diff options
Diffstat (limited to 'gcc/doc/invoke.texi')
| -rw-r--r-- | gcc/doc/invoke.texi | 253 |
1 files changed, 195 insertions, 58 deletions
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index d62d2ddc99e..7bf45914c73 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -238,13 +238,14 @@ Objective-C and Objective-C++ Dialects}. -Wparentheses -Wpointer-arith -Wno-pointer-to-int-cast @gol -Wredundant-decls @gol -Wreturn-type -Wsequence-point -Wshadow @gol --Wsign-compare -Wstrict-aliasing -Wstrict-aliasing=2 @gol +-Wsign-compare -Wstack-protector @gol +-Wstrict-aliasing -Wstrict-aliasing=2 @gol -Wswitch -Wswitch-default -Wswitch-enum @gol -Wsystem-headers -Wtrigraphs -Wundef -Wuninitialized @gol -Wunknown-pragmas -Wno-pragmas -Wunreachable-code @gol -Wunused -Wunused-function -Wunused-label -Wunused-parameter @gol --Wunused-value -Wunused-variable -Wwrite-strings @gol --Wvariadic-macros} +-Wunused-value -Wunused-variable -Wvariadic-macros @gol +-Wwrite-strings} @item C-only Warning Options @gccoptlist{-Wbad-function-cast -Wmissing-declarations @gol @@ -281,7 +282,7 @@ Objective-C and Objective-C++ Dialects}. -ftree-vectorizer-verbose=@var{n} @gol -fdump-tree-storeccp@r{[}-@var{n}@r{]} @gol -feliminate-dwarf2-dups -feliminate-unused-debug-types @gol --feliminate-unused-debug-symbols -fmem-report -fprofile-arcs -ftree-based-profiling @gol +-feliminate-unused-debug-symbols -fmem-report -fprofile-arcs @gol -frandom-seed=@var{string} -fsched-verbose=@var{n} @gol -ftest-coverage -ftime-report -fvar-tracking @gol -g -g@var{level} -gcoff -gdwarf-2 @gol @@ -305,7 +306,8 @@ Objective-C and Objective-C++ Dialects}. -fforce-addr -ffunction-sections @gol -fgcse -fgcse-lm -fgcse-sm -fgcse-las -fgcse-after-reload @gol -floop-optimize -fcrossjumping -fif-conversion -fif-conversion2 @gol --finline-functions -finline-limit=@var{n} -fkeep-inline-functions @gol +-finline-functions -finline-functions-called-once @gol +-finline-limit=@var{n} -fkeep-inline-functions @gol -fkeep-static-consts -fmerge-constants -fmerge-all-constants @gol -fmodulo-sched -fno-branch-count-reg @gol -fno-default-inline -fno-defer-pop -fmove-loop-invariants @gol @@ -322,10 +324,11 @@ Objective-C and Objective-C++ Dialects}. -frounding-math -fschedule-insns -fschedule-insns2 @gol -fno-sched-interblock -fno-sched-spec -fsched-spec-load @gol -fsched-spec-load-dangerous @gol --fsched-stalled-insns=@var{n} -sched-stalled-insns-dep=@var{n} @gol +-fsched-stalled-insns=@var{n} -fsched-stalled-insns-dep=@var{n} @gol -fsched2-use-superblocks @gol -fsched2-use-traces -freschedule-modulo-scheduled-loops @gol --fsignaling-nans -fsingle-precision-constant -fspeculative-prefetching @gol +-fsignaling-nans -fsingle-precision-constant @gol +-fstack-protector -fstack-protector-all @gol -fstrength-reduce -fstrict-aliasing -ftracer -fthread-jumps @gol -funroll-all-loops -funroll-loops -fpeel-loops @gol -fsplit-ivs-in-unroller -funswitch-loops @gol @@ -362,7 +365,7 @@ Objective-C and Objective-C++ Dialects}. @item Linker Options @xref{Link Options,,Options for Linking}. @gccoptlist{@var{object-file-name} -l@var{library} @gol --nostartfiles -nodefaultlibs -nostdlib -pie @gol +-nostartfiles -nodefaultlibs -nostdlib -pie -rdynamic @gol -s -static -static-libgcc -shared -shared-libgcc -symbolic @gol -Wl,@var{option} -Xlinker @var{option} @gol -u @var{symbol}} @@ -431,6 +434,9 @@ Objective-C and Objective-C++ Dialects}. -melf -maout -melinux -mlinux -sim -sim2 @gol -mmul-bug-workaround -mno-mul-bug-workaround} +@emph{CRX Options} +@gccoptlist{-mmac -mpush-args} + @emph{Darwin Options} @gccoptlist{-all_load -allowable_client -arch -arch_errors_fatal @gol -arch_only -bind_at_load -bundle -bundle_loader @gol @@ -482,6 +488,7 @@ Objective-C and Objective-C++ Dialects}. -mlinked-fp -mlong-calls -malign-labels @gol -mlibrary-pic -macc-4 -macc-8 @gol -mpack -mno-pack -mno-eflags -mcond-move -mno-cond-move @gol +-moptimize-membar -mno-optimize-membar @gol -mscc -mno-scc -mcond-exec -mno-cond-exec @gol -mvliw-branch -mno-vliw-branch @gol -mmulti-cond-exec -mno-multi-cond-exec -mnested-cond-exec @gol @@ -520,7 +527,7 @@ Objective-C and Objective-C++ Dialects}. -m96bit-long-double -mregparm=@var{num} -msseregparm @gol -momit-leaf-frame-pointer -mno-red-zone -mno-tls-direct-seg-refs @gol -mcmodel=@var{code-model} @gol --m32 -m64} +-m32 -m64 -mlarge-data-threshold=@var{num}} @emph{IA-64 Options} @gccoptlist{-mbig-endian -mlittle-endian -mgnu-as -mgnu-ld -mno-pic @gol @@ -604,6 +611,10 @@ Objective-C and Objective-C++ Dialects}. -mam33-2 -mno-am33-2 @gol -mno-crt0 -mrelax} +@emph{MS1 Options} +@gccoptlist{-mno-crt0 -mmul -mbacc -msim @gol +-march=@var{cpu-type} } + @emph{PDP-11 Options} @gccoptlist{-mfpu -msoft-float -mac0 -mno-ac0 -m40 -m45 -m10 @gol -mbcopy -mbcopy-builtin -mint32 -mno-int16 @gol @@ -856,6 +867,11 @@ preprocessor (not included with GCC)@. @itemx @var{file}.f95 Fortran 90/95 source code which should not be preprocessed. +@item @var{file}.F90 +@itemx @var{file}.F95 +Fortran 90/95 source code which must be preprocessed (with the +traditional preprocessor). + @c FIXME: Descriptions of Java file types. @c @var{file}.java @c @var{file}.class @@ -1791,9 +1807,9 @@ but disables the helpful warning. @item -Wold-style-cast @r{(C++ only)} @opindex Wold-style-cast Warn if an old-style (C-style) cast to a non-void type is used within -a C++ program. The new-style casts (@samp{static_cast}, -@samp{reinterpret_cast}, and @samp{const_cast}) are less vulnerable to -unintended effects and much easier to search for. +a C++ program. The new-style casts (@samp{dynamic_cast}, +@samp{static_cast}, @samp{reinterpret_cast}, and @samp{const_cast}) are +less vulnerable to unintended effects and much easier to search for. @item -Woverloaded-virtual @r{(C++ only)} @opindex Woverloaded-virtual @@ -2726,9 +2742,10 @@ included in @option{-Wall}. @item -Wstrict-aliasing=2 @opindex Wstrict-aliasing=2 This option is only active when @option{-fstrict-aliasing} is active. -It warns about all code which might break the strict aliasing rules that the -compiler is using for optimization. This warning catches all cases, but -it will also give a warning for some ambiguous cases that are safe. +It warns about code which might break the strict aliasing rules that the +compiler is using for optimization. This warning catches more cases than +@option{-Wstrict-aliasing}, but it will also give a warning for some ambiguous +cases that are safe. @item -Wall @opindex Wall @@ -3352,6 +3369,11 @@ This option is only supported for C and Objective-C@. @item -Werror @opindex Werror Make all warnings into errors. + +@item -Wstack-protector +This option is only active when @option{-fstack-protector} is active. It +warns about functions that will not be protected against stack smashing. + @end table @node Debugging Options @@ -3579,17 +3601,6 @@ executed. When an arc is the only exit or only entrance to a block, the instrumentation code can be added to the block; otherwise, a new basic block must be created to hold the instrumentation code. -@item -ftree-based-profiling -@opindex ftree-based-profiling -This option is used in addition to @option{-fprofile-arcs} or -@option{-fbranch-probabilities} to control whether those optimizations -are performed on a tree-based or rtl-based internal representation. -If you use this option when compiling with @option{-fprofile-arcs}, -you must also use it when compiling later with @option{-fbranch-probabilities}. -Currently the tree-based optimization is in an early stage of -development, and this option is recommended only for those people -working on improving it. - @need 2000 @item -ftest-coverage @opindex ftest-coverage @@ -4470,6 +4481,15 @@ assembler code in its own right. Enabled at level @option{-O3}. +@item -finline-functions-called-once +@opindex finline-functions-called-once +Consider all @code{static} functions called once for inlining into their +caller even if they are not marked @code{inline}. If a call to a given +function is integrated, then the function is not output as assembler code +in its own right. + +Enabled if @option{-funit-at-a-time} is enabled. + @item -fearly-inlining @opindex fearly-inlining Inline functions marked by @code{always_inline} and functions whose body seems @@ -4948,8 +4968,11 @@ Perform dead code elimination (DCE) on trees. This flag is enabled by default at @option{-O} and higher. @item -ftree-dominator-opts -Perform dead code elimination (DCE) on trees. This flag is enabled by -default at @option{-O} and higher. +Perform a variety of simple scalar cleanups (constant/copy +propagation, redundancy elimination, range propagation and expression +simplification) based on a dominator tree traversal. This also +performs jump threading (to reduce jumps to jumps). This flag is +enabled by default at @option{-O} and higher. @item -ftree-ch Perform loop header copying on trees. This is beneficial since it increases @@ -5322,8 +5345,9 @@ The following options are enabled: @code{-fprofile-arcs}, @code{-fprofile-values Enable profile feedback directed optimizations, and optimizations generally profitable only with profile feedback available. -The following options are enabled: @code{-fbranch-probabilities}, -@code{-fvpt}, @code{-funroll-loops}, @code{-fpeel-loops}, @code{-ftracer}. +The following options are enabled: @code{-fbranch-probabilities}, @code{-fvpt}, +@code{-funroll-loops}, @code{-fpeel-loops}, @code{-ftracer}, +@code{-fno-loop-optimize}. @end table @@ -5520,23 +5544,6 @@ and actually performs the optimizations based on them. Currently the optimizations include specialization of division operation using the knowledge about the value of the denominator. -@item -fspeculative-prefetching -@opindex fspeculative-prefetching -If combined with @option{-fprofile-arcs}, it instructs the compiler to add -a code to gather information about addresses of memory references in the -program. - -With @option{-fbranch-probabilities}, it reads back the data gathered -and issues prefetch instructions according to them. In addition to the opportunities -noticed by @option{-fprefetch-loop-arrays}, it also notices more complicated -memory access patterns---for example accesses to the data stored in linked -list whose elements are usually allocated sequentially. - -In order to prevent issuing double prefetches, usage of -@option{-fspeculative-prefetching} implies @option{-fno-prefetch-loop-arrays}. - -Enabled with @option{-fprofile-generate} and @option{-fprofile-use}. - @item -frename-registers @opindex frename-registers Attempt to avoid false dependencies in scheduled code by making use @@ -5639,6 +5646,17 @@ threading. When performing branch target register load optimization, don't reuse branch target registers in within any basic block. +@item -fstack-protector +Emit extra code to check for buffer overflows, such as stack smashing +attacks. This is done by adding a guard variable to functions with +vulnerable objects. This includes functions that call alloca, and +functions with buffers larger than 8 bytes. The guards are initialized +when a function is entered and then checked when the function exits. +If a guard check fails, an error message is printed and the program exits. + +@item -fstack-protector-all +Like @option{-fstack-protector} except that all functions are protected. + @item --param @var{name}=@var{value} @opindex param In some places, GCC uses various constants to control the amount of @@ -5783,6 +5801,18 @@ happens only when @option{-finline-functions} (included in @option{-O3}) is enabled and @option{--param max-inline-recursive-depth-auto} is used. The default value is 450. +@item min-inline-recursive-probability +Recursive inlining is profitable only for function having deep recursion +in average and can hurt for function having little recursion depth by +increasing the prologue size or complexity of function body to other +optimizers. + +When profile feedback is available (see @option{-fprofile-generate}) the actual +recursion depth can be guessed from probability that function will recurse via +given call expression. This parameter limits inlining only to call expression +whose probability exceeds given threshold (in percents). The default value is +10. + @item inline-call-cost Specify cost of call instruction relative to simple arithmetics operations (having cost of 1). Increasing this cost disqualifies inlining of non-leaf @@ -5979,6 +6009,10 @@ interblock scheduling. The default value is 10. The maximum number of insns in a region to be considered for interblock scheduling. The default value is 100. +@item min-sched-prob +The minimum probability of reaching a source block for interblock +speculative scheduling. The default value is 40. + @item max-last-value-rtl The maximum size measured as number of RTLs that can be recorded in an expression @@ -6002,6 +6036,10 @@ than the number of virtual symbols to be updated, then the incremental SSA updater switches to a full update for those symbols. The default ratio is 3. +@item ssp-buffer-size +The minimum size of buffers (i.e. arrays) that will receive stack smashing +protection when @option{-fstack-protection} is used. + @end table @end table @@ -6183,6 +6221,14 @@ For predictable results, you must also specify the same set of options that were used to generate code (@option{-fpie}, @option{-fPIE}, or model suboptions) when you specify this option. +@item -rdynamic +@opindex rdynamic +Pass the flag @option{-export-dynamic} to the ELF linker, on targets +that support it. This instructs the linker to add all symbols, not +only used ones, to the dynamic symbol table. This option is needed +for some uses of @code{dlopen} or to allow obtaining backtraces +from within a program. + @item -s @opindex s Remove all symbol table and relocation information from the executable. @@ -6934,14 +6980,16 @@ The argument @var{machine} specifies the target machine for compilation. The value to use for @var{machine} is the same as was specified as the machine type when configuring GCC as a cross-compiler. For example, if a cross-compiler was configured with @samp{configure -i386v}, meaning to compile for an 80386 running System V, then you -would specify @option{-b i386v} to run that cross compiler. +arm-elf}, meaning to compile for an arm processor with elf binaries, +then you would specify @option{-b arm-elf} to run that cross compiler. +Because there are other options beginning with @option{-b}, the +configuration must contain a hyphen. @item -V @var{version} @opindex V The argument @var{version} specifies which version of GCC to run. This is useful when multiple versions are installed. For example, -@var{version} might be @samp{2.0}, meaning to run GCC version 2.0. +@var{version} might be @samp{4.0}, meaning to run GCC version 4.0. @end table The @option{-V} and @option{-b} options work by running the @@ -6980,6 +7028,7 @@ platform. * AVR Options:: * Blackfin Options:: * CRIS Options:: +* CRX Options:: * Darwin Options:: * DEC Alpha Options:: * DEC Alpha/VMS Options:: @@ -6996,6 +7045,7 @@ platform. * MIPS Options:: * MMIX Options:: * MN10300 Options:: +* MS1 Options:: * PDP-11 Options:: * PowerPC Options:: * RS/6000 and PowerPC Options:: @@ -7651,6 +7701,24 @@ Like @option{-sim}, but pass linker options to locate initialized data at 0x40000000 and zero-initialized data at 0x80000000. @end table +@node CRX Options +@subsection CRX Options +@cindex CRX Options + +These options are defined specifically for the CRX ports. + +@table @gcctabopt + +@item -mmac +@opindex mmac +Enable the use of multiply-accumulate instructions. Disabled by default. + +@item -mpush-args +@opindex mpush-args +Push instructions will be used to pass outgoing arguments when functions +are called. Enabled by default. +@end table + @node Darwin Options @subsection Darwin Options @cindex Darwin options @@ -8520,6 +8588,18 @@ Disable nested conditional execution optimizations. This switch is mainly for debugging the compiler and will likely be removed in a future version. +@item -moptimize-membar +@opindex moptimize-membar + +This switch removes redundant @code{membar} instructions from the +compiler generated code. It is enabled by default. + +@item -mno-optimize-membar +@opindex mno-optimize-membar + +This switch disables the automatic removal of redundant @code{membar} +instructions from the generated code. + @item -mtomcat-stats @opindex mtomcat-stats @@ -8709,7 +8789,8 @@ have any affect on which ld is called, it only changes what parameters are passed to that ld. The ld that is called is determined by the @option{--with-ld} configure option, GCC's program search path, and finally by the user's @env{PATH}. The linker used by GCC can be printed -using @samp{which `gcc -print-prog-name=ld`}. +using @samp{which `gcc -print-prog-name=ld`}. This option is only available +on the 64 bit HP-UX GCC, i.e. configured with @samp{hppa*64*-*-hpux*}. @item -mhp-ld @opindex hp-ld @@ -8721,7 +8802,8 @@ which ld is called, it only changes what parameters are passed to that ld. The ld that is called is determined by the @option{--with-ld} configure option, GCC's program search path, and finally by the user's @env{PATH}. The linker used by GCC can be printed using @samp{which -`gcc -print-prog-name=ld`}. +`gcc -print-prog-name=ld`}. This option is only available on the 64 bit +HP-UX GCC, i.e. configured with @samp{hppa*64*-*-hpux*}. @item -mlong-calls @opindex mno-long-calls @@ -9033,6 +9115,11 @@ their size as well as function calling convention for function taking @code{long double} will be modified. Hence they will not be binary compatible with arrays or structures in code compiled without that switch. +@item -mmlarge-data-threshold=@var{number} +@opindex mlarge-data-threshold=@var{number} +When @option{-mcmodel=medium} is specified, the data greater than +@var{threshold} are placed in large data section. This value must be the +same across all object linked into the binary and defaults to 65535. @item -msvr3-shlib @itemx -mno-svr3-shlib @@ -9904,13 +9991,17 @@ The ISA names are: @samp{mips1}, @samp{mips2}, @samp{mips3}, @samp{mips4}, @samp{mips32}, @samp{mips32r2}, and @samp{mips64}. The processor names are: -@samp{4kc}, @samp{4kp}, @samp{5kc}, @samp{20kc}, +@samp{4kc}, @samp{4km}, @samp{4kp}, +@samp{5kc}, @samp{5kf}, +@samp{20kc}, +@samp{24k}, @samp{24kc}, @samp{24kf}, @samp{24kx}, @samp{m4k}, -@samp{r2000}, @samp{r3000}, @samp{r3900}, @samp{r4000}, @samp{r4400}, -@samp{r4600}, @samp{r4650}, @samp{r6000}, @samp{r8000}, @samp{rm7000}, -@samp{rm9000}, @samp{orion}, +@samp{r2000}, @samp{r3000}, @samp{r3900}, @samp{r4000}, @samp{r4400}, +@samp{r4600}, @samp{r4650}, @samp{r6000}, @samp{r8000}, +@samp{rm7000}, @samp{rm9000}, @samp{sb1}, +@samp{sr71000}, @samp{vr4100}, @samp{vr4111}, @samp{vr4120}, @samp{vr4130}, @samp{vr4300}, @samp{vr5000}, @samp{vr5400} and @samp{vr5500}. The special value @samp{from-abi} selects the @@ -10471,6 +10562,52 @@ has an effect when used on the command line for the final link step. This option makes symbolic debugging impossible. @end table +@node MS1 Options +@subsection MS1 Options +@cindex MS1 options + +These @option{-m} options are defined for Morpho MS1 architectures: + +@table @gcctabopt + +@item -march=@var{cpu-type} +@opindex march +Generate code that will run on @var{cpu-type}, which is the name of a system +representing a certain processor type. Possible values for +@var{cpu-type} are @samp{MS1-64-001}, @samp{MS1-16-002}, and +@samp{MS1-16-003}. + +When this option is not used, the default is @option{-march=MS1-16-003}. + +@item -mmul +@opindex mmul +Generate multiply instructions. + +@item -mno-mul +@opindex mno-mul +Do not generate multiply instructions. + +@item -mbacc +@opindex mbacc +Use byte loads and stores when generating code. + +@item -mno-bacc +@opindex mno-bacc +Do not use byte loads and stores when generating code. + +@item -msim +@opindex msim +Use simulator runtime + +@item -mno-crt0 +@opindex mno-crt0 +Do not link in the C run-time initialization object file +@file{crti.o}. Other run-time initialisation and termination files +such as @file{startup.o} and @file{exit.o} are still included on the +linker command line. + +@end table + @node PDP-11 Options @subsection PDP-11 Options @cindex PDP-11 Options @@ -13110,9 +13247,9 @@ which options are safe to change and which are not; the safest choice is to use exactly the same options when generating and using the precompiled header. The following are known to be safe: -@gccoptlist{-fpreprocessed +@gccoptlist{-fmessage-length= -fpreprocessed -fsched-interblock -fsched-spec -fsched-spec-load -fsched-spec-load-dangerous --fsched-verbose=<number> -fschedule-insns +-fsched-verbose=<number> -fschedule-insns -fvisibility= -pedantic-errors} @end itemize |