@xref{C Dialect Options,,Options Controlling C Dialect}.
@smallexample
-ansi -fallow-single-precision -fcond-mismatch -fno-asm
--fno-builtin -ffreestanding - fhosted -fsigned-bitfields -fsigned-char
+-fno-builtin -ffreestanding -fhosted -fsigned-bitfields -fsigned-char
-funsigned-bitfields -funsigned-char -fwritable-strings
-traditional -traditional-cpp -trigraphs
@end smallexample
@xref{C++ Dialect Options,,Options Controlling C++ Dialect}.
@smallexample
-fall-virtual -fdollars-in-identifiers -felide-constructors
--fenum-int-equiv -fexternal-templates -ffor-scope -fno-for-scope
--fhandle-signatures -fmemoize-lookups -fno-default-inline -fno-gnu-keywords
--fnonnull-objects -foperator-names -fstrict-prototype -fthis-is-variable
--ftemplate-depth-@var{n} -nostdinc++ -traditional +e@var{n}
+-fenum-int-equiv -fexternal-templates -ffor-scope -fno-for-scope
+-fhandle-signatures -fmemoize-lookups -fname-mangling-version-@var{n}
+-fno-default-inline -fno-gnu-keywords -fnonnull-objects -fguiding-decls
+-foperator-names -fstrict-prototype -fthis-is-variable
+-ftemplate-depth-@var{n} -nostdinc++ -traditional +e@var{n}
@end smallexample
@item Warning Options
@smallexample
-fsyntax-only -pedantic -pedantic-errors
-w -W -Wall -Waggregate-return -Wbad-function-cast
--Wcast-align -Wcast-qual -Wchar-subscript -Wcomment
+-Wcast-align -Wcast-qual -Wchar-subscript -Wcomment
-Wconversion -Werror -Wformat
--Wid-clash-@var{len} -Wimplicit -Wimport -Winline
+-Wid-clash-@var{len} -Wimplicit -Wimplicit-int
+-Wimplicit-function-declarations -Wimport -Winline
-Wlarger-than-@var{len} -Wmain -Wmissing-declarations
-Wmissing-prototypes -Wnested-externs
--Wno-import -Woverloaded-virtual -Wparentheses
--Wpointer-arith -Wredundant-decls -Wreorder -Wreturn-type -Wshadow
--Wsign-compare -Wstrict-prototypes -Wswitch -Wsynth
+-Wno-import -Wold-style-cast -Woverloaded-virtual -Wparentheses
+-Wpointer-arith -Wredundant-decls -Wreorder -Wreturn-type -Wshadow
+-Wsign-compare -Wstrict-prototypes -Wswitch -Wsynth
-Wtemplate-debugging -Wtraditional -Wtrigraphs
--Wundef -Wuninitialized -Wunused -Wwrite-strings
+-Wundef -Wuninitialized -Wunused -Wwrite-strings
@end smallexample
@item Debugging Options
@smallexample
-a -ax -d@var{letters} -fpretend-float
-fprofile-arcs -ftest-coverage
--g -g@var{level} -gcoff -gdwarf -gdwarf-1 -gdwarf-1+ -gdwarf-2
+-g -g@var{level} -gcoff -gdwarf -gdwarf-1 -gdwarf-1+ -gdwarf-2
-ggdb -gstabs -gstabs+ -gxcoff -gxcoff+
-p -pg -print-file-name=@var{library} -print-libgcc-file-name
-print-prog-name=@var{program} -print-search-dirs -save-temps
-fcaller-saves -fcse-follow-jumps -fcse-skip-blocks
-fdelayed-branch -fexpensive-optimizations
-ffast-math -ffloat-store -fforce-addr -fforce-mem
--ffunction-sections -finline-functions
--fkeep-inline-functions -fno-default-inline
+-ffunction-sections -finline-functions
+-fkeep-inline-functions -fno-default-inline
-fno-defer-pop -fno-function-cse
-fno-inline -fno-peephole -fomit-frame-pointer -fregmove
--frerun-cse-after-loop -fschedule-insns
+-frerun-cse-after-loop -frerun-loop-opt -fschedule-insns
-fschedule-insns2 -fstrength-reduce -fthread-jumps
-funroll-all-loops -funroll-loops
-fmove-all-movables -freduce-all-givs
@item Directory Options
@xref{Directory Options,,Options for Directory Search}.
@smallexample
--B@var{prefix} -I@var{dir} -I- -L@var{dir} -specs=@var{file}
+-B@var{prefix} -I@var{dir} -I- -L@var{dir} -specs=@var{file}
@end smallexample
@item Target Options
@xref{Submodel Options,,Hardware Models and Configurations}.
@smallexample
@emph{M680x0 Options}
--m68000 -m68020 -m68020-40 -m68020-60 -m68030 -m68040
--m68060 -m5200 -m68881 -mbitfield -mc68000 -mc68020 -mfpa
+-m68000 -m68020 -m68020-40 -m68020-60 -m68030 -m68040
+-m68060 -m5200 -m68881 -mbitfield -mc68000 -mc68020 -mfpa
-mnobitfield -mrtd -mshort -msoft-float -malign-int
@emph{VAX Options}
-mg -mgnu -munix
@emph{SPARC Options}
--mcpu=@var{cpu type}
--mtune=@var{cpu type}
+-mcpu=@var{cpu type}
+-mtune=@var{cpu type}
+-mcmodel=@var{code model}
+-malign-jumps=@var{num} -malign-loops=@var{num}
+-malign-functions=@var{num}
+-m32 -m64
-mapp-regs -mbroken-saverestore -mcypress -mepilogue
--mflat -mfpu -mfullany -mhard-float -mhard-quad-float
--mimpure-text -mint32 -mint64 -mlive-g0
--mlong32 -mlong64 -mmedlow -mmedany
--mno-app-regs -mno-epilogue
+-mflat -mfpu -mhard-float -mhard-quad-float
+-mimpure-text -mlive-g0 -mno-app-regs -mno-epilogue
-mno-flat -mno-fpu -mno-impure-text
-mno-stack-bias -mno-unaligned-doubles
-msoft-float -msoft-quad-float -msparclite -mstack-bias
-mstorem-bug -muser-registers
@emph{ARM Options}
--mapcs-frame -mapcs-26 -mapcs-32
--mlittle-endian -mbig-endian -mwords-little-endian
--mshort-load-bytes -mno-short-load-bytes
--msoft-float -mhard-float
--mbsd -mxopen -mno-symrename
+-mapcs-frame -mapcs-26 -mapcs-32
+-mlittle-endian -mbig-endian -mwords-little-endian
+-mshort-load-bytes -mno-short-load-bytes
+-msoft-float -mhard-float
+-mbsd -mxopen -mno-symrename
+
+@emph{MN10300 Options}
+-mmult-bug
+-mno-mult-bug
@emph{M32R/D Options}
-mcode-model=@var{model type} -msdata=@var{sdata type}
-mversion-03.00 -mwarn-passed-structs
@emph{RS/6000 and PowerPC Options}
--mcpu=@var{cpu type}
--mtune=@var{cpu type}
+-mcpu=@var{cpu type}
+-mtune=@var{cpu type}
-mpower -mno-power -mpower2 -mno-power2
-mpowerpc -mno-powerpc
-mpowerpc-gpopt -mno-powerpc-gpopt
-mtoc -mno-toc -mtraceback -mno-traceback
-mlittle -mlittle-endian -mbig -mbig-endian
-mcall-aix -mcall-sysv -mprototype -mno-prototype
--msim -mmvme -memb -msdata -msdata=@var{opt} -G @var{num}
+-msim -mmvme -mads -myellowknife -memb
+-msdata -msdata=@var{opt} -G @var{num}
@emph{RT Options}
-mcall-lib-mul -mfp-arg-in-fpregs -mfp-arg-in-gregs
-mminimum-fp-blocks -mnohc-struct-return
@emph{MIPS Options}
--mabicalls -mcpu=@var{cpu type} -membedded-data
+-mabicalls -mcpu=@var{cpu type} -membedded-data
-membedded-pic -mfp32 -mfp64 -mgas -mgp32 -mgp64
--mgpopt -mhalf-pic -mhard-float -mint64 -mips1
--mips2 -mips3 -mlong64 -mlong-calls -mmemcpy
+-mgpopt -mhalf-pic -mhard-float -mint64 -mips1
+-mips2 -mips3 -mlong64 -mlong-calls -mmemcpy
-mmips-as -mmips-tfile -mno-abicalls
-mno-embedded-data -mno-embedded-pic
-mno-gpopt -mno-long-calls
-mno-memcpy -mno-mips-tfile -mno-rnames -mno-stats
--mrnames -msoft-float
--m4650 -msingle-float -mmad
+-mrnames -msoft-float
+-m4650 -msingle-float -mmad
-mstats -EL -EB -G @var{num} -nocpp
@emph{i386 Options}
--m486 -m386 -mieee-fp -mno-fancy-math-387
+-mcpu=@var{cpu type}
+-march=@var{cpu type}
+-mieee-fp -mno-fancy-math-387
-mno-fp-ret-in-387 -msoft-float -msvr3-shlib
--mno-wide-multiply -mrtd -malign-double
--mreg-alloc=@var{list} -mregparm=@var{num}
--malign-jumps=@var{num} -malign-loops=@var{num}
+-mno-wide-multiply -mrtd -malign-double
+-mreg-alloc=@var{list} -mregparm=@var{num}
+-malign-jumps=@var{num} -malign-loops=@var{num}
-malign-functions=@var{num}
@emph{HPPA Options}
--mbig-switch -mdisable-fpregs -mdisable-indexing -mfast-indirect-calls
--mgas -mjump-in-delay -mlong-load-store -mno-big-switch -mno-disable-fpregs
--mno-disable-indexing -mno-fast-indirect-calls -mno-gas
+-mbig-switch -mdisable-fpregs -mdisable-indexing -mfast-indirect-calls
+-mgas -mjump-in-delay -mlong-load-store -mno-big-switch -mno-disable-fpregs
+-mno-disable-indexing -mno-fast-indirect-calls -mno-gas
-mno-jump-in-delay
-mno-long-load-store
--mno-portable-runtime -mno-soft-float -mno-space -mno-space-regs -msoft-float
+-mno-portable-runtime -mno-soft-float -mno-space -mno-space-regs
+-msoft-float
-mpa-risc-1-0 -mpa-risc-1-1 -mportable-runtime
--mschedule=@var{list} -mspace -mspace-regs
+-mschedule=@var{list} -mspace -mspace-regs
@emph{Intel 960 Options}
-m@var{cpu type} -masm-compat -mclean-linkage
-mtail-call
@emph{DEC Alpha Options}
--mfp-regs -mno-fp-regs
--mno-soft-float -msoft-float
--mieee -mieee-with-inexact -mieee-conformant
--mfp-trap-mode -mfp-rounding-mode -mtrap-precision
--mbuild-constants
+-mfp-regs -mno-fp-regs -mno-soft-float -msoft-float
+-malpha-as -mgas
+-mieee -mieee-with-inexact -mieee-conformant
+-mfp-trap-mode=@var{mode} -mfp-rounding-mode=@var{mode}
+-mtrap-precision=@var{mode} -mbuild-constants
+-mcpu=@var{cpu type}
+-mbwx -mno-bwx -mcix -mno-cix -mmax -mno-max
@emph{Clipper Options}
--mc300 -mc400
+-mc300 -mc400
@emph{H8/300 Options}
--mrelax -mh -mint32 -malign-300
+-mrelax -mh -ms -mint32 -malign-300
@emph{SH Options}
-m1 -m2 -m3 -m3e -mb -ml -mrelax
@emph{System V Options}
-Qy -Qn -YP,@var{paths} -Ym,@var{dir}
+
+@emph{V850 Options}
+-mlong-calls -mno-long-calls -mep -mno-ep
+-mprolog-function -mno-prolog-function -mspace
+-mtda=@var{n} -msda=@var{n} -mzda=@var{n}
+-mv850 -mbig-switch
@end smallexample
@item Code Generation Options
@xref{Code Gen Options,,Options for Code Generation Conventions}.
@smallexample
-fcall-saved-@var{reg} -fcall-used-@var{reg}
--ffixed-@var{reg} -finhibit-size-directive
+-fexceptions -ffixed-@var{reg} -finhibit-size-directive
-fcheck-memory-usage -fprefix-function-name
-fno-common -fno-ident -fno-gnu-linker
-fpcc-struct-return -fpic -fPIC
to the location of the template definition. @xref{Template
Instantiation}, for more information.
+This option is deprecated.
+
@item -falt-external-templates
Similar to -fexternal-templates, but template instances are emitted or
not according to the place where they are first instantiated.
@xref{Template Instantiation}, for more information.
+This option is deprecated.
+
@item -ffor-scope
-@item -fno-for-scope
+@itemx -fno-for-scope
If -ffor-scope is specified, the scope of variables declared in
a @i{for-init-statement} is limited to the @samp{for} loop itself,
as specified by the draft C++ standard.
@code{__typeof__} instead. @samp{-ansi} implies
@samp{-fno-gnu-keywords}.
+@item -fguiding-decls
+Treat a function declaration with the same type as a potential function
+template instantiation as though it declares that instantiation, not a
+normal function. If a definition is given for the function later in the
+translation unit (or another translation unit if the target supports
+weak symbols), that definition will be used; otherwise the template will
+be instantiated. This behavior reflects the C++ language prior to
+September 1996, when guiding declarations were removed.
+
+This option implies @samp{-fname-mangling-version-0}, and will not work
+with other name mangling versions.
+
@item -fno-implicit-templates
Never emit code for templates which are instantiated implicitly (i.e. by
use); only emit code for explicit instantiations. @xref{Template
This flag no longer affects declarations with C++ linkage.
+@item -fname-mangling-version-@var{n}
+Control the way in which names are mangled. Version 0 is compatible
+with versions of g++ before 2.8. Version 1 is the default. Version 1
+will allow correct mangling of function templates. For example,
+version 0 mangling does not mangle foo<int, double> and foo<int, char>
+given this declaration:
+
+@example
+template <class T, class U> void foo(T t);
+@end example
+
@item -fno-nonnull-objects
Don't assume that a reference is initialized to refer to a valid object.
Although the current C++ Working Paper prohibits null references, some
synonyms for the symbols they refer to. @samp{-ansi} implies
@samp{-foperator-names}.
+@item -frepo
+Enable automatic template instantiation. This option also implies
+@samp{-fno-implicit-templates}. @xref{Template Instantiation}, for more
+information.
+
@item -fthis-is-variable
Permit assignment to @code{this}. The incorporation of user-defined
free store management into C++ has made assignment to @samp{this} an
Do not assume @samp{inline} for functions defined inside a class scope.
@xref{Optimize Options,,Options That Control Optimization}.
-@item -Woverloaded-virtual
+@item -Wold-style-cast
+@itemx -Woverloaded-virtual
@itemx -Wtemplate-debugging
Warnings that apply only to C++ programs. @xref{Warning
Options,,Options to Request or Suppress Warnings}.
the arguments supplied have types appropriate to the format string
specified.
+@item -Wimplicit-int
+Warn when a declaration does not specify a type.
+
+@item -Wimplicit-function-declarations
+Warn whenever a function is used before being declared.
+
@item -Wimplicit
-Warn whenever a function or parameter is implicitly declared,
-or when a type implicitly defaults to @code{int}.
+Same as @samp{-Wimplicit-int} @samp{-Wimplicit-function-declaration}.
@item -Wmain
Warn if the type of @samp{main} is suspicious. @samp{main} should be a
is expected, or when operators are nested whose precedence people
often get confused about.
+Also warn about constructions where there may be confusion to which
+@code{if} statement an @code{else} branch belongs. Here is an example of
+such a case:
+
+@smallexample
+@{
+ if (a)
+ if (b)
+ foo ();
+ else
+ bar ();
+@}
+@end smallexample
+
+In C, every @code{else} branch belongs to the innermost possible @code{if}
+statement, which in this example is @code{if (b)}. This is often not
+what the programmer expected, as illustrated in the above example by
+indentation the programmer chose. When there is the potential for this
+confusion, GNU C will issue a warning when this flag is specified.
+To eliminate the warning, add explicit braces around the innermost
+@code{if} statement so there is no way the @code{else} could belong to
+the enclosing @code{if}. The resulting code would look like this:
+
+@smallexample
+@{
+ if (a)
+ @{
+ if (b)
+ foo ();
+ else
+ bar ();
+ @}
+@}
+@end smallexample
+
@item -Wreturn-type
Warn whenever a function is defined with a return-type that defaults
to @code{int}. Also warn about any @code{return} statement with no
label is declared but not used, and whenever a statement computes a
result that is explicitly not used.
+In order to get a warning about an unused function parameter, you must
+specify both @samp{-W} and @samp{-Wunused}.
+
To suppress this warning for an expression, simply cast it to void. For
unused variables and parameters, use the @samp{unused} attribute
(@pxref{Variable Attributes}).
and @samp{j} will be rearranged to match the declaration order of the
members.
-@item -Wsign-compare
-@cindex warning for comparison of signed and unsigned values
-@cindex comparison of signed and unsigned values, warning
-@cindex signed and unsigned values, comparison warning
-Warn when a comparison between signed and unsigned values could produce
-an incorrect result when the signed value is converted to unsigned.
-
@item -Wtemplate-debugging
@cindex template debugging
When using templates in a C++ program, warn if debugging is not yet
arguments.
@item
+A comparison between signed and unsigned values could produce an
+incorrect result when the signed value is converted to unsigned.
+(But do not warn if @samp{-Wno-sign-compare} is also specified.)
+
+@item
An aggregate has a partly bracketed initializer.
For example, the following code would evoke such a warning,
because braces are missing around the initializer for @code{x.h}:
@code{x = -1} if @code{x} is unsigned. But do not warn about explicit
casts like @code{(unsigned) -1}.
+@item -Wsign-compare
+@cindex warning for comparison of signed and unsigned values
+@cindex comparison of signed and unsigned values, warning
+@cindex signed and unsigned values, comparison warning
+Warn when a comparison between signed and unsigned values could produce
+an incorrect result when the signed value is converted to unsigned.
+This warning is also enabled by @samp{-W}; to get the other warnings
+of @samp{-W} without this warning, use @samp{-W -Wno-sign-compare}.
+
@item -Waggregate-return
Warn if any functions that return structures or unions are defined or
called. (In languages where you can return an array, this also elicits
Warn if a function can not be inlined, and either it was declared as inline,
or else the @samp{-finline-functions} option was given.
+@item -Wold-style-cast
+Warn if an old-style (C-style) cast is used within a program.
+
@item -Woverloaded-virtual
@cindex overloaded virtual fn, warning
@cindex warning for overloaded virtual fn
however, that the format of the data is not what @code{tcov} expects.
Eventually GNU @code{gprof} should be extended to process this data.
+@item -Q
+Makes the compiler print out each function name as it is compiled, and
+print some statistics about each pass when it finishes.
+
@item -ax
Generate extra code to profile basic blocks. Your executable will
produce output that is a superset of that produced when @samp{-a} is
The output is appended to file @file{bb.out}.
You can examine different profiling aspects without recompilation. Your
-execuable will read a list of function names from file @file{bb.in}.
+executable will read a list of function names from file @file{bb.in}.
Profiling starts when a function on the list is entered and stops when
that invocation is exited. To exclude a function from profiling, prefix
its name with `-'. If a function name is not unique, you can
@samp{-fprofile-arcs}).
@end table
+@item -Q
+Makes the compiler print out each function name as it is compiled, and
+print some statistics about each pass when it finishes.
+
@item -d@var{letters}
Says to make debugging dumps during compilation at times specified by
@var{letters}. This is used for debugging the compiler. The file names
@item s
Dump after CSE (including the jump optimization that sometimes
follows CSE), to @file{@var{file}.cse}.
+@item D
+Dump after purging ADDRESSOF, to @file{@var{file}.addressof}.
@item L
Dump after loop optimization, to @file{@var{file}.loop}.
@item t
Dump after the second CSE pass (including the jump optimization that
sometimes follows CSE), to @file{@var{file}.cse2}.
+@item b
+Dump after computing branch probabilities, to @file{@var{file}.bp}.
@item f
Dump after flow analysis, to @file{@var{file}.flow}.
@item c
Re-run common subexpression elimination after loop optimizations has been
performed.
+@item -frerun-loop-opt
+Run the loop optimizer twice.
+
@item -fexpensive-optimizations
Perform a number of minor optimizations that are relatively expensive.
they have helped determine the efficacy of various
approaches to improving loop optimizations.
-Please let us (@code{egcs@cygnus.com and fortran@@gnu.ai.mit.edu})
+Please let us (@code{egcs@@cygnus.com} and @code{fortran@@gnu.org})
know how use of these options affects
the performance of your production code.
We're very interested in code that runs @emph{slower}
* Convex Options::
* AMD29K Options::
* ARM Options::
+* MN10300 Options::
* M32R/D Options::
* M88K Options::
* RS/6000 and PowerPC Options::
* H8/300 Options::
* SH Options::
* System V Options::
+* V850 Options::
@end menu
@node M680x0 Options
They have been replaced with @samp{-mcpu=xxx}.
@item -mcpu=@var{cpu_type}
-Set architecture type and instruction scheduling parameters for machine
-type @var{cpu_type}. Supported values for @var{cpu_type} are
-@samp{common}, @samp{cypress}, @samp{v8}, @samp{supersparc},
-@samp{sparclite}, @samp{f930}, @samp{f934},
-@samp{sparclet}, @samp{90c701}, @samp{v8plus}, @samp{v9},
-and @samp{ultrasparc}. Specifying @samp{v9} is only supported on true
-64 bit targets.
+Set the instruction set, register set, and instruction scheduling parameters
+for machine type @var{cpu_type}. Supported values for @var{cpu_type} are
+@samp{v7}, @samp{cypress}, @samp{v8}, @samp{supersparc}, @samp{sparclite},
+@samp{f930}, @samp{f934}, @samp{sparclet}, @samp{tsc701}, @samp{v9}, and
+@samp{ultrasparc}.
+
+Default instruction scheduling parameters are used for values that select
+an architecture and not an implementation. These are @samp{v7}, @samp{v8},
+@samp{sparclite}, @samp{sparclet}, @samp{v9}.
+
+Here is a list of each supported architecture and their supported
+implementations.
+
+@smallexample
+ v7: cypress
+ v8: supersparc
+ sparclite: f930, f934
+ sparclet: tsc701
+ v9: ultrasparc
+@end smallexample
@item -mtune=@var{cpu_type}
Set the instruction scheduling parameters for machine type
-@var{cpu_type}, but do not set the architecture type as the option
-@samp{-mcpu=}@var{cpu_type} would. The same values for
-@samp{-mcpu=}@var{cpu_type} are used for @samp{-tune=}@var{cpu_type}.
+@var{cpu_type}, but do not set the instruction set or register set that the
+option @samp{-mcpu=}@var{cpu_type} would.
+
+The same values for @samp{-mcpu=}@var{cpu_type} are used for
+@samp{-mtune=}@var{cpu_type}, though the only useful values are those that
+select a particular cpu implementation: @samp{cypress}, @samp{supersparc},
+@samp{f930}, @samp{f934}, @samp{tsc701}, @samp{ultrasparc}.
+
+@item -malign-loops=@var{num}
+Align loops to a 2 raised to a @var{num} byte boundary. If
+@samp{-malign-loops} is not specified, the default is 2.
+
+@item -malign-jumps=@var{num}
+Align instructions that are only jumped to to a 2 raised to a @var{num}
+byte boundary. If @samp{-malign-jumps} is not specified, the default is 2.
+
+@item -malign-functions=@var{num}
+Align the start of functions to a 2 raised to @var{num} byte boundary.
+If @samp{-malign-functions} is not specified, the default is 2 if compiling
+for 32 bit sparc, and 5 if compiling for 64 bit sparc.
@end table
@item -mlittle-endian
Generate code for a processor running in little-endian mode.
-@item -mmedlow
-Generate code for the Medium/Low code model: assume a 32 bit address space.
-Programs are statically linked, PIC is not supported. Pointers are still
-64 bits.
-
-It is very likely that a future version of GCC will rename this option.
-
-@item -mmedany
-Generate code for the Medium/Anywhere code model: assume a 32 bit text
-and a 32 bit data segment, both starting anywhere (determined at link time).
-Programs are statically linked, PIC is not supported. Pointers are still
-64 bits.
-
-It is very likely that a future version of GCC will rename this option.
-
-@item -mfullany
-Generate code for the Full/Anywhere code model: assume a full 64 bit
-address space. PIC is not supported.
-
-It is very likely that a future version of GCC will rename this option.
-
-@item -mint64
-Types long and int are 64 bits.
-
-@item -mlong32
-Types long and int are 32 bits.
-
-@item -mlong64
-@itemx -mint32
-Type long is 64 bits, and type int is 32 bits.
+@item -m32
+@itemx -m64
+Generate code for a 32 bit or 64 bit environment.
+The 32 bit environment sets int, long and pointer to 32 bits.
+The 64 bit environment sets int to 32 bits and long and pointer
+to 64 bits.
+
+@item -mcmodel=medlow
+Generate code for the Medium/Low code model: the program must be linked
+in the low 32 bits of the address space. Pointers are 64 bits.
+Programs can be statically or dynamically linked.
+
+@item -mcmodel=medmid
+Generate code for the Medium/Middle code model: the program must be linked
+in the low 44 bits of the address space, the text segment must be less than
+2G bytes, and data segment must be within 2G of the text segment.
+Pointers are 64 bits.
+
+@item -mcmodel=medany
+Generate code for the Medium/Anywhere code model: the program may be linked
+anywhere in the address space, the text segment must be less than
+2G bytes, and data segment must be within 2G of the text segment.
+Pointers are 64 bits.
+
+@item -mcmodel=embmedany
+Generate code for the Medium/Anywhere code model for embedded systems:
+assume a 32 bit text and a 32 bit data segment, both starting anywhere
+(determined at link time). Register %g4 points to the base of the
+data segment. Pointers still 64 bits.
+Programs are statically linked, PIC is not supported.
@item -mstack-bias
@itemx -mno-stack-bias
compiler is built for cross-compilation.
@end table
+@node MN10300 Options
+@subsection MN10300 Options
+@cindex MN10300 options
+These @samp{-m} options are defined for Matsushita MN10300 architectures:
+
+@table @code
+@item -mmult-bug
+Generate code to avoid bugs in the multiply instructions for the MN10300
+processors. This is the default.
+
+@item -mno-mult-bug
+Do not generate code to avoid bugs in the multiply instructions for the
+MN10300 processors.
+@end table
+
@node M32R/D Options
@subsection M32R/D Options
@cindex M32R/D options
@itemx -mno-relocatable-lib
On embedded PowerPC systems generate code that allows (does not allow)
the program to be relocated to a different address at runtime. Modules
-compiled with @samp{-mreloctable-lib} can be linked with either modules
+compiled with @samp{-mrelocatable-lib} can be linked with either modules
compiled without @samp{-mrelocatable} and @samp{-mrelocatable-lib} or
with modules compiled with the @samp{-mrelocatable} options.
Linux-based GNU system.
@item -mprototype
-@item -mno-prototype
+@itemx -mno-prototype
On System V.4 and embedded PowerPC systems assume that all calls to
variable argument functions are properly prototyped. Otherwise, the
compiler must insert an instruction before every non prototyped call to
@item -mmvme
On embedded PowerPC systems, assume that the startup module is called
-@file{mvme-crt0.o} and the standard C libraries are @file{libmvme.a} and
+@file{crt0.o} and the standard C libraries are @file{libmvme.a} and
+@file{libc.a}.
+
+@item -mads
+On embedded PowerPC systems, assume that the startup module is called
+@file{crt0.o} and the standard C libraries are @file{libads.a} and
+@file{libc.a}.
+
+@item -myellowknife
+On embedded PowerPC systems, assume that the startup module is called
+@file{crt0.o} and the standard C libraries are @file{libyk.a} and
@file{libc.a}.
@item -memb
@item -G @var{num}
@cindex smaller data references (PowerPC)
@cindex .sdata/.sdata2 references (PowerPC)
-On embbeded PowerPC systems, put global and static items less than or
+On embedded PowerPC systems, put global and static items less than or
equal to @var{num} bytes into the small data or bss sections instead of
the normal data or bss section. By default, @var{num} is 8. The
@samp{-G @var{num}} switch is also passed to the linker.
These @samp{-m} options are defined for the i386 family of computers:
@table @code
-@item -m486
-@itemx -m386
-Control whether or not code is optimized for a 486 instead of an
-386. Code generated for an 486 will run on a 386 and vice versa.
+@item -mcpu=@var{cpu type}
+Assume the defaults for the machine type @var{cpu type} when scheduling
+instructions. The choices for @var{cpu type} are: @samp{i386},
+@samp{i486}, @samp{i586} (@samp{pentium}), @samp{pentium}, @samp{i686}
+(@samp{pentiumpro}) and @samp{pentiumpro}. While picking a specific
+@var{cpu type} will schedule things appropriately for that particular
+chip, the compiler will not generate any code that does not run on the
+i386 without the @samp{-march=@var{cpu type}} option being used.
+
+@item -march=@var{cpu type}
+Generate instructions for the machine type @var{cpu type}. The choices
+for @var{cpu type} are: @samp{i386}, @samp{i486}, @samp{pentium}, and
+@samp{pentiumpro}. Specifying @samp{-march=@var{cpu type}} implies
+@samp{-mcpu=@var{cpu type}}.
+
+@item -m386
+@itemx -m486
+@itemx -mpentium
+@itemx -mpentiumpro
+Synonyms for -mcpu=i386, -mcpu=i486, -mcpu=pentium, and -mcpu=pentiumpro
+respectively.
@item -mieee-fp
@itemx -mno-ieee-fp
@item -malign-functions=@var{num}
Align the start of functions to a 2 raised to @var{num} byte boundary.
-If @samp{-malign-jumps} is not specified, the default is 2 if optimizing
+If @samp{-malign-functions} is not specified, the default is 2 if optimizing
for a 386, and 4 if optimizing for a 486.
@end table
@item -mspace
Optimize for space rather than execution time. Currently this only
enables out of line function prologues and epilogues. This option is
-incompatable with PIC code generation and profiling.
+incompatible with PIC code generation and profiling.
@item -mlong-load-store
Generate 3-instruction load and store sequences as sometimes required by
Normally GNU CC examines a 32- or 64-bit integer constant to
see if it can construct it from smaller constants in two or three
instructions. If it cannot, it will output the constant as a literal and
-generate code to load it from the data segement at runtime.
+generate code to load it from the data segment at runtime.
Use this option to require GNU CC to construct @emph{all} integer constants
using code, even if it takes more instructions (the maximum is six).
You would typically use this option to build a shared library dynamic
loader. Itself a shared library, it must relocate itself in memory
before it can find the variables and constants in its own data segment.
+
+@item -malpha-as
+@itemx -mgas
+Select whether to generate code to be assembled by the vendor-supplied
+assembler (@samp{-malpha-as}) or by the GNU assembler @samp{-mgas}.
+
+@item -mbwx
+@itemx -mno-bwx
+@itemx -mcix
+@itemx -mno-cix
+@itemx -mmax
+@itemx -mno-max
+Indicate whether GNU CC should generate code to use the optional BWX,
+CIX, and MAX instruction sets. The default is to use the instruction sets
+supported by the CPU type specified via @samp{-mcpu=} option or that
+of the CPU on which GNU CC was built if none was specified.
+
+@item -mcpu=@var{cpu type}
+@item -mcpu=@var{cpu_type}
+Set the instruction set, register set, and instruction scheduling
+parameters for machine type @var{cpu_type}. You can specify either the
+@samp{EV} style name or the corresponding chip number. GNU CC
+supports scheduling parameters for the EV4 and EV5 family of processors
+and will choose the default values for the instruction set from
+the processor you specify. If you do not specify a processor type,
+GNU CC will default to the processor on which the compiler was built.
+
+Supported values for @var{cpu_type} are
+
+@table @samp
+@item ev4
+@itemx 21064
+Schedules as an EV4 and has no instruction set extensions.
+
+@item ev5
+@itemx 21164
+Schedules as an EV5 and has no instruction set extensions.
+
+@item ev56
+@itemx 21164a
+Schedules as an EV5 and supports the BWX extension.
+
+@item pca56
+@itemx 21164PC
+Schedules as an EV5 and supports the BWX and MAX extensions.
+
+@item ev6
+@itemx 21264
+Schedules as an EV5 (until Digital releases the scheduling parameters
+for the EV6) and supports the BWX, CIX, and MAX extensions.
+@end table
@end table
@node Clipper Options
@item -mh
Generate code for the H8/300H.
+@item -ms
+Generate code for the H8/S.
+
@item -mint32
Make @code{int} data 32 bits by default.
@c the generic assembler that comes with Solaris takes just -Ym.
@end table
+@node V850 Options
+@subsection V850 Options
+@cindex V850 Options
+
+These @samp{-m} options are defined for V850 implementations:
+
+@table @code
+@item -mlong-calls
+@itemx -mno-long-calls
+Treat all calls as being far away (near). If calls are assumed to be
+far away, the compiler will always load the functions address up into a
+register, and call indirect through the pointer.
+
+@item -mno-ep
+@item -mep
+Do not optimize (do optimize) basic blocks that use the same index
+pointer 4 or more times to copy pointer into the @code{ep} register, and
+use the shorter @code{sld} and @code{sst} instructions. The @samp{-mep}
+option is on by default if you optimize.
+
+@item -mno-prolog-function
+@itemx -mprolog-function
+Do not use (do use) external functions to save and restore registers at
+the prolog and epilog of a function. The external functions are slower,
+but use less code space if more than one function saves the same number
+of registers. The @samp{-mprolog-function} option is on by default if
+you optimize.
+
+@item -mspace
+Try to make the code as small as possible. At present, this just turns
+on the @samp{-mep} and @samp{-mprolog-function} options.
+
+@item -mtda=@var{n}
+Put static or global variables whose size is @var{n} bytes or less into
+the tiny data area that register @code{ep} points to. The tiny data
+area can hold up to 256 bytes in total (128 bytes for byte references).
+
+@item -msda=@var{n}
+Put static or global variables whose size is @var{n} bytes or less into
+the small data area that register @code{gp} points to. The small data
+area can hold up to 64 kilobytes.
+
+@item -mzda=@var{n}
+Put static or global variables whose size is @var{n} bytes or less into
+the first 32 kilobytes of memory.
+
+@item -mv850
+Specify that the target processor is the V850.
+
+@item -mbig-switch
+Generate code suitable for big switch tables. Use this option only if
+the assembler/linker complain about out of range branches within a switch
+table.
+@end table
+
@node Code Gen Options
@section Options for Code Generation Conventions
@cindex code generation conventions
it.
@table @code
+@item -fexceptions
+Enable exception handling, and generate extra code needed to propagate
+exceptions. If you do not specify this option, GNU CC enables it by
+default for languages like C++ that normally require exception handling,
+and disabled for languages like C that do not normally require it.
+However, when compiling C code that needs to interoperate properly with
+exception handlers written in C++, you may need to enable this option.
+You may also wish to disable this option is you are compiling older C++
+programs that don't use exception handling.
+
@item -fpcc-struct-return
Return ``short'' @code{struct} and @code{union} values in memory like
longer ones, rather than in registers. This convention is less
three-way choice.
@item -fcall-used-@var{reg}
-Treat the register named @var{reg} as an allocatable register that is
+Treat the register named @var{reg} as an allocable register that is
clobbered by function calls. It may be allocated for temporaries or
variables that do not live across a call. Functions compiled this way
will not save and restore the register @var{reg}.
three-way choice.
@item -fcall-saved-@var{reg}
-Treat the register named @var{reg} as an allocatable register saved by
+Treat the register named @var{reg} as an allocable register saved by
functions. It may be allocated even for temporaries or variables that
live across a call. Functions compiled this way will save and restore
the register @var{reg} if they use it.
@code{asm} or @code{__asm__} keywords.
You must also specify this option when you compile functions you call that
-have side effects. If you do not, you may get erronous messages from
+have side effects. If you do not, you may get erroneous messages from
the detector. Normally, you should compile all your code with this option.
If you use functions from a library that have side-effects (such as
@code{read}), you may not be able to recompile the library and
a single-threaded environment since stack overflow is automatically
detected on nearly all systems if there is only one stack.
+@item -fexceptions
+Enable exception handling. For some targets, this implies
+generation of frame unwind information for all functions, which can produce
+significant data size overhead, though it does not affect execution.
+
+This option is on by default for languages that support exception
+handling (such as C++), and off for those that don't (such as C).
+
@item +e0
@itemx +e1
Control whether virtual function definitions in classes are used to
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