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
100 Wunsafe-loop-optimizations
101 Common Var(warn_unsafe_loop_optimizations)
102 Warn if the loop cannot be optimized due to nontrivial assumptions.
105 Common Var(warn_missing_noreturn)
106 Warn about functions which might be candidates for __attribute__((noreturn))
109 Common Var(warn_overflow) Init(1)
110 Warn about overflow in arithmetic expressions
113 Common Var(warn_packed)
114 Warn when the packed attribute has no effect on struct layout
117 Common Var(warn_padded)
118 Warn when padding is required to align structure members
121 Common Var(warn_shadow)
122 Warn when one local variable shadows another
125 Common Var(warn_stack_protect)
126 Warn when not issuing stack smashing protection for some reason
130 Warn about code which might break strict aliasing rules
133 Common Joined UInteger
134 Warn about code which might break strict aliasing rules
138 Warn about optimizations that assume that signed overflow is undefined
141 Common Joined UInteger
142 Warn about optimizations that assume that signed overflow is undefined
145 Common Var(warn_switch)
146 Warn about enumerated switches, with no default, missing a case
149 Common Var(warn_switch_default)
150 Warn about enumerated switches missing a \"default:\" statement
153 Common Var(warn_switch_enum)
154 Warn about all enumerated switches missing a specific case
157 Common Var(warn_system_headers)
158 Do not suppress warnings from system headers
161 Common Var(warn_uninitialized)
162 Warn about uninitialized automatic variables
165 Common Var(warn_notreached)
166 Warn about code that will never be executed
170 Enable all -Wunused- warnings
173 Common Var(warn_unused_function)
174 Warn when a function is unused
177 Common Var(warn_unused_label)
178 Warn when a label is unused
181 Common Var(warn_unused_parameter)
182 Warn when a function parameter is unused
185 Common Var(warn_unused_value)
186 Warn when an expression value is unused
189 Common Var(warn_unused_variable)
190 Warn when a variable is unused
193 Common Var(warn_variable_decl)
194 Warn about variable-sized declarations.
196 Wvolatile-register-var
197 Common Var(warn_register_var)
198 Warn when a register variable is declared volatile
202 -aux-info <file> Emit declaration information into <file>
215 -d<letters> Enable dumps from specific passes of the compiler
219 -dumpbase <file> Set the file basename to be used for dumps
221 ; The version of the C++ ABI in use. The following values are allowed:
223 ; 0: The version of the ABI believed most conformant with the C++ ABI
224 ; specification. This ABI may change as bugs are discovered and fixed.
225 ; Therefore, 0 will not necessarily indicate the same ABI in different
228 ; 1: The version of the ABI first used in G++ 3.2.
230 ; Additional positive integers will be assigned as new versions of
231 ; the ABI become the default version of the ABI.
233 Common Joined UInteger Var(flag_abi_version) Init(2)
236 Common Report Var(align_functions,0)
237 Align the start of functions
240 Common RejectNegative Joined UInteger
243 Common Report Var(align_jumps,0)
244 Align labels which are only reached by jumping
247 Common RejectNegative Joined UInteger
250 Common Report Var(align_labels,0)
254 Common RejectNegative Joined UInteger
257 Common Report Var(align_loops)
258 Align the start of loops
261 Common RejectNegative Joined UInteger
263 ; This flag is only tested if alias checking is enabled.
264 ; 0 if pointer arguments may alias each other. True in C.
265 ; 1 if pointer arguments may not alias each other but may alias
267 ; 2 if pointer arguments may not alias each other and may not
268 ; alias global variables.
269 ; 3 if pointer arguments may not alias anything. True in Fortran.
270 ; Set by the front end.
272 Common Report Var(flag_argument_noalias,0)
273 Specify that arguments may alias each other and globals
276 Common Report Var(flag_argument_noalias,1) VarExists
277 Assume arguments may alias globals but not each other
279 fargument-noalias-global
280 Common Report Var(flag_argument_noalias,2) VarExists
281 Assume arguments alias neither each other nor globals
283 fargument-noalias-anything
284 Common Report Var(flag_argument_noalias,3) VarExists
285 Assume arguments alias no other storage
287 fasynchronous-unwind-tables
288 Common Report Var(flag_asynchronous_unwind_tables)
289 Generate unwind tables that are exact at each instruction boundary
291 ; -fcheck-bounds causes gcc to generate array bounds checks.
292 ; For C, C++ and ObjC: defaults off.
293 ; For Java: defaults to on.
294 ; For Fortran: defaults to off.
296 Common Report Var(flag_bounds_check)
297 Generate code to check bounds before indexing arrays
300 Common Report Var(flag_branch_on_count_reg) Init(1)
301 Replace add, compare, branch with branch on count register
303 fbranch-probabilities
304 Common Report Var(flag_branch_probabilities)
305 Use profiling information for branch probabilities
307 fbranch-target-load-optimize
308 Common Report Var(flag_branch_target_load_optimize)
309 Perform branch target load optimization before prologue / epilogue threading
311 fbranch-target-load-optimize2
312 Common Report Var(flag_branch_target_load_optimize2)
313 Perform branch target load optimization after prologue / epilogue threading
316 Common Report Var(flag_btr_bb_exclusive)
317 Restrict target load migration not to re-use registers in any basic block
320 Common Joined RejectNegative
321 -fcall-saved-<register> Mark <register> as being preserved across functions
324 Common Joined RejectNegative
325 -fcall-used-<register> Mark <register> as being corrupted by function calls
327 ; Nonzero for -fcaller-saves: allocate values in regs that need to
328 ; be saved across function calls, if that produces overall better code.
329 ; Optional now, so people can test it.
331 Common Report Var(flag_caller_saves)
332 Save registers around function calls
335 Common Report Var(flag_no_common,0)
336 Do not put uninitialized globals in the common section
339 Common Report Var(flag_cprop_registers)
340 Perform a register copy-propagation optimization pass
343 Common Report Var(flag_crossjumping)
344 Perform cross-jumping optimization
347 Common Report Var(flag_cse_follow_jumps)
348 When running CSE, follow jumps to their targets
351 Common Report Var(flag_cse_skip_blocks)
352 When running CSE, follow conditional jumps
355 Common Report Var(flag_cx_limited_range)
356 Omit range reduction step when performing complex division
359 Common Report Var(flag_data_sections)
360 Place data items into their own section
362 ; Nonzero for -fdefer-pop: don't pop args after each function call
363 ; instead save them up to pop many calls' args with one insns.
365 Common Report Var(flag_defer_pop)
366 Defer popping functions args from stack until later
369 Common Report Var(flag_delayed_branch)
370 Attempt to fill delay slots of branch instructions
372 fdelete-null-pointer-checks
373 Common Report Var(flag_delete_null_pointer_checks)
374 Delete useless null pointer checks
376 fdiagnostics-show-location=
377 Common Joined RejectNegative
378 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
380 fdiagnostics-show-option
382 Amend appropriate diagnostic messages with the command line option that controls them
385 Common Joined RejectNegative
386 -fdump-<type> Dump various compiler internals to a file
389 Common Report Var(flag_dump_noaddr)
390 Suppress output of addresses in debugging dumps
393 Common Report Var(flag_dump_unnumbered) VarExists
394 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
397 Common Report Var(flag_early_inlining) Init(1)
398 Perform early inlining
400 feliminate-dwarf2-dups
401 Common Report Var(flag_eliminate_dwarf2_dups)
402 Perform DWARF2 duplicate elimination
404 feliminate-unused-debug-symbols
405 Common Report Var(flag_debug_only_used_symbols)
406 Perform unused type elimination in debug info
408 feliminate-unused-debug-types
409 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
410 Perform unused type elimination in debug info
412 femit-class-debug-always
413 Common Report Var(flag_emit_class_debug_always) Init(1)
414 Do not suppress C++ class debug information.
417 Common Report Var(flag_exceptions)
418 Enable exception handling
420 fexpensive-optimizations
421 Common Report Var(flag_expensive_optimizations)
422 Perform a number of minor, expensive optimizations
428 Common Report Var(flag_finite_math_only)
429 Assume no NaNs or infinities are generated
432 Common Joined RejectNegative
433 -ffixed-<register> Mark <register> as being unavailable to the compiler
436 Common Report Var(flag_float_store)
437 Don't allocate floats and doubles in extended-precision registers
439 ; Nonzero for -fforce-addr: load memory address into a register before
440 ; reference to memory. This makes better cse but slower compilation.
442 Common Report Var(flag_force_addr)
443 Copy memory address constants into registers before use
445 ; Nonzero for -fforce-mem: load memory value into a register
446 ; before arithmetic on it. This makes better cse but slower compilation.
448 Common Report Var(flag_force_mem)
449 Copy memory operands into registers before use
451 ; Nonzero means don't put addresses of constant functions in registers.
452 ; Used for compiling the Unix kernel, where strange substitutions are
453 ; done on the assembly output.
455 Common Report Var(flag_no_function_cse,0)
456 Allow function addresses to be held in registers
459 Common Report Var(flag_function_sections)
460 Place each function into its own section
463 Common Report Var(flag_gcse)
464 Perform global common subexpression elimination
467 Common Report Var(flag_gcse_lm) Init(1)
468 Perform enhanced load motion during global common subexpression elimination
471 Common Report Var(flag_gcse_sm) Init(0)
472 Perform store motion after global common subexpression elimination
475 Common Report Var(flag_gcse_las) Init(0)
476 Perform redundant load after store elimination in global common subexpression
480 Common Report Var(flag_gcse_after_reload)
481 Perform global common subexpression elimination after register allocation
484 fguess-branch-probability
485 Common Report Var(flag_guess_branch_prob)
486 Enable guessing of branch probabilities
488 ; Nonzero means ignore `#ident' directives. 0 means handle them.
489 ; Generate position-independent code for executables if possible
490 ; On SVR4 targets, it also controls whether or not to emit a
491 ; string identifying the compiler.
493 Common Report Var(flag_no_ident,0)
494 Process #ident directives
497 Common Report Var(flag_if_conversion)
498 Perform conversion of conditional jumps to branchless equivalents
501 Common Report Var(flag_if_conversion2)
502 Perform conversion of conditional jumps to conditional execution
504 ; -finhibit-size-directive inhibits output of .size for ELF.
505 ; This is used only for compiling crtstuff.c,
506 ; and it may be extended to other effects
507 ; needed for crtstuff.c on other systems.
508 finhibit-size-directive
509 Common Report Var(flag_inhibit_size_directive)
510 Do not generate .size directives
512 ; Nonzero means that functions declared `inline' will be treated
513 ; as `static'. Prevents generation of zillions of copies of unused
514 ; static inline functions; instead, `inlines' are written out
515 ; only when actually used. Used in conjunction with -g. Also
516 ; does the right thing with #pragma interface.
518 Common Report Var(flag_no_inline,0) Init(2)
519 Pay attention to the \"inline\" keyword
522 Common Report Var(flag_inline_functions)
523 Integrate simple functions into their callers
525 finline-functions-called-once
526 Common Report Var(flag_inline_functions_called_once) Init(1)
527 Integrate functions called once into their callers
530 Common RejectNegative Joined UInteger
533 Common RejectNegative Joined UInteger
534 -finline-limit=<number> Limit the size of inlined functions to <number>
536 finstrument-functions
537 Common Report Var(flag_instrument_function_entry_exit)
538 Instrument function entry and exit with profiling calls
541 Common Report Var(flag_ipa_cp)
542 Perform Interprocedural constant propagation
545 Common Report Var(flag_ipa_pure_const) Init(0)
546 Discover pure and const functions
549 Common Report Var(flag_ipa_pta) Init(0)
550 Perform interprocedural points-to analysis
553 Common Report Var(flag_ipa_reference) Init(0)
554 Discover readonly and non addressable static variables
557 Common Report Var(flag_ipa_type_escape) Init(0)
558 Type based escape and alias analysis
561 Common Report Var(flag_ivopts) Init(1)
562 Optimize induction variables on trees
565 Common Var(flag_jump_tables) Init(1)
566 Use jump tables for sufficiently large switch statements
568 fkeep-inline-functions
569 Common Report Var(flag_keep_inline_functions)
570 Generate code for functions even if they are fully inlined
573 Common Report Var(flag_keep_static_consts) Init(1)
574 Emit static const variables even if they are not used
577 Common Report Var(flag_leading_underscore) Init(-1)
578 Give external symbols a leading underscore
582 Does nothing. Preserved for backward compatibility.
585 Common Report Var(flag_errno_math) Init(0)
586 Set errno after built-in math functions
589 Common Report Var(mem_report)
590 Report on permanent memory allocation
592 ; This will attempt to merge constant section constants, if 1 only
593 ; string constants and constants from constant pool, if 2 also constant
596 Common Report Var(flag_merge_constants,2) Init(1)
597 Attempt to merge identical constants and constant variables
600 Common Report Var(flag_merge_constants,1) VarExists
601 Attempt to merge identical constants across compilation units
604 Common RejectNegative Joined UInteger
605 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
608 Common Report Var(flag_modulo_sched)
609 Perform SMS based modulo scheduling before the first scheduling pass
611 fmove-loop-invariants
612 Common Report Var(flag_move_loop_invariants) Init(1)
613 Move loop invariant computations out of loops
616 Common RejectNegative Report Var(flag_mudflap)
617 Add mudflap bounds-checking instrumentation for single-threaded program
620 Common RejectNegative Report VarExists Var(flag_mudflap,2)
621 Add mudflap bounds-checking instrumentation for multi-threaded program
624 Common RejectNegative Report Var(flag_mudflap_ignore_reads)
625 Ignore read operations when inserting mudflap instrumentation
627 freschedule-modulo-scheduled-loops
628 Common Report Var(flag_resched_modulo_sched)
629 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
632 Common Report Var(flag_non_call_exceptions)
633 Support synchronous non-call exceptions
636 Common Report Var(flag_omit_frame_pointer)
637 When possible do not generate stack frames
639 foptimize-register-move
640 Common Report Var(flag_regmove)
641 Do the full register move optimization pass
643 foptimize-sibling-calls
644 Common Report Var(flag_optimize_sibling_calls)
645 Optimize sibling and tail recursive calls
648 Common Report Var(flag_pack_struct)
649 Pack structure members together without holes
652 Common RejectNegative Joined UInteger
653 -fpack-struct=<number> Set initial maximum structure member alignment
656 Common Report Var(flag_pcc_struct_return,1) VarExists
657 Return small aggregates in memory, not registers
660 Common Report Var(flag_peel_loops)
664 Common Report Var(flag_no_peephole,0)
665 Enable machine specific peephole optimizations
668 Common Report Var(flag_peephole2)
669 Enable an RTL peephole pass before sched2
672 Common Report Var(flag_pic,2)
673 Generate position-independent code if possible (large mode)
676 Common Report Var(flag_pie,2)
677 Generate position-independent code for executables if possible (large mode)
680 Common Report Var(flag_pic,1) VarExists
681 Generate position-independent code if possible (small mode)
684 Common Report Var(flag_pie,1) VarExists
685 Generate position-independent code for executables if possible (small mode)
687 fprefetch-loop-arrays
688 Common Report Var(flag_prefetch_loop_arrays)
689 Generate prefetch instructions, if available, for arrays in loops
692 Common Report Var(profile_flag)
693 Enable basic program profiling code
696 Common Report Var(profile_arc_flag)
697 Insert arc-based program profiling code
701 Enable common options for generating profile info for profile feedback directed optimizations
705 Enable common options for performing profile feedback directed optimizations
708 Common Report Var(flag_profile_values)
709 Insert code to profile values of expressions
715 Common Joined RejectNegative
716 -frandom-seed=<string> Make compile reproducible using <string>
719 Common Report Var(flag_pcc_struct_return,0) VarExists
720 Return small aggregates in registers
723 Common Report Var(flag_regmove)
724 Enables a register move optimization
727 Common Report Var(flag_rename_registers) Init(2)
728 Perform a register renaming optimization pass
731 Common Report Var(flag_reorder_blocks)
732 Reorder basic blocks to improve code placement
734 freorder-blocks-and-partition
735 Common Report Var(flag_reorder_blocks_and_partition)
736 Reorder basic blocks and partition into hot and cold sections
739 Common Report Var(flag_reorder_functions)
740 Reorder functions to improve code placement
742 frerun-cse-after-loop
743 Common Report Var(flag_rerun_cse_after_loop) Init(2)
744 Add a common subexpression elimination pass after loop optimizations
748 Does nothing. Preserved for backward compatibility.
751 Common Report Var(flag_rounding_math)
752 Disable optimizations that assume default FP rounding behavior
755 Common Report Var(flag_schedule_interblock) Init(1)
756 Enable scheduling across basic blocks
759 Common Report Var(flag_schedule_speculative) Init(1)
760 Allow speculative motion of non-loads
763 Common Report Var(flag_schedule_speculative_load)
764 Allow speculative motion of some loads
766 fsched-spec-load-dangerous
767 Common Report Var(flag_schedule_speculative_load_dangerous)
768 Allow speculative motion of more loads
771 Common RejectNegative Joined
772 -fsched-verbose=<number> Set the verbosity level of the scheduler
774 fsched2-use-superblocks
775 Common Report Var(flag_sched2_use_superblocks)
776 If scheduling post reload, do superblock scheduling
779 Common Report Var(flag_sched2_use_traces)
780 If scheduling post reload, do trace scheduling
783 Common Report Var(flag_schedule_insns)
784 Reschedule instructions before register allocation
787 Common Report Var(flag_schedule_insns_after_reload)
788 Reschedule instructions after register allocation
790 ; sched_stalled_insns means that insns can be moved prematurely from the queue
791 ; of stalled insns into the ready list.
793 Common Report Var(flag_sched_stalled_insns)
794 Allow premature scheduling of queued insns
796 fsched-stalled-insns=
797 Common RejectNegative Joined UInteger
798 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
800 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
801 ; be examined for a dependency on a stalled insn that is candidate for
802 ; premature removal from the queue of stalled insns into the ready list (has
803 ; an effect only if the flag 'sched_stalled_insns' is set).
804 fsched-stalled-insns-dep
805 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1)
806 Set dependence distance checking in premature scheduling of queued insns
808 fsched-stalled-insns-dep=
809 Common RejectNegative Joined UInteger
810 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
813 Common Report Var(flag_section_anchors)
814 Access data in the same section from shared anchor points
816 frtl-abstract-sequences
817 Common Report Var(flag_rtl_seqabstr)
818 Perform sequence abstraction optimization on RTL
821 Common Report Var(flag_see) Init(0)
822 Eliminate redundant sign extensions using LCM.
825 Common C ObjC C++ ObjC++ Report Var(flag_show_column) Init(1)
826 Show column numbers in diagnostics, when available. Default on
829 Common Report Var(flag_signaling_nans)
830 Disable optimizations observable by IEEE signaling NaNs
832 fsingle-precision-constant
833 Common Report Var(flag_single_precision_constant)
834 Convert floating point constants to single precision constants
836 fsplit-ivs-in-unroller
837 Common Report Var(flag_split_ivs_in_unroller) Init(1)
838 Split lifetimes of induction variables when loops are unrolled
840 fvariable-expansion-in-unroller
841 Common Report Var(flag_variable_expansion_in_unroller)
842 Apply variable expansion when loops are unrolled
844 ; Emit code to probe the stack, to help detect stack overflow; also
845 ; may cause large objects to be allocated dynamically.
847 Common Report Var(flag_stack_check)
848 Insert stack checking code into the program
853 fstack-limit-register=
854 Common RejectNegative Joined
855 -fstack-limit-register=<register> Trap if the stack goes past <register>
858 Common RejectNegative Joined
859 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
862 Common Report Var(flag_stack_protect, 1)
863 Use propolice as a stack protection method
866 Common Report RejectNegative Var(flag_stack_protect, 2) VarExists
867 Use a stack protection method for every function
871 Does nothing. Preserved for backward compatibility.
873 ; Nonzero if we should do (language-dependent) alias analysis.
874 ; Typically, this analysis will assume that expressions of certain
875 ; types do not alias expressions of certain other types. Only used
876 ; if alias analysis (in general) is enabled.
878 Common Report Var(flag_strict_aliasing)
879 Assume strict aliasing rules apply
882 Common Report Var(flag_strict_overflow)
883 Treat signed overflow as undefined
886 Common Report Var(flag_syntax_only)
887 Check for syntax errors, then stop
890 Common Report Var(flag_test_coverage)
891 Create data files needed by \"gcov\"
894 Common Report Var(flag_thread_jumps)
895 Perform jump threading optimizations
898 Common Report Var(time_report)
899 Report the time taken by each compiler pass
902 Common Joined RejectNegative
903 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
906 Common Report Var(flag_toplevel_reorder) Init(1)
907 Reorder top level functions, variables, and asms
910 Common Report Var(flag_tracer)
911 Perform superblock formation via tail duplication
913 ; Zero means that floating-point math operations cannot generate a
914 ; (user-visible) trap. This is the case, for example, in nonstop
915 ; IEEE 754 arithmetic.
917 Common Report Var(flag_trapping_math) Init(1)
918 Assume floating-point operations can trap
921 Common Report Var(flag_trapv)
922 Trap for signed overflow in addition, subtraction and multiplication
925 Common Report Var(flag_tree_ccp)
926 Enable SSA-CCP optimization on trees
929 Common Report Var(flag_tree_store_ccp)
930 Enable SSA-CCP optimization for stores and loads
933 Common Report Var(flag_tree_ch)
934 Enable loop header copying on trees
937 Common Report Var(flag_tree_combine_temps)
938 Coalesce memory temporaries in the SSA->normal pass
941 Common Report Var(flag_tree_copyrename)
942 Replace SSA temporaries with better names in copies
945 Common Report Var(flag_tree_copy_prop)
946 Enable copy propagation on trees
948 ftree-store-copy-prop
949 Common Report Var(flag_tree_store_copy_prop)
950 Enable copy propagation for stores and loads
953 Common Report Var(flag_tree_dce)
954 Enable SSA dead code elimination optimization on trees
957 Common Report Var(flag_tree_dom)
958 Enable dominator optimizations
961 Common Report Var(flag_tree_dse)
962 Enable dead store elimination
965 Common Report Var(flag_tree_fre)
966 Enable Full Redundancy Elimination (FRE) on trees
969 Common Report Var(flag_tree_loop_im) Init(1)
970 Enable loop invariant motion on trees
973 Common Report Var(flag_tree_loop_linear)
974 Enable linear loop transforms on trees
977 Common Report Var(flag_tree_loop_ivcanon) Init(1)
978 Create canonical induction variables in loops
981 Common Report Var(flag_tree_loop_optimize) Init(1)
982 Enable loop optimizations on tree level
985 Common Report Var(flag_tree_pre)
986 Enable SSA-PRE optimization on trees
989 Common Report Var(flag_tree_salias)
990 Perform structural alias analysis
993 Common Report Var(flag_tree_sink)
994 Enable SSA code sinking on trees
997 Common Report Var(flag_tree_sra)
998 Perform scalar replacement of aggregates
1001 Common Report Var(flag_tree_ter)
1002 Replace temporary expressions in the SSA->normal pass
1005 Common Report Var(flag_tree_live_range_split)
1006 Perform live range splitting during the SSA->normal pass
1009 Common Report Var(flag_tree_vrp) Init(0)
1010 Perform Value Range Propagation on trees
1013 Common Report Var(flag_unit_at_a_time)
1014 Compile whole compilation unit at a time
1017 Common Report Var(flag_unroll_loops)
1018 Perform loop unrolling when iteration count is known
1021 Common Report Var(flag_unroll_all_loops)
1022 Perform loop unrolling for all loops
1024 ; Nonzero means that loop optimizer may assume that the induction variables
1025 ; that control loops do not overflow and that the loops with nontrivial
1026 ; exit condition are not infinite
1027 funsafe-loop-optimizations
1028 Common Report Var(flag_unsafe_loop_optimizations)
1029 Allow loop optimizations to assume that the loops behave in normal way
1031 ; Nonzero means that unsafe floating-point math optimizations are allowed
1032 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
1033 ; are allowed to assume that their arguments and results are "normal"
1034 ; (e.g., nonnegative for SQRT).
1035 funsafe-math-optimizations
1036 Common Report Var(flag_unsafe_math_optimizations)
1037 Allow math optimizations that may violate IEEE or ISO standards
1040 Common Report Var(flag_unswitch_loops)
1041 Perform loop unswitching
1044 Common Report Var(flag_unwind_tables)
1045 Just generate unwind tables for exception handling
1048 Common Report Var(flag_var_tracking) VarExists
1049 Perform variable tracking
1052 Common Report Var(flag_tree_vectorize)
1053 Enable loop vectorization on trees
1055 ftree-vect-loop-version
1056 Common Report Var(flag_tree_vect_loop_version) Init(1)
1057 Enable loop versioning when doing loop vectorization on trees
1059 ftree-vectorizer-verbose=
1060 Common RejectNegative Joined
1061 -ftree-vectorizer-verbose=<number> Set the verbosity level of the vectorizer
1063 ; -fverbose-asm causes extra commentary information to be produced in
1064 ; the generated assembly code (to make it more readable). This option
1065 ; is generally only of use to those who actually need to read the
1066 ; generated assembly code (perhaps while debugging the compiler itself).
1067 ; -fno-verbose-asm, the default, causes the extra information
1068 ; to not be added and is useful when comparing two assembler files.
1070 Common Report Var(flag_verbose_asm)
1071 Add extra commentary to assembler output
1074 Common Joined RejectNegative
1075 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
1079 Common Report Var(flag_value_profile_transformations)
1080 Use expression value profiles in optimizations
1083 Common Report Var(flag_web) Init(2)
1084 Construct webs and split unrelated uses of single variable
1087 Common Report Var(flag_whole_program) Init(0)
1088 Perform whole program optimizations
1091 Common Report Var(flag_wrapv)
1092 Assume signed arithmetic overflow wraps around
1094 fzero-initialized-in-bss
1095 Common Report Var(flag_zero_initialized_in_bss) Init(1)
1096 Put zero initialized data in the bss section
1099 Common JoinedOrMissing
1100 Generate debug information in default format
1103 Common JoinedOrMissing Negative(gdwarf-2)
1104 Generate debug information in COFF format
1107 Common JoinedOrMissing Negative(gstabs)
1108 Generate debug information in DWARF v2 format
1111 Common JoinedOrMissing
1112 Generate debug information in default extended format
1115 Common JoinedOrMissing Negative(gstabs+)
1116 Generate debug information in STABS format
1119 Common JoinedOrMissing Negative(gvms)
1120 Generate debug information in extended STABS format
1123 Common JoinedOrMissing Negative(gxcoff)
1124 Generate debug information in VMS format
1127 Common JoinedOrMissing Negative(gxcoff+)
1128 Generate debug information in XCOFF format
1131 Common JoinedOrMissing Negative(gcoff)
1132 Generate debug information in extended XCOFF format
1135 Common Joined Separate
1136 -o <file> Place output into <file>
1139 Common Var(profile_flag)
1140 Enable function profiling
1143 Common Var(pedantic)
1144 Issue warnings needed for strict compliance to the standard
1148 Like -pedantic but issue them as errors
1151 Common Var(quiet_flag)
1152 Do not display functions compiled or elapsed time
1155 Common Var(version_flag)
1156 Display the compiler's version
1159 Common Var(inhibit_warnings)
1162 ; This comment is to ensure we retain the blank line above.