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_always_true)
62 Warn about comparisons that always evaluate to true
65 Common Var(warn_attributes) Init(1)
66 Warn about inappropriate attribute usage
69 Common Var(warn_cast_align)
70 Warn about pointer casts which increase alignment
72 Wdeprecated-declarations
73 Common Var(warn_deprecated_decl) Init(1)
74 Warn about uses of __attribute__((deprecated)) declarations
76 Wdisabled-optimization
77 Common Var(warn_disabled_optimization)
78 Warn when an optimization pass is disabled
81 Common Var(warnings_are_errors)
82 Treat all warnings as errors
86 Treat specified warning as error
90 Print extra (possibly unwanted) warnings
93 Common Var(flag_fatal_errors)
94 Exit on the first error occurred
97 Common Var(warn_inline)
98 Warn when an inlined function cannot be inlined
101 Common RejectNegative Joined UInteger
102 -Wlarger-than-<number> Warn if an object 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
140 Wstring-literal-comparison
141 Common Var(warn_string_literal_comparison)
142 Warn about comparisons to constant string literals
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
192 Wvolatile-register-var
193 Common Var(warn_register_var)
194 Warn when a register variable is declared volatile
198 -aux-info <file> Emit declaration information into <file>
211 -d<letters> Enable dumps from specific passes of the compiler
215 -dumpbase <file> Set the file basename to be used for dumps
217 ; The version of the C++ ABI in use. The following values are allowed:
219 ; 0: The version of the ABI believed most conformant with the C++ ABI
220 ; specification. This ABI may change as bugs are discovered and fixed.
221 ; Therefore, 0 will not necessarily indicate the same ABI in different
224 ; 1: The version of the ABI first used in G++ 3.2.
226 ; Additional positive integers will be assigned as new versions of
227 ; the ABI become the default version of the ABI.
229 Common Joined UInteger Var(flag_abi_version) Init(2)
232 Common Report Var(align_functions,0)
233 Align the start of functions
236 Common RejectNegative Joined UInteger
239 Common Report Var(align_jumps,0)
240 Align labels which are only reached by jumping
243 Common RejectNegative Joined UInteger
246 Common Report Var(align_labels,0)
250 Common RejectNegative Joined UInteger
253 Common Report Var(align_loops)
254 Align the start of loops
257 Common RejectNegative Joined UInteger
259 ; This flag is only tested if alias checking is enabled.
260 ; 0 if pointer arguments may alias each other. True in C.
261 ; 1 if pointer arguments may not alias each other but may alias
263 ; 2 if pointer arguments may not alias each other and may not
264 ; alias global variables.
265 ; 3 if pointer arguments may not alias anything. True in Fortran.
266 ; Set by the front end.
268 Common Report Var(flag_argument_noalias,0)
269 Specify that arguments may alias each other and globals
272 Common Report Var(flag_argument_noalias,1) VarExists
273 Assume arguments may alias globals but not each other
275 fargument-noalias-global
276 Common Report Var(flag_argument_noalias,2) VarExists
277 Assume arguments alias neither each other nor globals
279 fargument-noalias-anything
280 Common Report Var(flag_argument_noalias,3) VarExists
281 Assume arguments alias no other storage
283 fasynchronous-unwind-tables
284 Common Report Var(flag_asynchronous_unwind_tables)
285 Generate unwind tables that are exact at each instruction boundary
287 ; -fcheck-bounds causes gcc to generate array bounds checks.
288 ; For C, C++ and ObjC: defaults off.
289 ; For Java: defaults to on.
290 ; For Fortran: defaults to off.
292 Common Report Var(flag_bounds_check)
293 Generate code to check bounds before indexing arrays
296 Common Report Var(flag_branch_on_count_reg) Init(1)
297 Replace add, compare, branch with branch on count register
299 fbranch-probabilities
300 Common Report Var(flag_branch_probabilities)
301 Use profiling information for branch probabilities
303 fbranch-target-load-optimize
304 Common Report Var(flag_branch_target_load_optimize)
305 Perform branch target load optimization before prologue / epilogue threading
307 fbranch-target-load-optimize2
308 Common Report Var(flag_branch_target_load_optimize2)
309 Perform branch target load optimization after prologue / epilogue threading
312 Common Report Var(flag_btr_bb_exclusive)
313 Restrict target load migration not to re-use registers in any basic block
316 Common Joined RejectNegative
317 -fcall-saved-<register> Mark <register> as being preserved across functions
320 Common Joined RejectNegative
321 -fcall-used-<register> Mark <register> as being corrupted by function calls
323 ; Nonzero for -fcaller-saves: allocate values in regs that need to
324 ; be saved across function calls, if that produces overall better code.
325 ; Optional now, so people can test it.
327 Common Report Var(flag_caller_saves)
328 Save registers around function calls
331 Common Report Var(flag_no_common,0)
332 Do not put uninitialized globals in the common section
335 Common Report Var(flag_cprop_registers)
336 Perform a register copy-propagation optimization pass
339 Common Report Var(flag_crossjumping)
340 Perform cross-jumping optimization
343 Common Report Var(flag_cse_follow_jumps)
344 When running CSE, follow jumps to their targets
347 Common Report Var(flag_cse_skip_blocks)
348 When running CSE, follow conditional jumps
351 Common Report Var(flag_cx_limited_range)
352 Omit range reduction step when performing complex division
355 Common Report Var(flag_data_sections)
356 Place data items into their own section
358 ; Nonzero for -fdefer-pop: don't pop args after each function call
359 ; instead save them up to pop many calls' args with one insns.
361 Common Report Var(flag_defer_pop)
362 Defer popping functions args from stack until later
365 Common Report Var(flag_delayed_branch)
366 Attempt to fill delay slots of branch instructions
368 fdelete-null-pointer-checks
369 Common Report Var(flag_delete_null_pointer_checks)
370 Delete useless null pointer checks
372 fdiagnostics-show-location=
373 Common Joined RejectNegative
374 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
376 fdiagnostics-show-option
378 Amend appropriate diagnostic messages with the command line option that controls them
381 Common Joined RejectNegative
382 -fdump-<type> Dump various compiler internals to a file
385 Common Report Var(flag_dump_noaddr)
386 Suppress output of addresses in debugging dumps
389 Common Report Var(flag_dump_unnumbered) VarExists
390 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
393 Common Report Var(flag_early_inlining) Init(1)
394 Perform early inlining
396 feliminate-dwarf2-dups
397 Common Report Var(flag_eliminate_dwarf2_dups)
398 Perform DWARF2 duplicate elimination
400 feliminate-unused-debug-symbols
401 Common Report Var(flag_debug_only_used_symbols)
402 Perform unused type elimination in debug info
404 feliminate-unused-debug-types
405 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
406 Perform unused type elimination in debug info
408 femit-class-debug-always
409 Common Report Var(flag_emit_class_debug_always) Init(1)
410 Do not suppress C++ class debug information.
413 Common Report Var(flag_exceptions)
414 Enable exception handling
416 fexpensive-optimizations
417 Common Report Var(flag_expensive_optimizations)
418 Perform a number of minor, expensive optimizations
424 Common Report Var(flag_finite_math_only)
425 Assume no NaNs or infinities are generated
428 Common Joined RejectNegative
429 -ffixed-<register> Mark <register> as being unavailable to the compiler
432 Common Report Var(flag_float_store)
433 Don't allocate floats and doubles in extended-precision registers
435 ; Nonzero for -fforce-addr: load memory address into a register before
436 ; reference to memory. This makes better cse but slower compilation.
438 Common Report Var(flag_force_addr)
439 Copy memory address constants into registers before use
441 ; Nonzero for -fforce-mem: load memory value into a register
442 ; before arithmetic on it. This makes better cse but slower compilation.
444 Common Report Var(flag_force_mem)
445 Copy memory operands into registers before use
448 Common Report Var(flag_forward_propagate)
449 Perform a forward propagation pass on RTL
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(1)
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(pre_ipa_mem_report)
649 Report on memory allocation before interprocedural optimization
652 Common Report Var(post_ipa_mem_report)
653 Report on memory allocation before interprocedural optimization
656 Common Report Var(flag_pack_struct)
657 Pack structure members together without holes
660 Common RejectNegative Joined UInteger
661 -fpack-struct=<number> Set initial maximum structure member alignment
664 Common Report Var(flag_pcc_struct_return,1) VarExists
665 Return small aggregates in memory, not registers
668 Common Report Var(flag_peel_loops)
672 Common Report Var(flag_no_peephole,0)
673 Enable machine specific peephole optimizations
676 Common Report Var(flag_peephole2)
677 Enable an RTL peephole pass before sched2
680 Common Report Var(flag_pic,2)
681 Generate position-independent code if possible (large mode)
684 Common Report Var(flag_pie,2)
685 Generate position-independent code for executables if possible (large mode)
688 Common Report Var(flag_pic,1) VarExists
689 Generate position-independent code if possible (small mode)
692 Common Report Var(flag_pie,1) VarExists
693 Generate position-independent code for executables if possible (small mode)
695 fprefetch-loop-arrays
696 Common Report Var(flag_prefetch_loop_arrays)
697 Generate prefetch instructions, if available, for arrays in loops
700 Common Report Var(profile_flag)
701 Enable basic program profiling code
704 Common Report Var(profile_arc_flag)
705 Insert arc-based program profiling code
709 Enable common options for generating profile info for profile feedback directed optimizations
713 Enable common options for performing profile feedback directed optimizations
716 Common Report Var(flag_profile_values)
717 Insert code to profile values of expressions
723 Common Joined RejectNegative
724 -frandom-seed=<string> Make compile reproducible using <string>
726 ; This switch causes the command line that was used to create an
727 ; object file to be recorded into the object file. The exact format
728 ; of this recording is target and binary file format dependent.
729 ; It is related to the -fverbose-asm switch, but that switch only
730 ; records information in the assembler output file as comments, so
731 ; they never reach the object file.
733 Common Report Var(flag_record_gcc_switches)
734 Record gcc command line switches in the object file.
737 Common Report Var(flag_pcc_struct_return,0) VarExists
738 Return small aggregates in registers
741 Common Report Var(flag_regmove)
742 Enables a register move optimization
745 Common Report Var(flag_rename_registers) Init(2)
746 Perform a register renaming optimization pass
749 Common Report Var(flag_reorder_blocks)
750 Reorder basic blocks to improve code placement
752 freorder-blocks-and-partition
753 Common Report Var(flag_reorder_blocks_and_partition)
754 Reorder basic blocks and partition into hot and cold sections
757 Common Report Var(flag_reorder_functions)
758 Reorder functions to improve code placement
760 frerun-cse-after-loop
761 Common Report Var(flag_rerun_cse_after_loop) Init(2)
762 Add a common subexpression elimination pass after loop optimizations
766 Does nothing. Preserved for backward compatibility.
769 Common Report Var(flag_rounding_math)
770 Disable optimizations that assume default FP rounding behavior
773 Common Report Var(flag_schedule_interblock) Init(1)
774 Enable scheduling across basic blocks
777 Common Report Var(flag_schedule_speculative) Init(1)
778 Allow speculative motion of non-loads
781 Common Report Var(flag_schedule_speculative_load)
782 Allow speculative motion of some loads
784 fsched-spec-load-dangerous
785 Common Report Var(flag_schedule_speculative_load_dangerous)
786 Allow speculative motion of more loads
789 Common RejectNegative Joined
790 -fsched-verbose=<number> Set the verbosity level of the scheduler
792 fsched2-use-superblocks
793 Common Report Var(flag_sched2_use_superblocks)
794 If scheduling post reload, do superblock scheduling
797 Common Report Var(flag_sched2_use_traces)
798 If scheduling post reload, do trace scheduling
801 Common Report Var(flag_schedule_insns)
802 Reschedule instructions before register allocation
805 Common Report Var(flag_schedule_insns_after_reload)
806 Reschedule instructions after register allocation
808 ; sched_stalled_insns means that insns can be moved prematurely from the queue
809 ; of stalled insns into the ready list.
811 Common Report Var(flag_sched_stalled_insns)
812 Allow premature scheduling of queued insns
814 fsched-stalled-insns=
815 Common RejectNegative Joined UInteger
816 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
818 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
819 ; be examined for a dependency on a stalled insn that is candidate for
820 ; premature removal from the queue of stalled insns into the ready list (has
821 ; an effect only if the flag 'sched_stalled_insns' is set).
822 fsched-stalled-insns-dep
823 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1)
824 Set dependence distance checking in premature scheduling of queued insns
826 fsched-stalled-insns-dep=
827 Common RejectNegative Joined UInteger
828 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
831 Common Report Var(flag_section_anchors)
832 Access data in the same section from shared anchor points
834 frtl-abstract-sequences
835 Common Report Var(flag_rtl_seqabstr)
836 Perform sequence abstraction optimization on RTL
839 Common Report Var(flag_see) Init(0)
840 Eliminate redundant sign extensions using LCM.
843 Common C ObjC C++ ObjC++ Report Var(flag_show_column) Init(1)
844 Show column numbers in diagnostics, when available. Default on
847 Common Report Var(flag_signaling_nans)
848 Disable optimizations observable by IEEE signaling NaNs
850 fsingle-precision-constant
851 Common Report Var(flag_single_precision_constant)
852 Convert floating point constants to single precision constants
854 fsplit-ivs-in-unroller
855 Common Report Var(flag_split_ivs_in_unroller) Init(1)
856 Split lifetimes of induction variables when loops are unrolled
858 fvariable-expansion-in-unroller
859 Common Report Var(flag_variable_expansion_in_unroller)
860 Apply variable expansion when loops are unrolled
862 ; Emit code to probe the stack, to help detect stack overflow; also
863 ; may cause large objects to be allocated dynamically.
865 Common Report Var(flag_stack_check)
866 Insert stack checking code into the program
871 fstack-limit-register=
872 Common RejectNegative Joined
873 -fstack-limit-register=<register> Trap if the stack goes past <register>
876 Common RejectNegative Joined
877 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
880 Common Report Var(flag_stack_protect, 1)
881 Use propolice as a stack protection method
884 Common Report RejectNegative Var(flag_stack_protect, 2) VarExists
885 Use a stack protection method for every function
889 Does nothing. Preserved for backward compatibility.
891 ; Nonzero if we should do (language-dependent) alias analysis.
892 ; Typically, this analysis will assume that expressions of certain
893 ; types do not alias expressions of certain other types. Only used
894 ; if alias analysis (in general) is enabled.
896 Common Report Var(flag_strict_aliasing)
897 Assume strict aliasing rules apply
900 Common Report Var(flag_syntax_only)
901 Check for syntax errors, then stop
904 Common Report Var(flag_test_coverage)
905 Create data files needed by \"gcov\"
908 Common Report Var(flag_thread_jumps)
909 Perform jump threading optimizations
912 Common Report Var(time_report)
913 Report the time taken by each compiler pass
916 Common Joined RejectNegative
917 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
920 Common Report Var(flag_toplevel_reorder) Init(1)
921 Reorder top level functions, variables, and asms
924 Common Report Var(flag_tracer)
925 Perform superblock formation via tail duplication
927 ; Zero means that floating-point math operations cannot generate a
928 ; (user-visible) trap. This is the case, for example, in nonstop
929 ; IEEE 754 arithmetic.
931 Common Report Var(flag_trapping_math) Init(1)
932 Assume floating-point operations can trap
935 Common Report Var(flag_trapv)
936 Trap for signed overflow in addition, subtraction and multiplication
939 Common Report Var(flag_tree_ccp)
940 Enable SSA-CCP optimization on trees
943 Common Report Var(flag_tree_store_ccp)
944 Enable SSA-CCP optimization for stores and loads
947 Common Report Var(flag_tree_ch)
948 Enable loop header copying on trees
951 Common Report Var(flag_tree_copyrename)
952 Replace SSA temporaries with better names in copies
955 Common Report Var(flag_tree_copy_prop)
956 Enable copy propagation on trees
958 ftree-store-copy-prop
959 Common Report Var(flag_tree_store_copy_prop)
960 Enable copy propagation for stores and loads
963 Common Report Var(flag_tree_dce)
964 Enable SSA dead code elimination optimization on trees
967 Common Report Var(flag_tree_dom)
968 Enable dominator optimizations
971 Common Report Var(flag_tree_dse)
972 Enable dead store elimination
975 Common Report Var(flag_tree_fre)
976 Enable Full Redundancy Elimination (FRE) on trees
979 Common Report Var(flag_tree_loop_im) Init(1)
980 Enable loop invariant motion on trees
983 Common Report Var(flag_tree_loop_linear)
984 Enable linear loop transforms on trees
987 Common Report Var(flag_tree_loop_ivcanon) Init(1)
988 Create canonical induction variables in loops
991 Common Report Var(flag_tree_loop_optimize) Init(1)
992 Enable loop optimizations on tree level
995 Common Report Var(flag_tree_pre)
996 Enable SSA-PRE optimization on trees
999 Common Report Var(flag_tree_salias)
1000 Perform structural alias analysis
1003 Common Report Var(flag_tree_sink)
1004 Enable SSA code sinking on trees
1007 Common Report Var(flag_tree_sra)
1008 Perform scalar replacement of aggregates
1011 Common Report Var(flag_tree_ter)
1012 Replace temporary expressions in the SSA->normal pass
1015 Common Report Var(flag_tree_vrp) Init(0)
1016 Perform Value Range Propagation on trees
1019 Common Report Var(flag_unit_at_a_time)
1020 Compile whole compilation unit at a time
1023 Common Report Var(flag_unroll_loops)
1024 Perform loop unrolling when iteration count is known
1027 Common Report Var(flag_unroll_all_loops)
1028 Perform loop unrolling for all loops
1030 ; Nonzero means that loop optimizer may assume that the induction variables
1031 ; that control loops do not overflow and that the loops with nontrivial
1032 ; exit condition are not infinite
1033 funsafe-loop-optimizations
1034 Common Report Var(flag_unsafe_loop_optimizations)
1035 Allow loop optimizations to assume that the loops behave in normal way
1037 ; Nonzero means that unsafe floating-point math optimizations are allowed
1038 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
1039 ; are allowed to assume that their arguments and results are "normal"
1040 ; (e.g., nonnegative for SQRT).
1041 funsafe-math-optimizations
1042 Common Report Var(flag_unsafe_math_optimizations)
1043 Allow math optimizations that may violate IEEE or ISO standards
1046 Common Report Var(flag_unswitch_loops)
1047 Perform loop unswitching
1050 Common Report Var(flag_unwind_tables)
1051 Just generate unwind tables for exception handling
1054 Common Report Var(flag_var_tracking) VarExists
1055 Perform variable tracking
1058 Common Report Var(flag_tree_vectorize)
1059 Enable loop vectorization on trees
1061 ftree-vect-loop-version
1062 Common Report Var(flag_tree_vect_loop_version) Init(1)
1063 Enable loop versioning when doing loop vectorization on trees
1065 ftree-vectorizer-verbose=
1066 Common RejectNegative Joined
1067 -ftree-vectorizer-verbose=<number> Set the verbosity level of the vectorizer
1069 ; -fverbose-asm causes extra commentary information to be produced in
1070 ; the generated assembly code (to make it more readable). This option
1071 ; is generally only of use to those who actually need to read the
1072 ; generated assembly code (perhaps while debugging the compiler itself).
1073 ; -fno-verbose-asm, the default, causes the extra information
1074 ; to not be added and is useful when comparing two assembler files.
1076 Common Report Var(flag_verbose_asm)
1077 Add extra commentary to assembler output
1080 Common Joined RejectNegative
1081 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
1085 Common Report Var(flag_value_profile_transformations)
1086 Use expression value profiles in optimizations
1089 Common Report Var(flag_web) Init(2)
1090 Construct webs and split unrelated uses of single variable
1093 Common Report Var(flag_whole_program) Init(0)
1094 Perform whole program optimizations
1097 Common Report Var(flag_wrapv)
1098 Assume signed arithmetic overflow wraps around
1100 fzero-initialized-in-bss
1101 Common Report Var(flag_zero_initialized_in_bss) Init(1)
1102 Put zero initialized data in the bss section
1105 Common JoinedOrMissing
1106 Generate debug information in default format
1109 Common JoinedOrMissing Negative(gdwarf-2)
1110 Generate debug information in COFF format
1113 Common JoinedOrMissing Negative(gstabs)
1114 Generate debug information in DWARF v2 format
1117 Common JoinedOrMissing
1118 Generate debug information in default extended format
1121 Common JoinedOrMissing Negative(gstabs+)
1122 Generate debug information in STABS format
1125 Common JoinedOrMissing Negative(gvms)
1126 Generate debug information in extended STABS format
1129 Common JoinedOrMissing Negative(gxcoff)
1130 Generate debug information in VMS format
1133 Common JoinedOrMissing Negative(gxcoff+)
1134 Generate debug information in XCOFF format
1137 Common JoinedOrMissing Negative(gcoff)
1138 Generate debug information in extended XCOFF format
1141 Common Joined Separate
1142 -o <file> Place output into <file>
1145 Common Var(profile_flag)
1146 Enable function profiling
1149 Common Var(pedantic)
1150 Issue warnings needed for strict compliance to the standard
1154 Like -pedantic but issue them as errors
1157 Common Var(quiet_flag)
1158 Do not display functions compiled or elapsed time
1161 Common Var(version_flag)
1162 Display the compiler's version
1165 Common Var(inhibit_warnings)
1168 ; This comment is to ensure we retain the blank line above.