1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003, 2004, 2005, 2006 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 2, 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 COPYING. If not, write to the Free
19 ; Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
22 ; See the GCC internals manual for a description of this file's format.
24 ; Please try to keep this file in ASCII collating order.
28 Display this information
32 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
41 Common Joined Separate UInteger
42 -G<number> Put global and static data smaller than <number> bytes into a special section (on some targets)
45 Common JoinedOrMissing
46 -O<number> Set optimization level to <number>
50 Optimize for space rather than speed
54 This switch is deprecated; use -Wextra instead
57 Common Var(warn_aggregate_return)
58 Warn about returning structures, unions or arrays
61 Common Var(warn_attributes) Init(1)
62 Warn about inappropriate attribute usage
65 Common Var(warn_cast_align)
66 Warn about pointer casts which increase alignment
68 Wdeprecated-declarations
69 Common Var(warn_deprecated_decl) Init(1)
70 Warn about uses of __attribute__((deprecated)) declarations
72 Wdisabled-optimization
73 Common Var(warn_disabled_optimization)
74 Warn when an optimization pass is disabled
77 Common Var(warnings_are_errors)
78 Treat all warnings as errors
82 Treat specified warning as error
86 Print extra (possibly unwanted) warnings
89 Common Var(flag_fatal_errors)
90 Exit on the first error occurred
93 Common Var(warn_inline)
94 Warn when an inlined function cannot be inlined
97 Common RejectNegative Joined UInteger
98 -Wlarger-than-<number> Warn if an object is larger than <number> bytes
101 Common RejectNegative Joined UInteger
102 -Wframe-larger-than-<number> Warn if the frame size of a function is larger than <number> bytes
104 Wunsafe-loop-optimizations
105 Common Var(warn_unsafe_loop_optimizations)
106 Warn if the loop cannot be optimized due to nontrivial assumptions.
109 Common Var(warn_missing_noreturn)
110 Warn about functions which might be candidates for __attribute__((noreturn))
113 Common Var(warn_overflow) Init(1)
114 Warn about overflow in arithmetic expressions
117 Common Var(warn_packed)
118 Warn when the packed attribute has no effect on struct layout
121 Common Var(warn_padded)
122 Warn when padding is required to align structure members
125 Common Var(warn_shadow)
126 Warn when one local variable shadows another
129 Common Var(warn_stack_protect)
130 Warn when not issuing stack smashing protection for some reason
134 Warn about code which might break strict aliasing rules
137 Common Joined UInteger
138 Warn about code which might break strict aliasing rules
142 Warn about optimizations that assume that signed overflow is undefined
145 Common Joined UInteger
146 Warn about optimizations that assume that signed overflow is undefined
149 Common Var(warn_switch)
150 Warn about enumerated switches, with no default, missing a case
153 Common Var(warn_switch_default)
154 Warn about enumerated switches missing a \"default:\" statement
157 Common Var(warn_switch_enum)
158 Warn about all enumerated switches missing a specific case
161 Common Var(warn_system_headers)
162 Do not suppress warnings from system headers
165 Common Var(warn_uninitialized)
166 Warn about uninitialized automatic variables
169 Common Var(warn_notreached)
170 Warn about code that will never be executed
174 Enable all -Wunused- warnings
177 Common Var(warn_unused_function)
178 Warn when a function is unused
181 Common Var(warn_unused_label)
182 Warn when a label is unused
185 Common Var(warn_unused_parameter)
186 Warn when a function parameter is unused
189 Common Var(warn_unused_value)
190 Warn when an expression value is unused
193 Common Var(warn_unused_variable)
194 Warn when a variable is unused
197 Common Var(warn_variable_decl)
198 Warn about variable-sized declarations.
200 Wvolatile-register-var
201 Common Var(warn_register_var)
202 Warn when a register variable is declared volatile
206 -aux-info <file> Emit declaration information into <file>
219 -d<letters> Enable dumps from specific passes of the compiler
223 -dumpbase <file> Set the file basename to be used for dumps
225 ; The version of the C++ ABI in use. The following values are allowed:
227 ; 0: The version of the ABI believed most conformant with the C++ ABI
228 ; specification. This ABI may change as bugs are discovered and fixed.
229 ; Therefore, 0 will not necessarily indicate the same ABI in different
232 ; 1: The version of the ABI first used in G++ 3.2.
234 ; Additional positive integers will be assigned as new versions of
235 ; the ABI become the default version of the ABI.
237 Common Joined UInteger Var(flag_abi_version) Init(2)
240 Common Report Var(align_functions,0)
241 Align the start of functions
244 Common RejectNegative Joined UInteger
247 Common Report Var(align_jumps,0)
248 Align labels which are only reached by jumping
251 Common RejectNegative Joined UInteger
254 Common Report Var(align_labels,0)
258 Common RejectNegative Joined UInteger
261 Common Report Var(align_loops)
262 Align the start of loops
265 Common RejectNegative Joined UInteger
267 ; This flag is only tested if alias checking is enabled.
268 ; 0 if pointer arguments may alias each other. True in C.
269 ; 1 if pointer arguments may not alias each other but may alias
271 ; 2 if pointer arguments may not alias each other and may not
272 ; alias global variables.
273 ; 3 if pointer arguments may not alias anything. True in Fortran.
274 ; Set by the front end.
276 Common Report Var(flag_argument_noalias,0)
277 Specify that arguments may alias each other and globals
280 Common Report Var(flag_argument_noalias,1) VarExists
281 Assume arguments may alias globals but not each other
283 fargument-noalias-global
284 Common Report Var(flag_argument_noalias,2) VarExists
285 Assume arguments alias neither each other nor globals
287 fargument-noalias-anything
288 Common Report Var(flag_argument_noalias,3) VarExists
289 Assume arguments alias no other storage
291 fasynchronous-unwind-tables
292 Common Report Var(flag_asynchronous_unwind_tables)
293 Generate unwind tables that are exact at each instruction boundary
295 ; -fcheck-bounds causes gcc to generate array bounds checks.
296 ; For C, C++ and ObjC: defaults off.
297 ; For Java: defaults to on.
298 ; For Fortran: defaults to off.
300 Common Report Var(flag_bounds_check)
301 Generate code to check bounds before indexing arrays
304 Common Report Var(flag_branch_on_count_reg) Init(1)
305 Replace add, compare, branch with branch on count register
307 fbranch-probabilities
308 Common Report Var(flag_branch_probabilities)
309 Use profiling information for branch probabilities
311 fbranch-target-load-optimize
312 Common Report Var(flag_branch_target_load_optimize)
313 Perform branch target load optimization before prologue / epilogue threading
315 fbranch-target-load-optimize2
316 Common Report Var(flag_branch_target_load_optimize2)
317 Perform branch target load optimization after prologue / epilogue threading
320 Common Report Var(flag_btr_bb_exclusive)
321 Restrict target load migration not to re-use registers in any basic block
324 Common Joined RejectNegative
325 -fcall-saved-<register> Mark <register> as being preserved across functions
328 Common Joined RejectNegative
329 -fcall-used-<register> Mark <register> as being corrupted by function calls
331 ; Nonzero for -fcaller-saves: allocate values in regs that need to
332 ; be saved across function calls, if that produces overall better code.
333 ; Optional now, so people can test it.
335 Common Report Var(flag_caller_saves)
336 Save registers around function calls
339 Common Report Var(flag_no_common,0)
340 Do not put uninitialized globals in the common section
343 Common Report Var(flag_cprop_registers)
344 Perform a register copy-propagation optimization pass
347 Common Report Var(flag_crossjumping)
348 Perform cross-jumping optimization
351 Common Report Var(flag_cse_follow_jumps)
352 When running CSE, follow jumps to their targets
355 Common Report Var(flag_cse_skip_blocks)
356 When running CSE, follow conditional jumps
359 Common Report Var(flag_cx_limited_range)
360 Omit range reduction step when performing complex division
363 Common Report Var(flag_data_sections)
364 Place data items into their own section
366 ; Nonzero for -fdefer-pop: don't pop args after each function call
367 ; instead save them up to pop many calls' args with one insns.
369 Common Report Var(flag_defer_pop)
370 Defer popping functions args from stack until later
373 Common Report Var(flag_delayed_branch)
374 Attempt to fill delay slots of branch instructions
376 fdelete-null-pointer-checks
377 Common Report Var(flag_delete_null_pointer_checks)
378 Delete useless null pointer checks
380 fdiagnostics-show-location=
381 Common Joined RejectNegative
382 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
384 fdiagnostics-show-option
386 Amend appropriate diagnostic messages with the command line option that controls them
389 Common Joined RejectNegative
390 -fdump-<type> Dump various compiler internals to a file
393 Common Report Var(flag_dump_noaddr)
394 Suppress output of addresses in debugging dumps
397 Common Report Var(flag_dump_unnumbered) VarExists
398 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
401 Common Report Var(flag_early_inlining) Init(1)
402 Perform early inlining
404 feliminate-dwarf2-dups
405 Common Report Var(flag_eliminate_dwarf2_dups)
406 Perform DWARF2 duplicate elimination
408 feliminate-unused-debug-symbols
409 Common Report Var(flag_debug_only_used_symbols)
410 Perform unused type elimination in debug info
412 feliminate-unused-debug-types
413 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
414 Perform unused type elimination in debug info
416 femit-class-debug-always
417 Common Report Var(flag_emit_class_debug_always) Init(1)
418 Do not suppress C++ class debug information.
421 Common Report Var(flag_exceptions)
422 Enable exception handling
424 fexpensive-optimizations
425 Common Report Var(flag_expensive_optimizations)
426 Perform a number of minor, expensive optimizations
432 Common Report Var(flag_finite_math_only)
433 Assume no NaNs or infinities are generated
436 Common Joined RejectNegative
437 -ffixed-<register> Mark <register> as being unavailable to the compiler
440 Common Report Var(flag_float_store)
441 Don't allocate floats and doubles in extended-precision registers
443 ; Nonzero for -fforce-addr: load memory address into a register before
444 ; reference to memory. This makes better cse but slower compilation.
446 Common Report Var(flag_force_addr)
447 Copy memory address constants into registers before use
449 ; Nonzero for -fforce-mem: load memory value into a register
450 ; before arithmetic on it. This makes better cse but slower compilation.
452 Common Report Var(flag_force_mem)
453 Copy memory operands into registers before use
455 ; Nonzero means don't put addresses of constant functions in registers.
456 ; Used for compiling the Unix kernel, where strange substitutions are
457 ; done on the assembly output.
459 Common Report Var(flag_no_function_cse,0)
460 Allow function addresses to be held in registers
463 Common Report Var(flag_function_sections)
464 Place each function into its own section
467 Common Report Var(flag_gcse)
468 Perform global common subexpression elimination
471 Common Report Var(flag_gcse_lm) Init(1)
472 Perform enhanced load motion during global common subexpression elimination
475 Common Report Var(flag_gcse_sm) Init(0)
476 Perform store motion after global common subexpression elimination
479 Common Report Var(flag_gcse_las) Init(0)
480 Perform redundant load after store elimination in global common subexpression
484 Common Report Var(flag_gcse_after_reload)
485 Perform global common subexpression elimination after register allocation
488 fguess-branch-probability
489 Common Report Var(flag_guess_branch_prob)
490 Enable guessing of branch probabilities
492 ; Nonzero means ignore `#ident' directives. 0 means handle them.
493 ; Generate position-independent code for executables if possible
494 ; On SVR4 targets, it also controls whether or not to emit a
495 ; string identifying the compiler.
497 Common Report Var(flag_no_ident,0)
498 Process #ident directives
501 Common Report Var(flag_if_conversion)
502 Perform conversion of conditional jumps to branchless equivalents
505 Common Report Var(flag_if_conversion2)
506 Perform conversion of conditional jumps to conditional execution
508 ; -finhibit-size-directive inhibits output of .size for ELF.
509 ; This is used only for compiling crtstuff.c,
510 ; and it may be extended to other effects
511 ; needed for crtstuff.c on other systems.
512 finhibit-size-directive
513 Common Report Var(flag_inhibit_size_directive)
514 Do not generate .size directives
516 ; Nonzero means that functions declared `inline' will be treated
517 ; as `static'. Prevents generation of zillions of copies of unused
518 ; static inline functions; instead, `inlines' are written out
519 ; only when actually used. Used in conjunction with -g. Also
520 ; does the right thing with #pragma interface.
522 Common Report Var(flag_no_inline,0) Init(2)
523 Pay attention to the \"inline\" keyword
526 Common Report Var(flag_inline_functions)
527 Integrate simple functions into their callers
529 finline-functions-called-once
530 Common Report Var(flag_inline_functions_called_once) Init(1)
531 Integrate functions called once into their callers
534 Common RejectNegative Joined UInteger
537 Common RejectNegative Joined UInteger
538 -finline-limit=<number> Limit the size of inlined functions to <number>
540 finstrument-functions
541 Common Report Var(flag_instrument_function_entry_exit)
542 Instrument function entry and exit with profiling calls
544 finstrument-functions-exclude-function-list=
545 Common RejectNegative Joined
546 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
548 finstrument-functions-exclude-file-list=
549 Common RejectNegative Joined
550 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
553 Common Report Var(flag_ipa_cp)
554 Perform Interprocedural constant propagation
557 Common Report Var(flag_ipa_pure_const) Init(0)
558 Discover pure and const functions
561 Common Report Var(flag_ipa_pta) Init(0)
562 Perform interprocedural points-to analysis
565 Common Report Var(flag_ipa_reference) Init(0)
566 Discover readonly and non addressable static variables
569 Common Report Var(flag_ipa_type_escape) Init(0)
570 Type based escape and alias analysis
573 Common Report Var(flag_ivopts) Init(1)
574 Optimize induction variables on trees
577 Common Var(flag_jump_tables) Init(1)
578 Use jump tables for sufficiently large switch statements
580 fkeep-inline-functions
581 Common Report Var(flag_keep_inline_functions)
582 Generate code for functions even if they are fully inlined
585 Common Report Var(flag_keep_static_consts) Init(1)
586 Emit static const variables even if they are not used
589 Common Report Var(flag_leading_underscore) Init(-1)
590 Give external symbols a leading underscore
594 Does nothing. Preserved for backward compatibility.
597 Common Report Var(flag_errno_math) Init(0)
598 Set errno after built-in math functions
601 Common Report Var(mem_report)
602 Report on permanent memory allocation
604 ; This will attempt to merge constant section constants, if 1 only
605 ; string constants and constants from constant pool, if 2 also constant
608 Common Report Var(flag_merge_constants,2) Init(1)
609 Attempt to merge identical constants and constant variables
612 Common Report Var(flag_merge_constants,1) VarExists
613 Attempt to merge identical constants across compilation units
616 Common RejectNegative Joined UInteger
617 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
620 Common Report Var(flag_modulo_sched)
621 Perform SMS based modulo scheduling before the first scheduling pass
623 fmove-loop-invariants
624 Common Report Var(flag_move_loop_invariants) Init(1)
625 Move loop invariant computations out of loops
628 Common RejectNegative Report Var(flag_mudflap)
629 Add mudflap bounds-checking instrumentation for single-threaded program
632 Common RejectNegative Report VarExists Var(flag_mudflap,2)
633 Add mudflap bounds-checking instrumentation for multi-threaded program
636 Common RejectNegative Report Var(flag_mudflap_ignore_reads)
637 Ignore read operations when inserting mudflap instrumentation
639 freschedule-modulo-scheduled-loops
640 Common Report Var(flag_resched_modulo_sched)
641 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
644 Common Report Var(flag_non_call_exceptions)
645 Support synchronous non-call exceptions
648 Common Report Var(flag_omit_frame_pointer)
649 When possible do not generate stack frames
651 foptimize-register-move
652 Common Report Var(flag_regmove)
653 Do the full register move optimization pass
655 foptimize-sibling-calls
656 Common Report Var(flag_optimize_sibling_calls)
657 Optimize sibling and tail recursive calls
660 Common Report Var(flag_pack_struct)
661 Pack structure members together without holes
664 Common RejectNegative Joined UInteger
665 -fpack-struct=<number> Set initial maximum structure member alignment
668 Common Report Var(flag_pcc_struct_return,1) VarExists
669 Return small aggregates in memory, not registers
672 Common Report Var(flag_peel_loops)
676 Common Report Var(flag_no_peephole,0)
677 Enable machine specific peephole optimizations
680 Common Report Var(flag_peephole2)
681 Enable an RTL peephole pass before sched2
684 Common Report Var(flag_pic,2)
685 Generate position-independent code if possible (large mode)
688 Common Report Var(flag_pie,2)
689 Generate position-independent code for executables if possible (large mode)
692 Common Report Var(flag_pic,1) VarExists
693 Generate position-independent code if possible (small mode)
696 Common Report Var(flag_pie,1) VarExists
697 Generate position-independent code for executables if possible (small mode)
699 fprefetch-loop-arrays
700 Common Report Var(flag_prefetch_loop_arrays)
701 Generate prefetch instructions, if available, for arrays in loops
704 Common Report Var(profile_flag)
705 Enable basic program profiling code
708 Common Report Var(profile_arc_flag)
709 Insert arc-based program profiling code
713 Enable common options for generating profile info for profile feedback directed optimizations
717 Enable common options for performing profile feedback directed optimizations
720 Common Report Var(flag_profile_values)
721 Insert code to profile values of expressions
727 Common Joined RejectNegative
728 -frandom-seed=<string> Make compile reproducible using <string>
731 Common Report Var(flag_pcc_struct_return,0) VarExists
732 Return small aggregates in registers
735 Common Report Var(flag_regmove)
736 Enables a register move optimization
739 Common Report Var(flag_rename_registers) Init(2)
740 Perform a register renaming optimization pass
743 Common Report Var(flag_reorder_blocks)
744 Reorder basic blocks to improve code placement
746 freorder-blocks-and-partition
747 Common Report Var(flag_reorder_blocks_and_partition)
748 Reorder basic blocks and partition into hot and cold sections
751 Common Report Var(flag_reorder_functions)
752 Reorder functions to improve code placement
754 frerun-cse-after-loop
755 Common Report Var(flag_rerun_cse_after_loop) Init(2)
756 Add a common subexpression elimination pass after loop optimizations
760 Does nothing. Preserved for backward compatibility.
763 Common Report Var(flag_rounding_math)
764 Disable optimizations that assume default FP rounding behavior
767 Common Report Var(flag_schedule_interblock) Init(1)
768 Enable scheduling across basic blocks
771 Common Report Var(flag_schedule_speculative) Init(1)
772 Allow speculative motion of non-loads
775 Common Report Var(flag_schedule_speculative_load)
776 Allow speculative motion of some loads
778 fsched-spec-load-dangerous
779 Common Report Var(flag_schedule_speculative_load_dangerous)
780 Allow speculative motion of more loads
783 Common RejectNegative Joined
784 -fsched-verbose=<number> Set the verbosity level of the scheduler
786 fsched2-use-superblocks
787 Common Report Var(flag_sched2_use_superblocks)
788 If scheduling post reload, do superblock scheduling
791 Common Report Var(flag_sched2_use_traces)
792 If scheduling post reload, do trace scheduling
795 Common Report Var(flag_schedule_insns)
796 Reschedule instructions before register allocation
799 Common Report Var(flag_schedule_insns_after_reload)
800 Reschedule instructions after register allocation
802 ; sched_stalled_insns means that insns can be moved prematurely from the queue
803 ; of stalled insns into the ready list.
805 Common Report Var(flag_sched_stalled_insns)
806 Allow premature scheduling of queued insns
808 fsched-stalled-insns=
809 Common RejectNegative Joined UInteger
810 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
812 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
813 ; be examined for a dependency on a stalled insn that is candidate for
814 ; premature removal from the queue of stalled insns into the ready list (has
815 ; an effect only if the flag 'sched_stalled_insns' is set).
816 fsched-stalled-insns-dep
817 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1)
818 Set dependence distance checking in premature scheduling of queued insns
820 fsched-stalled-insns-dep=
821 Common RejectNegative Joined UInteger
822 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
825 Common Report Var(flag_section_anchors)
826 Access data in the same section from shared anchor points
828 frtl-abstract-sequences
829 Common Report Var(flag_rtl_seqabstr)
830 Perform sequence abstraction optimization on RTL
833 Common Report Var(flag_see) Init(0)
834 Eliminate redundant sign extensions using LCM.
837 Common C ObjC C++ ObjC++ Report Var(flag_show_column) Init(1)
838 Show column numbers in diagnostics, when available. Default on
841 Common Report Var(flag_signaling_nans)
842 Disable optimizations observable by IEEE signaling NaNs
844 fsingle-precision-constant
845 Common Report Var(flag_single_precision_constant)
846 Convert floating point constants to single precision constants
848 fsplit-ivs-in-unroller
849 Common Report Var(flag_split_ivs_in_unroller) Init(1)
850 Split lifetimes of induction variables when loops are unrolled
852 fvariable-expansion-in-unroller
853 Common Report Var(flag_variable_expansion_in_unroller)
854 Apply variable expansion when loops are unrolled
856 ; Emit code to probe the stack, to help detect stack overflow; also
857 ; may cause large objects to be allocated dynamically.
859 Common Report Var(flag_stack_check)
860 Insert stack checking code into the program
865 fstack-limit-register=
866 Common RejectNegative Joined
867 -fstack-limit-register=<register> Trap if the stack goes past <register>
870 Common RejectNegative Joined
871 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
874 Common Report Var(flag_stack_protect, 1)
875 Use propolice as a stack protection method
878 Common Report RejectNegative Var(flag_stack_protect, 2) VarExists
879 Use a stack protection method for every function
881 fstack-protector-strong
882 Common Report RejectNegative Var(flag_stack_protect, 3)
883 Use a smart stack protection method for certain functions
887 Does nothing. Preserved for backward compatibility.
889 ; Nonzero if we should do (language-dependent) alias analysis.
890 ; Typically, this analysis will assume that expressions of certain
891 ; types do not alias expressions of certain other types. Only used
892 ; if alias analysis (in general) is enabled.
894 Common Report Var(flag_strict_aliasing)
895 Assume strict aliasing rules apply
898 Common Report Var(flag_strict_overflow)
899 Treat signed overflow as undefined
902 Common Report Var(flag_syntax_only)
903 Check for syntax errors, then stop
906 Common Report Var(flag_test_coverage)
907 Create data files needed by \"gcov\"
910 Common Report Var(flag_thread_jumps)
911 Perform jump threading optimizations
914 Common Report Var(time_report)
915 Report the time taken by each compiler pass
918 Common Joined RejectNegative
919 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
922 Common Report Var(flag_toplevel_reorder) Init(1)
923 Reorder top level functions, variables, and asms
926 Common Report Var(flag_tracer)
927 Perform superblock formation via tail duplication
929 ; Zero means that floating-point math operations cannot generate a
930 ; (user-visible) trap. This is the case, for example, in nonstop
931 ; IEEE 754 arithmetic.
933 Common Report Var(flag_trapping_math) Init(1)
934 Assume floating-point operations can trap
937 Common Report Var(flag_trapv)
938 Trap for signed overflow in addition, subtraction and multiplication
941 Common Report Var(flag_tree_ccp)
942 Enable SSA-CCP optimization on trees
945 Common Report Var(flag_tree_store_ccp)
946 Enable SSA-CCP optimization for stores and loads
949 Common Report Var(flag_tree_ch)
950 Enable loop header copying on trees
953 Common Report Var(flag_tree_combine_temps)
954 Coalesce memory temporaries in the SSA->normal pass
957 Common Report Var(flag_tree_copyrename)
958 Replace SSA temporaries with better names in copies
961 Common Report Var(flag_tree_copy_prop)
962 Enable copy propagation on trees
964 ftree-store-copy-prop
965 Common Report Var(flag_tree_store_copy_prop)
966 Enable copy propagation for stores and loads
969 Common Report Var(flag_tree_dce)
970 Enable SSA dead code elimination optimization on trees
973 Common Report Var(flag_tree_dom)
974 Enable dominator optimizations
977 Common Report Var(flag_tree_dse)
978 Enable dead store elimination
981 Common Report Var(flag_tree_fre)
982 Enable Full Redundancy Elimination (FRE) on trees
985 Common Report Var(flag_tree_loop_im) Init(1)
986 Enable loop invariant motion on trees
989 Common Report Var(flag_tree_loop_linear)
990 Enable linear loop transforms on trees
993 Common Report Var(flag_tree_loop_ivcanon) Init(1)
994 Create canonical induction variables in loops
997 Common Report Var(flag_tree_loop_optimize) Init(1)
998 Enable loop optimizations on tree level
1001 Common Report Var(flag_tree_pre)
1002 Enable SSA-PRE optimization on trees
1005 Common Report Var(flag_tree_salias)
1006 Perform structural alias analysis
1009 Common Report Var(flag_tree_sink)
1010 Enable SSA code sinking on trees
1013 Common Report Var(flag_tree_sra)
1014 Perform scalar replacement of aggregates
1017 Common Report Var(flag_tree_ter)
1018 Replace temporary expressions in the SSA->normal pass
1021 Common Report Var(flag_tree_live_range_split)
1022 Perform live range splitting during the SSA->normal pass
1025 Common Report Var(flag_tree_vrp) Init(0)
1026 Perform Value Range Propagation on trees
1029 Common Report Var(flag_unit_at_a_time)
1030 Compile whole compilation unit at a time
1033 Common Report Var(flag_unroll_loops)
1034 Perform loop unrolling when iteration count is known
1037 Common Report Var(flag_unroll_all_loops)
1038 Perform loop unrolling for all loops
1040 ; Nonzero means that loop optimizer may assume that the induction variables
1041 ; that control loops do not overflow and that the loops with nontrivial
1042 ; exit condition are not infinite
1043 funsafe-loop-optimizations
1044 Common Report Var(flag_unsafe_loop_optimizations)
1045 Allow loop optimizations to assume that the loops behave in normal way
1047 ; Nonzero means that unsafe floating-point math optimizations are allowed
1048 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
1049 ; are allowed to assume that their arguments and results are "normal"
1050 ; (e.g., nonnegative for SQRT).
1051 funsafe-math-optimizations
1052 Common Report Var(flag_unsafe_math_optimizations)
1053 Allow math optimizations that may violate IEEE or ISO standards
1056 Common Report Var(flag_unswitch_loops)
1057 Perform loop unswitching
1060 Common Report Var(flag_unwind_tables)
1061 Just generate unwind tables for exception handling
1064 Common Report Var(flag_var_tracking) VarExists
1065 Perform variable tracking
1068 Common Report Var(flag_tree_vectorize)
1069 Enable loop vectorization on trees
1071 ftree-vect-loop-version
1072 Common Report Var(flag_tree_vect_loop_version) Init(1)
1073 Enable loop versioning when doing loop vectorization on trees
1075 ftree-vectorizer-verbose=
1076 Common RejectNegative Joined
1077 -ftree-vectorizer-verbose=<number> Set the verbosity level of the vectorizer
1079 ; -fverbose-asm causes extra commentary information to be produced in
1080 ; the generated assembly code (to make it more readable). This option
1081 ; is generally only of use to those who actually need to read the
1082 ; generated assembly code (perhaps while debugging the compiler itself).
1083 ; -fno-verbose-asm, the default, causes the extra information
1084 ; to not be added and is useful when comparing two assembler files.
1086 Common Report Var(flag_verbose_asm)
1087 Add extra commentary to assembler output
1090 Common Joined RejectNegative
1091 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
1095 Common Report Var(flag_value_profile_transformations)
1096 Use expression value profiles in optimizations
1099 Common Report Var(flag_web) Init(2)
1100 Construct webs and split unrelated uses of single variable
1103 Common Report Var(flag_whole_program) Init(0)
1104 Perform whole program optimizations
1107 Common Report Var(flag_wrapv)
1108 Assume signed arithmetic overflow wraps around
1110 fzero-initialized-in-bss
1111 Common Report Var(flag_zero_initialized_in_bss) Init(1)
1112 Put zero initialized data in the bss section
1115 Common JoinedOrMissing
1116 Generate debug information in default format
1119 Common JoinedOrMissing Negative(gdwarf-2)
1120 Generate debug information in COFF format
1123 Common JoinedOrMissing Negative(gstabs)
1124 Generate debug information in DWARF v2 format
1127 Common JoinedOrMissing
1128 Generate debug information in default extended format
1131 Common JoinedOrMissing Negative(gstabs+)
1132 Generate debug information in STABS format
1135 Common JoinedOrMissing Negative(gvms)
1136 Generate debug information in extended STABS format
1139 Common JoinedOrMissing Negative(gxcoff)
1140 Generate debug information in VMS format
1143 Common JoinedOrMissing Negative(gxcoff+)
1144 Generate debug information in XCOFF format
1147 Common JoinedOrMissing Negative(gcoff)
1148 Generate debug information in extended XCOFF format
1151 Common Joined Separate
1152 -o <file> Place output into <file>
1155 Common Var(profile_flag)
1156 Enable function profiling
1159 Common Var(pedantic)
1160 Issue warnings needed for strict compliance to the standard
1164 Like -pedantic but issue them as errors
1167 Common Var(quiet_flag)
1168 Do not display functions compiled or elapsed time
1171 Common Var(version_flag)
1172 Display the compiler's version
1175 Common Var(inhibit_warnings)
1178 ; This comment is to ensure we retain the blank line above.