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invoke.texi: s/GNU CC/GCC/ for consistency with gcc.texi.

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* invoke.texi: s/GNU CC/GCC/ for consistency with gcc.texi.
        Fix documentation of -ansi flag to describe its C++ behavior.
        Remove bogus reference to GCC 2.9.

From-SVN: r28657
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Joe Buck 1999-08-11 00:37:09 -06:00 committed by Jeff Law
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commit 0c2d1a2a23
2 changed files with 143 additions and 131 deletions
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7
gcc/ChangeLog
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@ -1,3 +1,9 @@
Wed Aug 11 00:34:22 1999 Joe Buck <jbuck@synopsys.com>
* invoke.texi: s/GNU CC/GCC/ for consistency with gcc.texi.
Fix documentation of -ansi flag to describe its C++ behavior.
Remove bogus reference to GCC 2.9.
Tue Aug 10 17:19:02 1999 Jim Wilson <wilson@cygnus.com>
* config/sh/sh.c (machine_dependent_reorg): Only call PUT_MODE on
@ -417,6 +423,7 @@ Mon Aug 9 01:52:24 1999 Jason Merrill <jason@yorick.cygnus.com>
* except.c (expand_eh_region_start_for_decl): Always start a new block.
* stmt.c (is_eh_region): Make sure current_function is present, too.
>>>>>>> 1.4094
Mon Aug 9 01:15:24 1999 Jeffrey A Law (law@cygnus.com)
* pa.h (HARD_REGNO_MODE_OK): Correctly handle FPregs, even when

267
gcc/invoke.texi
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@ -3,12 +3,12 @@
@c For copying conditions, see the file gcc.texi.
@node Invoking GCC
@chapter GNU CC Command Options
@cindex GNU CC command options
@chapter GCC Command Options
@cindex GCC command options
@cindex command options
@cindex options, GNU CC command
@cindex options, GCC command
When you invoke GNU CC, it normally does preprocessing, compilation,
When you invoke GCC, it normally does preprocessing, compilation,
assembly and linking. The ``overall options'' allow you to stop this
process at an intermediate stage. For example, the @samp{-c} option
says not to run the linker. Then the output consists of object files
@ -20,7 +20,7 @@ options control the assembler and linker; most of these are not
documented here, since you rarely need to use any of them.
@cindex C compilation options
Most of the command line options that you can use with GNU CC are useful
Most of the command line options that you can use with GCC are useful
for C programs; when an option is only useful with another language
(usually C++), the explanation says so explicitly. If the description
for a particular option does not mention a source language, you can use
@ -69,12 +69,12 @@ only one of these two forms, whichever one is not the default.
* Directory Options:: Where to find header files and libraries.
Where to find the compiler executable files.
* Spec Files:: How to pass switches to sub-processes.
* Target Options:: Running a cross-compiler, or an old version of GNU CC.
* Target Options:: Running a cross-compiler, or an old version of GCC.
* Submodel Options:: Specifying minor hardware or convention variations,
such as 68010 vs 68020.
* Code Gen Options:: Specifying conventions for function calls, data layout
and register usage.
* Environment Variables:: Env vars that affect GNU CC.
* Environment Variables:: Env vars that affect GCC.
* Running Protoize:: Automatically adding or removing function prototypes.
@end menu
@ -452,7 +452,7 @@ in the following sections.
* Directory Options:: Where to find header files and libraries.
Where to find the compiler executable files.
* Spec Files:: How to pass switches to sub-processes.
* Target Options:: Running a cross-compiler, or an old version of GNU CC.
* Target Options:: Running a cross-compiler, or an old version of GCC.
@end menu
@node Overall Options
@ -602,7 +602,7 @@ be displayed.
@cindex C++ source file suffixes
C++ source files conventionally use one of the suffixes @samp{.C},
@samp{.cc}, @samp{.cpp}, @samp{.c++}, @samp{.cp}, or @samp{.cxx};
preprocessed C++ files use the suffix @samp{.ii}. GNU CC recognizes
preprocessed C++ files use the suffix @samp{.ii}. GCC 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}).
@ -613,7 +613,7 @@ However, C++ programs often require class libraries as well as a
compiler that understands the C++ language---and under some
circumstances, you might want to compile programs from standard input,
or otherwise without a suffix that flags them as C++ programs.
@code{g++} is a program that calls GNU CC with the default language
@code{g++} is a program that calls GCC with the default language
set to C++, and automatically specifies linking against the C++
library. On many systems, the script @code{g++} is also
installed with the name @code{c++}.
@ -640,14 +640,20 @@ from C, such as C++ and Objective C) that the compiler accepts:
@table @code
@cindex ANSI support
@item -ansi
Support all ANSI standard C programs.
In C mode, support all ANSI standard C programs. In C++ mode,
remove GNU extensions that conflict with ANSI C++.
@c shouldn't we be saying "ISO"?
This turns off certain features of GNU C that are incompatible with ANSI
C, such as the @code{asm}, @code{inline} and @code{typeof} keywords, and
This turns off certain features of GCC that are incompatible with ANSI
C (when compiling C code), or of ANSI standard C++ (when compiling C++ code),
such as the @code{asm} and @code{typeof} keywords, and
predefined macros such as @code{unix} and @code{vax} that identify the
type of system you are using. It also enables the undesirable and
rarely used ANSI trigraph feature, and it disables recognition of C++
style @samp{//} comments.
rarely used ANSI trigraph feature. For the C compiler,
it disables recognition of C++ style @samp{//} comments as well as
the @code{inline} keyword. For the C++ compiler,
@samp{-foperator-names} is enabled as well.
The alternate keywords @code{__asm__}, @code{__extension__},
@code{__inline__} and @code{__typeof__} continue to work despite
@ -945,7 +951,7 @@ g++ -g -frepo -O -c firstClass.C
@noindent
In this example, only @samp{-frepo} is an option meant
only for C++ programs; you can use the other options with any
language supported by GNU CC.
language supported by GCC.
Here is a list of options that are @emph{only} for compiling C++ programs:
@ -1321,8 +1327,7 @@ negative form beginning @samp{-Wno-} to turn off warnings;
for example, @samp{-Wno-implicit}. This manual lists only one of the
two forms, whichever is not the default.
These options control the amount and kinds of warnings produced by GNU
CC:
These options control the amount and kinds of warnings produced by GCC:
@table @code
@cindex syntax checking
@ -1346,7 +1351,7 @@ these escape routes; application programs should avoid them.
@xref{Alternate Keywords}.
This option is not intended to be @i{useful}; it exists only to satisfy
pedants who would otherwise claim that GNU CC fails to support the ANSI
pedants who would otherwise claim that GCC fails to support the ANSI
standard.
Some users try to use @samp{-pedantic} to check programs for strict ANSI
@ -1493,7 +1498,7 @@ to compute a value that itself is never used, because such
computations may be deleted by data flow analysis before the warnings
are printed.
These warnings are made optional because GNU CC is not smart
These warnings are made optional because GCC is not smart
enough to see all the reasons why the code might be correct
despite appearing to have an error. Here is one example of how
this can happen:
@ -1515,7 +1520,7 @@ this can happen:
@noindent
If the value of @code{y} is always 1, 2 or 3, then @code{x} is
always initialized, but GNU CC doesn't know this. Here is
always initialized, but GCC doesn't know this. Here is
another common case:
@smallexample
@ -1779,11 +1784,11 @@ Make all warnings into errors.
@end table
@node Debugging Options
@section Options for Debugging Your Program or GNU CC
@section Options for Debugging Your Program or GCC
@cindex options, debugging
@cindex debugging information options
GNU CC has various special options that are used for debugging
GCC has various special options that are used for debugging
either your program or GCC:
@table @code
@ -1801,7 +1806,7 @@ to generate the extra information, use @samp{-gstabs+}, @samp{-gstabs},
@samp{-gxcoff+}, @samp{-gxcoff}, @samp{-gdwarf-1+}, or @samp{-gdwarf-1}
(see below).
Unlike most other C compilers, GNU CC allows you to use @samp{-g} with
Unlike most other C compilers, GCC allows you to use @samp{-g} with
@samp{-O}. The shortcuts taken by optimized code may occasionally
produce surprising results: some variables you declared may not exist
at all; flow of control may briefly move where you did not expect it;
@ -1812,7 +1817,7 @@ execute in different places because they were moved out of loops.
Nevertheless it proves possible to debug optimized output. This makes
it reasonable to use the optimizer for programs that might have bugs.
The following options are useful when GNU CC is generated with the
The following options are useful when GCC is generated with the
capability for more than one debugging format.
@item -ggdb
@ -1990,7 +1995,7 @@ frequencies.
@item -fprofile-arcs
Instrument @dfn{arcs} during compilation. For each function of your
program, GNU CC creates a program flow graph, then finds a spanning tree
program, GCC creates a program flow graph, then finds a spanning tree
for the graph. Only arcs that are not on the spanning tree have to be
instrumented: the compiler adds code to count the number of times that these
arcs are executed. When an arc is the only exit or only entrance to a
@ -2020,7 +2025,7 @@ branch probabilities.
@need 2000
@item -ftest-coverage
Create data files for the @code{gcov} code-coverage utility
(@pxref{Gcov,, @code{gcov}: a GNU CC Test Coverage Program}).
(@pxref{Gcov,, @code{gcov}: a GCC Test Coverage Program}).
The data file names begin with the name of your source file:
@table @code
@ -2128,7 +2133,7 @@ unit to @var{file}.
When running a cross-compiler, pretend that the target machine uses the
same floating point format as the host machine. This causes incorrect
output of the actual floating constants, but the actual instruction
sequence will probably be the same as GNU CC would make when running on
sequence will probably be the same as GCC would make when running on
the target machine.
@item -save-temps
@ -2140,7 +2145,7 @@ compiling @file{foo.c} with @samp{-c -save-temps} would produce files
@item -print-file-name=@var{library}
Print the full absolute name of the library file @var{library} that
would be used when linking---and don't do anything else. With this
option, GNU CC does not compile or link anything; it just prints the
option, GCC does not compile or link anything; it just prints the
file name.
@item -print-prog-name=@var{program}
@ -2204,7 +2209,7 @@ without a frame pointer. On some machines the compiler also turns
on other flags.@refill
@item -O2
Optimize even more. GNU CC performs nearly all supported optimizations
Optimize even more. GCC performs nearly all supported optimizations
that do not involve a space-speed tradeoff. The compiler does not
perform loop unrolling or function inlining when you specify @samp{-O2}.
As compared to @samp{-O}, this option increases both compilation time
@ -2342,7 +2347,7 @@ callable version of the function. This switch does not affect
Emit variables declared @code{static const} when optimization isn't turned
on, even if the variables aren't referenced.
GNU CC enables this option by default. If you want to force the compiler to
GCC enables this option by default. If you want to force the compiler to
check if the variable was referenced, regardless of whether or not
optimization is turned on, use the @samp{-fno-keep-static-consts} option.
@ -2423,7 +2428,7 @@ Perform a number of minor optimizations that are relatively expensive.
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
instructions. GNU CC enables this optimization by default with @samp{-O2}
instructions. GCC enables this optimization by default with @samp{-O2}
or higher.
Note @code{-fregmove} and @code{-foptimize-register-moves} are the same
@ -2854,20 +2859,20 @@ mechanism when this option is specified.
@cindex unresolved references and @code{-nodefaultlibs}
One of the standard libraries bypassed by @samp{-nostdlib} and
@samp{-nodefaultlibs} is @file{libgcc.a}, a library of internal subroutines
that GNU CC uses to overcome shortcomings of particular machines, or special
that GCC uses to overcome shortcomings of particular machines, or special
needs for some languages.
@ifset INTERNALS
(@xref{Interface,,Interfacing to GNU CC Output}, for more discussion of
(@xref{Interface,,Interfacing to GCC Output}, for more discussion of
@file{libgcc.a}.)
@end ifset
@ifclear INTERNALS
(@xref{Interface,,Interfacing to GNU CC Output,gcc.info,Porting GNU CC},
(@xref{Interface,,Interfacing to GCC Output,gcc.info,Porting GCC},
for more discussion of @file{libgcc.a}.)
@end ifclear
In most cases, you need @file{libgcc.a} even when you want to avoid
other standard libraries. In other words, when you specify @samp{-nostdlib}
or @samp{-nodefaultlibs} you should usually specify @samp{-lgcc} as well.
This ensures that you have no unresolved references to internal GNU CC
This ensures that you have no unresolved references to internal GCC
library subroutines. (For example, @samp{__main}, used to ensure C++
constructors will be called; @pxref{Collect2,,@code{collect2}}.)
@ -2892,7 +2897,7 @@ this option.
@item -Xlinker @var{option}
Pass @var{option} as an option to the linker. You can use this to
supply system-specific linker options which GNU CC does not know how to
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
@ -3428,24 +3433,24 @@ proper position among the other output files.
@cindex compiler version, specifying
@cindex target machine, specifying
By default, GNU CC compiles code for the same type of machine that you
By default, GCC compiles code for the same type of machine that you
are using. However, it can also be installed as a cross-compiler, to
compile for some other type of machine. In fact, several different
configurations of GNU CC, for different target machines, can be
configurations of GCC, for different target machines, can be
installed side by side. Then you specify which one to use with the
@samp{-b} option.
In addition, older and newer versions of GNU CC can be installed side
In addition, older and newer versions of GCC can be installed side
by side. One of them (probably the newest) will be the default, but
you may sometimes wish to use another.
@table @code
@item -b @var{machine}
The argument @var{machine} specifies the target machine for compilation.
This is useful when you have installed GNU CC as a cross-compiler.
This is useful when you have installed GCC as a cross-compiler.
The value to use for @var{machine} is the same as was specified as the
machine type when configuring GNU CC as a cross-compiler. For
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 @samp{-b i386v} to run that cross compiler.
@ -3454,17 +3459,17 @@ When you do not specify @samp{-b}, it normally means to compile for
the same type of machine that you are using.
@item -V @var{version}
The argument @var{version} specifies which version of GNU CC to run.
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 GNU CC version 2.0.
@var{version} might be @samp{2.0}, meaning to run GCC version 2.0.
The default version, when you do not specify @samp{-V}, is the last
version of GNU CC that you installed.
version of GCC that you installed.
@end table
The @samp{-b} and @samp{-V} options actually work by controlling part of
the file name used for the executable files and libraries used for
compilation. A given version of GNU CC, for a given target machine, is
compilation. A given version of GCC, for a given target machine, is
normally kept in the directory @file{/usr/local/lib/gcc-lib/@var{machine}/@var{version}}.@refill
Thus, sites can customize the effect of @samp{-b} or @samp{-V} either by
@ -3681,13 +3686,13 @@ The @code{rtd} instruction is supported by the 68010, 68020, 68030,
@item -malign-int
@itemx -mno-align-int
Control whether GNU CC aligns @code{int}, @code{long}, @code{long long},
Control whether GCC aligns @code{int}, @code{long}, @code{long long},
@code{float}, @code{double}, and @code{long double} variables on a 32-bit
boundary (@samp{-malign-int}) or a 16-bit boundary (@samp{-mno-align-int}).
Aligning variables on 32-bit boundaries produces code that runs somewhat
faster on processors with 32-bit busses at the expense of more memory.
@strong{Warning:} if you use the @samp{-malign-int} switch, GNU CC will
@strong{Warning:} if you use the @samp{-malign-int} switch, GCC will
align structures containing the above types differently than
most published application binary interface specifications for the m68k.
@ -3755,7 +3760,7 @@ cross-compilation. The embedded targets @samp{sparc-*-aout} and
@samp{-msoft-float} changes the calling convention in the output file;
therefore, it is only useful if you compile @emph{all} of a program with
this option. In particular, you need to compile @file{libgcc.a}, the
library that comes with GNU CC, with @samp{-msoft-float} in order for
library that comes with GCC, with @samp{-msoft-float} in order for
this to work.
@item -mhard-quad-float
@ -3800,7 +3805,7 @@ instructions (except for leaf functions) and is the normal mode of operation.
@itemx -munaligned-doubles
Assume that doubles have 8 byte alignment. This is the default.
With @samp{-munaligned-doubles}, GNU CC assumes that doubles have 8 byte
With @samp{-munaligned-doubles}, GCC assumes that doubles have 8 byte
alignment only if they are contained in another type, or if they have an
absolute address. Otherwise, it assumes they have 4 byte alignment.
Specifying this option avoids some rare compatibility problems with code
@ -3822,7 +3827,7 @@ divide instructions which exist in SPARC v8 but not in SPARC v7.
multiply, integer divide step and scan (@code{ffs}) instructions which
exist in SPARClite but not in SPARC v7.
These options are deprecated and will be deleted in GNU CC 2.9.
These options are deprecated and will be deleted in a future GCC release.
They have been replaced with @samp{-mcpu=xxx}.
@item -mcypress
@ -3837,7 +3842,7 @@ With @samp{-msupersparc} the compiler optimizes code for the SuperSparc cpu, as
used in the SparcStation 10, 1000 and 2000 series. This flag also enables use
of the full SPARC v8 instruction set.
These options are deprecated and will be deleted in GNU CC 2.9.
These options are deprecated and will be deleted in a future GCC release.
They have been replaced with @samp{-mcpu=xxx}.
@item -mcpu=@var{cpu_type}
@ -3951,7 +3956,7 @@ Programs are statically linked, PIC is not supported.
@item -mstack-bias
@itemx -mno-stack-bias
With @samp{-mstack-bias}, GNU CC assumes that the stack pointer, and
With @samp{-mstack-bias}, GCC assumes that the stack pointer, and
frame pointer if present, are offset by -2047 which must be added back
when making stack frame references.
Otherwise, assume no such offset is present.
@ -4118,7 +4123,7 @@ not pass @samp{-assert pure-text} to the linker when linking a shared object.
@item -msoft-float
@kindex -msoft-float
Generate output containing library calls for floating point.
@strong{Warning:} the requisite libraries are not part of GNU CC.
@strong{Warning:} the requisite libraries are not part of GCC.
Normally the facilities of the machine's usual C compiler are used, but
this can't be done directly in cross-compilation. You must make your
own arrangements to provide suitable library functions for
@ -4227,7 +4232,7 @@ cross-compilation.
@samp{-msoft-float} changes the calling convention in the output file;
therefore, it is only useful if you compile @emph{all} of a program with
this option. In particular, you need to compile @file{libgcc.a}, the
library that comes with GNU CC, with @samp{-msoft-float} in order for
library that comes with GCC, with @samp{-msoft-float} in order for
this to work.
@item -mlittle-endian
@ -4623,7 +4628,7 @@ Control how function arguments are stored in stack frames.
@samp{-moptimize-arg-area} saves space by optimizing them, but this
conflicts with the 88open specifications. The opposite alternative,
@samp{-mno-optimize-arg-area}, agrees with 88open standards. By default
GNU CC does not optimize the argument area.
GCC does not optimize the argument area.
@item -mshort-data-@var{num}
@kindex -mshort-data-@var{num}
@ -4683,7 +4688,7 @@ Which variant of the assembler syntax to emit.
@samp{-msvr4} makes the C preprocessor recognize @samp{#pragma weak}
that is used on System V release 4.
@item
@samp{-msvr4} makes GNU CC issue additional declaration directives used in
@samp{-msvr4} makes GCC issue additional declaration directives used in
SVr4.
@end enumerate
@ -4754,7 +4759,7 @@ particular, the behavior of such a division with and without
@cindex bit shift overflow (88k)
@cindex large bit shifts (88k)
Include code to detect bit-shifts of more than 31 bits; respectively,
trap such shifts or emit code to handle them properly. By default GNU CC
trap such shifts or emit code to handle them properly. By default GCC
makes no special provision for large bit shifts.
@item -mwarn-passed-structs
@ -4763,7 +4768,7 @@ makes no special provision for large bit shifts.
Warn when a function passes a struct as an argument or result.
Structure-passing conventions have changed during the evolution of the C
language, and are often the source of portability problems. By default,
GNU CC issues no such warning.
GCC issues no such warning.
@end table
@node RS/6000 and PowerPC Options
@ -4791,7 +4796,7 @@ These @samp{-m} options are defined for the IBM RS/6000 and PowerPC:
@kindex -mpowerpc-gpopt
@kindex -mpowerpc-gfxopt
@kindex -mpowerpc64
GNU CC supports two related instruction set architectures for the
GCC supports two related instruction set architectures for the
RS/6000 and PowerPC. The @dfn{POWER} instruction set are those
instructions supported by the @samp{rios} chip set used in the original
RS/6000 systems and the @dfn{PowerPC} instruction set is the
@ -4804,36 +4809,36 @@ register is included in processors supporting the POWER architecture.
You use these options to specify which instructions are available on the
processor you are using. The default value of these options is
determined when configuring GNU CC. Specifying the
determined when configuring GCC. Specifying the
@samp{-mcpu=@var{cpu_type}} overrides the specification of these
options. We recommend you use the @samp{-mcpu=@var{cpu_type}} option
rather than the options listed above.
The @samp{-mpower} option allows GNU CC to generate instructions that
The @samp{-mpower} option allows GCC to generate instructions that
are found only in the POWER architecture and to use the MQ register.
Specifying @samp{-mpower2} implies @samp{-power} and also allows GNU CC
Specifying @samp{-mpower2} implies @samp{-power} and also allows GCC
to generate instructions that are present in the POWER2 architecture but
not the original POWER architecture.
The @samp{-mpowerpc} option allows GNU CC to generate instructions that
The @samp{-mpowerpc} option allows GCC to generate instructions that
are found only in the 32-bit subset of the PowerPC architecture.
Specifying @samp{-mpowerpc-gpopt} implies @samp{-mpowerpc} and also allows
GNU CC to use the optional PowerPC architecture instructions in the
GCC to use the optional PowerPC architecture instructions in the
General Purpose group, including floating-point square root. Specifying
@samp{-mpowerpc-gfxopt} implies @samp{-mpowerpc} and also allows GNU CC to
@samp{-mpowerpc-gfxopt} implies @samp{-mpowerpc} and also allows GCC to
use the optional PowerPC architecture instructions in the Graphics
group, including floating-point select.
The @samp{-mpowerpc64} option allows GNU CC to generate the additional
The @samp{-mpowerpc64} option allows GCC to generate the additional
64-bit instructions that are found in the full PowerPC64 architecture
and to treat GPRs as 64-bit, doubleword quantities. GNU CC defaults to
and to treat GPRs as 64-bit, doubleword quantities. GCC defaults to
@samp{-mno-powerpc64}.
If you specify both @samp{-mno-power} and @samp{-mno-powerpc}, GNU CC
If you specify both @samp{-mno-power} and @samp{-mno-powerpc}, GCC
will use only the instructions in the common subset of both
architectures plus some special AIX common-mode calls, and will not use
the MQ register. Specifying both @samp{-mpower} and @samp{-mpowerpc}
permits GNU CC to use any instruction from either architecture and to
permits GCC to use any instruction from either architecture and to
allow use of the MQ register; specify this for the Motorola MPC601.
@item -mnew-mnemonics
@ -4845,10 +4850,10 @@ Select which mnemonics to use in the generated assembler code.
defined for the PowerPC architecture, while @samp{-mold-mnemonics}
requests the assembler mnemonics defined for the POWER architecture.
Instructions defined in only one architecture have only one mnemonic;
GNU CC uses that mnemonic irrespective of which of these options is
GCC uses that mnemonic irrespective of which of these options is
specified.
GNU CC defaults to the mnemonics appropriate for the architecture in
GCC defaults to the mnemonics appropriate for the architecture in
use. Specifying @samp{-mcpu=@var{cpu_type}} sometimes overrides the
value of these option. Unless you are building a cross-compiler, you
should normally not specify either @samp{-mnew-mnemonics} or
@ -4886,9 +4891,9 @@ enable the @samp{-mpowerpc} option and disable the @samp{-mpower} option.
AIX versions 4 or greater selects @samp{-mcpu=common} by default, so
that code will operate on all members of the RS/6000 POWER and PowerPC
families. In that case, GNU CC will use only the instructions in the
families. In that case, GCC will use only the instructions in the
common subset of both architectures plus some special AIX common-mode
calls, and will not use the MQ register. GNU CC assumes a generic
calls, and will not use the MQ register. GCC assumes a generic
processor model for scheduling purposes.
Specifying any of the options @samp{-mcpu=rios1}, @samp{-mcpu=rios2},
@ -4918,25 +4923,25 @@ instruction scheduling parameters.
@kindex -mminimal-toc
Modify generation of the TOC (Table Of Contents), which is created for
every executable file. The @samp{-mfull-toc} option is selected by
default. In that case, GNU CC will allocate at least one TOC entry for
each unique non-automatic variable reference in your program. GNU CC
default. In that case, GCC will allocate at least one TOC entry for
each unique non-automatic variable reference in your program. GCC
will also place floating-point constants in the TOC. However, only
16,384 entries are available in the TOC.
If you receive a linker error message that saying you have overflowed
the available TOC space, you can reduce the amount of TOC space used
with the @samp{-mno-fp-in-toc} and @samp{-mno-sum-in-toc} options.
@samp{-mno-fp-in-toc} prevents GNU CC from putting floating-point
constants in the TOC and @samp{-mno-sum-in-toc} forces GNU CC to
@samp{-mno-fp-in-toc} prevents GCC from putting floating-point
constants in the TOC and @samp{-mno-sum-in-toc} forces GCC to
generate code to calculate the sum of an address and a constant at
run-time instead of putting that sum into the TOC. You may specify one
or both of these options. Each causes GNU CC to produce very slightly
or both of these options. Each causes GCC to produce very slightly
slower and larger code at the expense of conserving TOC space.
If you still run out of space in the TOC even when you specify both of
these options, specify @samp{-mminimal-toc} instead. This option causes
GNU CC to make only one TOC entry for every file. When you specify this
option, GNU CC will produce code that is slower and larger but which
GCC to make only one TOC entry for every file. When you specify this
option, GCC will produce code that is slower and larger but which
uses extremely little TOC space. You may wish to use this option
only on files that contain less frequently executed code. @refill
@ -4948,7 +4953,7 @@ Enable 64-bit PowerPC ABI and calling convention: 64-bit pointers, 64-bit
@code{long} type, and the infrastructure needed to support them.
Specifying @samp{-m64} implies @samp{-mpowerpc64} and
@samp{-mpowerpc}, while @samp{-m32} disables the 64-bit ABI and
implies @samp{-mno-powerpc64}. GNU CC defaults to @samp{-m32}.
implies @samp{-mno-powerpc64}. GCC defaults to @samp{-m32}.
@item -mxl-call
@itemx -mno-xl-call
@ -4987,7 +4992,7 @@ option are incompatible.
@kindex -msoft-float
Generate code that does not use (uses) the floating-point register set.
Software floating point emulation is provided if you use the
@samp{-msoft-float} option, and pass the option to GNU CC when linking.
@samp{-msoft-float} option, and pass the option to GCC when linking.
@item -mmultiple
@itemx -mno-multiple
@ -5411,7 +5416,7 @@ prevents compilation.
@item -msoft-float
Generate output containing library calls for floating point.
@strong{Warning:} the requisite libraries are not part of GNU CC.
@strong{Warning:} the requisite libraries are not part of GCC.
Normally the facilities of the machine's usual C compiler are used, but
this can't be done directly in cross-compilation. You must make your
own arrangements to provide suitable library functions for
@ -5555,7 +5560,7 @@ comparison is unordered.
@item -msoft-float
Generate output containing library calls for floating point.
@strong{Warning:} the requisite libraries are not part of GNU CC.
@strong{Warning:} the requisite libraries are not part of GCC.
Normally the facilities of the machine's usual C compiler are used, but
this can't be done directly in cross-compilation. You must make your
own arrangements to provide suitable library functions for
@ -5585,7 +5590,7 @@ also use the @samp{-ffast-math} switch.
@item -malign-double
@itemx -mno-align-double
Control whether GNU CC aligns @code{double}, @code{long double}, and
Control whether GCC aligns @code{double}, @code{long double}, and
@code{long long} variables on a two word boundary or a one word
boundary. Aligning @code{double} variables on a two word boundary will
produce code that runs somewhat faster on a @samp{Pentium} at the
@ -5597,13 +5602,13 @@ the published application binary interface specifications for the 386.
@item -msvr3-shlib
@itemx -mno-svr3-shlib
Control whether GNU CC places uninitialized locals into @code{bss} or
Control whether GCC places uninitialized locals into @code{bss} or
@code{data}. @samp{-msvr3-shlib} places these locals into @code{bss}.
These options are meaningful only on System V Release 3.
@item -mno-wide-multiply
@itemx -mwide-multiply
Control whether GNU CC uses the @code{mul} and @code{imul} that produce
Control whether GCC uses the @code{mul} and @code{imul} that produce
64 bit results in @code{eax:edx} from 32 bit operands to do @code{long
long} multiplies and 32-bit division by constants.
@ -5790,7 +5795,7 @@ does provide software floating point support.
@samp{-msoft-float} changes the calling convention in the output file;
therefore, it is only useful if you compile @emph{all} of a program with
this option. In particular, you need to compile @file{libgcc.a}, the
library that comes with GNU CC, with @samp{-msoft-float} in order for
library that comes with GCC, with @samp{-msoft-float} in order for
this to work.
@end table
@ -6009,7 +6014,7 @@ rounding towards plus infinity. Thus, unless your program modifies the
In the Alpha architecture, floating point traps are imprecise. This
means without software assistance it is impossible to recover from a
floating trap and program execution normally needs to be terminated.
GNU CC can generate code that can assist operating system trap handlers
GCC can generate code that can assist operating system trap handlers
in determining the exact location that caused a floating point trap.
Depending on the requirements of an application, different levels of
precisions can be selected:
@ -6040,12 +6045,12 @@ generated assembly file. Under DEC Unix, this has the effect that
IEEE-conformant math library routines will be linked in.
@item -mbuild-constants
Normally GNU CC examines a 32- or 64-bit integer constant to
Normally GCC 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 segment at runtime.
Use this option to require GNU CC to construct @emph{all} integer constants
Use this option to require GCC 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
@ -6063,19 +6068,19 @@ assembler (@samp{-malpha-as}) or by the GNU assembler @samp{-mgas}.
@itemx -mno-cix
@itemx -mmax
@itemx -mno-max
Indicate whether GNU CC should generate code to use the optional BWX,
Indicate whether GCC 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.
of the CPU on which GCC was built if none was specified.
@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
@samp{EV} style name or the corresponding chip number. GCC
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.
GCC will default to the processor on which the compiler was built.
Supported values for @var{cpu_type} are
@ -6596,7 +6601,7 @@ programs that don't use exception handling.
Return ``short'' @code{struct} and @code{union} values in memory like
longer ones, rather than in registers. This convention is less
efficient, but it has the advantage of allowing intercallability between
GNU CC-compiled files and files compiled with other compilers.
GCC-compiled files and files compiled with other compilers.
The precise convention for returning structures in memory depends
on the target configuration macros.
@ -6610,9 +6615,9 @@ returned in registers when possible. This is more efficient for small
structures than @samp{-fpcc-struct-return}.
If you specify neither @samp{-fpcc-struct-return} nor its contrary
@samp{-freg-struct-return}, GNU CC defaults to whichever convention is
standard for the target. If there is no standard convention, GNU CC
defaults to @samp{-fpcc-struct-return}, except on targets where GNU CC
@samp{-freg-struct-return}, GCC defaults to whichever convention is
standard for the target. If there is no standard convention, GCC
defaults to @samp{-fpcc-struct-return}, except on targets where GCC
is the principal compiler. In those cases, we can choose the standard,
and we chose the more efficient register return alternative.
@ -6648,7 +6653,7 @@ destructors) in the form used by the GNU linker (on systems where the GNU
linker is the standard method of handling them). Use this option when
you want to use a non-GNU linker, which also requires using the
@code{collect2} program to make sure the system linker includes
constructors and destructors. (@code{collect2} is included in the GNU CC
constructors and destructors. (@code{collect2} is included in the GCC
distribution.) For systems which @emph{must} use @code{collect2}, the
compiler driver @code{gcc} is configured to do this automatically.
@ -6674,7 +6679,7 @@ Consider all memory references through pointers to be volatile.
@item -fvolatile-global
Consider all memory references to extern and global data items to
be volatile. GNU CC does not consider static data items to be volatile
be volatile. GCC does not consider static data items to be volatile
because of this switch.
@item -fvolatile-static
@ -6687,7 +6692,7 @@ Generate position-independent code (PIC) suitable for use in a shared
library, if supported for the target machine. Such code accesses all
constant addresses through a global offset table (GOT). The dynamic
loader resolves the GOT entries when the program starts (the dynamic
loader is not part of GNU CC; it is part of the operating system). If
loader is not part of GCC; it is part of the operating system). If
the GOT size for the linked executable exceeds a machine-specific
maximum size, you get an error message from the linker indicating that
@samp{-fpic} does not work; in that case, recompile with @samp{-fPIC}
@ -6695,7 +6700,7 @@ instead. (These maximums are 16k on the m88k, 8k on the Sparc, and 32k
on the m68k and RS/6000. The 386 has no such limit.)
Position-independent code requires special support, and therefore works
only on certain machines. For the 386, GNU CC supports PIC for System V
only on certain machines. For the 386, GCC supports PIC for System V
but not for the Sun 386i. Code generated for the IBM RS/6000 is always
position-independent.
@ -6755,7 +6760,7 @@ not want to use this option, since it makes the code suboptimal, and
the offsets of structure members won't agree with system libraries.
@item -fcheck-memory-usage
Generate extra code to check each memory access. GNU CC will generate
Generate extra code to check each memory access. GCC will generate
code that is suitable for a detector of bad memory accesses such as
@file{Checker}.
@ -6770,7 +6775,7 @@ 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 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
@samp{-fprefix-function-name} option, which requests GCC 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
@ -6796,8 +6801,8 @@ These calls would be similar to those done in the stubs described above.
@c should be documented!
@item -fprefix-function-name
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
Request GCC to add a prefix to the symbols generated for function names.
GCC 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 stubs are used.
@ -6812,7 +6817,7 @@ foo (int a)
@end example
@noindent
GNU CC will compile the code as if it was written:
GCC will compile the code as if it was written:
@example
extern void prefix_bar (int);
void
@ -6893,11 +6898,11 @@ option, and that not all targets provide complete support for it.
@end table
@node Environment Variables
@section Environment Variables Affecting GNU CC
@section Environment Variables Affecting GCC
@cindex environment variables
This section describes several environment variables that affect how GNU
CC operates. Some of them work by specifying directories or prefixes to use
This section describes several environment variables that affect how GCC
operates. Some of them work by specifying directories or prefixes to use
when searching for various kinds of files. Some are used to specify other
aspects of the compilation environment.
@ -6905,15 +6910,15 @@ aspects of the compilation environment.
Note that you can also specify places to search using options such as
@samp{-B}, @samp{-I} and @samp{-L} (@pxref{Directory Options}). These
take precedence over places specified using environment variables, which
in turn take precedence over those specified by the configuration of GNU
CC.
in turn take precedence over those specified by the configuration of GCC.
@end ifclear
@ifset INTERNALS
Note that you can also specify places to search using options such as
@samp{-B}, @samp{-I} and @samp{-L} (@pxref{Directory Options}). These
take precedence over places specified using environment variables, which
in turn take precedence over those specified by the configuration of GNU
CC. @xref{Driver}.
in turn take precedence over those specified by the configuration of GCC.
@xref{Driver}.
@end ifset
@table @code
@ -6934,16 +6939,16 @@ CC. @xref{Driver}.
@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
These environment variables control the way that GCC uses
localization information that allow GCC to work with different
national conventions. GCC 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
classification. GCC 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.
@ -6954,13 +6959,13 @@ 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
environment variable. If none of these variables are set, GCC
defaults to traditional C English behavior.
@item TMPDIR
@findex TMPDIR
If @code{TMPDIR} is set, it specifies the directory to use for temporary
files. GNU CC uses temporary files to hold the output of one stage of
files. GCC uses temporary files to hold the output of one stage of
compilation which is to be used as input to the next stage: for example,
the output of the preprocessor, which is the input to the compiler
proper.
@ -6972,7 +6977,7 @@ names of the subprograms executed by the compiler. No slash is added
when this prefix is combined with the name of a subprogram, but you can
specify a prefix that ends with a slash if you wish.
If GNU CC cannot find the subprogram using the specified prefix, it
If GCC cannot find the subprogram using the specified prefix, it
tries looking in the usual places for the subprogram.
The default value of @code{GCC_EXEC_PREFIX} is
@ -6987,9 +6992,9 @@ used for linking.
In addition, the prefix is used in an unusual way in finding the
directories to search for header files. For each of the standard
directories whose name normally begins with @samp{/usr/local/lib/gcc-lib}
(more precisely, with the value of @code{GCC_INCLUDE_DIR}), GNU CC tries
(more precisely, with the value of @code{GCC_INCLUDE_DIR}), GCC tries
replacing that beginning with the specified prefix to produce an
alternate directory name. Thus, with @samp{-Bfoo/}, GNU CC will search
alternate directory name. Thus, with @samp{-Bfoo/}, GCC will search
@file{foo/bar} where it would normally search @file{/usr/local/lib/bar}.
These alternate directories are searched first; the standard directories
come next.
@ -6997,7 +7002,7 @@ come next.
@item COMPILER_PATH
@findex COMPILER_PATH
The value of @code{COMPILER_PATH} is a colon-separated list of
directories, much like @code{PATH}. GNU CC tries the directories thus
directories, much like @code{PATH}. GCC tries the directories thus
specified when searching for subprograms, if it can't find the
subprograms using @code{GCC_EXEC_PREFIX}.
@ -7005,9 +7010,9 @@ subprograms using @code{GCC_EXEC_PREFIX}.
@findex LIBRARY_PATH
The value of @code{LIBRARY_PATH} is a colon-separated list of
directories, much like @code{PATH}. When configured as a native compiler,
GNU CC tries the directories thus specified when searching for special
GCC tries the directories thus specified when searching for special
linker files, if it can't find them using @code{GCC_EXEC_PREFIX}. Linking
using GNU CC also uses these directories when searching for ordinary
using GCC also uses these directories when searching for ordinary
libraries for the @samp{-l} option (but directories specified with
@samp{-L} come first).
@ -7020,7 +7025,7 @@ libraries for the @samp{-l} option (but directories specified with
@c @itemx OBJCPLUS_INCLUDE_PATH
These environment variables pertain to particular languages. Each
variable's value is a colon-separated list of directories, much like
@code{PATH}. When GNU CC searches for header files, it tries the
@code{PATH}. When GCC searches for header files, it tries the
directories listed in the variable for the language you are using, after
the directories specified with @samp{-I} but before the standard header
file directories.
@ -7113,9 +7118,9 @@ original source file. The original file is renamed to a name ending
with @samp{.save}. If the @samp{.save} file already exists, then
the source file is simply discarded.
@code{protoize} and @code{unprotoize} both depend on GNU CC itself to
@code{protoize} and @code{unprotoize} both depend on GCC itself to
scan the program and collect information about the functions it uses.
So neither of these programs will work until GNU CC is installed.
So neither of these programs will work until GCC is installed.
Here is a table of the options you can use with @code{protoize} and
@code{unprotoize}. Each option works with both programs unless