-@c Copyright (C) 1988,89,92,93,94,95,96,97,98,1999 Free Software Foundation, Inc.
+@c Copyright (C) 1988, 89, 92-98, 1999 Free Software Foundation, Inc.
@c This is part of the GCC manual.
@c For copying conditions, see the file gcc.texi.
-fno-implement-inlines -fname-mangling-version-@var{n} -fno-default-inline
-foperator-names -fno-optional-diags -frepo -fstrict-prototype
-fsquangle -ftemplate-depth-@var{n} -fthis-is-variable -fvtable-thunks
--nostdinc++
+-nostdinc++ -Wctor-dtor-privacy -Weffc++ -Wno-non-template-friend
+-Wnon-virtual-dtor -Wold-style-cast -Woverloaded-virtual
+-Wno-pmf-conversions -Wreorder -Wsign-promo -Wsynth
@end smallexample
@item Warning Options
-Wlarger-than-@var{len} -Wlong-long
-Wmain -Wmissing-declarations -Wmissing-noreturn
-Wmissing-prototypes -Wmultichar -Wnested-externs -Wno-import
--Wno-non-template-friend -Wold-style-cast -Woverloaded-virtual
--Wparentheses -Wpointer-arith -Wredundant-decls -Wreorder
+-Wparentheses -Wpointer-arith -Wredundant-decls
-Wreturn-type -Wshadow -Wsign-compare -Wstrict-prototypes
--Wswitch -Wsynth -Wtraditional
+-Wswitch -Wtraditional
-Wtrigraphs -Wundef -Wuninitialized -Wunused -Wwrite-strings
-Wunknown-pragmas
@end smallexample
-idirafter @var{dir}
-include @var{file} -imacros @var{file}
-iprefix @var{file} -iwithprefix @var{dir}
--iwithprefixbefore @var{dir} -isystem @var{dir}
+-iwithprefixbefore @var{dir} -isystem @var{dir} -isystem-c++ @var{dir}
-M -MD -MM -MMD -MG -nostdinc -P -trigraphs
-undef -U@var{macro} -Wp,@var{option}
@end smallexample
-mcpu= -march= -mfpe=
-mstructure-size-boundary=
-mbsd -mxopen -mno-symrename
+-mabort-on-noreturn
+-mno-sched-prolog
@emph{Thumb Options}
-mtpcs-frame -mno-tpcs-frame
-mabicalls -mcpu=@var{cpu type} -membedded-data
-membedded-pic -mfp32 -mfp64 -mgas -mgp32 -mgp64
-mgpopt -mhalf-pic -mhard-float -mint64 -mips1
--mips2 -mips3 -mips4 -mlong64 -mlong-calls -mmemcpy
+-mips2 -mips3 -mips4 -mlong64 -mlong32 -mlong-calls -mmemcpy
-mmips-as -mmips-tfile -mno-abicalls
-mno-embedded-data -mno-embedded-pic
-mno-gpopt -mno-long-calls
-fno-common -fno-ident -fno-gnu-linker
-fpcc-struct-return -fpic -fPIC
-freg-struct-return -fshared-data -fshort-enums
--fshort-double -fvolatile -fvolatile-global
+-fshort-double -fvolatile -fvolatile-global -fvolatile-static
-fverbose-asm -fpack-struct -fstack-check
-fargument-alias -fargument-noalias
-fargument-noalias-global
@cindex suffixes for C++ source
@cindex C++ source file suffixes
C++ source files conventionally use one of the suffixes @samp{.C},
-@samp{.cc}, @samp{cpp}, or @samp{.cxx}; preprocessed C++ files use the
-suffix @samp{.ii}. GNU CC recognizes files with these names and
-compiles them as C++ programs even if you call the compiler the same way
-as for compiling C programs (usually with the name @code{gcc}).
+@samp{.cc}, @samp{.cpp}, @samp{.c++}, @samp{.cp}, or @samp{.cxx};
+preprocessed C++ files use the suffix @samp{.ii}. GNU CC recognizes
+files with these names and compiles them as C++ programs even if you
+call the compiler the same way as for compiling C programs (usually with
+the name @code{gcc}).
@findex g++
@findex c++
or otherwise without a suffix that flags them as C++ programs.
@code{g++} is a program that calls GNU CC with the default language
set to C++, and automatically specifies linking against the C++
-library.
-@cindex @code{g++ 1.@var{xx}}
-@cindex @code{g++}, separate compiler
-@cindex @code{g++} older version
-@footnote{Prior to release 2 of the compiler,
-there was a separate @code{g++} compiler. That version was based on GNU
-CC, but not integrated with it. Versions of @code{g++} with a
-@samp{1.@var{xx}} version number---for example, @code{g++} version 1.37
-or 1.42---are much less reliable than the versions integrated with GCC
-2. Moreover, combining G++ @samp{1.@var{xx}} with a version 2 GCC will
-simply not work.} On many systems, the script @code{g++} is also
+library. On many systems, the script @code{g++} is also
installed with the name @code{c++}.
@cindex invoking @code{g++}
@findex strcmp
@findex strcpy
@findex strlen
-Don't recognize builtin functions that do not begin with `__builtin_'
+Don't recognize builtin functions that do not begin with @samp{__builtin_}
as prefix. Currently, the functions affected include @code{abort},
@code{abs}, @code{alloca}, @code{cos}, @code{exit}, @code{fabs},
@code{ffs}, @code{labs}, @code{memcmp}, @code{memcpy}, @code{sin},
libgcc} must be built with the same setting of this option.
@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
-Instantiation}, for more information.
+Never emit code for non-inline templates which are instantiated
+implicitly (i.e. by use); only emit code for explicit instantiations.
+@xref{Template Instantiation}, for more information.
+
+@item -fno-implicit-inline-templates
+Don't emit code for implicit instantiations of inline templates, either.
+The default is to handle inlines differently so that compiles with and
+without optimization will need the same set of explicit instantiations.
@item -finit-priority
Support @samp{__attribute__ ((init_priority (n)))} for controlling the
template <class T, class U> void foo(T t);
@end example
+Like all options that change the ABI, all C++ code, @emph{including
+libgcc} must be built with the same setting of this option.
+
@item -foperator-names
Recognize the operator name keywords @code{and}, @code{bitand},
@code{bitor}, @code{compl}, @code{not}, @code{or} and @code{xor} as
@item -fno-optional-diags
Disable diagnostics that the standard says a compiler does not need to
-issue. Currently, this means the diagnostic for a name having multiple
-meanings within a class.
+issue. Currently, the only such diagnostic issued by g++ is the one for
+a name having multiple meanings within a class.
+
+@item -fpermissive
+Downgrade messages about nonconformant code from errors to warnings. By
+default, g++ effectively sets @samp{-pedantic-errors} without
+@samp{-pedantic}; this option reverses that. This behavior and this
+option are superceded by @samp{-pedantic}, which works as it does for GNU C.
@item -frepo
Enable automatic template instantiation. This option also implies
@samp{-fno-implicit-templates}. @xref{Template Instantiation}, for more
information.
+@item -fno-rtti
+Disable generation of the information used by C++ runtime type
+identification features (@samp{dynamic_cast} and @samp{typeid}). If you
+don't use those parts of the language (or exception handling, which uses
+@samp{dynamic_cast} internally), you can save some space by using this
+flag.
+
@item -fstrict-prototype
Within an @samp{extern "C"} linkage specification, treat a function
declaration with no arguments, such as @samp{int foo ();}, as declaring
implementations store a single pointer to a @samp{thunk} function which
does any necessary adjustment and then calls the target function.
+This option also enables a heuristic for controlling emission of
+vtables; if a class has any non-inline virtual functions, the vtable
+will be emitted in the translation unit containing the first one of
+those.
+
Like all options that change the ABI, all C++ code, @emph{including
libgcc.a} must be built with the same setting of this option.
functions will have linkage like inline functions; they just won't be
inlined by default.
-@item -Wno-non-template-friend
-@xref{Warning Options,,Options to Request or Suppress Warnings}.
-@item -Wold-style-cast
-@itemx -Woverloaded-virtual
-Warnings that apply only to C++ programs. @xref{Warning
-Options,,Options to Request or Suppress Warnings}.
+@item -Wctor-dtor-privacy (C++ only)
+Warn when a class seems unusable, because all the constructors or
+destructors in a class are private and the class has no friends or
+public static member functions.
+
+@item -Wnon-virtual-dtor (C++ only)
+Warn when a class declares a non-virtual destructor that should probably
+be virtual, because it looks like the class will be used polymorphically.
+
+@item -Wreorder (C++ only)
+@cindex reordering, warning
+@cindex warning for reordering of member initializers
+Warn when the order of member initializers given in the code does not
+match the order in which they must be executed. For instance:
+
+@smallexample
+struct A @{
+ int i;
+ int j;
+ A(): j (0), i (1) @{ @}
+@};
+@end smallexample
+
+Here the compiler will warn that the member initializers for @samp{i}
+and @samp{j} will be rearranged to match the declaration order of the
+members.
+@end table
+
+The following @samp{-W@dots{}} options are not affected by @samp{-Wall}.
+
+@table @code
+@item -Weffc++ (C++ only)
+Warn about violations of various style guidelines from Scott Meyers'
+@cite{Effective C++} books. If you use this option, you should be aware
+that the standard library headers do not obey all of these guidelines;
+you can use @samp{grep -v} to filter out those warnings.
+
+@item -Wno-non-template-friend (C++ only)
+Disable warnings when non-templatized friend functions are declared
+within a template. With the advent of explicit template specification
+support in g++, if the name of the friend is an unqualified-id (ie,
+@samp{friend foo(int)}), the C++ language specification demands that the
+friend declare or define an ordinary, nontemplate function. (Section
+14.5.3). Before g++ implemented explicit specification, unqualified-ids
+could be interpreted as a particular specialization of a templatized
+function. Because this non-conforming behavior is no longer the default
+behavior for g++, @samp{-Wnon-template-friend} allows the compiler to
+check existing code for potential trouble spots, and is on by default.
+This new compiler behavior can also be turned off with the flag
+@samp{-fguiding-decls}, which activates the older, non-specification
+compiler code, or with @samp{-Wno-non-template-friend} which keeps the
+conformant compiler code but disables the helpful warning.
+
+@item -Wold-style-cast (C++ only)
+Warn if an old-style (C-style) cast 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.
+
+@item -Woverloaded-virtual (C++ only)
+@cindex overloaded virtual fn, warning
+@cindex warning for overloaded virtual fn
+Warn when a derived class function declaration may be an error in
+defining a virtual function. In a derived class, the
+definitions of virtual functions must match the type signature of a
+virtual function declared in the base class. With this option, the
+compiler warns when you define a function with the same name as a
+virtual function, but with a type signature that does not match any
+declarations from the base class.
+
+@item -Wno-pmf-conversions (C++ only)
+Disable the diagnostic for converting a bound pointer to member function
+to a plain pointer.
+
+@item -Wsign-promo (C++ only)
+Warn when overload resolution chooses a promotion from unsigned or
+enumeral type to a signed type over a conversion to an unsigned type of
+the same size. Previous versions of g++ would try to preserve
+unsignedness, but the standard mandates the current behavior.
+
+@item -Wsynth (C++ only)
+@cindex warning for synthesized methods
+@cindex synthesized methods, warning
+Warn when g++'s synthesis behavior does not match that of cfront. For
+instance:
-@item -Weffc++
-Warn about violation of some style rules from Effective C++ by Scott Myers.
+@smallexample
+struct A @{
+ operator int ();
+ A& operator = (int);
+@};
+
+main ()
+@{
+ A a,b;
+ a = b;
+@}
+@end smallexample
+
+In this example, g++ will synthesize a default @samp{A& operator =
+(const A&);}, while cfront will use the user-defined @samp{operator =}.
@end table
@node Warning Options
you use that never return as @code{noreturn}. @xref{Function
Attributes}.
-@item -Wreorder (C++ only)
-@cindex reordering, warning
-@cindex warning for reordering of member initializers
-Warn when the order of member initializers given in the code does not
-match the order in which they must be executed. For instance:
-
-@smallexample
-struct A @{
- int i;
- int j;
- A(): j (0), i (1) @{ @}
-@};
-@end smallexample
-
-Here the compiler will warn that the member initializers for @samp{i}
-and @samp{j} will be rearranged to match the declaration order of the
-members.
-
-@item -Wtemplate-debugging
-@cindex template debugging
-When using templates in a C++ program, warn if debugging is not yet
-fully available (C++ only).
-
@item -Wunknown-pragmas
@cindex warning for unknown pragmas
@cindex unknown pragmas, warning
@item
A @code{switch} statement has an operand of type @code{long}.
+
+@item
+A non-@code{static} function declaration follows a @code{static} one.
+This construct is not accepted by some traditional C compilers.
@end itemize
@item -Wundef
@item -Wnested-externs
Warn if an @code{extern} declaration is encountered within an function.
-@item -Wno-non-template-friend
-Disable warnings when non-templatized friend functions are declared
-within a template. With the advent of explicit template specification
-support in g++, if the name of the friend is an unqualified-id (ie,
-@samp{friend foo(int)}), the C++ language specification demands that the
-friend declare or define an ordinary, nontemplate function. (Section
-14.5.3). Before g++ implemented explicit specification, unqualified-ids
-could be interpreted as a particular specialization of a templatized
-function. Because this non-conforming behavior is no longer the default
-behavior for g++, @samp{-Wnon-template-friend} allows the compiler to
-check existing code for potential trouble spots, and is on by default.
-This new compiler behavior can also be turned off with the flag
-@samp{-fguiding-decls}, which activates the older, non-specification
-compiler code, or with @samp{-Wno-non-template-friend} which keeps the
-conformant compiler code but disables the helpful warning.
-
@item -Winline
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
-Warn when a derived class function declaration may be an error in
-defining a virtual function (C++ only). In a derived class, the
-definitions of virtual functions must match the type signature of a
-virtual function declared in the base class. With this option, the
-compiler warns when you define a function with the same name as a
-virtual function, but with a type signature that does not match any
-declarations from the base class.
-
-@item -Wsynth (C++ only)
-@cindex warning for synthesized methods
-@cindex synthesized methods, warning
-Warn when g++'s synthesis behavior does not match that of cfront. For
-instance:
-
-@smallexample
-struct A @{
- operator int ();
- A& operator = (int);
-@};
-
-main ()
-@{
- A a,b;
- a = b;
-@}
-@end smallexample
-
-In this example, g++ will synthesize a default @samp{A& operator =
-(const A&);}, while cfront will use the user-defined @samp{operator =}.
-
@item -Wlong-long
Warn if @samp{long long} type is used. This is default. To inhibit
the warning messages, use @samp{-Wno-long-long}. Flags
Perform a number of minor optimizations that are relatively expensive.
@item -foptimize-register-moves
-@item -fregmove
+@itemx -fregmove
Attempt to reassign register numbers in move instructions and as
operands of other simple instructions in order to maximize the amount of
register tying. This is especially helpful on machines with two-operand
registers and where memory load instructions take more than one cycle.
@item -ffunction-sections
-@item -fdata-sections
+@itemx -fdata-sections
Place each function or data item into its own section in the output
file if the target supports arbitrary sections. The name of the
function or the name of the data item determines the section's name
they have helped determine the efficacy of various
approaches to improving loop optimizations.
-Please let us (@code{egcs@@cygnus.com} and @code{fortran@@gnu.org})
+Please let us (@code{egcs@@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}
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}.
+@samp{hypersparc}, @samp{sparclite86x}, @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},
@smallexample
v7: cypress
- v8: supersparc
- sparclite: f930, f934
+ v8: supersparc, hypersparc
+ sparclite: f930, f934, sparclite86x
sparclet: tsc701
v9: ultrasparc
@end smallexample
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}.
+@samp{hypersparc}, @samp{f930}, @samp{f934}, @samp{sparclite86x},
+@samp{tsc701}, @samp{ultrasparc}.
@item -malign-loops=@var{num}
Align loops to a 2 raised to a @var{num} byte boundary. If
this can't be done directly in cross-compilation. You must make your
own arrangements to provide suitable library functions for
cross-compilation.
+
+@item -mno-multm
+@kindex -mno-multm
+Do not generate multm or multmu instructions. This is useful for some embedded
+systems which do not have trap handlers for these instructions.
@end table
@node ARM Options
compiler is built for cross-compilation.
@item -mcpu=<name>
+@itemx -mtune=<name>
@kindex -mcpu=
+@kindex -mtune=
This specifies the name of the target ARM processor. GCC uses this name
to determine what kind of instructions it can use when generating
assembly code. Permissable names are: arm2, arm250, arm3, arm6, arm60,
arm600, arm610, arm620, arm7, arm7m, arm7d, arm7dm, arm7di, arm7dmi,
arm70, arm700, arm700i, arm710, arm710c, arm7100, arm7500, arm7500fe,
-arm7tdmi, arm8, strongarm, strongarm110
+arm7tdmi, arm8, strongarm, strongarm110, strongarm1100, arm8, arm810,
+arm9, arm9tdmi. @samp{-mtune=} is a synonym for @samp{-mcpue=} to
+support older versions of GCC.
@item -march=<name>
@kindex -march=
armv3, armv3m, armv4, armv4t
@item -mfpe=<number>
+@itemx -mfp=<number>
@kindex -mfpe=
+@kindex -mfp=
This specifes the version of the floating point emulation available on
-the target. Permissable values are 2 and 3.
+the target. Permissable values are 2 and 3. @samp{-mfp=} is a synonym
+for @samp{-mfpe=} to support older versions of GCC.
@item -mstructure-size-boundary=<n>
@kindex -mstructure-size-boundary
using structures or unions. Programmers are encouraged to use the 32
value as future versions of the toolchain may default to this value.
+@item -mabort-on-noreturn
+@kindex -mabort-on-noreturn
+@kindex -mnoabort-on-noreturn
+Generate a call to the function abort at the end of a noreturn function.
+It will be executed if the function tries to return.
+
@end table
@node Thumb Options
instruction scheduling parameters for machine type @var{cpu_type}.
Supported values for @var{cpu_type} are @samp{rs6000}, @samp{rios1},
@samp{rios2}, @samp{rsc}, @samp{601}, @samp{602}, @samp{603},
-@samp{603e}, @samp{604}, @samp{604e}, @samp{620}, @samp{power},
-@samp{power2}, @samp{powerpc}, @samp{403}, @samp{505}, @samp{801},
-@samp{821}, @samp{823}, and @samp{860} and @samp{common}.
-@samp{-mcpu=power}, @samp{-mcpu=power2}, and @samp{-mcpu=powerpc}
-specify generic POWER, POWER2 and pure PowerPC (i.e., not MPC601)
-architecture machine types, with an appropriate, generic processor model
-assumed for scheduling purposes.@refill
+@samp{603e}, @samp{604}, @samp{604e}, @samp{620}, @samp{740},
+@samp{750}, @samp{power}, @samp{power2}, @samp{powerpc}, @samp{403},
+@samp{505}, @samp{801}, @samp{821}, @samp{823}, and @samp{860} and
+@samp{common}. @samp{-mcpu=power}, @samp{-mcpu=power2}, and
+@samp{-mcpu=powerpc} specify generic POWER, POWER2 and pure PowerPC
+(i.e., not MPC601) architecture machine types, with an appropriate,
+generic processor model assumed for scheduling purposes.@refill
@c overfull hbox here --bob 22 jul96
@c original text between ignore ... end ignore
instructions are generated by default on POWER systems, and not
generated on PowerPC systems. Do not use @samp{-mmultiple} on little
endian PowerPC systems, since those instructions do not work when the
-processor is in little endian mode.
+processor is in little endian mode. The exceptions are PPC740 and
+PPC750 which permit the instructions usage in little endian mode.
@item -mstring
@itemx -mno-string
@kindex -mstring
-Generate code that uses (does not use) the load string instructions and the
-store string word instructions to save multiple registers and do small block
-moves. These instructions are generated by default on POWER systems, and not
-generated on PowerPC systems. Do not use @samp{-mstring} on little endian
-PowerPC systems, since those instructions do not work when the processor is in
-little endian mode.
+Generate code that uses (does not use) the load string instructions
+and the store string word instructions to save multiple registers and
+do small block moves. These instructions are generated by default on
+POWER systems, and not generated on PowerPC systems. Do not use
+@samp{-mstring} on little endian PowerPC systems, since those
+instructions do not work when the processor is in little endian mode.
+The exceptions are PPC740 and PPC750 which permit the instructions
+usage in little endian mode.
@item -mupdate
@itemx -mno-update
@itemx -mno-regnames
On System V.4 and embedded PowerPC systems do (do not) emit register
names in the assembly language output using symbolic forms.
+
@end table
+
@node RT Options
@subsection IBM RT Options
@cindex RT options
@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{r2000}, @samp{r3000},
-@samp{r4000}, @samp{r4400}, @samp{r4600}, and @samp{r6000}. 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
-meet level 1 of the MIPS ISA (instruction set architecture) without
-the @samp{-mips2} or @samp{-mips3} switches being used.
+@samp{r3900}, @samp{r4000}, @samp{r4100}, @samp{r4300}, @samp{r4400},
+@samp{r4600}, @samp{r4650}, @samp{r5000}, @samp{r6000}, @samp{r8000},
+and @samp{orion}. Additionally, the @samp{r2000}, @samp{r3000},
+@samp{r4000}, @samp{r5000}, and @samp{r6000} can be abbreviated as
+@samp{r2k} (or @samp{r2K}), @samp{r3k}, etc. 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 meet level 1
+of the MIPS ISA (instruction set architecture) without a @samp{-mipsX}
+or @samp{-mabi} switch being used.
@item -mips1
Issue instructions from level 1 of the MIPS ISA. This is the default.
@item -mips3
Issue instructions from level 3 of the MIPS ISA (64 bit instructions).
@samp{r4000} is the default @var{cpu type} at this ISA level.
-This option does not change the sizes of any of the C data types.
@item -mips4
-Issue instructions from level 4 of the MIPS ISA. @samp{r8000} is the
-default @var{cpu type} at this ISA level.
+Issue instructions from level 4 of the MIPS ISA (conditional move,
+prefetch, enhanced FPU instructions). @samp{r8000} is the default
+@var{cpu type} at this ISA level.
@item -mfp32
Assume that 32 32-bit floating point registers are available. This is
the default when the @samp{-mips3} option is used.
@item -mint64
-Types long, int, and pointer are 64 bits. This works only if @samp{-mips3}
-is also specified.
+Force int and long types to be 64 bits wide. See @samp{-mlong32} for an
+explanation of the default, and the width of pointers.
@item -mlong64
-Types long and pointer are 64 bits, and type int is 32 bits.
-This works only if @samp{-mips3} is also specified.
+Force long types to be 64 bits wide. See @samp{-mlong32} for an
+explanation of the default, and the width of pointers.
+
+@item -mlong32
+Force long, int, and pointer types to be 32 bits wide.
+
+If none of @samp{-mlong32}, @samp{-mlong64}, or @samp{-mint64} are set,
+the size of ints, longs, and pointers depends on the ABI and ISA choosen.
+For @samp{-mabi=32}, and @samp{-mabi=n32}, ints and longs are 32 bits
+wide. For @samp{-mabi=64}, ints are 32 bits, and longs are 64 bits wide.
+For @samp{-mabi=eabi} and either @samp{-mips1} or @samp{-mips2}, ints
+and longs are 32 bits wide. For @samp{-mabi=eabi} and higher ISAs, ints
+are 32 bits, and longs are 64 bits wide. The width of pointer types is
+the smaller of the width of longs or the width of general purpose
+registers (which in turn depends on the ISA).
@itemx -mabi=32
+@itemx -mabi=o64
@itemx -mabi=n32
@itemx -mabi=64
@itemx -mabi=eabi
-Generate code for the indicated ABI.
+Generate code for the indicated ABI. The default instruction level is
+@samp{-mips1} for @samp{32}, @samp{-mips3} for @samp{n32}, and
+@samp{-mips4} otherwise. Conversely, with @samp{-mips1} or
+@samp{-mips2}, the default ABI is @samp{32}; otherwise, the default ABI
+is @samp{64}.
@item -mmips-as
Generate code for the MIPS assembler, and invoke @file{mips-tfile} to
Turns on @samp{-msingle-float}, @samp{-mmad}, and, at least for now,
@samp{-mcpu=r4650}.
+@item -mips16
+@itemx -mno-mips16
+Enable 16-bit instructions.
+
+@item -mentry
+Use the entry and exit pseudo ops. This option can only be used with
+@samp{-mips16}.
+
@item -EL
Compile code for the processor in little endian mode.
The requisite libraries are assumed to exist.
You can specify that an individual function is called with this calling
sequence with the function attribute @samp{stdcall}. You can also
override the @samp{-mrtd} option by using the function attribute
-@samp{cdecl}. @xref{Function Attributes}
+@samp{cdecl}. @xref{Function Attributes}.
@strong{Warning:} this calling convention is incompatible with the one
normally used on Unix, so you cannot use it if you need to call
Control how many registers are used to pass integer arguments. By
default, no registers are used to pass arguments, and at most 3
registers can be used. You can control this behavior for a specific
-function by using the function attribute @samp{regparm}. @xref{Function Attributes}
+function by using the function attribute @samp{regparm}.
+@xref{Function Attributes}.
@strong{Warning:} if you use this switch, and
@var{num} is nonzero, then you must build all modules with the same
@item -mschedule=@var{cpu type}
Schedule code according to the constraints for the machine type
-@var{cpu type}. The choices for @var{cpu type} are @samp{700} for
-7@var{n}0 machines, @samp{7100} for 7@var{n}5 machines, and @samp{7100LC}
-for 7@var{n}2 machines. @samp{7100} is the default for @var{cpu type}.
-
-Note the @samp{7100LC} scheduling information is incomplete and using
-@samp{7100LC} often leads to bad schedules. For now it's probably best
-to use @samp{7100} instead of @samp{7100LC} for the 7@var{n}2 machines.
+@var{cpu type}. The choices for @var{cpu type} are @samp{700}
+@samp{7100}, @samp{7100LC}, @samp{7200}, and @samp{8000}. Refer to
+@file{/usr/lib/sched.models} on an HP-UX system to determine the
+proper scheduling option for your machine.
@item -mlinker-opt
Enable the optimization pass in the HPUX linker. Note this makes symbolic
@item -mold-align
Enable structure-alignment compatibility with Intel's gcc release version
1.3 (based on gcc 1.37). This option implies @samp{-mstrict-align}.
+
+@item -mlong-double-64
+Implement type @samp{long double} as 64-bit floating point numbers.
+Without the option @samp{long double} is implemented by 80-bit
+floating point numbers. The only reason we have it because there is
+no 128-bit @samp{long double} support in @samp{fp-bit.c} yet. So it
+is only useful for people using soft-float targets. Otherwise, we
+should recommend against use of it.
+
@end table
@node DEC Alpha Options
All variants support @samp{-mcpu=base}, this is the default.
@item -mtext=@var{text section}
-@item -mdata=@var{data section}
-@item -mrodata=@var{readonly data section}
+@itemx -mdata=@var{data section}
+@itemx -mrodata=@var{readonly data section}
Put functions, data, and readonly data in @var{text section},
@var{data section}, and @var{readonly data section} respectively
by default. This can be overridden with the @code{section} attribute.
-@xref{Variable Attributes}
+@xref{Variable Attributes}.
@end table
@item -fvolatile-global
Consider all memory references to extern and global data items to
-be volatile.
+be volatile. GNU CC does not consider static data items to be volatile
+because of this switch.
+
+@item -fvolatile-static
+Consider all memory references to static data to be volatile.
@item -fpic
@cindex global offset table
code that is suitable for a detector of bad memory accesses such as
@file{Checker}.
-You must also specify this option when you compile functions you call that
-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.
+Normally, you should compile all, or none, of your code with this option.
+
+If you do mix code compiled with and without this option,
+you must ensure that all code that has side effects
+and that is called by code compiled with this option
+is, itself, compiled with this option.
+If you do not, you might get erroneous messages from the detector.
+
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
+@code{read}), you might not be able to recompile the library and
specify this option. In that case, you can enable the
@samp{-fprefix-function-name} option, which requests GNU CC to encapsulate
your code and make other functions look as if they were compiled with
@samp{-fcheck-memory-usage}. This is done by calling ``stubs'',
which are provided by the detector. If you cannot find or build
-stubs for every function you call, you may have to specify
+stubs for every function you call, you might have to specify
@samp{-fcheck-memory-usage} without @samp{-fprefix-function-name}.
If you specify this option, you can not use the @code{asm} or
Request GNU CC to add a prefix to the symbols generated for function names.
GNU CC adds a prefix to the names of functions defined as well as
functions called. Code compiled with this option and code compiled
-without the option can't be linked together, unless or stubs are used.
+without the option can't be linked together, unless stubs are used.
If you compile the following code with @samp{-fprefix-function-name}
@example
foo (int a)
@{
return bar (a + 5);
-
@}
@end example
@end ifset
@table @code
+@item LANG
+@itemx LC_CTYPE
+@c @itemx LC_COLLATE
+@itemx LC_MESSAGES
+@c @itemx LC_MONETARY
+@c @itemx LC_NUMERIC
+@c @itemx LC_TIME
+@itemx LC_ALL
+@findex LANG
+@findex LC_CTYPE
+@c @findex LC_COLLATE
+@findex LC_MESSAGES
+@c @findex LC_MONETARY
+@c @findex LC_NUMERIC
+@c @findex LC_TIME
+@findex LC_ALL
+@cindex locale
+These environment variables control the way that GNU CC uses
+localization information that allow GNU CC to work with different
+national conventions. GNU CC inspects the locale categories
+@code{LC_CTYPE} and @code{LC_MESSAGES} if it has been configured to do
+so. These locale categories can be set to any value supported by your
+installation. A typical value is @samp{en_UK} for English in the United
+Kingdom.
+
+The @code{LC_CTYPE} environment variable specifies character
+classification. GNU CC uses it to determine the character boundaries in
+a string; this is needed for some multibyte encodings that contain quote
+and escape characters that would otherwise be interpreted as a string
+end or escape.
+
+The @code{LC_MESSAGES} environment variable specifies the language to
+use in diagnostic messages.
+
+If the @code{LC_ALL} environment variable is set, it overrides the value
+of @code{LC_CTYPE} and @code{LC_MESSAGES}; otherwise, @code{LC_CTYPE}
+and @code{LC_MESSAGES} default to the value of the @code{LANG}
+environment variable. If none of these variables are set, GNU CC
+defaults to traditional C English behavior.
+
@item TMPDIR
@findex TMPDIR
If @code{TMPDIR} is set, it specifies the directory to use for temporary
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