1 ; Options for the language- and target-independent parts of the compiler.
2 ; Copyright (C) 2003 Free Software Foundation, Inc.
4 ; This file is part of GCC.
6 ; GCC is free software; you can redistribute it and/or modify it under
7 ; the terms of the GNU General Public License as published by the Free
8 ; Software Foundation; either version 2, or (at your option) any later
11 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 ; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 ; You should have received a copy of the GNU General Public License
17 ; along with GCC; see the file COPYING. If not, write to the Free
18 ; Software Foundation, 59 Temple Place - Suite 330, Boston, MA
21 ; See c.opt for a description of this file's format.
23 ; Please try to keep this file in ASCII collating order.
27 Display this information
31 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
40 Common Joined Separate UInteger
41 -G<number> Put global and static data smaller than <number> bytes into a special section (on some targets)
44 Common JoinedOrMissing
45 -O<number> Set optimization level to <number>
49 Optimize for space rather than speed
53 This switch is deprecated; use -Wextra instead
57 Warn about returning structures, unions or arrays
61 Warn about pointer casts which increase alignment
63 Wdeprecated-declarations
65 Warn about uses of __attribute__((deprecated)) declarations
67 Wdisabled-optimization
69 Warn when an optimization pass is disabled
73 Treat all warnings as errors
77 Print extra (possibly unwanted) warnings
81 Warn when an inlined function cannot be inlined
84 Common RejectNegative Joined UInteger
85 -Wlarger-than-<number> Warn if an object is larger than <number> bytes
89 Warn about functions which might be candidates for __attribute__((noreturn))
93 Warn when the packed attribute has no effect on struct layout
97 Warn when padding is required to align structure members
101 Warn when one local variable shadows another
105 Warn about code which might break strict aliasing rules
109 Warn about enumerated switches, with no default, missing a case
113 Warn about enumerated switches missing a \"default:\" statement
117 Warn about all enumerated switches missing a specific case
121 Do not suppress warnings from system headers
125 Warn about uninitialized automatic variables
129 Warn about code that will never be executed
133 Enable all -Wunused- warnings
137 Warn when a function is unused
141 Warn when a label is unused
145 Warn when a function parameter is unused
149 Warn when an expression value is unused
153 Warn when a variable is unused
157 -aux-info <file> Emit declaration information into <file>
170 -d<letters> Enable dumps from specific passes of the compiler
174 -dumpbase <file> Set the file basename to be used for dumps
183 Common Joined UInteger
187 Align the start of functions
190 Common RejectNegative Joined UInteger
194 Align labels which are only reached by jumping
197 Common RejectNegative Joined UInteger
204 Common RejectNegative Joined UInteger
208 Align the start of loops
211 Common RejectNegative Joined UInteger
215 Specify that arguments may alias each other and globals
219 Assume arguments may alias globals but not each other
221 fargument-noalias-global
223 Assume arguments alias neither each other nor globals
225 fasynchronous-unwind-tables
227 Generate unwind tables that are exact at each instruction boundary
231 Generate code to check bounds before indexing arrays
235 Replace add, compare, branch with branch on count register
237 fbranch-probabilities
239 Use profiling information for branch probabilities
241 fbranch-target-load-optimize
243 Perform branch target load optimization before prologue / epilogue threading
245 fbranch-target-load-optimize2
247 Perform branch target load optimization after prologue / epilogue threading
250 Common Joined RejectNegative
251 -fcall-saved-<register> Mark <register> as being preserved across functions
254 Common Joined RejectNegative
255 -fcall-used-<register> Mark <register> as being corrupted by function calls
259 Save registers around function calls
263 Do not put uninitialized globals in the common section
267 Perform a register copy-propagation optimization pass
271 Perform cross-jumping optimization
275 When running CSE, follow jumps to their targets
279 When running CSE, follow conditional jumps
283 Place data items into their own section
287 Defer popping functions args from stack until later
291 Attempt to fill delay slots of branch instructions
293 fdelete-null-pointer-checks
295 Delete useless null pointer checks
297 fdiagnostics-show-location=
298 Common Joined RejectNegative
299 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
303 Suppress output of instruction numbers and line number notes in debugging dumps
305 feliminate-dwarf2-dups
307 Perform DWARF2 duplicate elimination
309 feliminate-unused-debug-symbols
311 Perform unused type elimination in debug info
313 feliminate-unused-debug-types
315 Perform unused type elimination in debug info
319 Enable exception handling
321 fexpensive-optimizations
323 Perform a number of minor, expensive optimizations
330 Assume no NaNs or infinities are generated
333 Common Joined RejectNegative
334 -ffixed-<register> Mark <register> as being unavailable to the compiler
338 Do not store floats in registers
342 Copy memory address constants into registers before use
346 Copy memory operands into registers before use
350 Allow function addresses to be held in registers
354 Place each function into its own section
358 Perform global common subexpression elimination
362 Perform enhanced load motion during global common subexpression elimination
366 Perform store motion after global common subexpression elimination
370 Perform redundant load after store elimination in global common subexpression elimination
372 fguess-branch-probability
374 Enable guessing of branch probabilities
378 Process #ident directives
382 Perform conversion of conditional jumps to branchless equivalents
386 Perform conversion of conditional jumps to conditional execution
388 finhibit-size-directive
390 Do not generate .size directives
394 Pay attention to the \"inline\" keyword
398 Integrate simple functions into their callers
401 Common RejectNegative Joined UInteger
404 Common RejectNegative Joined UInteger
405 -finline-limit=<number> Limit the size of inlined functions to <number>
407 finstrument-functions
409 Instrument function entry and exit with profiling calls
411 fkeep-inline-functions
413 Generate code for functions even if they are fully inlined
417 Emit static const variables even if they are not used
421 Give external symbols a leading underscore
425 Perform loop optimizations
429 Set errno after built-in math functions
433 Report on permanent memory allocation
437 Attempt to merge identical constants and constant variables
441 Attempt to merge identical constants across compilation units
444 Common RejectNegative Joined UInteger
445 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
449 Force all loop invariant computations out of loops
453 Use graph-coloring register allocation
457 Support synchronous non-call exceptions
461 Perform loop unrolling when iteration count is known
463 fold-unroll-all-loops
465 Perform loop unrolling for all loops
469 When possible do not generate stack frames
471 foptimize-register-move
473 Do the full register move optimization pass
475 foptimize-sibling-calls
477 Optimize sibling and tail recursive calls
481 Pack structure members together without holes
485 Return small aggregates in memory, not registers
493 Enable machine specific peephole optimizations
497 Enable an RTL peephole pass before sched2
501 Generate position-independent code if possible
505 Generate position-independent code for executables if possible
507 fprefetch-loop-arrays
509 Generate prefetch instructions, if available, for arrays in loops
513 Enable basic program profiling code
517 Insert arc-based program profiling code
521 Enable common options for generating profile info for profile feedback directed optimizations
525 Enable common options for performing profile feedback directed optimizations
529 Insert code to profile values of expressions
535 Common Joined RejectNegative
536 -frandom-seed=<string> Make compile reproducible using <string>
540 Strength reduce all loop general induction variables
544 Return small aggregates in registers
548 Enables a register move optimization
552 Perform a register renaming optimization pass
556 Reorder basic blocks to improve code placement
560 Reorder functions to improve code placement
562 frerun-cse-after-loop
564 Add a common subexpression elimination pass after loop optimizations
568 Run the loop optimizer twice
572 Disable optimizations that assume default FP rounding behavior
576 Enable scheduling across basic blocks
580 Allow speculative motion of non-loads
584 Allow speculative motion of some loads
586 fsched-spec-load-dangerous
588 Allow speculative motion of more loads
591 Common RejectNegative Joined
592 -fsched-verbose=<number> Set the verbosity level of the scheduler
594 fsched2-use-superblocks
596 If scheduling post reload, do superblock scheduling
600 If scheduling post reload, do trace scheduling
604 Reschedule instructions before register allocation
608 Reschedule instructions after register allocation
612 Allow premature scheduling of queued insns
614 fsched-stalled-insns=
615 Common RejectNegative Joined UInteger
616 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
618 fsched-stalled-insns-dep
620 Set dependence distance checking in premature scheduling of queued insns
622 fsched-stalled-insns-dep=
623 Common RejectNegative Joined UInteger
624 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
628 Mark data as shared rather than private
632 Disable optimizations observable by IEEE signaling NaNs
634 fsingle-precision-constant
636 Convert floating point constants to single precision constants
640 Insert stack checking code into the program
645 fstack-limit-register=
646 Common RejectNegative Joined
647 -fstack-limit-register=<register> Trap if the stack goes past <register>
650 Common RejectNegative Joined
651 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
655 Perform strength reduction optimizations
659 Assume strict aliasing rules apply
663 Check for syntax errors, then stop
667 Create data files needed by \"gcov\"
671 Perform jump threading optimizations
675 Report the time taken by each compiler pass
678 Common Joined RejectNegative
679 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
683 Perform superblock formation via tail duplication
687 Assume floating-point operations can trap
691 Trap for signed overflow in addition, subtraction and multiplication
695 Compile whole compilation unit at a time
699 Perform loop unrolling when iteration count is known
703 Perform loop unrolling for all loops
705 funsafe-math-optimizations
707 Allow math optimizations that may violate IEEE or ISO standards
711 Perform loop unswitching
715 Just generate unwind tables for exception handling
719 Add extra commentary to assembler output
723 Use expression value profiles in optimizations
727 Construct webs and split unrelated uses of single variable
731 Assume signed arithmetic overflow wraps around
735 Store strings in writable data section
737 fzero-initialized-in-bss
739 Put zero initialized data in the bss section
742 Common JoinedOrMissing
743 Generate debug information in default format
746 Common JoinedOrMissing
747 Generate debug information in COFF format
750 Common JoinedOrMissing
751 Generate debug information in DWARF v2 format
754 Common JoinedOrMissing
755 Generate debug information in default extended format
758 Common JoinedOrMissing
759 Generate debug information in STABS format
762 Common JoinedOrMissing
763 Generate debug information in extended STABS format
766 Common JoinedOrMissing
767 Generate debug information in VMS format
770 Common JoinedOrMissing
771 Generate debug information in XCOFF format
774 Common JoinedOrMissing
775 Generate debug information in extended XCOFF format
781 Common Joined Separate
782 -o <file> Place output into <file>
786 Enable function profiling
790 Issue warnings needed for strict compliance to the standard
794 Like -pedantic but issue them as errors
798 Do not display functions compiled or elapsed time
802 Display the compiler's version
808 ; This comment is to ensure we retain the blank line above.