* doc/install.texi (sparc-*-linux*): Mention requirements for

[pf3gnuchains/gcc-fork.git] / gcc / doc / install.texi

\input texinfo.tex    @c -*-texinfo-*-
@c @ifnothtml
@c %**start of header
@setfilename install.info
@settitle Installing GCC
@setchapternewpage odd
@c %**end of header
@c @end ifnothtml

@c Specify title for specific html page
@ifset indexhtml
@settitle Installing GCC
@end ifset
@ifset specifichtml
@settitle Host/Target specific installation notes for GCC
@end ifset
@ifset downloadhtml
@settitle Downloading GCC
@end ifset
@ifset configurehtml
@settitle Installing GCC: Configuration
@end ifset
@ifset buildhtml
@settitle Installing GCC: Building
@end ifset
@ifset testhtml
@settitle Installing GCC: Testing
@end ifset
@ifset finalinstallhtml
@settitle Installing GCC: Final installation
@end ifset
@ifset binarieshtml
@settitle Installing GCC: Binaries
@end ifset

@c Copyright (C) 2001 Free Software Foundation, Inc.
@c *** Converted to texinfo by Dean Wakerley, dean@wakerley.com

@c Include everything if we're not making html
@ifnothtml
@set indexhtml
@set specifichtml
@set downloadhtml
@set configurehtml
@set buildhtml
@set testhtml
@set finalinstallhtml
@set binarieshtml
@end ifnothtml

@c Part 2 Summary Description and Copyright
@ifinfo

Copyright @copyright{} 2001 Free Software Foundation, Inc.
@end ifinfo

@c Part 3 Titlepage and Copyright
@titlepage
@sp 10
@comment The title is printed in a large font.
@center @titlefont{Installing GCC}

@c The following two commands start the copyright page.
@page
@vskip 0pt plus 1filll
Copyright @copyright{} 2001 Free Software Foundation, Inc.
@end titlepage

@c Part 4 Top node and Master Menu
@ifinfo
@node    Top, , , (dir)
@comment node-name, next,          Previous, up

@menu
* Installing GCC::  This document describes the generic installation
                    procedure for GCC as well as detailing some target
                    specific installation instructions.

* Specific::        Host/target specific installation notes for GCC.
* Binaries::        Where to get pre-compiled binaries.

* Concept Index::   This index has two entries.
@end menu
@end ifinfo

@c Part 5 The Body of the Document
@c ***Installing GCC**********************************************************
@ifnothtml
@comment node-name,     next,          previous, up
@node    Installing GCC, Binaries, , Top
@end ifnothtml
@ifset indexhtml
@html
<h1 align="center">Installing GCC</h1>
@end html
@ifnothtml
@chapter Installing GCC
@end ifnothtml

The latest version of this document is always available at
@uref{http://gcc.gnu.org/install/,,http://gcc.gnu.org/install/}.

This document describes the generic installation procedure for GCC as well
as detailing some target specific installation instructions.

GCC includes several components that previously were separate distributions
with their own installation instructions.  This document supersedes all
package specific installation instructions.

@emph{Before} starting the build/install procedure please check the
@ifnothtml
@ref{Specific, host/target specific installation notes}.
@end ifnothtml
@ifhtml
@uref{specific.html,,host/target specific installation notes}.
@end ifhtml
We recommend you browse the entire generic installation instructions before
you proceed.

Lists of successful builds for released versions of GCC are
available at our web pages for
@uref{http://gcc.gnu.org/gcc-3.0/buildstat.html,,3.0}
and
@uref{http://gcc.gnu.org/gcc-2.95/buildstat.html,,2.95}.
These lists are updated as new information becomes available.

The installation procedure itself is broken into five steps.

@ifinfo
@menu
* Downloading the source::
* Configuration::
* Building::
* Testing:: (optional)
* Final install::
@end menu
@end ifinfo
@ifhtml
@enumerate
@item
@uref{download.html,,Downloading the source}
@item
@uref{configure.html,,Configuration}
@item
@uref{build.html,,Building}
@item
@uref{test.html,,Testing} (optional)
@item
@uref{finalinstall.html,,Final install}
@end enumerate
@end ifhtml

Please note that GCC does not support @samp{make uninstall} and probably
won't do so in the near future as this would open a can of worms.  Instead,
we suggest that you install GCC into a directory of its own and simply
remove that directory when you do not need that specific version of GCC
any longer, and, if shared libraries are installed there as well, no
more binaries exist that use them.

@html
<hr>
<p>
@end html
@ifhtml
@uref{./index.html,,Return to the GCC Installation page}
@end ifhtml
@end ifset

@c ***Downloading the source**************************************************
@ifnothtml
@comment node-name,     next,          previous, up
@node    Downloading the source, Configuration, , Installing GCC
@end ifnothtml
@ifset downloadhtml
@html
<h1 align="center">Downloading GCC</h1>
@end html
@ifnothtml
@chapter Downloading GCC
@end ifnothtml
@cindex Downloading GCC
@cindex Downloading the Source

GCC is distributed via @uref{http://gcc.gnu.org/cvs.html,,CVS} and FTP
tarballs compressed with @command{gzip} or
@command{bzip2}.  It is possible to download a full distribution or specific
components.

Please refer to our @uref{http://gcc.gnu.org/releases.html,,releases web page}
for information on how to obtain GCC@.

The full distribution includes the C, C++, Objective-C, Fortran, Java,
and CHILL compilers.  The full distribution also includes runtime libraries
for C++, Objective-C, Fortran, Java and CHILL.  (GCC 3.0 does not
include CHILL.)  In GCC 3.0 and later versions, GNU compiler testsuites
are also included in the full distribution.

If you choose to download specific components, you must download the core
GCC distribution plus any language specific distributions you wish to
use.  The core distribution includes the C language front end as well as the
shared components.  Each language has a tarball which includes the language
front end as well as the language runtime (when appropriate).

Unpack the core distribution as well as any language specific
distributions in the same directory.

If you also intend to build binutils (either to upgrade an existing
installation or for use in place of the corresponding tools of your
OS), unpack the binutils distribution either in the same directory or
a separate one.  In the latter case, add symbolic links to any
components of the binutils you intend to build alongside the compiler
(@file{bfd}, @file{binutils}, @file{gas}, @file{gprof}, @file{ld},
@file{opcodes}, @dots{}) to the directory containing the GCC sources.

@html
<hr>
<p>
@end html
@ifhtml
@uref{./index.html,,Return to the GCC Installation page}
@end ifhtml
@end ifset

@c ***Configuration***********************************************************
@ifnothtml
@comment node-name,     next,          previous, up
@node    Configuration, Building, Downloading the source, Installing GCC
@end ifnothtml
@ifset configurehtml
@html
<h1 align="center">Installing GCC: Configuration</h1>
@end html
@ifnothtml
@chapter Installing GCC: Configuration
@end ifnothtml
@cindex Configuration
@cindex Installing GCC: Configuration

Like most GNU software, GCC must be configured before it can be built.
This document describes the recommended configuration procedure
for both native and cross targets.

We use @var{srcdir} to refer to the toplevel source directory for
GCC; we use @var{objdir} to refer to the toplevel build/object directory.

If you obtained the sources via CVS, @var{srcdir} must refer to the top
@file{gcc} directory, the one where the @file{MAINTAINERS} can be found,
and not its @file{gcc} subdirectory, otherwise the build will fail.

First, we @strong{highly} recommend that GCC be built into a
separate directory than the sources which does @strong{not} reside
within the source tree.  This is how we generally build GCC; building
where @var{srcdir} == @var{objdir} should still work, but doesn't
get extensive testing; building where @var{objdir} is a subdirectory
of @var{srcdir} is unsupported.

If you have previously built GCC in the same directory for a
different target machine, do @samp{make distclean} to delete all files
that might be invalid.  One of the files this deletes is
@file{Makefile}; if @samp{make distclean} complains that @file{Makefile}
does not exist, it probably means that the directory is already suitably
clean.  However, with the recommended method of building in a separate
@var{objdir}, you should simply use a different @var{objdir} for each
target.

Second, when configuring a native system, either @command{cc} or
@command{gcc} must be in your path or you must set @env{CC} in
your environment before running configure.  Otherwise the configuration
scripts may fail.

Note that the bootstrap compiler and the resulting GCC must be link
compatible, else the bootstrap will fail with linker errors about
incompatible object file formats.  Several multilibed targets are
affected by this requirement, see
@ifnothtml
@ref{Specific, host/target specific installation notes}.
@end ifnothtml
@ifhtml
@uref{specific.html,,host/target specific installation notes}.
@end ifhtml

To configure GCC:

@example
   % mkdir @var{objdir}
   % cd @var{objdir}
   % @var{srcdir}/configure [@var{options}] [@var{target}]
@end example


@heading Target specification
@itemize @bullet
@item
GCC has code to correctly determine the correct value for @var{target}
for nearly all native systems.  Therefore, we highly recommend you not
provide a configure target when configuring a native compiler.

@item
@var{target} must be specified as @option{--target=@var{target}}
when configuring a cross compiler; examples of valid targets would be
i960-rtems, m68k-coff, sh-elf, etc.

@item
Specifying just @var{target} instead of @option{--target=@var{target}}
implies that the host defaults to @var{target}.
@end itemize


@heading Options specification

Use @var{options} to override several configure time options for
GCC@.  A list of supported @var{options} follows; @command{configure
--help} may list other options, but those not listed below may not
work and should not normally be used.

@table @code
@item --prefix=@var{dirname}
Specify the toplevel installation
directory.  This is the recommended way to install the tools into a directory
other than the default.  The toplevel installation directory defaults to
@file{/usr/local}.

We @strong{highly} recommend against @var{dirname} being the same or a
subdirectory of @var{objdir} or vice versa.

These additional options control where certain parts of the distribution
are installed.  Normally you should not need to use these options.
@table @code

@item --exec-prefix=@var{dirname}
Specify the toplevel installation directory for architecture-dependent
files.  The default is @file{@var{prefix}}.

@item --bindir=@var{dirname}
Specify the installation directory for the executables called by users
(such as @command{gcc} and @command{g++}).  The default is
@file{@var{exec-prefix}/bin}.

@item --libdir=@var{dirname}
Specify the installation directory for object code libraries and
internal parts of GCC@.  The default is @file{@var{exec-prefix}/lib}.

@item --with-slibdir=@var{dirname}
Specify the installation directory for the shared libgcc library.  The
default is @file{@var{libdir}}.

@item --infodir=@var{dirname}
Specify the installation directory for documentation in info format.
The default is @file{@var{prefix}/info}.

@item --mandir=@var{dirname}
Specify the installation directory for manual pages.  The default is
@file{@var{prefix}/man}.  (Note that the manual pages are only extracts from
the full GCC manuals, which are provided in Texinfo format.  The
@command{g77} manpage is unmaintained and may be out of date; the others
are derived by an automatic conversion process from parts of the full
manual.)

@item --with-gxx-include-dir=@var{dirname}
Specify
the installation directory for G++ header files.  The default is
@file{@var{prefix}/include/g++-v3}.

@end table

@item --program-prefix=@var{prefix}
GCC supports some transformations of the names of its programs when
installing them. This option prepends @var{prefix} to the names of
programs to install in @var{bindir} (see above). For example, specifying
@option{--program-prefix=foo-} would result in @samp{gcc}
being installed as @file{/usr/local/bin/foo-gcc}.

@item --program-suffix=@var{suffix}
Appends @var{suffix} to the names of programs to install in @var{bindir}
(see above). For example, specifying @option{--program-suffix=-3.1}
would result in @samp{gcc} being installed as
@file{/usr/local/bin/gcc-3.1}.

@item --program-transform-name=@var{pattern}
Applies the @samp{sed} script @var{pattern} to be applied to the names
of programs to install in @var{bindir} (see above). @var{pattern} has to
consist of one or more basic @samp{sed} editing commands, separated by
semicolons. For example, if you want the @samp{gcc} program name to be
transformed to the installed program @file{/usr/local/bin/myowngcc} and
the @samp{g++} program name to be transformed to
@file{/usr/local/bin/gspecial++} without changing other program names,
you could use the pattern
@option{--program-transform-name='s/^gcc$/myowngcc/; s/^g++$/gspecial++/'}
to achieve this effect.

All three options can be combined and used together, resulting in more
complex conversion patterns. As a basic rule, @var{prefix} (and
@var{suffix}) are prepended (appended) before further transformations
can happen with a special transformation script @var{pattern}.

As currently implemented, this options only take effect for native
builds; cross compiler binaries' names are not transformed even when a
transformation is explicitly asked for by one of this options.

For native builds, some of the installed programs are also installed
with the target alias in front of their name, as in
@samp{i686-pc-linux-gnu-gcc}. All of the above transformations happen
before the target alias is prepended to the name - so, specifying
@option{--program-prefix=foo-} and @option{program-suffix=-3.1}, the
resulting binary would be installed as
@file{/usr/local/bin/i686-pc-linux-gnu-foo-gcc-3.1}.

As a last shortcoming, none of the installed CHILL and Ada programs are
transformed yet, which will be fixed in some time.

@item --with-local-prefix=@var{dirname}
Specify the
installation directory for local include files.  The default is
@file{/usr/local}.  Specify this option if you want the compiler to
search directory @file{@var{dirname}/include} for locally installed
header files @emph{instead} of @file{/usr/local/include}.

You should specify @option{--with-local-prefix} @strong{only} if your
site has a different convention (not @file{/usr/local}) for where to put
site-specific files.

The default value for @option{--with-local-prefix} is @file{/usr/local}
regardless of the value of @option{--prefix}.  Specifying
@option{--prefix} has no effect on which directory GCC searches for
local header files.  This may seem counterintuitive, but actually it is
logical.

The purpose of @option{--prefix} is to specify where to @emph{install
GCC}.  The local header files in @file{/usr/local/include}---if you put
any in that directory---are not part of GCC@.  They are part of other
programs---perhaps many others.  (GCC installs its own header files in
another directory which is based on the @option{--prefix} value.)

@strong{Do not} specify @file{/usr} as the @option{--with-local-prefix}!
The directory you use for @option{--with-local-prefix} @strong{must not}
contain any of the system's standard header files.  If it did contain
them, certain programs would be miscompiled (including GNU Emacs, on
certain targets), because this would override and nullify the header
file corrections made by the @code{fixincludes} script.

Indications are that people who use this option use it based on mistaken
ideas of what it is for.  People use it as if it specified where to
install part of GCC@.  Perhaps they make this assumption because
installing GCC creates the directory.

@item --enable-shared[=@var{package}[,@dots{}]]
Build shared versions of libraries, if shared libraries are supported on
the target platform.  Unlike GCC 2.95.x and earlier, shared libraries
are enabled by default on all platforms that support shared libraries,
except for @samp{libobjc} which is built as a static library only by
default.

If a list of packages is given as an argument, build shared libraries
only for the listed packages.  For other packages, only static libraries
will be built.  Package names currently recognized in the GCC tree are
@samp{libgcc} (also known as @samp{gcc}), @samp{libstdc++} (not
@samp{libstdc++-v3}), @samp{libffi}, @samp{zlib}, @samp{boehm-gc} and
@samp{libjava}.  Note that @samp{libobjc} does not recognize itself by
any name, so, if you list package names in @option{--enable-shared},
you will only get static Objective-C libraries.  @samp{libf2c} and
@samp{libiberty} do not support shared libraries at all.

Use @option{--disable-shared} to build only static libraries.  Note that
@option{--disable-shared} does not accept a list of package names as
argument, only @option{--enable-shared} does.

@item @anchor{with-gnu-as}--with-gnu-as
Specify that the compiler should assume that the
assembler it finds is the GNU assembler.  However, this does not modify
the rules to find an assembler and will result in confusion if found
assembler is not actually the GNU assembler.  (Confusion will also
result if the compiler finds the GNU assembler but has not been
configured with @option{--with-gnu-as}.)  If you have more than one
assembler installed on your system, you may want to use this option in
connection with @option{--with-as=@var{pathname}}.

The systems where it makes a difference whether you use the GNU assembler are
@samp{hppa1.0-@var{any}-@var{any}}, @samp{hppa1.1-@var{any}-@var{any}},
@samp{i386-@var{any}-sysv}, @samp{i386-@var{any}-isc},
@samp{i860-@var{any}-bsd}, @samp{m68k-bull-sysv},
@samp{m68k-hp-hpux}, @samp{m68k-sony-bsd},
@samp{m68k-altos-sysv}, @samp{m68000-hp-hpux},
@samp{m68000-att-sysv}, @samp{@var{any}-lynx-lynxos},
and @samp{mips-@var{any}}.
On any other system, @option{--with-gnu-as} has no effect.

On the systems listed above (except for the HP-PA, for ISC on the
386, and for @samp{mips-sgi-irix5.*}), if you use the GNU assembler,
you should also use the GNU linker (and specify @option{--with-gnu-ld}).

@item --with-as=@var{pathname}
Specify that the
compiler should use the assembler pointed to by @var{pathname}, rather
than the one found by the standard rules to find an assembler, which
are:
@itemize @bullet
@item
Check the
@file{@var{exec_prefix}/lib/gcc-lib/@var{target}/@var{version}}
directory, where @var{exec_prefix} defaults to @var{prefix} which
defaults to @file{/usr/local} unless overridden by the
@option{--prefix=@var{pathname}} switch described above. @var{target} is the
target system triple, such as @samp{sparc-sun-solaris2.7}, and
@var{version} denotes the GCC version, such as 3.0.
@item
Check operating system specific directories (e.g.@: @file{/usr/ccs/bin} on
Sun Solaris 2).
@end itemize
Note that these rules do not check for the value of @env{PATH}.  You may
want to use @option{--with-as} if no assembler is installed in the
directories listed above, or if you have multiple assemblers installed
and want to choose one that is not found by the above rules.

@item @anchor{with-gnu-ld}--with-gnu-ld
Same as @uref{#with-gnu-as,,@option{--with-gnu-as}}
but for linker.


@item --with-ld=@var{pathname}
Same as
@option{--with-as}, but for the linker.

@item --with-stabs
Specify that stabs debugging
information should be used instead of whatever format the host normally
uses.  Normally GCC uses the same debug format as the host system.

On MIPS based systems and on Alphas, you must specify whether you want
GCC to create the normal ECOFF debugging format, or to use BSD-style
stabs passed through the ECOFF symbol table.  The normal ECOFF debug
format cannot fully handle languages other than C@.  BSD stabs format can
handle other languages, but it only works with the GNU debugger GDB@.

Normally, GCC uses the ECOFF debugging format by default; if you
prefer BSD stabs, specify @option{--with-stabs} when you configure GCC@.

No matter which default you choose when you configure GCC, the user
can use the @option{-gcoff} and @option{-gstabs+} options to specify explicitly
the debug format for a particular compilation.

@option{--with-stabs} is meaningful on the ISC system on the 386, also, if
@option{--with-gas} is used.  It selects use of stabs debugging
information embedded in COFF output.  This kind of debugging information
supports C++ well; ordinary COFF debugging information does not.

@option{--with-stabs} is also meaningful on 386 systems running SVR4.  It
selects use of stabs debugging information embedded in ELF output.  The
C++ compiler currently (2.6.0) does not support the DWARF debugging
information normally used on 386 SVR4 platforms; stabs provide a
workable alternative.  This requires gas and gdb, as the normal SVR4
tools can not generate or interpret stabs.

@item --disable-multilib
Specify that multiple target
libraries to support different target variants, calling
conventions, etc should not be built.  The default is to build a
predefined set of them.

Some targets provide finer-grained control over which multilibs are built
(e.g., @option{--disable-softfloat}):
@table @code

@item arc-*-elf*
biendian.

@item arm-*-*
fpu, 26bit, underscore, interwork, biendian, nofmult.

@item m68*-*-*
softfloat, m68881, m68000, m68020.

@item mips*-*-*
single-float, biendian, softfloat.

@item powerpc*-*-*, rs6000*-*-*
aix64, pthread, softfloat, powercpu, powerpccpu, powerpcos, biendian,
sysv, aix. 

@end table

@item --enable-threads
Specify that the target
supports threads.  This affects the Objective-C compiler and runtime
library, and exception handling for other languages like C++ and Java.
On some systems, this is the default.

In general, the best (and, in many cases, the only known) threading
model available will be configured for use.  Beware that on some
systems, gcc has not been taught what threading models are generally
available for the system.  In this case, @option{--enable-threads} is an
alias for @option{--enable-threads=single}.

@item --disable-threads
Specify that threading support should be disabled for the system.
This is an alias for @option{--enable-threads=single}.

@item --enable-threads=@var{lib}
Specify that
@var{lib} is the thread support library.  This affects the Objective-C
compiler and runtime library, and exception handling for other languages
like C++ and Java.  The possibilities for @var{lib} are:

@table @code
@item aix
AIX thread support.
@item dce
DCE thread support.
@item mach
Generic MACH thread support, known to work on NeXTSTEP@.  (Please note
that the file needed to support this configuration, @file{gthr-mach.h}, is
missing and thus this setting will cause a known bootstrap failure.)
@item no
This is an alias for @samp{single}.
@item posix
Generic POSIX thread support.
@item pthreads
Same as @samp{posix} on arm*-*-linux*, *-*-chorusos* and *-*-freebsd*
only.  A future release of gcc might remove this alias or extend it
to all platforms.
@item rtems
RTEMS thread support.
@item single
Disable thread support, should work for all platforms.
@item solaris
Sun Solaris 2 thread support.
@item vxworks
VxWorks thread support.
@item win32
Microsoft Win32 API thread support.
@end table

@item --with-cpu=@var{cpu}
Specify which cpu variant the
compiler should generate code for by default.  This is currently
only supported on the some ports, specifically arm, powerpc, and
SPARC@.  If configure does not recognize the model name (e.g.@: arm700,
603e, or ultrasparc) you provide, please check the configure script
for a complete list of supported models.

@item --enable-target-optspace
Specify that target
libraries should be optimized for code space instead of code speed.
This is the default for the m32r platform.

@item --disable-cpp
Specify that a user visible @command{cpp} program should not be installed.

@item --with-cpp-install-dir=@var{dirname}
Specify that the user visible @command{cpp} program should be installed
in @file{@var{prefix}/@var{dirname}/cpp}, in addition to @var{bindir}.

@item --enable-maintainer-mode
The build rules that
regenerate the GCC master message catalog @file{gcc.pot} are normally
disabled.  This is because it can only be rebuilt if the complete source
tree is present.  If you have changed the sources and want to rebuild the
catalog, configuring with @option{--enable-maintainer-mode} will enable
this.  Note that you need a recent version of the @code{gettext} tools
to do so.

@item --enable-version-specific-runtime-libs
Specify
that runtime libraries should be installed in the compiler specific
subdirectory (@file{@var{libsubdir}}) rather than the usual places.  In
addition, @samp{libstdc++}'s include files will be installed in
@file{@var{libsubdir}/include/g++} unless you overruled it by using
@option{--with-gxx-include-dir=@var{dirname}}.  Using this option is
particularly useful if you intend to use several versions of GCC in
parallel. This is currently supported by @samp{libf2c} and
@samp{libstdc++}, and is the default for @samp{libobjc} which cannot be
changed in this case.

@item --enable-languages=@var{lang1},@var{lang2},@dots{}
Specify that only a particular subset of compilers and
their runtime libraries should be built.  For a list of valid values for
@var{langN} you can issue the following command in the
@file{gcc} directory of your GCC source tree:@*
@example
grep language= */config-lang.in
@end example
Currently, you can use any of the following:
@code{ada}, @code{c}, @code{c++}, @code{f77}, @code{java}, @code{objc}.
@code{CHILL} is not currently maintained, and will almost
certainly fail to compile.  Building the Ada compiler has special
requirements, see below.@*
If you do not pass this flag, all languages available in the @file{gcc}
sub-tree will be configured.  Re-defining @code{LANGUAGES} when calling
@samp{make bootstrap} @strong{does not} work anymore, as those
language sub-directories might not have been configured!

@item --disable-libgcj
Specify that the run-time libraries
used by GCJ should not be built.  This is useful in case you intend
to use GCJ with some other run-time, or you're going to install it
separately, or it just happens not to build on your particular
machine.  In general, if the Java front end is enabled, the GCJ
libraries will be enabled too, unless they're known to not work on
the target platform.  If GCJ is enabled but @samp{libgcj} isn't built, you
may need to port it; in this case, before modifying the top-level
@file{configure.in} so that @samp{libgcj} is enabled by default on this platform,
you may use @option{--enable-libgcj} to override the default.

@item --with-dwarf2
Specify that the compiler should
use DWARF 2 debugging information as the default.

@item --enable-win32-registry
@itemx --enable-win32-registry=@var{key}
@itemx --disable-win32-registry
The @option{--enable-win32-registry} option enables Windows-hosted GCC
to look up installations paths in the registry using the following key:

@smallexample
@code{HKEY_LOCAL_MACHINE\SOFTWARE\Free Software Foundation\@var{key}}
@end smallexample

@var{key} defaults to GCC version number, and can be overridden by the
@option{--enable-win32-registry=@var{key}} option. Vendors and distributors
who use custom installers are encouraged to provide a different key,
perhaps one comprised of vendor name and GCC version number, to
avoid conflict with existing installations.  This feature is enabled
by default, and can be disabled by @option{--disable-win32-registry}
option.  This option has no effect on the other hosts.

@item --nfp
Specify that the machine does not have a floating point unit.  This
option only applies to @samp{m68k-sun-sunos@var{n}} and
@samp{m68k-isi-bsd}.  On any other system, @option{--nfp} has no effect.

@item --enable-checking
@itemx --enable-checking=@var{list}
When you specify this option, the compiler is built to perform checking
of tree node types when referencing fields of that node, and some other
internal consistency checks.  This does not change the generated code,
but adds error checking within the compiler.  This will slow down the
compiler and may only work properly if you are building the compiler
with GCC@.  This is on by default when building from CVS or snapshots,
but off for releases.  More control over the checks may be had by
specifying @var{list}; the categories of checks available are
@samp{misc}, @samp{tree}, @samp{gc}, @samp{rtl} and @samp{gcac}.  The
default when @var{list} is not specified is @samp{misc,tree,gc}; the
checks @samp{rtl} and @samp{gcac} are very expensive.

@item --enable-nls
@itemx --disable-nls
The @option{--enable-nls} option enables Native Language Support (NLS),
which lets GCC output diagnostics in languages other than American
English.  Native Language Support is enabled by default if not doing a
canadian cross build.  The @option{--disable-nls} option disables NLS@.

@item --with-included-gettext
If NLS is enabled, the @option{--with-included-gettext} option causes the build
procedure to prefer its copy of GNU @command{gettext}.

@item --with-catgets
If NLS is enabled, and if the host lacks @code{gettext} but has the
inferior @code{catgets} interface, the GCC build procedure normally
ignores @code{catgets} and instead uses GCC's copy of the GNU
@code{gettext} library.  The @option{--with-catgets} option causes the
build procedure to use the host's @code{catgets} in this situation.

@item --with-system-zlib
Use installed zlib rather than that included with GCC@.  This option
only applies if the Java front end is being built.
@end table

Some options which only apply to building cross compilers:
@table @code
@item --with-headers=@var{dir}
Specifies a directory
which has target include files.
@emph{This options is required} when building a cross
compiler, if @file{@var{prefix}/@var{target}/sys-include} doesn't pre-exist.
These include files will be copied into the @file{gcc} install directory.
Fixincludes will be run on these files to make them compatible with
GCC.
@item --with-libs=``@var{dir1} @var{dir2} @dots{} @var{dirN}''
Specifies a list of directories which contain the target runtime
libraries.  These libraries will be copied into the @file{gcc} install
directory.
@item --with-newlib
Specifies that @samp{newlib} is
being used as the target C library.  This causes @code{__eprintf} to be
omitted from @file{libgcc.a} on the assumption that it will be provided by
@samp{newlib}.
@end table

Note that each @option{--enable} option has a corresponding
@option{--disable} option and that each @option{--with} option has a
corresponding @option{--without} option.

@html
<hr>
<p>
@end html
@ifhtml
@uref{./index.html,,Return to the GCC Installation page}
@end ifhtml
@end ifset

@c ***Building****************************************************************
@ifnothtml
@comment node-name,     next,          previous, up
@node    Building, Testing, Configuration, Installing GCC
@end ifnothtml
@ifset buildhtml
@html
<h1 align="center">Installing GCC: Building</h1>
@end html
@ifnothtml
@chapter Building
@end ifnothtml
@cindex Installing GCC: Building

Now that GCC is configured, you are ready to build the compiler and
runtime libraries.

We @strong{highly} recommend that GCC be built using GNU make;
other versions may work, then again they might not.  
GNU make is required for compiling GNAT, the Ada compiler.

(For example, many broken versions of make will fail if you use the
recommended setup where @var{objdir} is different from @var{srcdir}.
Other broken versions may recompile parts of the compiler when
installing the compiler.)

Some commands executed when making the compiler may fail (return a
nonzero status) and be ignored by @code{make}.  These failures, which
are often due to files that were not found, are expected, and can safely
be ignored.

It is normal to have compiler warnings when compiling certain files.
Unless you are a GCC developer, you can generally ignore these warnings
unless they cause compilation to fail.

On certain old systems, defining certain environment variables such as
@env{CC} can interfere with the functioning of @command{make}.

If you encounter seemingly strange errors when trying to build the
compiler in a directory other than the source directory, it could be
because you have previously configured the compiler in the source
directory.  Make sure you have done all the necessary preparations.

If you build GCC on a BSD system using a directory stored in an old System
V file system, problems may occur in running @code{fixincludes} if the
System V file system doesn't support symbolic links.  These problems
result in a failure to fix the declaration of @code{size_t} in
@file{sys/types.h}.  If you find that @code{size_t} is a signed type and
that type mismatches occur, this could be the cause.

The solution is not to use such a directory for building GCC@.

When building from CVS or snapshots, or if you modify parser sources,
you need the Bison parser generator installed.  Any version 1.25 or
later should work; older versions may also work.  If you do not modify
parser sources, releases contain the Bison-generated files and you do
not need Bison installed to build them.

When building from CVS or snapshots, or if you modify Texinfo
documentation, you need version 4.0 or later of Texinfo installed if you
want Info documentation to be regenerated.  Releases contain Info
documentation pre-built for the unmodified documentation in the release.

@section Building a native compiler

For a native build issue the command @samp{make bootstrap}.  This
will build the entire GCC system, which includes the following steps:

@itemize @bullet
@item
Build host tools necessary to build the compiler such as texinfo, bison,
gperf.

@item
Build target tools for use by the compiler such as binutils (bfd,
binutils, gas, gprof, ld, and opcodes)
if they have been individually linked 
or moved into the top level GCC source tree before configuring.

@item
Perform a 3-stage bootstrap of the compiler.

@item
Perform a comparison test of the stage2 and stage3 compilers.

@item
Build runtime libraries using the stage3 compiler from the previous step.

@end itemize

If you are short on disk space you might consider @samp{make
bootstrap-lean} instead.  This is identical to @samp{make
bootstrap} except that object files from the stage1 and
stage2 of the 3-stage bootstrap of the compiler are deleted as
soon as they are no longer needed.


If you want to save additional space during the bootstrap and in
the final installation as well, you can build the compiler binaries
without debugging information with @samp{make CFLAGS='-O' LIBCFLAGS='-g
-O2' LIBCXXFLAGS='-g -O2 -fno-implicit-templates' bootstrap}.  This will save
roughly 40% of disk space both for the bootstrap and the final installation.
(Libraries will still contain debugging information.)

If you wish to use non-default GCC flags when compiling the stage2 and
stage3 compilers, set @code{BOOT_CFLAGS} on the command line when doing
@samp{make bootstrap}.  Non-default optimization flags are less well
tested here than the default of @samp{-g -O2}, but should still work.
In a few cases, you may find that you need to specify special flags such
as @option{-msoft-float} here to complete the bootstrap; or, if the
native compiler miscompiles the stage1 compiler, you may need to work
around this, by choosing @code{BOOT_CFLAGS} to avoid the parts of the
stage1 compiler that were miscompiled, or by using @samp{make
bootstrap4} to increase the number of stages of bootstrap.

If you used the flag @option{--enable-languages=@dots{}} to restrict
the compilers to be built, only those you've actually enabled will be
built.  This will of course only build those runtime libraries, for
which the particular compiler has been built.  Please note,
that re-defining @env{LANGUAGES} when calling @samp{make bootstrap}
@strong{does not} work anymore!

If the comparison of stage2 and stage3 fails, this normally indicates
that the stage2 compiler has compiled GCC incorrectly, and is therefore
a potentially serious bug which you should investigate and report.  (On
a few systems, meaningful comparison of object files is impossible; they
always appear ``different''.  If you encounter this problem, you will
need to disable comparison in the @file{Makefile}.)

@section Building a cross compiler

We recommend reading the
@uref{http://www.objsw.com/CrossGCC/,,crossgcc FAQ}
for information about building cross compilers.

When building a cross compiler, it is not generally possible to do a
3-stage bootstrap of the compiler.  This makes for an interesting problem
as parts of GCC can only be built with GCC@.

To build a cross compiler, we first recommend building and installing a
native compiler.  You can then use the native GCC compiler to build the
cross compiler.

Assuming you have already installed a native copy of GCC and configured
your cross compiler, issue the command @command{make}, which performs the
following steps:

@itemize @bullet
@item
Build host tools necessary to build the compiler such as texinfo, bison,
gperf.

@item
Build target tools for use by the compiler such as binutils (bfd,
binutils, gas, gprof, ld, and opcodes)
if they have been individually linked or moved into the top level GCC source
tree before configuring.

@item
Build the compiler (single stage only).

@item
Build runtime libraries using the compiler from the previous step.
@end itemize

Note that if an error occurs in any step the make process will exit.

@section Building in parallel

If you have a multiprocessor system you can use @samp{make bootstrap
MAKE="make -j 2" -j 2} or just @samp{make -j 2 bootstrap}
for GNU Make 3.79 and above instead of just @samp{make bootstrap}
when building GCC@.  You can use a bigger number instead of two if
you like.  In most cases, it won't help to use a number bigger than
the number of processors in your machine.

@section Building the Ada compiler

In order to build GNAT, the Ada compiler, you need a working GNAT
compiler, since the Ada front end is written in Ada (with some
GNAT-specific extensions), and GNU make.

However, you do not need a full installation of GNAT, just the GNAT
binary @file{gnat1}, a copy of @file{gnatbind}, and a compiler driver
which can deal with Ada input (by invoking the @file{gnat1} binary).
You can specify this compiler driver by setting the @env{ADAC}
environment variable at the configure step.  @command{configure} can
detect the driver automatically if it has got a common name such as
@command{gcc} or @command{gnatgcc}.  Of course, you still need a working
C compiler (the compiler driver can be different or not).

Additional build tools (such as @command{gnatmake}) or a working GNAT
run-time library installation are usually @emph{not} required.  However,
if you want to boostrap the compiler using a minimal version of GNAT,
you have to issue the following commands before invoking @samp{make
boostrap} (this assumes that you start with an unmodified and consistent
source distribution):

@example
    cd @var{srcdir}/gcc/ada
    touch treeprs.ads [es]info.h nmake.ad[bs]
@end example

At the moment, the GNAT library and several tools for GNAT are not built
by @samp{make bootstrap}.  You have to invoke 
@samp{make gnatlib_and_tools} in the @file{@var{objdir}/gcc}
subdirectory before proceeding with the next steps.

For example, you can build a native Ada compiler by issuing the
following commands (assuming @command{make} is GNU make):

@example
    cd @var{objdir}
    @var{srcdir}/configure --enable-languages=c,ada 
    cd @var{srcdir}/gcc/ada
    touch treeprs.ads [es]info.h nmake.ad[bs]
    cd @var{objdir}    
    make bootstrap
    cd gcc
    make gnatlib_and_tools
    cd ..
@end example

Currently, when compiling the Ada front end, you cannot use the parallel
build feature described in the previous section.

@html
<hr>
<p>
@end html
@ifhtml
@uref{./index.html,,Return to the GCC Installation page}
@end ifhtml
@end ifset

@c ***Testing*****************************************************************
@ifnothtml
@comment node-name,     next,          previous, up
@node    Testing, Final install, Building, Installing GCC
@end ifnothtml
@ifset testhtml
@html
<h1 align="center">Installing GCC: Testing</h1>
@end html
@ifnothtml
@chapter Installing GCC: Testing
@end ifnothtml
@cindex Testing
@cindex Installing GCC: Testing
@cindex Testsuite

Before you install GCC, you might wish to run the testsuite.  This
step is optional and may require you to download additional software.

First, you must have @uref{download.html,,downloaded the testsuites}.
The full distribution contains testsuites; only if you downloaded the
``core'' compiler plus any front ends, you do not have the testsuites.

Second, you must have a @uref{http://www.gnu.org/software/dejagnu/,,current version of DejaGnu} installed;
dejagnu 1.3 is not sufficient.

Now you may need specific preparations:

@itemize @bullet

@item
The following environment variables may need to be set appropriately, as in
the following example (which assumes that DejaGnu has been installed
under @file{/usr/local}):

@example
     TCL_LIBRARY = /usr/local/share/tcl8.0
     DEJAGNULIBS = /usr/local/share/dejagnu
@end example

On systems such as Cygwin, these paths are required to be actual
paths, not mounts or links; presumably this is due to some lack of
portability in the DejaGnu code.

If the directories where @command{runtest} and @command{expect} were
installed are in the @env{PATH}, it should not be necessary to set these
environment variables.

@end itemize

Finally, you can run the testsuite (which may take a long time):
@example
     cd @var{objdir}; make -k check
@end example

The testing process will try to test as many components in the GCC
distribution as possible, including the C, C++, Objective-C and Fortran
compilers as well as the C++ and Java runtime libraries.

@section How can I run the test suite on selected tests?

As a first possibility to cut down the number of tests that are run it is
possible to use @samp{make check-gcc} or @samp{make check-g++}
in the @file{gcc} subdirectory of the object directory.  To further cut down the
tests the following is possible:

@example
    make check-gcc RUNTESTFLAGS="execute.exp @var{other-options}"
@end example

This will run all @command{gcc} execute tests in the testsuite.

@example
    make check-g++ RUNTESTFLAGS="old-deja.exp=9805* @var{other-options}"
@end example

This will run the @command{g++} ``old-deja'' tests in the testsuite where the filename
matches @samp{9805*}.

The @file{*.exp} files are located in the testsuite directories of the GCC
source, the most important ones being @file{compile.exp},
@file{execute.exp}, @file{dg.exp} and @file{old-deja.exp}.
To get a list of the possible @file{*.exp} files, pipe the
output of @samp{make check} into a file and look at the
@samp{Running @dots{}  .exp} lines.

@section How to interpret test results

After the testsuite has run you'll find various @file{*.sum} and @file{*.log}
files in the testsuite subdirectories.  The @file{*.log} files contain a
detailed log of the compiler invocations and the corresponding
results, the @file{*.sum} files summarize the results.  These summaries list
all the tests that have been run with a corresponding status code:

@itemize @bullet
@item
PASS: the test passed as expected
@item
XPASS: the test unexpectedly passed
@item
FAIL: the test unexpectedly failed
@item
XFAIL: the test failed as expected
@item
UNSUPPORTED: the test is not supported on this platform
@item
ERROR: the testsuite detected an error
@item
WARNING: the testsuite detected a possible problem
@end itemize

It is normal for some tests to report unexpected failures.  At the
current time our testing harness does not allow fine grained control
over whether or not a test is expected to fail.  We expect to fix this
problem in future releases.


@section Submitting test results

If you want to report the results to the GCC project, use the
@file{contrib/test_summary} shell script.  Start it in the @var{objdir} with

@example
    @var{srcdir}/contrib/test_summary -p your_commentary.txt \
        -m gcc-testresults@@gcc.gnu.org |sh
@end example

This script uses the @command{Mail} program to send the results, so
make sure it is in your @env{PATH}.  The file @file{your_commentary.txt} is
prepended to the testsuite summary and should contain any special
remarks you have on your results or your build environment.  Please
do not edit the testsuite result block or the subject line, as these
messages are automatically parsed and presented at the
@uref{http://gcc.gnu.org/testresults/,,GCC testresults} web
page.  Here you can also gather information on how specific tests
behave on different platforms and compare them with your results.  A
few failing testcases are possible even on released versions and you
should look here first if you think your results are unreasonable.

@end ifset

@c ***Final install***********************************************************
@ifnothtml
@comment node-name,     next,          previous, up
@node    Final install, , Testing, Installing GCC
@end ifnothtml
@ifset finalinstallhtml
@html
<h1 align="center">Installing GCC: Final installation</h1>
@end html
@ifnothtml
@chapter Installing GCC: Final installation
@end ifnothtml

Now that GCC has been built (and optionally tested), you can install it with
@example
cd @var{objdir}; make install
@end example

That step completes the installation of GCC; user level binaries can
be found in @file{@var{prefix}/bin} where @var{prefix} is the value you
specified with the @option{--prefix} to configure (or @file{/usr/local}
by default).  (If you specified @option{--bindir}, that directory will
be used instead; otherwise, if you specified @option{--exec-prefix},
@file{@var{exec-prefix}/bin} will be used.)  Headers for the C++ and
Java libraries are installed in @file{@var{prefix}/include}; libraries
in @file{@var{libdir}} (normally @file{@var{prefix}/lib}); internal
parts of the compiler in @file{@var{libdir}/gcc-lib}; documentation in
info format in @file{@var{infodir}} (normally @file{@var{prefix}/info}).

If you built a released version of GCC then if you don't mind, please
quickly review the build status page for
@uref{http://gcc.gnu.org/gcc-3.0/buildstat.html,,3.0} or
@uref{http://gcc.gnu.org/gcc-2.95/buildstat.html,,2.95}.
If your system is not listed, send a note to
@email{gcc@@gcc.gnu.org} indicating
that you successfully built and installed GCC.

Include the output from running @file{@var{srcdir}/config.guess}.  (Do
not send us the @file{config.guess} file itself, just the one-line output from
running it!)  Also specify which version you built.
If the build was for GNU/Linux, also include the distribution name and version
(e.g., Red Hat 7.1 or Debian 2.2.3, available from @file{/etc/issue})
and the version of glibc you used; for RPM-based systems like Red Hat,
Mandrake, and SuSE type @samp{rpm -q glibc} to get the glibc version,
and on systems like Debian and Progeny use @samp{dpkg -l libc6}.

We'd also like to know if the
@ifnothtml
@ref{Specific, host/target specific installation notes}
@end ifnothtml
@ifhtml
@uref{specific.html,,host/target specific installation notes}
@end ifhtml
didn't include your host/target information or if that information is
incomplete or out of date.  Send a note to
@email{gcc@@gcc.gnu.org} telling us how the information should be changed.

If you find a bug, please report it following our
@uref{../bugs.html,,bug reporting guidelines}.

If you want to print the GCC manuals, do @samp{cd @var{objdir}; make
dvi}.  You will need to have @command{texi2dvi} (version at least 4.0)
and @TeX{} installed.  This creates a number of @file{.dvi} files in
subdirectories of @file{@var{objdir}}; these may be converted for
printing with programs such as @command{dvips}.  You can also
@uref{http://www.gnu.org/order/order.html,,buy printed manuals from the
Free Software Foundation}, though such manuals may not be for the most
recent version of GCC@.

@html
<hr>
<p>
@end html
@ifhtml
@uref{./index.html,,Return to the GCC Installation page}
@end ifhtml
@end ifset

@c ***Binaries****************************************************************
@ifnothtml
@comment node-name,     next,          previous, up
@node    Binaries, Specific, Installing GCC, Top
@end ifnothtml
@ifset binarieshtml
@html
<h1 align="center">Installing GCC: Binaries</h1>
@end html
@ifnothtml
@chapter Installing GCC: Binaries
@end ifnothtml
@cindex Binaries
@cindex Installing GCC: Binaries

We are often asked about pre-compiled versions of GCC@.  While we cannot
provide these for all platforms, below you'll find links to binaries for
various platforms where creating them by yourself is not easy due to various
reasons.

Please note that we did not create these binaries, nor do we
support them.  If you have any problems installing them, please
contact their makers.

@itemize
@item
AIX:
@itemize
@item
@uref{http://freeware.bull.net,,Bull's Freeware and Shareware Archive for AIX};

@item
@uref{http://aixpdslib.seas.ucla.edu,,UCLA Software Library for AIX};
@end itemize

@item
DOS---@uref{http://www.delorie.com/djgpp/,,DJGPP};

@item
HP-UX:
@itemize
@item
@uref{http://hpux.cae.wisc.edu/,,HP-UX Porting Center};

@item
@uref{ftp://sunsite.informatik.rwth-aachen.de/pub/packages/gcc_hpux/,,Binaries for HP-UX 11.00 at Aachen University of Technology}.
@end itemize

@item
@uref{http://www.sco.com/skunkware/devtools/index.html#gcc,,SCO
OpenServer/Unixware};

@item
Solaris 2 (SPARC, Intel)---@uref{http://www.sunfreeware.com/,,Sunfreeware};

@item
SGI---@uref{http://freeware.sgi.com/,,SGI Freeware};

@item
Windows 95, 98, and NT:
@itemize
@item
The @uref{http://sources.redhat.com/cygwin/,,Cygwin} project;
@item
@uref{http://www.xraylith.wisc.edu/~khan/software/gnu-win32/,,GNU Win32}
related projects by Mumit Khan.
@end itemize

@item
@uref{ftp://ftp.thewrittenword.com/packages/free/by-name/gcc-2.95.2/,,The
Written Word} offers binaries for Solaris 2.5.1, 2.6, 2.7/SPARC, 2.7/Intel,
IRIX 6.2, 6.5, Digital UNIX 4.0D, HP-UX 10.20, and HP-UX 11.00.

@item
Hitachi H8/300[HS]---@uref{http://h8300-hms.sourceforge.net/,,GNU
Development Tools for the Hitachi H8/300[HS] Series}

@end itemize

In addition to those specific offerings, you can get a binary
distribution CD-ROM from the
@uref{http://www.fsf.org/order/order.html,,Free Software Foundation}.
It contains binaries for a number of platforms, and
includes not only GCC, but other stuff as well.  The current CD does
not contain the latest version of GCC, but it should allow
bootstrapping the compiler.  An updated version of that disk is in the
works.

@html
<hr>
<p>
@end html
@ifhtml
@uref{./index.html,,Return to the GCC Installation page}
@end ifhtml
@end ifset

@c ***Specific****************************************************************
@ifnothtml
@comment node-name,     next,          previous, up
@node    Specific, Concept Index, Binaries, Top
@end ifnothtml
@ifset specifichtml
@html
<h1 align="center">Host/target specific installation notes for GCC</h1>
@end html
@ifnothtml
@chapter Host/target specific installation notes for GCC
@end ifnothtml
@cindex Specific
@cindex Specific installation notes
@cindex Target specific installation
@cindex Host specific installation
@cindex Target specific installation notes

Please read this document carefully @emph{before} installing the
GNU Compiler Collection on your machine.

Lists of successful builds for released versions of GCC are
available at our web pages for
@uref{http://gcc.gnu.org/gcc-3.0/buildstat.html,,3.0}
and
@uref{http://gcc.gnu.org/gcc-2.95/buildstat.html,,2.95}.
These lists are updated as new information becomes available.

@ifhtml
@itemize
@item
@uref{#1750a-*-*,,1750a-*-*}
@item
@uref{#a29k,,a29k}
@item
@uref{#a29k-*-bsd,,a29k-*-bsd}
@item
@uref{#alpha*-*-*,,alpha*-*-*}
@item
@uref{#alpha*-dec-osf*,,alpha*-dec-osf*}
@item
@uref{#alphaev5-cray-unicosmk*,,alphaev5-cray-unicosmk*}
@item
@uref{#arc-*-elf,,arc-*-elf}
@item
@uref{#arm-*-aout,,arm-*-aout}
@item
@uref{#arm-*-elf,,arm-*-elf}
@item
@uref{#arm*-*-linux-gnu,,arm*-*-linux-gnu}
@item
@uref{#arm-*-riscix,,arm-*-riscix}
@item
@uref{#avr,,avr}
@item
@uref{#c4x,,c4x}
@item
@uref{#dos,,DOS}
@item
@uref{#dsp16xx,,dsp16xx}
@item
@uref{#elxsi-elxsi-bsd,,elxsi-elxsi-bsd}
@item
@uref{#*-*-freebsd*,,*-*-freebsd*}
@item
@uref{#h8300-hms,,h8300-hms}
@item
@uref{#hppa*-hp-hpux*,,hppa*-hp-hpux*}
@item
@uref{#hppa*-hp-hpux9,,hppa*-hp-hpux9}
@item
@uref{#hppa*-hp-hpux10,,hppa*-hp-hpux10}
@item
@uref{#hppa*-hp-hpux11,,hppa*-hp-hpux11}
@item
@uref{#i370-*-*,,i370-*-*}
@item
@uref{#*-*-linux-gnu,,*-*-linux-gnu}
@item
@uref{#ix86-*-linux*oldld,,i?86-*-linux*oldld}
@item
@uref{#ix86-*-linux*aout,,i?86-*-linux*aout}
@item
@uref{#ix86-*-linux*,,i?86-*-linux*}
@item
@uref{#ix86-*-sco,,i?86-*-sco}
@item
@uref{#ix86-*-sco3.2v4,,i?86-*-sco3.2v4}
@item
@uref{#ix86-*-sco3.2v5*,,i?86-*-sco3.2v5*}
@item
@uref{#ix86-*-udk,,i?86-*-udk}
@item
@uref{#ix86-*-isc,,i?86-*-isc}
@item
@uref{#ix86-*-esix,,i?86-*-esix}
@item
@uref{#ix86-ibm-aix,,i?86-ibm-aix}
@item
@uref{#ix86-sequent-bsd,,i?86-sequent-bsd}
@item
@uref{#ix86-sequent-ptx1*,,i?86-sequent-ptx1*, i?86-sequent-ptx2*}
@item
@uref{#ix86-*-sysv3*,,i?86-*-sysv3*}
@item
@uref{#i860-intel-osf*,,i860-intel-osf*}
@item
@uref{#ia64-*-linux,,ia64-*-linux}
@item
@uref{#*-lynx-lynxos,,*-lynx-lynxos}
@item
@uref{#*-ibm-aix*,,*-ibm-aix*}
@item
@uref{#m32r-*-elf,,m32r-*-elf}
@item
@uref{#m68000-hp-bsd,,m68000-hp-bsd}
@item
@uref{#m6811-elf,,m6811-elf}
@item
@uref{#m6812-elf,,m6812-elf}
@item
@uref{#m68k-altos,,m68k-altos}
@item
@uref{#m68k-apple-aux,,m68k-apple-aux}
@item
@uref{#m68k-att-sysv,,m68k-att-sysv}
@item
@uref{#m68k-bull-sysv,,m68k-bull-sysv}
@item
@uref{#m68k-crds-unox,,m68k-crds-unox}
@item
@uref{#m68k-hp-hpux,,m68k-hp-hpux}
@item
@uref{#m68k-*-nextstep*,,m68k-*-nextstep*}
@item
@uref{#m68k-ncr-*,,m68k-ncr-*}
@item
@uref{#m68k-sun,,m68k-sun}
@item
@uref{#m68k-sun-sunos4.1.1,,m68k-sun-sunos4.1.1}
@item
@uref{#m88k-*-svr3,,m88k-*-svr3}
@item
@uref{#m88k-*-dgux,,m88k-*-dgux}
@item
@uref{#m88k-tektronix-sysv3,,m88k-tektronix-sysv3}
@item
@uref{#mips-*-*,,mips-*-*}
@item
@uref{#mips-dec-*,,mips-dec-*}
@item
@uref{#mips-mips-bsd,,mips-mips-bsd}
@item
@uref{#mips-mips-riscos*,,mips-mips-riscos*}
@item
@uref{#mips-sgi-irix4,,mips-sgi-irix4}
@item
@uref{#mips-sgi-irix5,,mips-sgi-irix5}
@item
@uref{#mips-sgi-irix6,,mips-sgi-irix6}
@item
@uref{#mips-sony-sysv,,mips-sony-sysv}
@item
@uref{#ns32k-encore,,ns32k-encore}
@item
@uref{#ns32k-*-genix,,ns32k-*-genix}
@item
@uref{#ns32k-sequent,,ns32k-sequent}
@item
@uref{#ns32k-utek,,ns32k-utek}
@item
@uref{#powerpc*-*-*,,powerpc*-*-*, powerpc-*-sysv4}
@item
@uref{#powerpc-*-darwin*,,powerpc-*-darwin*}
@item
@uref{#powerpc-*-elf,,powerpc-*-elf, powerpc-*-sysv4}
@item
@uref{#powerpc-*-linux-gnu*,,powerpc-*-linux-gnu*}
@item
@uref{#powerpc-*-netbsd*,,powerpc-*-netbsd*}
@item
@uref{#powerpc-*-eabiaix,,powerpc-*-eabiaix}
@item
@uref{#powerpc-*-eabisim,,powerpc-*-eabisim}
@item
@uref{#powerpc-*-eabi,,powerpc-*-eabi}
@item
@uref{#powerpcle-*-elf,,powerpcle-*-elf, powerpcle-*-sysv4}
@item
@uref{#powerpcle-*-eabisim,,powerpcle-*-eabisim}
@item
@uref{#powerpcle-*-eabi,,powerpcle-*-eabi}
@item
@uref{#powerpcle-*-winnt,,powerpcle-*-winnt, powerpcle-*-pe}
@item
@uref{#romp-*-aos,,romp-*-aos, romp-*-mach}
@item
@uref{#s390-*-linux*}
@item
@uref{#s390x-*-linux*}
@item
@uref{#*-*-solaris2*,,*-*-solaris2*}
@item
@uref{#sparc-sun-solaris2*,,sparc-sun-solaris2*}
@item
@uref{#sparc-sun-solaris2.7,,sparc-sun-solaris2.7}
@item
@uref{#*-*-solaris2.8,,*-*-solaris2.8}
@item
@uref{#sparc-sun-sunos4*,,sparc-sun-sunos4*}
@item
@uref{#sparc-unknown-linux-gnulibc1,,sparc-unknown-linux-gnulibc1}
@item
@uref{#sparc-*-linux*,,sparc-*-linux*}
@item
@uref{#sparc64-*-*,,sparc64-*-*}
@item
@uref{#*-*-sysv*,,*-*-sysv*}
@item
@uref{#vax-dec-ultrix,,vax-dec-ultrix}
@item
@uref{#we32k-*-*,,we32k-*-*}
@item
@uref{#windows,,Microsoft Windows}
@item
@uref{#os2,,OS/2}
@item
@uref{#older,,Older systems}
@end itemize

@itemize
@item
@uref{#elf_targets,,all ELF targets} (SVR4, Solaris 2, etc.)
@end itemize
@end ifhtml


@html
<!-- -------- host/target specific issues start here ---------------- -->
<hr>
@end html
@heading @anchor{1750a-*-*}1750a-*-*
MIL-STD-1750A processors.

The MIL-STD-1750A cross configuration produces output for
@code{as1750}, an assembler/linker available under the GNU General Public
License for the 1750A@.  @code{as1750} can be obtained at
@uref{ftp://ftp.fta-berlin.de/pub/crossgcc/1750gals/}.
A similarly licensed simulator for
the 1750A is available from same address.

You should ignore a fatal error during the building of @samp{libgcc}
(@samp{libgcc} is not yet implemented for the 1750A@.)

The @code{as1750} assembler requires the file @file{ms1750.inc}, which is
found in the directory @file{gcc/config/1750a}.

GCC produced the same sections as the Fairchild F9450 C Compiler,
namely:

@table @code
@item Normal
The program code section.

@item Static
The read/write (RAM) data section.

@item Konst
The read-only (ROM) constants section.

@item Init
Initialization section (code to copy KREL to SREL)@.
@end table

The smallest addressable unit is 16 bits (@code{BITS_PER_UNIT} is 16).  This
means that type @code{char} is represented with a 16-bit word per character.
The 1750A's ``Load/Store Upper/Lower Byte'' instructions are not used by
GCC@.

@html
</p>
<hr>
@end html
@heading @anchor{a29k}a29k
AMD Am29k-family processors.  These are normally used in embedded
applications.  There are no standard Unix configurations.
This configuration
corresponds to AMD's standard calling sequence and binary interface
and is compatible with other 29k tools.

You may need to make a variant of the file @file{a29k.h} for your
particular configuration.

@html
</p>
<hr>
@end html
@heading @anchor{a29k-*-bsd}a29k-*-bsd
AMD Am29050 used in a system running a variant of BSD Unix.

@html
</p>
<hr>
@end html
@heading @anchor{alpha*-*-*}alpha*-*-*

This section contains general configuration information for all
alpha-based platforms using ELF (in particular, ignore this section for
DEC OSF/1, Digital UNIX and Tru64 UNIX)@.  In addition to reading this
section, please read all other sections that match your target.

We require binutils 2.11.2 or newer.
Previous binutils releases had a number of problems with DWARF 2
debugging information, not the least of which is incorrect linking of
shared libraries.

@html
</p>
<hr>
@end html
@heading @anchor{alpha*-dec-osf*}alpha*-dec-osf*
Systems using processors that implement the DEC Alpha architecture and
are running the DEC/Compaq Unix (DEC OSF/1, Digital UNIX, or Compaq
Tru64 UNIX) operating system, for example the DEC Alpha AXP systems.

In Tru64 UNIX V5.1, Compaq introduced a new assembler that does not
currently (2001-06-13) work with @command{mips-tfile}.  As a workaround,
we need to use the old assembler, invoked via the barely documented
@option{-oldas} option.  To bootstrap GCC, you either need to use the
Compaq C Compiler:

@example
   % CC=cc @var{srcdir}/configure [@var{options}] [@var{target}]
@end example

or you can use a copy of GCC 2.95.3 or higher built on Tru64 UNIX V4.0:

@example
   % CC=gcc -Wa,-oldas @var{srcdir}/configure [@var{options}] [@var{target}]
@end example

As of GNU binutils 2.11.2, neither GNU @command{as} nor GNU @command{ld}
are supported on Tru64 UNIX, so you must not configure GCC with
@option{--with-gnu-as} or @option{--with-gnu-ld}.

The @option{--enable-threads} options isn't supported yet.  A patch is
in preparation for a future release.  The Java runtime library has been
reported to work on Tru64 UNIX V4.0F, V5.0, and V5.1, so you may try
@option{--enable-libgcj} and report your results.

GCC writes a @samp{.verstamp} directive to the assembler output file
unless it is built as a cross-compiler.  It gets the version to use from
the system header file @file{/usr/include/stamp.h}.  If you install a
new version of DEC Unix, you should rebuild GCC to pick up the new version
stamp.

Note that since the Alpha is a 64-bit architecture, cross-compilers from
32-bit machines will not generate code as efficient as that generated
when the compiler is running on a 64-bit machine because many
optimizations that depend on being able to represent a word on the
target in an integral value on the host cannot be performed.  Building
cross-compilers on the Alpha for 32-bit machines has only been tested in
a few cases and may not work properly.

@code{make compare} may fail on old versions of DEC Unix unless you add
@option{-save-temps} to @code{CFLAGS}.  On these systems, the name of the
assembler input file is stored in the object file, and that makes
comparison fail if it differs between the @code{stage1} and
@code{stage2} compilations.  The option @option{-save-temps} forces a
fixed name to be used for the assembler input file, instead of a
randomly chosen name in @file{/tmp}.  Do not add @option{-save-temps}
unless the comparisons fail without that option.  If you add
@option{-save-temps}, you will have to manually delete the @samp{.i} and
@samp{.s} files after each series of compilations.

GCC now supports both the native (ECOFF) debugging format used by DBX
and GDB and an encapsulated STABS format for use only with GDB@.  See the
discussion of the @option{--with-stabs} option of @file{configure} above
for more information on these formats and how to select them.

There is a bug in DEC's assembler that produces incorrect line numbers
for ECOFF format when the @samp{.align} directive is used.  To work
around this problem, GCC will not emit such alignment directives
while writing ECOFF format debugging information even if optimization is
being performed.  Unfortunately, this has the very undesirable
side-effect that code addresses when @option{-O} is specified are
different depending on whether or not @option{-g} is also specified.

To avoid this behavior, specify @option{-gstabs+} and use GDB instead of
DBX@.  DEC is now aware of this problem with the assembler and hopes to
provide a fix shortly.

@html
</p>
<hr>
@end html
@heading @anchor{alphaev5-cray-unicosmk*}alphaev5-cray-unicosmk*
Cray T3E systems running Unicos/Mk.

This port is incomplete and has many known bugs.  We hope to improve the
support for this target soon.  Currently, only the C front end is supported,
and it is not possible to build parallel applications.  Cray modules are not
supported; in particular, Craylibs are assumed to be in
@file{/opt/ctl/craylibs/craylibs}.

You absolutely @strong{must} use GNU make on this platform.  Also, you
need to tell GCC where to find the assembler and the linker.  The
simplest way to do so is by providing @option{--with-as} and
@option{--with-ld} to @file{configure}, e.g.@:

@samp{configure --with-as=/opt/ctl/bin/cam --with-ld=/opt/ctl/bin/cld
--enable-languages=c}

The comparison test during @samp{make bootstrap} fails on Unicos/Mk
because the assembler inserts timestamps into object files.  You should
be able to work around this by doing @samp{make all} after getting this
failure.

@html
</p>
<hr>
@end html
@heading @anchor{arc-*-elf}arc-*-elf
Argonaut ARC processor.
This configuration is intended for embedded systems.

@html
</p>
<hr>
@end html
@heading @anchor{arm-*-aout}arm-*-aout
Advanced RISC Machines ARM-family processors.  These are often used in
embedded applications.  There are no standard Unix configurations.
This configuration corresponds to the basic instruction sequences and will
produce @file{a.out} format object modules.

You may need to make a variant of the file @file{arm.h} for your particular
configuration.

@html
</p>
<hr>
@end html
@heading @anchor{arm-*-elf}arm-*-elf
This configuration is intended for embedded systems.

@html
</p>
<hr>
@end html
@heading @anchor{arm*-*-linux-gnu}arm*-*-linux-gnu

We require GNU binutils 2.10 or newer.

@html
</p>
<hr>
@end html
@heading @anchor{arm-*-riscix}arm-*-riscix
The ARM2 or ARM3 processor running RISC iX, Acorn's port of BSD Unix.
If you are running a version of RISC iX prior to 1.2 then you must
specify the version number during configuration.  Note that the
assembler shipped with RISC iX does not support stabs debugging
information; a new version of the assembler, with stabs support
included, is now available from Acorn and via ftp
@uref{ftp://ftp.acorn.com/pub/riscix/as+xterm.tar.Z}.  To enable stabs
debugging, pass @option{--with-gnu-as} to configure.

You will need to install GNU @command{sed} before you can run configure.

@html
</p>
<hr>
@end html
@heading @anchor{avr}avr

ATMEL AVR-family micro controllers.  These are used in embedded
applications.  There are no standard Unix configurations.
@ifnothtml
@xref{AVR Options,, AVR Options, gcc, Using and Porting the GNU Compiler
Collection (GCC)},
@end ifnothtml
@ifhtml
See ``AVR Options'' in the main manual
@end ifhtml
for the list of supported MCU types.

Use @samp{configure --target=avr --enable-languages="c"} to configure GCC@.

Further installation notes and other useful information about AVR tools
can also be obtained from:

@itemize @bullet
@item
@uref{http://home.overta.ru/users/denisc,,http://home.overta.ru/users/denisc}
@item
@uref{http://www.itnet.pl/amelektr/avr,,http://www.itnet.pl/amelektr/avr}
@end itemize

We @emph{strongly} recommend using binutils 2.11 or newer.

The following error:
@example
  Error: register required
@end example

indicates that you should upgrade to a newer version of the binutils.

@html
</p>
<hr>
@end html
@heading @anchor{c4x}c4x

Texas Instruments TMS320C3x and TMS320C4x Floating Point Digital Signal
Processors.  These are used in embedded applications.  There are no
standard Unix configurations.
@ifnothtml
@xref{TMS320C3x/C4x Options,, TMS320C3x/C4x Options, gcc, Using and
Porting the GNU Compiler Collection (GCC)},
@end ifnothtml
@ifhtml
See ``TMS320C3x/C4x Options'' in the main manual
@end ifhtml
for the list of supported MCU types.

GCC can be configured as a cross compiler for both the C3x and C4x
architectures on the same system.  Use @samp{configure --target=c4x
--enable-languages="c,c++"} to configure.


Further installation notes and other useful information about C4x tools
can also be obtained from:

@itemize @bullet
@item
@uref{http://www.elec.canterbury.ac.nz/c4x/,,http://www.elec.canterbury.ac.nz/c4x/}
@end itemize

@html
</p>
<hr>
@end html
@heading @anchor{cris}CRIS

CRIS is the CPU architecture in Axis Communications ETRAX system-on-a-chip
series.  These are used in embedded applications.

@ifnothtml
@xref{CRIS Options,, CRIS Options, gcc, Using and Porting the GNU Compiler
Collection (GCC)},
@end ifnothtml
@ifhtml
See ``CRIS Options'' in the main manual
@end ifhtml
for a list of CRIS-specific options.

There are a few different CRIS targets:
@table @code
@item cris-axis-aout
Old target.  Includes a multilib for the @samp{elinux} a.out-based
target.  No multilibs for newer architecture variants.
@item cris-axis-elf
Mainly for monolithic embedded systems.  Includes a multilib for the
@samp{v10} core used in @samp{ETRAX 100 LX}.
@item cris-axis-linux-gnu
A GNU/Linux port for the CRIS architecture, currently targeting
@samp{ETRAX 100 LX} by default.
@end table

For @code{cris-axis-aout} and @code{cris-axis-elf} you need binutils 2.11
or newer.  For @code{cris-axis-linux-gnu} you need binutils 2.12 or newer.

Pre-packaged tools can be obtained from
@uref{ftp://ftp.axis.com/pub/axis/tools/cris/compiler-kit/}.  More
information about this platform is available at
@uref{http://developer.axis.com/}.

@html
</p>
<hr>
@end html
@heading @anchor{dos}DOS

Please have a look at our @uref{binaries.html,,binaries page}.

You cannot install GCC by itself on MSDOS; it will not compile under
any MSDOS compiler except itself.  You need to get the complete
compilation package DJGPP, which includes binaries as well as sources,
and includes all the necessary compilation tools and libraries.

@html
</p>
<hr>
@end html
@heading @anchor{dsp16xx}dsp16xx
A port to the AT&T DSP1610 family of processors.

@html
</p>
<hr>
@end html
@heading @anchor{*-*-freebsd*}*-*-freebsd*

The version of binutils installed in @file{/usr/bin} is known to work unless
otherwise specified in any per-architecture notes.  However, binutils
2.11 is known to improve overall testsuite results.

For FreeBSD 1, FreeBSD 2 or any mutant a.out versions of FreeBSD 3: All
configuration support and files as shipped with GCC 2.95 are still in
place.  FreeBSD 2.2.7 has been known to bootstrap completely; however,
it is unknown which version of binutils was used (it is assumed that it
was the system copy in @file{/usr/bin}) and C++ EH failures were noted.

For FreeBSD using the ELF file format: DWARF 2 debugging is now the
default for all CPU architectures.  It had been the default on
FreeBSD/alpha since its inception.  You may use @option{-gstabs} instead
of @option{-g}, if you really want the old debugging format.  There are
no known issues with mixing object files and libraries with different
debugging formats.  Otherwise, this release of GCC should now match more
of the configuration used in the stock FreeBSD configuration of GCC.  In
particular, @option{--enable-threads} is now configured by default.
However, as a general user, do not attempt to replace the system
compiler with this release.  Known to bootstrap and check with good
results on FreeBSD 3.0, 3.4, 4.0, 4.2, 4.3 and 5-CURRENT@.

At this time, @option{--enable-threads} is not compatible with
@option{--enable-libgcj} on FreeBSD@.

@html
</p>
<hr>
@end html
@heading @anchor{elxsi-elxsi-bsd}elxsi-elxsi-bsd
The Elxsi's C compiler has known limitations that prevent it from
compiling GCC@.  Please contact @email{mrs@@wrs.com} for more details.

@html
</p>
<hr>
@end html
@heading @anchor{h8300-hms}h8300-hms
Hitachi H8/300 series of processors.

Please have a look at our @uref{binaries.html,,binaries page}.

The calling convention and structure layout has changed in release 2.6.
All code must be recompiled.  The calling convention now passes the
first three arguments in function calls in registers.  Structures are no
longer a multiple of 2 bytes.

@html
</p>
<hr>
@end html
@heading @anchor{hppa*-hp-hpux*}hppa*-hp-hpux*

We @emph{highly} recommend using gas/binutils 2.8 or newer on all hppa
platforms; you may encounter a variety of problems when using the HP
assembler.

Specifically, @option{-g} does not work on HP-UX (since that system
uses a peculiar debugging format which GCC does not know about), unless you
use GAS and GDB and configure GCC with the
@uref{./configure.html#with-gnu-as,,@option{--with-gnu-as}} and
@option{--with-as=@dots{}} options.

If you wish to use pa-risc 2.0 architecture support, you must use either
the HP assembler, gas/binutils 2.11 or a recent
@uref{ftp://sources.redhat.com/pub/binutils/snapshots,,snapshot of gas}.

More specific information to @samp{hppa*-hp-hpux*} targets follows.

@html
</p>
<hr>
@end html
@heading @anchor{hppa*-hp-hpux9}hppa*-hp-hpux9

The HP assembler has major problems on this platform.  We've tried to work
around the worst of the problems.  However, those workarounds may be causing
linker crashes in some circumstances; the workarounds also probably prevent
shared libraries from working.  Use the GNU assembler to avoid these problems.


The configuration scripts for GCC will also trigger a bug in the hpux9
shell.  To avoid this problem set @env{CONFIG_SHELL} to @file{/bin/ksh}
and @env{SHELL} to @file{/bin/ksh} in your environment.


@html
</p>
<hr>
@end html
@heading @anchor{hppa*-hp-hpux10}hppa*-hp-hpux10

For hpux10.20, we @emph{highly} recommend you pick up the latest sed patch
@code{PHCO_19798} from HP@.  HP has two sites which provide patches free of
charge:

@itemize @bullet
@item
@html
<a href="http://us-support.external.hp.com">US, Canada, Asia-Pacific, and
Latin-America</a>
@end html
@ifnothtml
@uref{http://us-support.external.hp.com,,}US, Canada, Asia-Pacific, and
Latin-America
@end ifnothtml
@item
@uref{http://europe-support.external.hp.com,,Europe}
@end itemize

The HP assembler on these systems is much better than the hpux9 assembler,
but still has some problems.  Most notably the assembler inserts timestamps
into each object file it creates, causing the 3-stage comparison test to fail
during a @samp{make bootstrap}.  You should be able to continue by
saying @samp{make all} after getting the failure from @samp{make
bootstrap}.


@html
</p>
<hr>
@end html
@heading @anchor{hppa*-hp-hpux11}hppa*-hp-hpux11

GCC 3.0 supports HP-UX 11.  You must use GNU binutils 2.11 or above on
this platform.

@html
</p>
<hr>
@end html
@heading @anchor{i370-*-*}i370-*-*
This port is very preliminary and has many known bugs.  We hope to
have a higher-quality port for this machine soon.

@html
</p>
<hr>
@end html
@heading @anchor{*-*-linux-gnu}*-*-linux-gnu

If you use glibc 2.2 (or 2.1.9x), GCC 2.95.2 won't install
out-of-the-box.  You'll get compile errors while building @samp{libstdc++}.
The patch @uref{glibc-2.2.patch,,glibc-2.2.patch}, that is to be
applied in the GCC source tree, fixes the compatibility problems.

@html
</p>
@end html

@html
<p>
@end html

Currently Glibc 2.2.3 (and older releases) and GCC 3.0 are out of sync
since the latest exception handling changes for GCC@.  Compiling glibc
with GCC 3.0 will give a binary incompatible glibc and therefore cause
lots of problems and might make your system completly unusable.  This
will definitly need fixes in glibc but might also need fixes in GCC@.  We
strongly advise to wait for glibc 2.2.4 and to read the release notes of
glibc 2.2.4 whether patches for GCC 3.0 are needed.  You can use glibc
2.2.3 with GCC 3.0, just do not try to recompile it.

@html
</p>
<hr>
@end html
@heading @anchor{ix86-*-linux*oldld}i?86-*-linux*oldld
Use this configuration to generate @file{a.out} binaries on Linux-based
GNU systems if you do not have gas/binutils version 2.5.2 or later
installed.  This is an obsolete configuration.

@html
</p>
<hr>
@end html
@heading @anchor{ix86-*-linux*aout}i?86-*-linux*aout
Use this configuration to generate @file{a.out} binaries on Linux-based
GNU systems.  This configuration is being superseded.  You must use
gas/binutils version 2.5.2 or later.

@html
</p>
<hr>
@end html
@heading @anchor{ix86-*-linux*}i?86-*-linux*

You will need binutils 2.9.1.0.15 or newer for exception handling to work.

If you receive Signal 11 errors when building on GNU/Linux, then it is
possible you have a hardware problem.  Further information on this can be
found on @uref{http://www.bitwizard.nl/sig11/,,www.bitwizard.nl}.

@html
</p>
<hr>
@end html
@heading @anchor{ix86-*-sco}i?86-*-sco
Compilation with RCC is recommended.  Also, it may be a good idea to
link with GNU malloc instead of the malloc that comes with the system.

@html
</p>
<hr>
@end html
@heading @anchor{ix86-*-sco3.2v4}i?86-*-sco3.2v4
Use this configuration for SCO release 3.2 version 4.

@html
</p>
<hr>
@end html
@heading @anchor{ix86-*-sco3.2v5*}i?86-*-sco3.2v5*
Use this for the SCO OpenServer Release 5 family of operating systems.

Unlike earlier versions of GCC, the ability to generate COFF with this
target is no longer provided.

Earlier versions of GCC emitted DWARF 1 when generating ELF to allow
the system debugger to be used.  That support was too burdensome to
maintain.  GCC now emits only DWARF 2 for this target.  This means you
may use either the UDK debugger or GDB to debug programs built by this
version of GCC@.

Use of the @option{-march=pentiumpro} flag can result in
unrecognized opcodes when using the native assembler on OS versions before
5.0.6.  (Support for P6 opcodes was added to the native ELF assembler in
that version.)  While it's rather rare to see these emitted by GCC yet,
errors of the basic form:

@example
  /usr/tmp/ccaNlqBc.s:22:unknown instruction: fcomip
  /usr/tmp/ccaNlqBc.s:50:unknown instruction: fucomip
@end example

are symptoms of this problem.  You may work around this by not
building affected files with that flag, by using the GNU assembler, or
by using the assembler provided with the current version of the OS@.
Users of GNU assembler should see the note below for hazards on doing
so.

The native SCO assembler that is provided with the OS at no
charge is normally required.  If, however, you must be able to use
the GNU assembler (perhaps you're compiling code with asms that
require GAS syntax) you may configure this package using the flags
@uref{./configure.html#with-gnu-as,,@option{--with-gnu-as}}.  You must
use a recent version of GNU binutils; versions past 2.9.1 seem to work
well.

In general, the @option{--with-gnu-as} option isn't as well tested
as the native assembler.

Look in @file{gcc/config/i386/sco5.h} (search for ``messy'') for
additional OpenServer-specific flags.

Systems based on OpenServer before 5.0.4 (@samp{uname -X}
will tell you what you're running) require TLS597 from
@uref{ftp://ftp.sco.com/TLS/,,ftp://ftp.sco.com/TLS/}
for C++ constructors and destructors to work right.

The system linker in (at least) 5.0.4 and 5.0.5 will sometimes
do the wrong thing for a construct that GCC will emit for PIC
code.  This can be seen as execution testsuite failures when using
@option{-fPIC} on @file{921215-1.c}, @file{931002-1.c}, @file{nestfunc-1.c}, and @file{gcov-1.c}.
For 5.0.5, an updated linker that will cure this problem is
available.  You must install both
@uref{ftp://ftp.sco.com/Supplements/rs505a/,,ftp://ftp.sco.com/Supplements/rs505a/}
and @uref{ftp://ftp.sco.com/SLS/,,OSS499A}.

The dynamic linker in OpenServer 5.0.5 (earlier versions may show
the same problem) aborts on certain G77-compiled programs.  It's particularly
likely to be triggered by building Fortran code with the @option{-fPIC} flag.
Although it's conceivable that the error could be triggered by other
code, only G77-compiled code has been observed to cause this abort.
If you are getting core dumps immediately upon execution of your
G77 program---and especially if it's compiled with @option{-fPIC}---try applying
@uref{sco_osr5_g77.patch,,@file{sco_osr5_g77.patch}} to your @samp{libf2c} and
rebuilding GCC@.
Affected faults, when analyzed in a debugger, will show a stack
backtrace with a fault occurring in @code{rtld()} and the program
running as @file{/usr/lib/ld.so.1}.  This problem has been reported to SCO
engineering and will hopefully be addressed in later releases.


@html
</p>
<hr>
@end html
@heading @anchor{ix86-*-udk}i?86-*-udk

This target emulates the SCO Universal Development Kit and requires that
package be installed.  (If it is installed, you will have a
@file{/udk/usr/ccs/bin/cc} file present.)  It's very much like the
@samp{i?86-*-unixware7*} target
but is meant to be used when hosting on a system where UDK isn't the
default compiler such as OpenServer 5 or Unixware 2.  This target will
generate binaries that will run on OpenServer, Unixware 2, or Unixware 7,
with the same warnings and caveats as the SCO UDK@.

This target is a little tricky to build because we have to distinguish
it from the native tools (so it gets headers, startups, and libraries
from the right place) while making the tools not think we're actually
building a cross compiler.   The easiest way to do this is with a configure
command like this:

@samp{CC=/udk/usr/ccs/bin/cc @var{/your/path/to}/gcc/configure
--host=i686-pc-udk --target=i686-pc-udk --program-prefix=udk-}

@emph{You should substitute @samp{i686} in the above command with the appropriate
processor for your host.}

After the usual @samp{make bootstrap} and
@samp{make install}, you can then access the UDK-targeted GCC
tools by adding @command{udk-} before the commonly known name.  For
example, to invoke the C compiler, you would use @command{udk-gcc}.
They will coexist peacefully with any native-target GCC tools you may
have installed.


@html
</p>
<hr>
@end html
@heading @anchor{ix86-*-isc}i?86-*-isc
It may be a good idea to link with GNU malloc instead of the malloc that
comes with the system.

In ISC version 4.1, @command{sed} core dumps when building
@file{deduced.h}.  Use the version of @command{sed} from version 4.0.

@html
</p>
<hr>
@end html
@heading @anchor{ix86-*-esix}i?86-*-esix
It may be good idea to link with GNU malloc instead of the malloc that
comes with the system.

@html
</p>
<hr>
@end html
@heading @anchor{ix86-ibm-aix}i?86-ibm-aix
You need to use GAS version 2.1 or later, and LD from
GNU binutils version 2.2 or later.

@html
</p>
<hr>
@end html
@heading @anchor{ix86-sequent-bsd}i?86-sequent-bsd
Go to the Berkeley universe before compiling.

@html
</p>
<hr>
@end html
@heading @anchor{ix86-sequent-ptx1*}i?86-sequent-ptx1*, i?86-sequent-ptx2*
You must install GNU @command{sed} before running @command{configure}.

@html
</p>
<hr>
@end html
@heading @anchor{#ix86-*-sysv3*}i?86-*-sysv3*
The @code{fixproto} shell script may trigger a bug in the system shell.
If you encounter this problem, upgrade your operating system or
use @command{bash} (the GNU shell) to run @code{fixproto}.


@html
</p>
<hr>
@end html
@heading @anchor{i860-intel-osf*}i860-intel-osf*
On the Intel Paragon (an i860 machine), if you are using operating
system version 1.0, you will get warnings or errors about redefinition
of @code{va_arg} when you build GCC@.

If this happens, then you need to link most programs with the library
@file{iclib.a}.  You must also modify @file{stdio.h} as follows: before
the lines

@example
#if     defined(__i860__) && !defined(_VA_LIST)
#include <va_list.h>
@end example

@noindent
insert the line

@example
#if __PGC__
@end example

@noindent
and after the lines

@example
extern int  vprintf(const char *, va_list );
extern int  vsprintf(char *, const char *, va_list );
#endif
@end example

@noindent
insert the line

@example
#endif /* __PGC__ */
@end example

These problems don't exist in operating system version 1.1.

@html
</p>
<hr>
@end html
@heading @anchor{ia64-*-linux}ia64-*-linux
IA-64 processor (also known as IPF, or Itanium Processor Family)
running GNU/Linux.

The toolchain is not completely finished, so requirements will continue
to change.
GCC 3.0.1 and later require glibc 2.2.4.
GCC 3.0.2 requires binutils from 2001-09-05 or later.
GCC 3.0.1 requires binutils 2.11.1 or later.

None of the following versions of GCC has an ABI that is compatible
with any of the other versions in this list, with the exception that
Red Hat 2.96 and Trillian 000171 are compatible with each other:
3.0.2, 3.0.1, 3.0, Red Hat 2.96, and Trillian 000717.
This primarily affects C++ programs and programs that create shared libraries.
Because of these ABI incompatibilities, GCC 3.0.2 is not recommended for
user programs on GNU/Linux systems built using earlier compiler releases.
GCC 3.0.2 is recommended for compiling linux, the kernel.
GCC 3.0.2 is believed to be fully ABI compliant, and hence no more major
ABI changes are expected.

@html
</p>
<hr>
@end html
@heading @anchor{*-lynx-lynxos}*-lynx-lynxos
LynxOS 2.2 and earlier comes with GCC 1.x already installed as
@file{/bin/gcc}.  You should compile with this instead of @file{/bin/cc}.
You can tell GCC to use the GNU assembler and linker, by specifying
@samp{--with-gnu-as --with-gnu-ld} when configuring.  These will produce
COFF format object files and executables;  otherwise GCC will use the
installed tools, which produce @file{a.out} format executables.

@html
</p>
<hr>
<!-- rs6000-ibm-aix*, powerpc-ibm-aix* -->
@end html
@heading @anchor{*-ibm-aix*}*-ibm-aix*

AIX Make frequently has problems with GCC makefiles.  GNU Make 3.76 or
newer is recommended to build on this platform.

Errors involving @code{alloca} when building GCC generally are due
to an incorrect definition of @code{CC} in the Makefile or mixing files
compiled with the native C compiler and GCC@.  During the stage1 phase of
the build, the native AIX compiler @strong{must} be invoked as @command{cc}
(not @command{xlc}).  Once @command{configure} has been informed of
@command{xlc}, one needs to use @samp{make distclean} to remove the
configure cache files and ensure that @env{CC} environment variable
does not provide a definition that will confuse @command{configure}.
If this error occurs during stage2 or later, then the problem most likely
is the version of Make (see above).

Binutils 2.10 does not support AIX 4.3.  Binutils available from the
@uref{http://www-1.ibm.com/servers/aix/products/aixos/linux/,,AIX
Toolbox for Linux: GNU and Open Source tools for AIX};
website does work.  Binutils 2.11 is expected to include AIX 4.3
support.  The GNU Assembler is necessary for @samp{libstdc++} to build.  The
AIX native @command{ld} still is recommended.  The native AIX tools do
interoperate with GCC@.

Linking executables and shared libraries may produce warnings of
duplicate symbols.  The assembly files generated by GCC for AIX always
have included multiple symbol definitions for certain global variable
and function declarations in the original program.  The warnings should
not prevent the linker from producing a correct library or runnable
executable.

GCC's exception handling implementation stores process-specific data in
the shared library which prevents exception handling from working
correctly on AIX in a default installation.  To work around this, the
shared objects need to be loaded in the process private segment to
prevent them from being shared and marked read-only.  This is
accomplished on AIX by installing the shared libraries
(@file{libgcc_s.a} and @file{libstdc++.a}) with file permissions
disallowing read-other (@samp{chmod a+x,o-r}).  If the shared libraries
have been used, the shared library segment can be cleaned using the
@samp{/usr/sbin/slibclean} command.

AIX 4.3 utilizes a ``large format'' archive to support both 32-bit and
64-bit object modules.  The routines provided in AIX 4.3.0 and AIX 4.3.1
to parse archive libraries did not handle the new format correctly.
These routines are used by GCC and result in error messages during
linking such as ``not a COFF file''.  The version of the routines shipped
with AIX 4.3.1 should work for a 32-bit environment.  The @option{-g}
option of the archive command may be used to create archives of 32-bit
objects using the original ``small format''.  A correct version of the
routines is shipped with AIX 4.3.2 and above.

Some versions of the AIX binder (linker) can fail with a relocation
overflow severe error when the @option{-bbigtoc} option is used to link
GCC-produced object files into an executable that overflows the TOC@.  A fix
for APAR IX75823 (OVERFLOW DURING LINK WHEN USING GCC AND -BBIGTOC) is
available from IBM Customer Support and from its
@uref{http://techsupport.services.ibm.com/,,techsupport.services.ibm.com}
website as PTF U455193.

The AIX 4.3.2.1 linker (bos.rte.bind_cmds Level 4.3.2.1) will dump core
with a segmentation fault when invoked by any version of GCC@.  A fix for
APAR IX87327 is available from IBM Customer Support and from its
@uref{http://techsupport.services.ibm.com/,,techsupport.services.ibm.com}
website as PTF U461879.  This fix is incorporated in AIX 4.3.3 and above.

The initial assembler shipped with AIX 4.3.0 generates incorrect object
files.  A fix for APAR IX74254 (64BIT DISASSEMBLED OUTPUT FROM COMPILER FAILS
TO ASSEMBLE/BIND) is available from IBM Customer Support and from its
@uref{http://techsupport.services.ibm.com/,,techsupport.services.ibm.com}
website as PTF U453956.  This fix is incorporated in AIX 4.3.1 and above.

AIX provides National Language Support (NLS)@.  Compilers and assemblers
use NLS to support locale-specific representations of various data
formats including floating-point numbers (e.g., @samp{.}  vs @samp{,} for
separating decimal fractions).  There have been problems reported where
GCC does not produce the same floating-point formats that the assembler
expects.  If one encounters this problem, set the @env{LANG}
environment variable to @samp{C} or @samp{En_US}.

By default, GCC for AIX 4.1 and above produces code that can be used on
both Power or PowerPC processors.

A default can be specified with the @option{-mcpu=@var{cpu_type}}
switch and using the configure option @option{--with-cpu-@var{cpu_type}}.

@html
</p>
<hr>
@end html
@heading @anchor{m32r-*-elf}m32r-*-elf
Mitsubishi M32R processor.
This configuration is intended for embedded systems.

@html
</p>
<hr>
@end html
@heading @anchor{m68000-hp-bsd}m68000-hp-bsd
HP 9000 series 200 running BSD@.  Note that the C compiler that comes
with this system cannot compile GCC; contact @email{law@@cygnus.com}
to get binaries of GCC for bootstrapping.

@html
</p>
<hr>
@end html
@heading @anchor{m6811-elf}m6811-elf
Motorola 68HC11 family micro controllers.  These are used in embedded
applications.  There are no standard Unix configurations.

@html
</p>
<hr>
@end html
@heading @anchor{m6812-elf}m6812-elf
Motorola 68HC12 family micro controllers.  These are used in embedded
applications.  There are no standard Unix configurations.

@html
</p>
<hr>
@end html
@heading @anchor{m68k-altos}m68k-altos
Altos 3068.  You must use the GNU assembler, linker and debugger.
Also, you must fix a kernel bug.

@html
</p>
<hr>
@end html
@heading @anchor{m68k-apple-aux}m68k-apple-aux
Apple Macintosh running A/UX@.
You may configure GCC  to use either the system assembler and
linker or the GNU assembler and linker.  You should use the GNU configuration
if you can, especially if you also want to use G++.  You enable
that configuration with the @option{--with-gnu-as} and @option{--with-gnu-ld}
options to @code{configure}.

Note the C compiler that comes
with this system cannot compile GCC@.  You can find binaries of GCC
for bootstrapping on @code{jagubox.gsfc.nasa.gov}.
You will also a patched version of @file{/bin/ld} there that
raises some of the arbitrary limits found in the original.

@html
</p>
<hr>
@end html
@heading @anchor{m68k-att-sysv}m68k-att-sysv
AT&T 3b1, a.k.a.@: 7300 PC@.  This version of GCC cannot
be compiled with the system C compiler, which is too buggy.
You will need to get a previous version of GCC and use it to
bootstrap.  Binaries are available from the OSU-CIS archive, at
@uref{ftp://archive.cis.ohio-state.edu/pub/att7300/}.

@html
</p>
<hr>
@end html
@heading @anchor{m68k-bull-sysv}m68k-bull-sysv
Bull DPX/2 series 200 and 300 with BOS-2.00.45 up to BOS-2.01.  GCC works
either with native assembler or GNU assembler.  You can use
GNU assembler with native COFF generation by providing @option{--with-gnu-as} to
the configure script or use GNU assembler with stabs-in-COFF encapsulation
by providing @samp{--with-gnu-as --stabs}.  For any problem with the native
assembler or for availability of the DPX/2 port of GAS, contact
@email{F.Pierresteguy@@frcl.bull.fr}.

@html
</p>
<hr>
@end html
@heading @anchor{m68k-crds-unox}m68k-crds-unox
Use @samp{configure unos} for building on Unos.

The Unos assembler is named @code{casm} instead of @code{as}.  For some
strange reason linking @file{/bin/as} to @file{/bin/casm} changes the
behavior, and does not work.  So, when installing GCC, you should
install the following script as @file{as} in the subdirectory where
the passes of GCC are installed:

@example
#!/bin/sh
casm $*
@end example

The default Unos library is named @file{libunos.a} instead of
@file{libc.a}.  To allow GCC to function, either change all
references to @option{-lc} in @file{gcc.c} to @option{-lunos} or link
@file{/lib/libc.a} to @file{/lib/libunos.a}.

@cindex @code{alloca}, for Unos
When compiling GCC with the standard compiler, to overcome bugs in
the support of @code{alloca}, do not use @option{-O} when making stage 2.
Then use the stage 2 compiler with @option{-O} to make the stage 3
compiler.  This compiler will have the same characteristics as the usual
stage 2 compiler on other systems.  Use it to make a stage 4 compiler
and compare that with stage 3 to verify proper compilation.

(Perhaps simply defining @code{ALLOCA} in @file{x-crds} as described in
the comments there will make the above paragraph superfluous.  Please
inform us of whether this works.)

Unos uses memory segmentation instead of demand paging, so you will need
a lot of memory.  5 Mb is barely enough if no other tasks are running.
If linking @file{cc1} fails, try putting the object files into a library
and linking from that library.

@html
</p>
<hr>
@end html
@heading @anchor{m68k-hp-hpux}m68k-hp-hpux
HP 9000 series 300 or 400 running HP-UX@.  HP-UX version 8.0 has a bug in
the assembler that prevents compilation of GCC@.  This
bug manifests itself during the first stage of compilation, while
building @file{libgcc2.a}:

@smallexample
_floatdisf
cc1: warning: `-g' option not supported on this version of GCC
cc1: warning: `-g1' option not supported on this version of GCC
./xgcc: Internal compiler error: program as got fatal signal 11
@end smallexample

A patched version of the assembler is available as the file
@uref{ftp://altdorf.ai.mit.edu/archive/cph/hpux-8.0-assembler}.  If you
have HP software support, the patch can also be obtained directly from
HP, as described in the following note:

@quotation
This is the patched assembler, to patch SR#1653-010439, where the
assembler aborts on floating point constants.

The bug is not really in the assembler, but in the shared library
version of the function ``cvtnum(3c)''.  The bug on ``cvtnum(3c)'' is
SR#4701-078451.  Anyway, the attached assembler uses the archive
library version of ``cvtnum(3c)'' and thus does not exhibit the bug.
@end quotation

This patch is also known as PHCO_4484.

In addition, if you wish to use gas, you must use
gas version 2.1 or later, and you must use the GNU linker version 2.1 or
later.  Earlier versions of gas relied upon a program which converted the
gas output into the native HP-UX format, but that program has not been
kept up to date.  gdb does not understand that native HP-UX format, so
you must use gas if you wish to use gdb.

On HP-UX version 8.05, but not on 8.07 or more recent versions, the
@code{fixproto} shell script triggers a bug in the system shell.  If you
encounter this problem, upgrade your operating system or use BASH (the
GNU shell) to run @code{fixproto}.  This bug will cause the fixproto
program to report an error of the form:

@example
./fixproto: sh internal 1K buffer overflow
@end example

To fix this, you can also change the first line of the fixproto script
to look like:

@example
#!/bin/ksh
@end example


@html
</p>
<hr>
@end html
@heading @anchor{m68k-*-nextstep*}m68k-*-nextstep*

Current GCC versions probably do not work on version 2 of the NeXT
operating system.

On NeXTStep 3.0, the Objective-C compiler does not work, due,
apparently, to a kernel bug that it happens to trigger.  This problem
does not happen on 3.1.

You absolutely @strong{must} use GNU sed and GNU make on this platform.


On NeXTSTEP 3.x where x < 3 the build of GCC will abort during  
stage1 with an error message like this:

@example
  _eh
  /usr/tmp/ccbbsZ0U.s:987:Unknown pseudo-op: .section
  /usr/tmp/ccbbsZ0U.s:987:Rest of line ignored. 1st junk character
  valued 95 (_).
@end example

The reason for this is the fact that NeXT's assembler for these
versions of the operating system does not support the @samp{.section}
pseudo op that's needed for full C++ exception functionality.

As NeXT's assembler is a derived work from GNU as, a free
replacement that does can be obtained at
@uref{ftp://ftp.next.peak.org:/next-ftp/next/apps/devtools/as.3.3.NIHS.s.tar.gz,,ftp://ftp.next.peak.org:/next-ftp/next/apps/devtools/as.3.3.NIHS.s.tar.gz}.

If you try to build the integrated C++ & C++ runtime libraries on this system
you will run into trouble with include files.  The way to get around this is
to use the following sequence.  Note you must have write permission to
the directory @var{prefix} you specified in the configuration process of GCC
for this sequence to work.

@example
  cd bld-gcc
  make all-texinfo all-bison all-byacc all-binutils all-gas all-ld
  cd gcc
  make bootstrap
  make install-headers-tar
  cd ..
  make bootstrap3
@end example

@html
</p>
<hr>
@end html
@heading @anchor{m68k-ncr-*}m68k-ncr-*
On the Tower models 4@var{n}0 and 6@var{n}0, by default a process is not
allowed to have more than one megabyte of memory.  GCC cannot compile
itself (or many other programs) with @option{-O} in that much memory.

To solve this problem, reconfigure the kernel adding the following line
to the configuration file:

@smallexample
MAXUMEM = 4096
@end smallexample


@html
</p>
<hr>
@end html
@heading @anchor{m68k-sun}m68k-sun
Sun 3.  We do not provide a configuration file to use the Sun FPA by
default, because programs that establish signal handlers for floating
point traps inherently cannot work with the FPA@.

@html
</p>
<hr>
@end html
@heading @anchor{m68k-sun-sunos4.1.1}m68k-sun-sunos4.1.1

It is reported that you may need the GNU assembler on this platform.


@html
</p>
<hr>
@end html
@heading @anchor{m88k-*-svr3}m88k-*-svr3
Motorola m88k running the AT&T/Unisoft/Motorola V.3 reference port.
These systems tend to use the Green Hills C, revision 1.8.5, as the
standard C compiler.  There are apparently bugs in this compiler that
result in object files differences between stage 2 and stage 3.  If this
happens, make the stage 4 compiler and compare it to the stage 3
compiler.  If the stage 3 and stage 4 object files are identical, this
suggests you encountered a problem with the standard C compiler; the
stage 3 and 4 compilers may be usable.

It is best, however, to use an older version of GCC for bootstrapping
if you have one.

@html
</p>
<hr>
@end html
@heading @anchor{m88k-*-dgux}m88k-*-dgux
Motorola m88k running DG/UX@.  To build 88open BCS native or cross
compilers on DG/UX, specify the configuration name as
@samp{m88k-*-dguxbcs} and build in the 88open BCS software development
environment.  To build ELF native or cross compilers on DG/UX, specify
@samp{m88k-*-dgux} and build in the DG/UX ELF development environment.
You set the software development environment by issuing
@samp{sde-target} command and specifying either @samp{m88kbcs} or
@samp{m88kdguxelf} as the operand.

If you do not specify a configuration name, @file{configure} guesses the
configuration based on the current software development environment.

@html
</p>
<hr>
@end html
@heading @anchor{m88k-tektronix-sysv3}m88k-tektronix-sysv3
Tektronix XD88 running UTekV 3.2e.  Do not turn on
optimization while building stage1 if you bootstrap with
the buggy Green Hills compiler.  Also, the bundled LAI
System V NFS is buggy so if you build in an NFS mounted
directory, start from a fresh reboot, or avoid NFS all together.
Otherwise you may have trouble getting clean comparisons
between stages.

@html
</p>
<hr>
@end html
@heading @anchor{mips-*-*}mips-*-*
If you use the 1.31 version of the MIPS assembler (such as was shipped
with Ultrix 3.1), you will need to use the @option{-fno-delayed-branch} switch
when optimizing floating point code.  Otherwise, the assembler will
complain when the GCC compiler fills a branch delay slot with a
floating point instruction, such as @code{add.d}.

If on a MIPS system you get an error message saying ``does not have gp
sections for all it's [sic] sectons [sic]'', don't worry about it.  This
happens whenever you use GAS with the MIPS linker, but there is not
really anything wrong, and it is okay to use the output file.  You can
stop such warnings by installing the GNU linker.

It would be nice to extend GAS to produce the gp tables, but they are
optional, and there should not be a warning about their absence.

Users have reported some problems with version 2.0 of the MIPS
compiler tools that were shipped with Ultrix 4.1.  Version 2.10
which came with Ultrix 4.2 seems to work fine.

Users have also reported some problems with version 2.20 of the
MIPS compiler tools that were shipped with RISC/os 4.x.  The earlier
version 2.11 seems to work fine.

Some versions of the MIPS linker will issue an assertion failure
when linking code that uses @code{alloca} against shared
libraries on RISC-OS 5.0, and DEC's OSF/1 systems.  This is a bug
in the linker, that is supposed to be fixed in future revisions.
To protect against this, GCC passes @option{-non_shared} to the
linker unless you pass an explicit @option{-shared} or
@option{-call_shared} switch.

@heading @anchor{mips-mips-bsd}mips-mips-bsd
MIPS machines running the MIPS operating system in BSD mode.  It's
possible that some old versions of the system lack the functions
@code{memcpy}, @code{memmove}, @code{memcmp}, and @code{memset}.  If your
system lacks these, you must remove or undo the definition of
@code{TARGET_MEM_FUNCTIONS} in @file{mips-bsd.h}.

If you use the MIPS C compiler to bootstrap, it may be necessary
to increase its table size for switch statements with the
@option{-Wf,-XNg1500} option.  If you use the @option{-O2}
optimization option, you also need to use @option{-Olimit 3000}.
Both of these options are automatically generated in the
@file{Makefile} that the shell script @file{configure} builds.
If you override the @code{CC} make variable and use the MIPS
compilers, you may need to add @option{-Wf,-XNg1500 -Olimit 3000}.

@html
</p>
<hr>
@end html
@heading @anchor{mips-dec-*}mips-dec-*
MIPS-based DECstations can support three different personalities:
Ultrix, DEC OSF/1, and OSF/rose.  (Alpha-based DECstation products have
a configuration name beginning with @samp{alpha*-dec}.)  To configure GCC
for these platforms use the following configurations:

@table @samp
@item mips-dec-ultrix
Ultrix configuration.

@item mips-dec-osf1
DEC's version of OSF/1.

@item mips-dec-osfrose
Open Software Foundation reference port of OSF/1 which uses the
OSF/rose object file format instead of ECOFF@.  Normally, you
would not select this configuration.
@end table

If you use the MIPS C compiler to bootstrap, it may be necessary
to increase its table size for switch statements with the
@option{-Wf,-XNg1500} option.  If you use the @option{-O2}
optimization option, you also need to use @option{-Olimit 3000}.
Both of these options are automatically generated in the
@file{Makefile} that the shell script @file{configure} builds.
If you override the @code{CC} make variable and use the MIPS
compilers, you may need to add @option{-Wf,-XNg1500 -Olimit 3000}.

@html
</p>
<hr>
@end html
@heading @anchor{mips-mips-riscos*}mips-mips-riscos*
If you use the MIPS C compiler to bootstrap, it may be necessary
to increase its table size for switch statements with the
@option{-Wf,-XNg1500} option.  If you use the @option{-O2}
optimization option, you also need to use @option{-Olimit 3000}.
Both of these options are automatically generated in the
@file{Makefile} that the shell script @file{configure} builds.
If you override the @code{CC} make variable and use the MIPS
compilers, you may need to add @samp{-Wf,-XNg1500 -Olimit 3000}.

MIPS computers running RISC-OS can support four different
personalities: default, BSD 4.3, System V.3, and System V.4
(older versions of RISC-OS don't support V.4).  To configure GCC
for these platforms use the following configurations:

@table @samp
@item mips-mips-riscos@var{rev}
Default configuration for RISC-OS, revision @var{rev}.

@item mips-mips-riscos@var{rev}bsd
BSD 4.3 configuration for RISC-OS, revision @var{rev}.

@item mips-mips-riscos@var{rev}sysv4
System V.4 configuration for RISC-OS, revision @var{rev}.

@html
</p>
<hr>
@end html
@item mips-mips-riscos@var{rev}sysv
System V.3 configuration for RISC-OS, revision @var{rev}.
@end table

The revision @code{rev} mentioned above is the revision of
RISC-OS to use.  You must reconfigure GCC when going from a
RISC-OS revision 4 to RISC-OS revision 5.  This has the effect of
avoiding a linker bug.

@html
</p>
<hr>
@end html
@heading @anchor{mips-sgi-irix4}mips-sgi-irix4

In order to compile GCC on an SGI running IRIX 4, the ``c.hdr.lib''
option must be installed from the CD-ROM supplied from Silicon Graphics.
This is found on the 2nd CD in release 4.0.1.

On IRIX version 4.0.5F, and perhaps on some other versions as well,
there is an assembler bug that reorders instructions incorrectly.  To
work around it, specify the target configuration
@samp{mips-sgi-irix4loser}.  This configuration inhibits assembler
optimization.

In a compiler configured with target @samp{mips-sgi-irix4}, you can turn
off assembler optimization by using the @option{-noasmopt} option.  This
compiler option passes the option @option{-O0} to the assembler, to
inhibit reordering.

The @option{-noasmopt} option can be useful for testing whether a problem
is due to erroneous assembler reordering.  Even if a problem does not go
away with @option{-noasmopt}, it may still be due to assembler
reordering---perhaps GCC itself was miscompiled as a result.

You may get the following warning on IRIX 4 platforms, it can be safely
ignored.
@example
  warning: foo.o does not have gp tables for all its sections.
@end example

@html
</p>
<hr>
@end html
@heading @anchor{mips-sgi-irix5}mips-sgi-irix5

This configuration has considerable problems, which will be fixed in a
future release.

In order to compile GCC on an SGI running IRIX 5, the ``compiler_dev.hdr''
subsystem must be installed from the IDO CD-ROM supplied by Silicon
Graphics.  It is also available for download from
@uref{http://www.sgi.com/developers/devtools/apis/ido.html,,http://www.sgi.com/developers/devtools/apis/ido.html}.

@code{make compare} may fail on version 5 of IRIX unless you add
@option{-save-temps} to @code{CFLAGS}.  On these systems, the name of the
assembler input file is stored in the object file, and that makes
comparison fail if it differs between the @code{stage1} and
@code{stage2} compilations.  The option @option{-save-temps} forces a
fixed name to be used for the assembler input file, instead of a
randomly chosen name in @file{/tmp}.  Do not add @option{-save-temps}
unless the comparisons fail without that option.  If you do you
@option{-save-temps}, you will have to manually delete the @samp{.i} and
@samp{.s} files after each series of compilations.

If you use the MIPS C compiler to bootstrap, it may be necessary
to increase its table size for switch statements with the
@option{-Wf,-XNg1500} option.  If you use the @option{-O2}
optimization option, you also need to use @option{-Olimit 3000}.

To enable debugging under IRIX 5, you must use GNU @command{as} 2.11.2
or later, 
and use the @option{--with-gnu-as} configure option when configuring GCC.
GNU @command{as} is distributed as part of the binutils package.
When using release 2.11.2, you need to apply a patch 
@uref{http://sources.redhat.com/ml/binutils/2001-07/msg00352.html,,http://sources.redhat.com/ml/binutils/2001-07/msg00352.html}
which will be included in the next release of binutils.

When building GCC, the build process loops rebuilding @command{cc1} over
and over again.  This happens on @samp{mips-sgi-irix5.2}, and possibly
other platforms.  It has been reported that this is a known bug in the
@command{make} shipped with IRIX 5.2.  We recommend you use GNU
@command{make} instead of the vendor supplied @command{make} program;
however, you may have success with @command{smake} on IRIX 5.2 if you do
not have GNU @command{make} available.

@html
</p>
<hr>
@end html
@heading @anchor{mips-sgi-irix6}mips-sgi-irix6

If you are using IRIX @command{cc} as your bootstrap compiler, you must
ensure that the N32 ABI is in use.  To test this, compile a simple C
file with @command{cc} and then run @command{file} on the
resulting object file.  The output should look like:

@example
test.o: ELF N32 MSB @dots{}
@end example

If you see:

@example
test.o: ELF 32-bit MSB @dots{}
@end example

or

@example
test.o: ELF 64-bit MSB @dots{}
@end example

then your version of @command{cc} uses the O32 or N64 ABI by default.  You
should set the environment variable @env{CC} to @samp{cc -n32}
before configuring GCC@.

GCC on IRIX 6 is usually built to support both the N32 and N64 ABIs.  If
you build GCC on a system that doesn't have the N64 libraries installed,
you need to configure with @option{--disable-multilib} so GCC doesn't
try to use them.  Look for @file{/usr/lib64/libc.so.1} to see if you
have the 64-bit libraries installed.

You must @emph{not} use GNU @command{as} (which isn't built anyway as of
binutils 2.11.2) on IRIX 6 platforms; doing so will only cause problems.

GCC does not currently support generating O32 ABI binaries in the
@samp{mips-sgi-irix6} configurations.  It is possible to create a GCC
with O32 ABI only support by configuring it for the @samp{mips-sgi-irix5}
target and using a patched GNU @command{as} 2.11.2 as documented in the
@uref{#mips-sgi-irix5,,@samp{mips-sgi-irix5}} section above.  Using the
native assembler requires patches to GCC which will be included in a
future release.  It is
expected that O32 ABI support will be available again in a future release.

The @option{--enable-threads} option doesn't currently work, a patch is
in preparation for a future release.  The @option{--enable-libgcj}
option is disabled by default: IRIX 6 uses a very low default limit
(20480) for the command line length.  Although libtool contains a
workaround for this problem, at least the N64 @samp{libgcj} is known not
to build despite this, running into an internal error of the native
@command{ld}.  A sure fix is to increase this limit (@samp{ncargs}) to
its maximum of 262144 bytes.  If you have root access, you can use the
@command{systune} command to do this.

GCC does not correctly pass/return structures which are
smaller than 16 bytes and which are not 8 bytes.  The problem is very
involved and difficult to fix.  It affects a number of other targets also,
but IRIX 6 is affected the most, because it is a 64 bit target, and 4 byte
structures are common.  The exact problem is that structures are being padded
at the wrong end, e.g.@: a 4 byte structure is loaded into the lower 4 bytes
of the register when it should be loaded into the upper 4 bytes of the
register.

GCC is consistent with itself, but not consistent with the SGI C compiler
(and the SGI supplied runtime libraries), so the only failures that can
happen are when there are library functions that take/return such
structures. There are very few such library functions.  Currently this
is known to affect @code{inet_ntoa}, @code{inet_lnaof},
@code{inet_netof}, @code{inet_makeaddr}, and @code{semctl}.  Until the
bug is fixed, GCC contains workarounds for the known affected functions.

See @uref{http://freeware.sgi.com/,,http://freeware.sgi.com/} for more
information about using GCC on IRIX platforms.

@html
</p>
<hr>
@end html
@heading @anchor{mips-sony-sysv}mips-sony-sysv
Sony MIPS NEWS@.  This works in NEWSOS 5.0.1, but not in 5.0.2 (which
uses ELF instead of COFF)@.  Support for 5.0.2 will probably be provided
soon by volunteers.  In particular, the linker does not like the
code generated by GCC when shared libraries are linked in.


@html
</p>
<hr>
@end html
@heading @anchor{ns32k-encore}ns32k-encore
Encore ns32000 system.  Encore systems are supported only under BSD@.

@html
</p>
<hr>
@end html
@heading @anchor{ns32k-*-genix}ns32k-*-genix
National Semiconductor ns32000 system.  Genix has bugs in @code{alloca}
and @code{malloc}; you must get the compiled versions of these from GNU
Emacs.

@html
</p>
<hr>
@end html
@heading @anchor{ns32k-sequent}ns32k-sequent
Go to the Berkeley universe before compiling.

@html
</p>
<hr>
@end html
@heading @anchor{ns32k-utek}ns32k-utek
UTEK ns32000 system (``merlin'').  The C compiler that comes with this
system cannot compile GCC; contact @samp{tektronix!reed!mason} to get
binaries of GCC for bootstrapping.


@html
</p>
<hr>
@end html
@heading @anchor{powerpc*-*-*}powerpc-*-*

You can specify a default version for the @option{-mcpu=@var{cpu_type}}
switch by using the configure option @option{--with-cpu-@var{cpu_type}}.

@html
</p>
<hr>
@end html
@heading @anchor{powerpc-*-darwin*}powerpc-*-darwin*
PowerPC running Darwin (Mac OS X kernel).

GCC 3.0 does not support Darwin, but 3.1 and later releases will work.

Pre-installed versions of Mac OS X may not include any developer tools,
meaning that you will not be able to build GCC from source.  Tool
binaries are available at
@uref{http://www.opensource.apple.com/projects/darwin} (free
registration required).

Versions of the assembler prior to ``cctools-364'' cannot handle the
4-argument form of rlwinm and related mask-using instructions.  Darwin
1.3 (Mac OS X 10.0) uses cctools-353 for instance.  To get cctools-364,
check out @file{cctools} with tag @samp{Apple-364}, build it, and
install the assembler as @file{usr/bin/as}.  See
@uref{http://www.opensource.apple.com/tools/cvs/docs.html} for details.

Also, the default stack limit of 512K is too small, and a bootstrap will
typically fail when self-compiling @file{expr.c}.  Set the stack to 800K
or more, for instance by doing @samp{limit stack 800}.  It's also
convenient to use the GNU preprocessor instead of Apple's during the
first stage of bootstrapping; this is automatic when doing @samp{make
bootstrap}, but to do it from the toplevel objdir you will need to say
@samp{make CC='cc -no-cpp-precomp' bootstrap}.

Note that the version of GCC shipped by Apple typically includes a
number of extensions not available in a standard GCC release.  These
extensions are generally specific to Mac programming.

@html
</p>
<hr>
@end html
@heading @anchor{powerpc-*-elf}powerpc-*-elf, powerpc-*-sysv4
PowerPC system in big endian mode, running System V.4.

@html
</p>
<hr>
@end html
@heading @anchor{powerpc-*-linux-gnu*}powerpc-*-linux-gnu*

You will need
@uref{ftp://ftp.varesearch.com/pub/support/hjl/binutils,,binutils 2.9.4.0.8}
or newer for a working GCC@.  It is strongly recommended to recompile binutils
if you initially built it with gcc-2.7.2.x.

@html
</p>
<hr>
@end html
@heading @anchor{powerpc-*-netbsd*}powerpc-*-netbsd*
PowerPC system in big endian mode running NetBSD@.  To build the
documentation you will need Texinfo version 4.0 (NetBSD 1.5.1 included
Texinfo version 3.12).

@html
</p>
<hr>
@end html
@heading @anchor{powerpc-*-eabiaix}powerpc-*-eabiaix
Embedded PowerPC system in big endian mode with @option{-mcall-aix} selected as
the default.

@html
</p>
<hr>
@end html
@heading @anchor{powerpc-*-eabisim}powerpc-*-eabisim
Embedded PowerPC system in big endian mode for use in running under the
PSIM simulator.

@html
</p>
<hr>
@end html
@heading @anchor{powerpc-*-eabi}powerpc-*-eabi
Embedded PowerPC system in big endian mode.

@html
</p>
<hr>
@end html
@heading @anchor{powerpcle-*-elf}powerpcle-*-elf, powerpcle-*-sysv4
PowerPC system in little endian mode, running System V.4.

@html
</p>
<hr>
@end html
@heading @anchor{powerpcle-*-eabisim}powerpcle-*-eabisim
Embedded PowerPC system in little endian mode for use in running under
the PSIM simulator.

@html
</p>
<hr>
@end html
@heading @anchor{powerpcle-*-eabi}powerpcle-*-eabi
Embedded PowerPC system in little endian mode.

@html
</p>
<hr>
@end html
@heading @anchor{powerpcle-*-winnt}powerpcle-*-winnt, powerpcle-*-pe
PowerPC system in little endian mode running Windows NT@.

@html
</p>
<hr>
@end html
@heading @anchor{romp-*-aos}romp-*-aos, romp-*-mach
The only operating systems supported for the IBM RT PC are AOS and
MACH@.  GCC does not support AIX running on the RT@.  We recommend you
compile GCC with an earlier version of itself; if you compile GCC
with @command{hc}, the Metaware compiler, it will work, but you will get
mismatches between the stage 2 and stage 3 compilers in various files.
These errors are minor differences in some floating-point constants and
can be safely ignored; the stage 3 compiler is correct.

@html
</p>
<hr>
@end html
@heading @anchor{s390-*-linux*}s390-*-linux*
S/390 system running Linux for S/390@. 

@html
</p>
<hr>
@end html
@heading @anchor{s390x-*-linux*}s390x-*-linux*
zSeries system (64 Bit) running Linux for zSeries@. 

@html
</p>
<hr>
@end html
@c Please use Solaris 2 to refer to all release of Solaris, starting
@c with 2.0 until 2.6, 7, and 8.  Solaris 1 was a marketing name for
@c SunOS 4 releases which we don't use to avoid confusion.  Solaris
@c alone is too unspecific and must be avoided.
@heading @anchor{*-*-solaris2*}*-*-solaris2*

Sun does not ship a C compiler with Solaris 2.  To bootstrap and install
GCC you first have to install a pre-built compiler, see our
@uref{binaries.html,,binaries page} for details.

The Solaris 2 @command{/bin/sh} will often fail to configure
@file{libstdc++-v3}, @file{boehm-gc} or
@file{libjava}.  If you encounter this problem, set @env{CONFIG_SHELL} to
@command{/bin/ksh} in your environment and run @command{make bootstrap} again.
Another possibility that sometimes helps is to remove
@file{*-*-solaris2*/config.cache}.

Solaris 2 comes with a number of optional OS packages.  Some of these
packages are needed to use GCC fully, namely @code{SUNWarc},
@code{SUNWbtool}, @code{SUNWesu}, @code{SUNWhea}, @code{SUNWlibm},
@code{SUNWsprot}, and @code{SUNWtoo}.  If you did not install all
optional packages when installing Solaris 2, you will need to verify that
the packages that GCC needs are installed.

To check whether an optional package is installed, use
the @command{pkginfo} command.  To add an optional package, use the
@command{pkgadd} command.  For further details, see the Solaris 2
documentation.

Trying to use the linker and other tools in
@file{/usr/ucb} to install GCC has been observed to cause trouble.
For example, the linker may hang indefinitely.  The fix is to remove
@file{/usr/ucb} from your @env{PATH}.

All releases of GNU binutils prior to 2.11.2 have known bugs on this
platform.  We recommend the use of GNU binutils 2.11.2 or the vendor
tools (Sun @command{as}, Sun @command{ld}).

Sun bug 4296832 turns up when compiling X11 headers with GCC 2.95 or
newer: @command{g++} will complain that types are missing.  These headers assume
that omitting the type means @code{int}; this assumption worked for C89 but
is wrong for C++, and is now wrong for C99 also.

@command{g++} accepts such (invalid) constructs with the option
@option{-fpermissive}; it
will assume that any missing type is @code{int} (as defined by C89).

There are patches for Solaris 2.6 (105633-56 or newer for SPARC,
106248-42 or newer for Intel), Solaris 7 (108376-21 or newer for SPARC,
108377-20 for Intel), and Solaris 8 (108652-24 or newer for SPARC,
108653-22 for Intel) that fix this bug.

@html
</p>
<hr>
@end html
@heading @anchor{sparc-sun-solaris2*}sparc-sun-solaris2*

Sun @command{as} 4.x is broken in that it cannot cope with long symbol names.
A typical error message might look similar to the following:

@samp{/usr/ccs/bin/as: "/var/tmp/ccMsw135.s", line 11041:
error: can't compute value of an expression involving an external symbol.}

This is Sun bug 4237974.  This is fixed with patch 108908-02 for Solaris
2.6 and has been fixed in later (5.x) versions of the assembler,
starting with Solaris 7.

Starting with Solaris 7, the operating system is capable of executing
64-bit SPARC V9 binaries.  GCC 3.1 and later should properly support
this.  GCC 3.0 lacks the infrastructure necessary to support this
configuration properly.  However, if all you want is code tuned for
the UltraSPARC CPU, you should try the @option{-mtune=ultrasparc}
option instead, which should be safe from those bugs and produce code
that, unlike full 64-bit code, can still run on non-UltraSPARC
machines.

@html
</p>
<hr>
@end html
@heading @anchor{sparc-sun-solaris2.7}sparc-sun-solaris2.7

Sun patch 107058-01 (1999-01-13) for Solaris 7/SPARC triggers a bug in
the dynamic linker.  This problem (Sun bug 4210064) affects GCC 2.8
and later, including all EGCS releases.  Sun formerly recommended
107058-01 for all Solaris 7 users, but around 1999-09-01 it started to
recommend it only for people who use Sun's compilers.

Here are some workarounds to this problem:
@itemize @bullet
@item
Do not install Sun patch 107058-01 until after Sun releases a
complete patch for bug 4210064.  This is the simplest course to take,
unless you must also use Sun's C compiler.  Unfortunately 107058-01
is preinstalled on some new Solaris 7-based hosts, so you may have to
back it out.

@item
Copy the original, unpatched Solaris 7
@command{/usr/ccs/bin/as} into
@command{/usr/local/lib/gcc-lib/sparc-sun-solaris2.7/3.0/as},
adjusting the latter name to fit your local conventions and software
version numbers.

@item
Install Sun patch 106950-03 (1999-05-25) or later.  Nobody with
both 107058-01 and 106950-03 installed has reported the bug with GCC
and Sun's dynamic linker.  This last course of action is riskiest,
for two reasons.  First, you must install 106950 on all hosts that
run code generated by GCC; it doesn't suffice to install it only on
the hosts that run GCC itself.  Second, Sun says that 106950-03 is
only a partial fix for bug 4210064, but Sun doesn't know whether the
partial fix is adequate for GCC@.  Revision -08 or later should fix
the bug.  The current (as of 2001-09-24) revision is -14, and is included in
the Solaris 7 Recommended Patch Cluster. 
@end itemize


@html
<p>
<hr>
@end html
@heading @anchor{*-*-solaris2.8}*-*-solaris2.8

The Solaris 8 linker fails to link some @samp{libjava} programs if
previously-installed GCC java libraries already exist in the configured
prefix.  For this reason, @samp{libgcj} is disabled by default on Solaris 8.
If you use GNU @command{ld}, or if you don't have a previously-installed @samp{libgcj} in
the same prefix, use @option{--enable-libgcj} to build and install the
Java libraries.

@html
<p>
<hr>
@end html
@heading @anchor{sparc-sun-sunos4*}sparc-sun-sunos4*

A bug in the SunOS 4 linker will cause it to crash when linking
@option{-fPIC} compiled objects (and will therefore not allow you to build
shared libraries).

To fix this problem you can either use the most recent version of
binutils or get the latest SunOS 4 linker patch (patch ID 100170-10)
from Sun's patch site.

Sometimes on a Sun 4 you may observe a crash in the program
@command{genflags} or @command{genoutput} while building GCC.  This is said to
be due to a bug in @command{sh}.  You can probably get around it by running
@command{genflags} or @command{genoutput} manually and then retrying the
@command{make}.

@html
</p>
<hr>
@end html
@heading @anchor{sparc-unknown-linux-gnulibc1}sparc-unknown-linux-gnulibc1

It has been reported that you might need
@uref{ftp://ftp.yggdrasil.com/private/hjl,,binutils 2.8.1.0.23}
for this platform, too.


@html
</p>
<hr>
@end html
@heading @anchor{sparc-*-linux*}sparc-*-linux*

GCC versions 3.0 and higher require binutils 2.11.2 and glibc 2.2.4
or newer on this platform.  All earlier binutils and glibc
releases mishandled unaligned relocations on @code{sparc-*-*} targets.


@html
</p>
<hr>
@end html
@heading @anchor{sparc64-*-*}sparc64-*-*

GCC version 2.95 is not able to compile code correctly for
@code{sparc64} targets.  Users of the Linux kernel, at least,
can use the @code{sparc32} program to start up a new shell
invocation with an environment that causes @command{configure} to
recognize (via @samp{uname -a}) the system as @samp{sparc-*-*} instead.


@html
</p>
<hr>
@end html
@heading @anchor{#*-*-sysv*}*-*-sysv*
On System V release 3, you may get this error message
while linking:

@smallexample
ld fatal: failed to write symbol name @var{something}
 in strings table for file @var{whatever}
@end smallexample

This probably indicates that the disk is full or your ulimit won't allow
the file to be as large as it needs to be.

This problem can also result because the kernel parameter @code{MAXUMEM}
is too small.  If so, you must regenerate the kernel and make the value
much larger.  The default value is reported to be 1024; a value of 32768
is said to work.  Smaller values may also work.

On System V, if you get an error like this,

@example
/usr/local/lib/bison.simple: In function `yyparse':
/usr/local/lib/bison.simple:625: virtual memory exhausted
@end example

@noindent
that too indicates a problem with disk space, ulimit, or @code{MAXUMEM}.

On a System V release 4 system, make sure @file{/usr/bin} precedes
@file{/usr/ucb} in @code{PATH}.  The @code{cc} command in
@file{/usr/ucb} uses libraries which have bugs.

@html
</p>
<hr>
@end html
@heading @anchor{vax-dec-ultrix}vax-dec-ultrix
Don't try compiling with VAX C (@code{vcc}).  It produces incorrect code
in some cases (for example, when @code{alloca} is used).

@html
</p>
<hr>
@end html
@heading @anchor{we32k-*-*}we32k-*-*
These computers are also known as the 3b2, 3b5, 3b20 and other similar
names.  (However, the 3b1 is actually a 68000.)

Don't use @option{-g} when compiling with the system's compiler.  The
system's linker seems to be unable to handle such a large program with
debugging information.

The system's compiler runs out of capacity when compiling @file{stmt.c}
in GCC@.  You can work around this by building @file{cpp} in GCC
first, then use that instead of the system's preprocessor with the
system's C compiler to compile @file{stmt.c}.  Here is how:

@smallexample
mv /lib/cpp /lib/cpp.att
cp cpp /lib/cpp.gnu
echo '/lib/cpp.gnu -traditional $@{1+"$@@"@}' > /lib/cpp
chmod +x /lib/cpp
@end smallexample

The system's compiler produces bad code for some of the GCC
optimization files.  So you must build the stage 2 compiler without
optimization.  Then build a stage 3 compiler with optimization.
That executable should work.  Here are the necessary commands:

@smallexample
make LANGUAGES=c CC=stage1/xgcc CFLAGS="-Bstage1/ -g"
make stage2
make CC=stage2/xgcc CFLAGS="-Bstage2/ -g -O"
@end smallexample

You may need to raise the ULIMIT setting to build a C++ compiler,
as the file @file{cc1plus} is larger than one megabyte.

@html
</p>
<hr>
@end html
@heading @anchor{windows}Microsoft Windows (32 bit)

A port of GCC 2.95.x is included with the
@uref{http://www.cygwin.com/,,Cygwin environment}.

Current (as of early 2001) snapshots of GCC will build under Cygwin
without modification.

@html
</p>
<hr>
@end html
@heading @anchor{os2}OS/2

GCC does not currently support OS/2.  However, Andrew Zabolotny has been
working on a generic OS/2 port with pgcc.  The current code can be found
at @uref{http://www.goof.com/pcg/os2/,,http://www.goof.com/pcg/os2/}.

An older copy of GCC 2.8.1 is included with the EMX tools available at
@uref{ftp://ftp.leo.org/pub/comp/os/os2/leo/devtools/emx+gcc/,,
ftp://ftp.leo.org/pub/comp/os/os2/leo/devtools/emx+gcc/}.

@html
</p>
<hr>
@end html
@heading @anchor{older}Older systems

GCC contains support files for many older (1980s and early
1990s) Unix variants.  For the most part, support for these systems
has not been deliberately removed, but it has not been maintained for
several years and may suffer from bitrot.  Support from some systems
has been removed from GCC 3: fx80, ns32-ns-genix, pyramid, tahoe,
gmicro, spur; most of these targets had not been updated since GCC
version 1.

Support for older systems as targets for cross-compilation is less
problematic than support for them as hosts for GCC; if an enthusiast
wishes to make such a target work again (including resurrecting any
of the targets that never worked with GCC 2, starting from the last
CVS version before they were removed), patches
@uref{../contribute.html,,following the usual requirements}
would be likely to be accepted, since they should not affect the
support for more modern targets.

Support for old systems as hosts for GCC can cause problems if the
workarounds for compiler, library and operating system bugs affect the
cleanliness or maintainability of the rest of GCC@.  In some cases, to
bring GCC up on such a system, if still possible with current GCC, may
require first installing an old version of GCC which did work on that
system, and using it to compile a more recent GCC, to avoid bugs in
the vendor compiler.  Old releases of GCC 1 and GCC 2 are available in
the @file{old-releases} directory on the
@uref{../mirrors.html,,GCC mirror sites}.  Header bugs may generally
be avoided using @command{fixincludes}, but bugs or deficiencies in
libraries and the operating system may still cause problems.

For some systems, old versions of GNU binutils may also be useful,
and are available from @file{pub/binutils/old-releases} on
@uref{http://sources.redhat.com/mirrors.html,,sources.redhat.com mirror sites}.

Some of the information on specific systems above relates to
such older systems, but much of the information
about GCC on such systems (which may no longer be applicable to
current GCC) is to be found in the GCC texinfo manual.

@html
</p>
<hr>
@end html
@heading @anchor{elf_targets}all ELF targets (SVR4, Solaris 2, etc.)

C++ support is significantly better on ELF targets if you use the
@uref{./configure.html#with-gnu-ld,,GNU linker}; duplicate copies of
inlines, vtables and template instantiations will be discarded
automatically.


@html
</p>
<hr>
<p>
@end html
@ifhtml
@uref{./index.html,,Return to the GCC Installation page}
@end ifhtml
@end ifset

@c ***************************************************************************
@c Part 6 The End of the Document
@ifinfo
@comment node-name,     next,          previous, up
@node    Concept Index, , Specific, Top
@end ifinfo

@ifinfo
@unnumbered Concept Index

@printindex cp

@contents
@end ifinfo
@bye