@item Overall Options
@xref{Overall Options,,Options Controlling the Kind of Output}.
@gccoptlist{-c -S -E -o @var{file} -combine -pipe -pass-exit-codes @gol
--x @var{language} -v -### --help@r{[}=@var{class}@r{]} --target-help @gol
+-x @var{language} -v -### --help@r{[}=@var{class}@r{[},@dots{}@r{]]} --target-help @gol
--version -wrapper@@@var{file}}
@item C Language Options
@emph{DEC Alpha/VMS Options}
@gccoptlist{-mvms-return-codes}
+@emph{FR30 Options}
+@gccoptlist{-msmall-model -mno-lsim}
+
@emph{FRV Options}
@gccoptlist{-mgpr-32 -mgpr-64 -mfpr-32 -mfpr-64 @gol
-mhard-float -msoft-float @gol
line options for each tool. For some targets extra target-specific
information may also be printed.
-@item --help=@var{class}@r{[},@var{qualifier}@r{]}
+@item --help=@{@var{class}@r{|[}^@r{]}@var{qualifier}@}@r{[},@dots{}@r{]}
Print (on the standard output) a description of the command line
-options understood by the compiler that fit into a specific class.
-The class can be one of @samp{optimizers}, @samp{warnings}, @samp{target},
-@samp{params}, or @var{language}:
+options understood by the compiler that fit into all specified classes
+and qualifiers. These are the supported classes:
@table @asis
@item @samp{optimizers}
This will display the options that are common to all languages.
@end table
-It is possible to further refine the output of the @option{--help=}
-option by adding a comma separated list of qualifiers after the
-class. These can be any from the following list:
+These are the supported qualifiers:
@table @asis
@item @samp{undocumented}
@end smallexample
The sense of a qualifier can be inverted by prefixing it with the
-@var{^} character, so for example to display all binary warning
+@samp{^} character, so for example to display all binary warning
options (i.e., ones that are either on or off and that do not take an
argument), which have a description the following can be used:
--help=warnings,^joined,^undocumented
@end smallexample
-A class can also be used as a qualifier, although this usually
+The argument to @option{--help=} should not consist solely of inverted
+qualifiers.
+
+Combining several classes is possible, although this usually
restricts the output by so much that there is nothing to display. One
case where it does work however is when one of the classes is
@var{target}. So for example to display all the target-specific
are enabled at @option{-O2} by using:
@smallexample
--O2 --help=optimizers
+-Q -O2 --help=optimizers
@end smallexample
Alternatively you can discover which binary optimizations are enabled
enumeration. @code{case} labels outside the enumeration range also
provoke warnings when this option is used.
-@item -Wsync-nand
+@item -Wsync-nand @r{(C and C++ only)}
@opindex Wsync-nand
@opindex Wno-sync-nand
Warn when @code{__sync_fetch_and_nand} and @code{__sync_nand_and_fetch}
@option{-funsafe-loop-optimizations} warn if the compiler made
such assumptions.
-@item -Wno-pedantic-ms-format
+@item -Wno-pedantic-ms-format @r{(MinGW targets only)}
@opindex Wno-pedantic-ms-format
@opindex Wpedantic-ms-format
Disables the warnings about non-ISO @code{printf} / @code{scanf} format
@item -fno-merge-debug-strings
@opindex fmerge-debug-strings
@opindex fno-merge-debug-strings
-Direct the linker to merge together strings which are identical in
-different object files. This is not supported by all assemblers or
-linker. This decreases the size of the debug information in the
-output file at the cost of increasing link processing time. This is
-on by default.
+Direct the linker to not merge together strings in the debugging
+information which are identical in different object files. Merging is
+not supported by all assemblers or linkers. Merging decreases the size
+of the debug information in the output file at the cost of increasing
+link processing time. Merging is enabled by default.
@item -fdebug-prefix-map=@var{old}=@var{new}
@opindex fdebug-prefix-map
@item -fdump-rtl-compgotos
@opindex fdump-rtl-compgotos
-Dump after dumplicating the computed gotos.
+Dump after duplicating the computed gotos.
@item -fdump-rtl-ce1
@itemx -fdump-rtl-ce2
with its equivalent n-dimensional matrix, where n < m.
This reduces the level of indirection needed for accessing the elements
of the matrix. The second optimization is matrix transposing that
-attemps to change the order of the matrix's dimensions in order to
+attempts to change the order of the matrix's dimensions in order to
improve cache locality.
Both optimizations need the @option{-fwhole-program} flag.
Transposing is enabled only if profiling information is available.
supply system-specific linker options which GCC does not know how to
recognize.
-If you want to pass an option that takes an argument, you must use
+If you want to pass an option that takes a separate argument, you must use
@option{-Xlinker} twice, once for the option and once for the argument.
For example, to pass @option{-assert definitions}, you must write
@samp{-Xlinker -assert -Xlinker definitions}. It does not work to write
@option{-Xlinker "-assert definitions"}, because this passes the entire
string as a single argument, which is not what the linker expects.
+When using the GNU linker, it is usually more convenient to pass
+arguments to linker options using the @option{@var{option}=@var{value}}
+syntax than as separate arguments. For example, you can specify
+@samp{-Xlinker -Map=output.map} rather than
+@samp{-Xlinker -Map -Xlinker output.map}. Other linkers may not support
+this syntax for command-line options.
+
@item -Wl,@var{option}
@opindex Wl
Pass @var{option} as an option to the linker. If @var{option} contains
-commas, it is split into multiple options at the commas.
+commas, it is split into multiple options at the commas. You can use this
+syntax to pass an argument to the option.
+For example, @samp{-Wl,-Map,output.map} passes @samp{-Map output.map} to the
+linker. When using the GNU linker, you can also get the same effect with
+@samp{-Wl,-Map=output.map}.
@item -u @var{symbol}
@opindex u
* Darwin Options::
* DEC Alpha Options::
* DEC Alpha/VMS Options::
+* FR30 Options::
* FRV Options::
* GNU/Linux Options::
* H8/300 Options::
Schedules as an EV6 and supports the BWX, CIX, FIX, and MAX extensions.
@end table
+Native Linux/GNU toolchains also support the value @samp{native},
+which selects the best architecture option for the host processor.
+@option{-mcpu=native} has no effect if GCC does not recognize
+the processor.
+
@item -mtune=@var{cpu_type}
@opindex mtune
Set only the instruction scheduling parameters for machine type
@var{cpu_type}. The instruction set is not changed.
+Native Linux/GNU toolchains also support the value @samp{native},
+which selects the best architecture option for the host processor.
+@option{-mtune=native} has no effect if GCC does not recognize
+the processor.
+
@item -mmemory-latency=@var{time}
@opindex mmemory-latency
Sets the latency the scheduler should assume for typical memory
style condition (e.g.@: error) codes.
@end table
+@node FR30 Options
+@subsection FR30 Options
+@cindex FR30 Options
+
+These options are defined specifically for the FR30 port.
+
+@table @gcctabopt
+
+@item -msmall-model
+@opindex msmall-model
+Use the small address space model. This can produce smaller code, but
+it does assume that all symbolic values and addresses will fit into a
+20-bit range.
+
+@item -mno-lsim
+@opindex mno-lsim
+Assume that run-time support has been provided and so there is no need
+to include the simulator library (@file{libsim.a}) on the linker
+command line.
+
+@end table
+
@node FRV Options
@subsection FRV Options
@cindex FRV Options
@item -mrecip
@opindex mrecip
This option will enable GCC to use RCPSS and RSQRTSS instructions (and their
-vectorized variants RCPPS and RSQRTPS) with an additional Newton-Rhapson step
+vectorized variants RCPPS and RSQRTPS) with an additional Newton-Raphson step
to increase precision instead of DIVSS and SQRTSS (and their vectorized
variants) for single precision floating point arguments. These instructions
are generated only when @option{-funsafe-math-optimizations} is enabled
@opindex m210
@opindex m340
Generate code for the 210 processor.
+
+@item -mno-lsim
+@opindex no-lsim
+Assume that run-time support has been provided and so omit the
+simulator library (@file{libsim.a)} from the linker command line.
+
+@item -mstack-increment=@var{size}
+@opindex mstack-increment
+Set the maximum amount for a single stack increment operation. Large
+values can increase the speed of programs which contain functions
+that need a large amount of stack space, but they can also trigger a
+segmentation fault if the stack is extended too much. The default
+value is 0x1000.
+
@end table
@node MIPS Options
compile code the same as @option{-msdata=eabi}, otherwise compile code the
same as @option{-msdata=sysv}.
-@item -msdata-data
-@opindex msdata-data
+@item -msdata=data
+@opindex msdata=data
On System V.4 and embedded PowerPC systems, put small global
data in the @samp{.sdata} section. Put small uninitialized global
data in the @samp{.sbss} section. Do not use register @code{r13}
@item -fno-common
@opindex fno-common
-In C, allocate even uninitialized global variables in the data section of the
-object file, rather than generating them as common blocks. This has the
-effect that if the same variable is declared (without @code{extern}) in
-two different compilations, you will get an error when you link them.
-The only reason this might be useful is if you wish to verify that the
-program will work on other systems which always work this way.
+In C code, controls the placement of uninitialized global variables.
+Unix C compilers have traditionally permitted multiple definitions of
+such variables in different compilation units by placing the variables
+in a common block.
+This is the behavior specified by @option{-fcommon}, and is the default
+for GCC on most targets.
+On the other hand, this behavior is not required by ISO C, and on some
+targets may carry a speed or code size penalty on variable references.
+The @option{-fno-common} option specifies that the compiler should place
+uninitialized global variables in the data section of the object file,
+rather than generating them as common blocks.
+This has the effect that if the same variable is declared
+(without @code{extern}) in two different compilations,
+you will get a multiple-definition error when you link them.
+In this case, you must compile with @option{-fcommon} instead.
+Compiling with @option{-fno-common} is useful on targets for which
+it provides better performance, or if you wish to verify that the
+program will work on other systems which always treat uninitialized
+variable declarations this way.
@item -fno-ident
@opindex fno-ident
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