@ifnothtml
@menu
* Configurations:: Configurations Supported by GCC.
-* Cross-Compiler:: Building and installing a cross-compiler.
@end menu
@end ifnothtml
In those cases, specify the build machine's @dfn{configuration name}
with the @option{--host} option; the host and target will default to be
-the same as the host machine. (If you are building a cross-compiler,
-see @ref{Cross-Compiler}.)
+the same as the host machine.
Here is an example:
@end enumerate
@ifnothtml
-@node Configurations, Cross-Compiler, , Old
+@node Configurations, , , Old
@section Configurations Supported by GCC
@end ifnothtml
@html
files @file{m68k.md}, @file{local.h}, @file{m68k.c},
@file{xm-local.h}, @file{t-local}, and @file{x-local}, all in the
directory @file{config/m68k}.
-
-@ifnothtml
-@node Cross-Compiler, , Configurations, Old
-@section Building and Installing a Cross-Compiler
-@end ifnothtml
-@html
-<h2>@anchor{Cross-Compiler}Building and Installing a Cross-Compiler</h2>
-@end html
-@cindex cross-compiler, installation
-
-GCC can function as a cross-compiler for many machines, but not all.
-
-@itemize @bullet
-@item
-Cross-compilers for the Mips as target using the Mips assembler
-currently do not work, because the auxiliary programs
-@file{mips-tdump.c} and @file{mips-tfile.c} can't be compiled on
-anything but a Mips. It does work to cross compile for a Mips
-if you use the GNU assembler and linker.
-
-@item
-Cross-compilers between machines with different floating point formats
-have not all been made to work. GCC now has a floating point
-emulator with which these can work, but each target machine description
-needs to be updated to take advantage of it.
-
-@item
-Cross-compilation between machines of different word sizes is
-somewhat problematic and sometimes does not work.
-@end itemize
-
-Since GCC generates assembler code, you probably need a
-cross-assembler that GCC can run, in order to produce object files.
-If you want to link on other than the target machine, you need a
-cross-linker as well. You also need header files and libraries suitable
-for the target machine that you can install on the host machine.
-
-@ifnothtml
-@menu
-* Steps of Cross:: Using a cross-compiler involves several steps
- that may be carried out on different machines.
-* Configure Cross:: Configuring a cross-compiler.
-* Tools and Libraries:: Where to put the linker and assembler, and the C library.
-* Cross Headers:: Finding and installing header files
- for a cross-compiler.
-* Build Cross:: Actually compiling the cross-compiler.
-@end menu
-@end ifnothtml
-
-@ifnothtml
-@node Steps of Cross, Configure Cross, , Cross-Compiler
-@subsection Steps of Cross-Compilation
-@end ifnothtml
-@html
-<h2>Steps of Cross-Compilation</h2>
-@end html
-
-To compile and run a program using a cross-compiler involves several
-steps:
-
-@itemize @bullet
-@item
-Run the cross-compiler on the host machine to produce assembler files
-for the target machine. This requires header files for the target
-machine.
-
-@item
-Assemble the files produced by the cross-compiler. You can do this
-either with an assembler on the target machine, or with a
-cross-assembler on the host machine.
-
-@item
-Link those files to make an executable. You can do this either with a
-linker on the target machine, or with a cross-linker on the host
-machine. Whichever machine you use, you need libraries and certain
-startup files (typically @file{crt@dots{}.o}) for the target machine.
-@end itemize
-
-It is most convenient to do all of these steps on the same host machine,
-since then you can do it all with a single invocation of GCC@. This
-requires a suitable cross-assembler and cross-linker. For some targets,
-the GNU assembler and linker are available.
-
-@ifnothtml
-@node Configure Cross, Tools and Libraries, Steps of Cross, Cross-Compiler
-@subsection Configuring a Cross-Compiler
-@end ifnothtml
-@html
-<h2>Configuring a Cross-Compiler</h2>
-@end html
-
-To build GCC as a cross-compiler, you start out by running
-@file{configure}. Use the @option{--target=@var{target}} to specify the
-target type. If @file{configure} was unable to correctly identify the
-system you are running on, also specify the @option{--build=@var{build}}
-option. For example, here is how to configure for a cross-compiler that
-produces code for an HP 68030 system running BSD on a system that
-@file{configure} can correctly identify:
-
-@smallexample
-./configure --target=m68k-hp-bsd4.3
-@end smallexample
-
-@ifnothtml
-@node Tools and Libraries, Cross Headers, Configure Cross, Cross-Compiler
-@subsection Tools and Libraries for a Cross-Compiler
-@end ifnothtml
-@html
-<h2>Tools and Libraries for a Cross-Compiler</h2>
-@end html
-
-If you have a cross-assembler and cross-linker available, you should
-install them now. Put them in the directory
-@file{/usr/local/@var{target}/bin}. Here is a table of the tools
-you should put in this directory:
-
-@table @file
-@item as
-This should be the cross-assembler.
-
-@item ld
-This should be the cross-linker.
-
-@item ar
-This should be the cross-archiver: a program which can manipulate
-archive files (linker libraries) in the target machine's format.
-
-@item ranlib
-This should be a program to construct a symbol table in an archive file.
-@end table
-
-The installation of GCC will find these programs in that directory,
-and copy or link them to the proper place to for the cross-compiler to
-find them when run later.
-
-The easiest way to provide these files is to build the Binutils package
-and GAS@. Configure them with the same @option{--host} and @option{--target}
-options that you use for configuring GCC, then build and install
-them. They install their executables automatically into the proper
-directory. Alas, they do not support all the targets that GCC
-supports.
-
-If you want to install libraries to use with the cross-compiler, such as
-a standard C library, put them in the directory
-@file{/usr/local/@var{target}/lib}; installation of GCC copies
-all the files in that subdirectory into the proper place for GCC to
-find them and link with them. Here's an example of copying some
-libraries from a target machine:
-
-@example
-ftp @var{target-machine}
-lcd /usr/local/@var{target}/lib
-cd /lib
-get libc.a
-cd /usr/lib
-get libg.a
-get libm.a
-quit
-@end example
-
-@noindent
-The precise set of libraries you'll need, and their locations on
-the target machine, vary depending on its operating system.
-
-@cindex start files
-Many targets require ``start files'' such as @file{crt0.o} and
-@file{crtn.o} which are linked into each executable; these too should be
-placed in @file{/usr/local/@var{target}/lib}. There may be several
-alternatives for @file{crt0.o}, for use with profiling or other
-compilation options. Check your target's definition of
-@code{STARTFILE_SPEC} to find out what start files it uses.
-Here's an example of copying these files from a target machine:
-
-@example
-ftp @var{target-machine}
-lcd /usr/local/@var{target}/lib
-prompt
-cd /lib
-mget *crt*.o
-cd /usr/lib
-mget *crt*.o
-quit
-@end example
-
-@ifnothtml
-@node Cross Headers, Build Cross, Tools and Libraries, Cross-Compiler
-@subsection Cross-Compilers and Header Files
-@end ifnothtml
-@html
-<h2>Cross-Compilers and Header Files</h2>
-@end html
-
-If you are cross-compiling a standalone program or a program for an
-embedded system, then you may not need any header files except the few
-that are part of GCC (and those of your program). However, if you
-intend to link your program with a standard C library such as
-@file{libc.a}, then you probably need to compile with the header files
-that go with the library you use.
-
-The GNU C compiler does not come with these files, because (1) they are
-system-specific, and (2) they belong in a C library, not in a compiler.
-
-If the GNU C library supports your target machine, then you can get the
-header files from there (assuming you actually use the GNU library when
-you link your program).
-
-If your target machine comes with a C compiler, it probably comes with
-suitable header files also. If you make these files accessible from the host
-machine, the cross-compiler can use them also.
-
-Otherwise, you're on your own in finding header files to use when
-cross-compiling.
-
-When you have found suitable header files, you should put them in the
-directory @file{/usr/local/@var{target}/include}, before building the
-cross compiler. Then installation will run fixincludes properly and
-install the corrected versions of the header files where the compiler
-will use them.
-
-Provide the header files before you build the cross-compiler, because
-the build stage actually runs the cross-compiler to produce parts of
-@file{libgcc.a}. (These are the parts that @emph{can} be compiled with
-GCC@.) Some of them need suitable header files.
-
-Here's an example showing how to copy the header files from a target
-machine. On the target machine, do this:
-
-@example
-(cd /usr/include; tar cf - .) > tarfile
-@end example
-
-Then, on the host machine, do this:
-
-@example
-ftp @var{target-machine}
-lcd /usr/local/@var{target}/include
-get tarfile
-quit
-tar xf tarfile
-@end example
-
-@ifnothtml
-@node Build Cross, , Cross Headers, Cross-Compiler
-@subsection Actually Building the Cross-Compiler
-@end ifnothtml
-@html
-<h2>Actually Building the Cross-Compiler</h2>
-@end html
-
-Now you can proceed just as for compiling a single-machine compiler
-through the step of building stage 1.
-
-Do not try to build stage 2 for a cross-compiler. It doesn't work to
-rebuild GCC as a cross-compiler using the cross-compiler, because
-that would produce a program that runs on the target machine, not on the
-host. For example, if you compile a 386-to-68030 cross-compiler with
-itself, the result will not be right either for the 386 (because it was
-compiled into 68030 code) or for the 68030 (because it was configured
-for a 386 as the host). If you want to compile GCC into 68030 code,
-whether you compile it on a 68030 or with a cross-compiler on a 386, you
-must specify a 68030 as the host when you configure it.
-
-To install the cross-compiler, use @samp{make install}, as usual.
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