Generate position-independent code for executables if possible (large mode)
1388 Common Report Var(flag_pic,1)
1389 Generate position-independent code if possible (small mode)
1392 Common Report Var(flag_pie,1)
1393 Generate position-independent code for executables if possible (small mode)
1396 Common Joined RejectNegative Var(common_deferred_options) Defer
1397 Specify a plugin to load
1400 Common Joined RejectNegative Var(common_deferred_options) Defer
1401 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1403 fpredictive-commoning
1404 Common Report Var(flag_predictive_commoning) Optimization
1405 Run predictive commoning optimization.
1407 fprefetch-loop-arrays
1408 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1409 Generate prefetch instructions, if available, for arrays in loops
1412 Common Report Var(profile_flag)
1413 Enable basic program profiling code
1416 Common Report Var(profile_arc_flag)
1417 Insert arc-based program profiling code
1420 Common Joined RejectNegative Var(profile_data_prefix)
1421 Set the top-level directory for storing the profile data.
1422 The default is 'pwd'.
1425 Common Report Var(flag_profile_correction)
1426 Enable correction of flow inconsistent profile data input
1430 Enable common options for generating profile info for profile feedback directed optimizations
1433 Common Joined RejectNegative
1434 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1437 Common Var(flag_profile_use)
1438 Enable common options for performing profile feedback directed optimizations
1441 Common Joined RejectNegative
1442 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1445 Common Report Var(flag_profile_values)
1446 Insert code to profile values of expressions
1449 Common Var(common_deferred_options) Defer
1452 Common Joined RejectNegative Var(common_deferred_options) Defer
1453 -frandom-seed=<string> Make compile reproducible using <string>
1455 ; This switch causes the command line that was used to create an
1456 ; object file to be recorded into the object file. The exact format
1457 ; of this recording is target and binary file format dependent.
1458 ; It is related to the -fverbose-asm switch, but that switch only
1459 ; records information in the assembler output file as comments, so
1460 ; they never reach the object file.
1461 frecord-gcc-switches
1462 Common Report Var(flag_record_gcc_switches)
1463 Record gcc command line switches in the object file.
1466 Common Report Var(flag_pcc_struct_return,0) Optimization
1467 Return small aggregates in registers
1470 Common Report Var(flag_regmove) Optimization
1471 Enables a register move optimization
1474 Common Report Var(flag_rename_registers) Init(2) Optimization
1475 Perform a register renaming optimization pass
1478 Common Report Var(flag_reorder_blocks) Optimization
1479 Reorder basic blocks to improve code placement
1481 freorder-blocks-and-partition
1482 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1483 Reorder basic blocks and partition into hot and cold sections
1486 Common Report Var(flag_reorder_functions) Optimization
1487 Reorder functions to improve code placement
1489 frerun-cse-after-loop
1490 Common Report Var(flag_rerun_cse_after_loop) Optimization
1491 Add a common subexpression elimination pass after loop optimizations
1495 Does nothing. Preserved for backward compatibility.
1498 Common Report Var(flag_rounding_math) Optimization
1499 Disable optimizations that assume default FP rounding behavior
1502 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1503 Enable scheduling across basic blocks
1506 Common Report Var(flag_sched_pressure) Init(0) Optimization
1507 Enable register pressure sensitive insn scheduling
1510 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1511 Allow speculative motion of non-loads
1514 Common Report Var(flag_schedule_speculative_load) Optimization
1515 Allow speculative motion of some loads
1517 fsched-spec-load-dangerous
1518 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1519 Allow speculative motion of more loads
1522 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1523 -fsched-verbose=<number> Set the verbosity level of the scheduler
1525 fsched2-use-superblocks
1526 Common Report Var(flag_sched2_use_superblocks) Optimization
1527 If scheduling post reload, do superblock scheduling
1531 Does nothing. Preserved for backward compatibility.
1534 Common Report Var(flag_schedule_insns) Optimization
1535 Reschedule instructions before register allocation
1538 Common Report Var(flag_schedule_insns_after_reload) Optimization
1539 Reschedule instructions after register allocation
1541 ; This flag should be on when a target implements non-trivial
1542 ; scheduling hooks, maybe saving some information for its own sake.
1543 ; On IA64, for example, this is used for correct bundling.
1544 fselective-scheduling
1545 Common Report Var(flag_selective_scheduling) Optimization
1546 Schedule instructions using selective scheduling algorithm
1548 fselective-scheduling2
1549 Common Report Var(flag_selective_scheduling2) Optimization
1550 Run selective scheduling after reload
1552 fsel-sched-pipelining
1553 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1554 Perform software pipelining of inner loops during selective scheduling
1556 fsel-sched-pipelining-outer-loops
1557 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1558 Perform software pipelining of outer loops during selective scheduling
1560 fsel-sched-reschedule-pipelined
1561 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1562 Reschedule pipelined regions without pipelining
1564 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1565 ; of stalled insns into the ready list.
1566 fsched-stalled-insns
1567 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1568 Allow premature scheduling of queued insns
1570 fsched-stalled-insns=
1571 Common RejectNegative Joined UInteger
1572 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1574 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1575 ; be examined for a dependency on a stalled insn that is candidate for
1576 ; premature removal from the queue of stalled insns into the ready list (has
1577 ; an effect only if the flag 'sched_stalled_insns' is set).
1578 fsched-stalled-insns-dep
1579 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1580 Set dependence distance checking in premature scheduling of queued insns
1582 fsched-stalled-insns-dep=
1583 Common RejectNegative Joined UInteger
1584 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1586 fsched-group-heuristic
1587 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1588 Enable the group heuristic in the scheduler
1590 fsched-critical-path-heuristic
1591 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1592 Enable the critical path heuristic in the scheduler
1594 fsched-spec-insn-heuristic
1595 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1596 Enable the speculative instruction heuristic in the scheduler
1598 fsched-rank-heuristic
1599 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1600 Enable the rank heuristic in the scheduler
1602 fsched-last-insn-heuristic
1603 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1604 Enable the last instruction heuristic in the scheduler
1606 fsched-dep-count-heuristic
1607 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1608 Enable the dependent count heuristic in the scheduler
1611 Common Report Var(flag_section_anchors) Optimization
1612 Access data in the same section from shared anchor points
1616 Does nothing. Preserved for backward compatibility.
1619 Common Report Var(flag_zee) Init(0)
1620 Eliminate redundant zero extensions on targets that support implicit extensions.
1623 Common Report Var(flag_show_column) Init(1)
1624 Show column numbers in diagnostics, when available. Default on
1627 Common Report Var(flag_signaling_nans) Optimization
1628 Disable optimizations observable by IEEE signaling NaNs
1631 Common Report Var(flag_signed_zeros) Init(1) Optimization
1632 Disable floating point optimizations that ignore the IEEE signedness of zero
1634 fsingle-precision-constant
1635 Common Report Var(flag_single_precision_constant) Optimization
1636 Convert floating point constants to single precision constants
1638 fsplit-ivs-in-unroller
1639 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1640 Split lifetimes of induction variables when loops are unrolled
1643 Common Report Var(flag_split_stack) Init(-1)
1644 Generate discontiguous stack frames
1647 Common Report Var(flag_split_wide_types) Optimization
1648 Split wide types into independent registers
1650 fvariable-expansion-in-unroller
1651 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1652 Apply variable expansion when loops are unrolled
1655 Common Report RejectNegative Joined
1656 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1659 Common Alias(fstack-check=, specific, no)
1660 Insert stack checking code into the program. Same as -fstack-check=specific
1663 Common Var(common_deferred_options) Defer
1665 fstack-limit-register=
1666 Common RejectNegative Joined Var(common_deferred_options) Defer
1667 -fstack-limit-register=<register> Trap if the stack goes past <register>
1669 fstack-limit-symbol=
1670 Common RejectNegative Joined Var(common_deferred_options) Defer
1671 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1674 Common Report Var(flag_stack_protect, 1)
1675 Use propolice as a stack protection method
1677 fstack-protector-all
1678 Common Report RejectNegative Var(flag_stack_protect, 2)
1679 Use a stack protection method for every function
1682 Common RejectNegative Var(flag_stack_usage)
1683 Output stack usage information on a per-function basis
1687 Does nothing. Preserved for backward compatibility.
1689 ; Nonzero if we should do (language-dependent) alias analysis.
1690 ; Typically, this analysis will assume that expressions of certain
1691 ; types do not alias expressions of certain other types. Only used
1692 ; if alias analysis (in general) is enabled.
1694 Common Report Var(flag_strict_aliasing) Optimization
1695 Assume strict aliasing rules apply
1698 Common Report Var(flag_strict_overflow)
1699 Treat signed overflow as undefined
1702 Common Report Var(flag_syntax_only)
1703 Check for syntax errors, then stop
1706 Common Report Var(flag_test_coverage)
1707 Create data files needed by \"gcov\"
1710 Common Report Var(flag_thread_jumps) Optimization
1711 Perform jump threading optimizations
1714 Common Report Var(time_report)
1715 Report the time taken by each compiler pass
1718 Common Joined RejectNegative
1719 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
1722 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1723 Reorder top level functions, variables, and asms
1726 Common Report Var(flag_tracer)
1727 Perform superblock formation via tail duplication
1729 ; Zero means that floating-point math operations cannot generate a
1730 ; (user-visible) trap. This is the case, for example, in nonstop
1731 ; IEEE 754 arithmetic.
1733 Common Report Var(flag_trapping_math) Init(1) Optimization
1734 Assume floating-point operations can trap
1737 Common Report Var(flag_trapv) Optimization
1738 Trap for signed overflow in addition, subtraction and multiplication
1741 Common Report Var(flag_tree_ccp) Optimization
1742 Enable SSA-CCP optimization on trees
1745 Common Report Var(flag_tree_bit_ccp) Optimization
1746 Enable SSA-BIT-CCP optimization on trees
1750 Does nothing. Preserved for backward compatibility.
1753 Common Report Var(flag_tree_ch) Optimization
1754 Enable loop header copying on trees
1757 Common Report Var(flag_tree_copyrename) Optimization
1758 Replace SSA temporaries with better names in copies
1761 Common Report Var(flag_tree_copy_prop) Optimization
1762 Enable copy propagation on trees
1764 ftree-store-copy-prop
1766 Does nothing. Preserved for backward compatibility.
1769 Common Report Var(flag_tree_cselim) Init(2) Optimization
1770 Transform condition stores into unconditional ones
1772 ftree-switch-conversion
1773 Common Report Var(flag_tree_switch_conversion) Optimization
1774 Perform conversions of switch initializations.
1777 Common Report Var(flag_tree_dce) Optimization
1778 Enable SSA dead code elimination optimization on trees
1780 ftree-dominator-opts
1781 Common Report Var(flag_tree_dom) Optimization
1782 Enable dominator optimizations
1785 Common Report Var(flag_tree_dse) Optimization
1786 Enable dead store elimination
1789 Common Report Var(flag_tree_forwprop) Init(1) Optimization
1790 Enable forward propagation on trees
1793 Common Report Var(flag_tree_fre) Optimization
1794 Enable Full Redundancy Elimination (FRE) on trees
1796 ftree-loop-distribution
1797 Common Report Var(flag_tree_loop_distribution) Optimization
1798 Enable loop distribution on trees
1800 ftree-loop-distribute-patterns
1801 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
1802 Enable loop distribution for patterns transformed into a library call
1805 Common Report Var(flag_tree_loop_im) Init(1) Optimization
1806 Enable loop invariant motion on trees
1809 Common Report Var(flag_tree_loop_linear) Optimization
1810 Enable linear loop transforms on trees
1813 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
1814 Create canonical induction variables in loops
1817 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
1818 Enable loop optimizations on tree level
1820 ftree-parallelize-loops=
1821 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
1822 Enable automatic parallelization of loops
1825 Common Report Var(flag_tree_phiprop) Init(1) Optimization
1826 Enable hoisting loads from conditional pointers.
1829 Common Report Var(flag_tree_pre) Optimization
1830 Enable SSA-PRE optimization on trees
1833 Common Report Var(flag_tree_pta) Init(1) Optimization
1834 Perform function-local points-to analysis on trees.
1837 Common Report Var(flag_tree_reassoc) Init(1) Optimization
1838 Enable reassociation on tree level
1842 Does nothing. Preserved for backward compatibility.
1845 Common Report Var(flag_tree_sink) Optimization
1846 Enable SSA code sinking on trees
1849 Common Report Var(flag_tree_sra) Optimization
1850 Perform scalar replacement of aggregates
1853 Common Report Var(flag_tree_ter) Optimization
1854 Replace temporary expressions in the SSA->normal pass
1857 Common Report Var(flag_tree_live_range_split) Optimization
1858 Perform live range splitting during the SSA->normal pass
1861 Common Report Var(flag_tree_vrp) Init(0) Optimization
1862 Perform Value Range Propagation on trees
1865 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
1866 Compile whole compilation unit at a time
1869 Common Report Var(flag_unroll_loops) Optimization
1870 Perform loop unrolling when iteration count is known
1873 Common Report Var(flag_unroll_all_loops) Optimization
1874 Perform loop unrolling for all loops
1876 ; Nonzero means that loop optimizer may assume that the induction variables
1877 ; that control loops do not overflow and that the loops with nontrivial
1878 ; exit condition are not infinite
1879 funsafe-loop-optimizations
1880 Common Report Var(flag_unsafe_loop_optimizations) Optimization
1881 Allow loop optimizations to assume that the loops behave in normal way
1884 Common Report Var(flag_associative_math)
1885 Allow optimization for floating-point arithmetic which may change the
1886 result of the operation due to rounding.
1889 Common Report Var(flag_reciprocal_math)
1890 Same as -fassociative-math for expressions which include division.
1892 ; Nonzero means that unsafe floating-point math optimizations are allowed
1893 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
1894 ; are allowed to assume that their arguments and results are "normal"
1895 ; (e.g., nonnegative for SQRT).
1896 funsafe-math-optimizations
1897 Common Report Var(flag_unsafe_math_optimizations) Optimization
1898 Allow math optimizations that may violate IEEE or ISO standards
1901 Common Report Var(flag_unswitch_loops) Optimization
1902 Perform loop unswitching
1905 Common Report Var(flag_unwind_tables) Optimization
1906 Just generate unwind tables for exception handling
1911 ; Positive if we should track variables, negative if we should run
1912 ; the var-tracking pass only to discard debug annotations, zero if
1913 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
1914 ; will be set according to optimize, debug_info_level and debug_hooks
1915 ; in process_options ().
1917 Common Report Var(flag_var_tracking) Init(2) Optimization
1918 Perform variable tracking
1920 ; Positive if we should track variables at assignments, negative if
1921 ; we should run the var-tracking pass only to discard debug
1922 ; annotations. When flag_var_tracking_assignments ==
1923 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
1924 fvar-tracking-assignments
1925 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
1926 Perform variable tracking by annotating assignments
1928 ; Nonzero if we should toggle flag_var_tracking_assignments after
1929 ; processing options and computing its default. */
1930 fvar-tracking-assignments-toggle
1931 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
1932 Toggle -fvar-tracking-assignments
1934 fvar-tracking-uninit
1935 Common Report Var(flag_var_tracking_uninit) Optimization
1936 Perform variable tracking and also tag variables that are uninitialized
1939 Common Report Var(flag_tree_vectorize) Optimization
1940 Enable loop vectorization on trees
1943 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
1944 Enable basic block vectorization (SLP) on trees
1947 Common Report Var(flag_vect_cost_model) Optimization
1948 Enable use of cost model in vectorization
1950 ftree-vect-loop-version
1951 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
1952 Enable loop versioning when doing loop vectorization on trees
1954 ftree-vectorizer-verbose=
1955 Common RejectNegative Joined
1956 -ftree-vectorizer-verbose=<number> Set the verbosity level of the vectorizer
1959 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
1960 Enable copy propagation of scalar-evolution information.
1962 ; -fverbose-asm causes extra commentary information to be produced in
1963 ; the generated assembly code (to make it more readable). This option
1964 ; is generally only of use to those who actually need to read the
1965 ; generated assembly code (perhaps while debugging the compiler itself).
1966 ; -fno-verbose-asm, the default, causes the extra information
1967 ; to not be added and is useful when comparing two assembler files.
1969 Common Report Var(flag_verbose_asm)
1970 Add extra commentary to assembler output
1973 Common Joined RejectNegative
1974 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
1978 Common Report Var(flag_value_profile_transformations) Optimization
1979 Use expression value profiles in optimizations
1982 Common Report Var(flag_web) Init(2) Optimization
1983 Construct webs and split unrelated uses of single variable
1985 ftree-builtin-call-dce
1986 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
1987 Enable conditional dead code elimination for builtin calls
1990 Common Report Var(flag_whole_program) Init(0) Optimization
1991 Perform whole program optimizations
1994 Common Report Var(flag_wrapv) Optimization
1995 Assume signed arithmetic overflow wraps around
1997 fzero-initialized-in-bss
1998 Common Report Var(flag_zero_initialized_in_bss) Init(1)
1999 Put zero initialized data in the bss section
2002 Common JoinedOrMissing
2003 Generate debug information in default format
2006 Common JoinedOrMissing Negative(gdwarf-)
2007 Generate debug information in COFF format
2010 Common Joined UInteger Var(dwarf_version) Init(2) Negative(gstabs)
2011 Generate debug information in DWARF v2 (or later) format
2014 Common JoinedOrMissing
2015 Generate debug information in default extended format
2018 Common JoinedOrMissing Negative(gstabs+)
2019 Generate debug information in STABS format
2022 Common JoinedOrMissing Negative(gvms)
2023 Generate debug information in extended STABS format
2026 Common RejectNegative Var(dwarf_strict,0) Init(-1)
2027 Emit DWARF additions beyond selected version
2030 Common Report RejectNegative Var(dwarf_strict,1)
2031 Don't emit DWARF additions beyond selected version
2034 Common Report Var(flag_gtoggle)
2035 Toggle debug information generation
2038 Common JoinedOrMissing Negative(gxcoff)
2039 Generate debug information in VMS format
2042 Common JoinedOrMissing Negative(gxcoff+)
2043 Generate debug information in XCOFF format
2046 Common JoinedOrMissing Negative(gcoff)
2047 Generate debug information in extended XCOFF format
2050 Driver Joined Separate
2053 Common Joined Var(plugindir_string) Init(0)
2054 -iplugindir=<dir> Set <dir> to be the default plugin directory
2057 Driver Joined Separate
2059 no-canonical-prefixes
2069 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2070 -o <file> Place output into <file>
2073 Common Var(profile_flag)
2074 Enable function profiling
2077 Driver Var(pass_exit_codes)
2080 Common Var(pedantic)
2081 Issue warnings needed for strict compliance to the standard
2084 Common Var(flag_pedantic_errors)
2085 Like -pedantic but issue them as errors
2091 Driver Var(use_pipes)
2094 Driver JoinedOrMissing Var(print_file_name)
2096 print-libgcc-file-name
2099 print-multi-directory
2100 Driver Var(print_multi_directory)
2103 Driver Var(print_multi_lib)
2105 print-multi-os-directory
2106 Driver Var(print_multi_os_directory)
2109 Driver JoinedOrMissing Var(print_prog_name)
2112 Driver Var(print_search_dirs)
2115 Driver Var(print_sysroot)
2117 print-sysroot-headers-suffix
2118 Driver Var(print_sysroot_headers_suffix)
2121 Common Var(quiet_flag) RejectDriver
2122 Do not display functions compiled or elapsed time
2131 Driver Var(report_times)
2134 Driver JoinedOrMissing
2137 Driver Joined Separate
2141 ; C option, but driver must not handle as "-u ndef".
2144 Common Driver Var(verbose_flag)
2145 Enable verbose output
2148 Common Var(version_flag) RejectDriver
2149 Display the compiler's version
2152 Common Var(inhibit_warnings)
2156 Driver Separate Var(wrapper_string)
2159 Driver Joined Separate
2162 Common RejectNegative Negative(pie)
2163 Create a shared library
2169 Driver Separate Alias(specs=)
2182 ; Documented for Fortran, but always accepted by driver.
2191 Common RejectNegative Negative(shared)
2192 Create a position independent executable
2195 Driver Joined Separate
2197 ; This comment is to ensure we retain the blank line above.