Using and Porting the GNU Compiler Collection (GCC)
Here is the procedure for installing GNU CC on a GNU or Unix system. See VMS Install, for VMS systems. In this section we assume you compile in the same directory that contains the source files; see Other Dir, to find out how to compile in a separate directory on Unix systems.
You cannot install GNU C 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.
make distclean' to delete all files
that might be invalid. One of the files this deletes is
`Makefile'; if `make distclean' complains that `Makefile'
does not exist, it probably means that the directory is already suitably
clean.
/usr/bin' precedes
`/usr/ucb' in PATH. The cc command in
`/usr/ucb' uses libraries which have bugs.
c-parse.c' and
`cexp.c' are more recent than `c-parse.y' and `cexp.y'
and you do not plan to change the `.y' files.)
Bison versions older than Sept 8, 1988 will produce incorrect output
for `c-parse.c'.
as', `ld' or whatever is appropriate. This will enable the
compiler to find the proper tools for compilation of the program
`enquire'.
Alternatively, you can do subsequent compilation using a value of the
PATH environment variable such that the necessary GNU tools come
before the standard system tools.
configure' script.
The build machine is the system which you are using, the host machine is the system where you want to run the resulting compiler (normally the build machine), and the target machine is the system for which you want the compiler to generate code.
If you are building a compiler to produce code for the machine it runs
on (a native compiler), you normally do not need to specify any operands
to `configure'; it will try to guess the type of machine you are on
and use that as the build, host and target machines. So you don't need
to specify a configuration when building a native compiler unless
`configure' cannot figure out what your configuration is or guesses
wrong.
In those cases, specify the build machine's configuration name
with the `--host' option; the host and target will default to be
the same as the host machine. (If you are building a cross-compiler,
see Cross-Compiler.)
Here is an example:
./configure --host=sparc-sun-sunos4.1
A configuration name may be canonical or it may be more or less abbreviated.
A canonical configuration name has three parts, separated by dashes.
It looks like this: `cpu-company-system'.
(The three parts may themselves contain dashes; `configure'
can figure out which dashes serve which purpose.) For example,
`m68k-sun-sunos4.1' specifies a Sun 3.
You can also replace parts of the configuration by nicknames or aliases.
For example, `sun3' stands for `m68k-sun', so
`sun3-sunos4.1' is another way to specify a Sun 3. You can also
use simply `sun3-sunos', since the version of SunOS is assumed by
default to be version 4.
You can specify a version number after any of the system types, and some of the CPU types. In most cases, the version is irrelevant, and will be ignored. So you might as well specify the version if you know it.
See Configurations, for a list of supported configuration names and notes on many of the configurations. You should check the notes in that section before proceeding any further with the installation of GNU CC.
configure, you may also need to specify certain
additional options that describe variant hardware and software
configurations. These are `--with-gnu-as', `--with-gnu-ld',
`--with-stabs' and `--nfp'.
--with-gnu-as'
--with-gnu-as' option when you run
`configure'.
Using this option does not install GAS. It only modifies the output of GNU CC to work with GAS. Building and installing GAS is up to you.
Conversely, if you do not wish to use GAS and do not specify
`--with-gnu-as' when building GNU CC, it is up to you to make sure
that GAS is not installed. GNU CC searches for a program named
as in various directories; if the program it finds is GAS, then
it runs GAS. If you are not sure where GNU CC finds the assembler it is
using, try specifying `-v' when you run it.
The systems where it makes a difference whether you use GAS are
`hppa1.0-any-any', `hppa1.1-any-any',
`i386-any-sysv', `i386-any-isc',
`i860-any-bsd', `m68k-bull-sysv',
`m68k-hp-hpux', `m68k-sony-bsd',
`m68k-altos-sysv', `m68000-hp-hpux',
`m68000-att-sysv', `any-lynx-lynxos',
and `mips-any').
On any other system, `--with-gnu-as' has no effect.
On the systems listed above (except for the HP-PA, for ISC on the
386, and for `mips-sgi-irix5.*'), if you use GAS, you should also
use the GNU linker (and specify `--with-gnu-ld').
--with-gnu-ld'
--with-gnu-ld' if you plan to use the GNU
linker with GNU CC.
This option does not cause the GNU linker to be installed; it just modifies the behavior of GNU CC to work with the GNU linker.
--with-stabs'
Normally, GNU CC uses the ECOFF debugging format by default; if you
prefer BSD stabs, specify `--with-stabs' when you configure GNU
CC.
No matter which default you choose when you configure GNU CC, the user
can use the `-gcoff' and `-gstabs+' options to specify explicitly
the debug format for a particular compilation.
`--with-stabs' is meaningful on the ISC system on the 386, also, if
`--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.
`--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.
--nfp'
m68k-sun-sunosn' and
`m68k-isi-bsd'. On any other system, `--nfp' currently has no
effect, though perhaps there are other systems where it could usefully
make a difference.
--enable-haifa'
--disable-haifa'
--enable-haifa' to enable use of an experimental instruction
scheduler (from IBM Haifa). This may or may not produce better code.
Some targets on which it is known to be a win enable it by default; use
`--disable-haifa' to disable it in these cases. configure
will print out whether the Haifa scheduler is enabled when it is run.
--enable-threads=type'
posix'. The possibilities for type are `single',
`posix', `win32', `solaris', `irix' and `mach'.
--enable-checking'
The `configure' script searches subdirectories of the source
directory for other compilers that are to be integrated into GNU CC.
The GNU compiler for C++, called G++ is in a subdirectory named
`cp'. `configure' inserts rules into `Makefile' to build
all of those compilers.
Here we spell out what files will be set up by configure. Normally
you need not be concerned with these files.
config.h' is created that contains a `#include'
of the top-level config file for the machine you will run the compiler
on (see Config). This file is responsible for defining information
about the host machine. It includes `tm.h'.
The top-level config file is located in the subdirectory `config'.
Its name is always `xm-something.h'; usually
`xm-machine.h', but there are some exceptions.
If your system does not support symbolic links, you might want to
set up `config.h' to contain a `#include' command which
refers to the appropriate file.
tconfig.h' is created which includes the top-level config
file for your target machine. This is used for compiling certain
programs to run on that machine.
tm.h' is created which includes the
machine-description macro file for your target machine. It should be in
the subdirectory `config' and its name is often
`machine.h'.
--enable-nls'
--disable-nls'
--enable-nls' option enables Native Language Support (NLS),
which lets GCC output diagnostics in languages other than American
English. No translations are available yet, so the main users of this
option now are those translating GCC's diagnostics who want to test
their work. Once translations become available, Native Language Support
will become enabled by default. The `--disable-nls' option
disables NLS.
--with-included-gettext'
gettext libraries, and falls back on GCC's copy of the GNU
gettext library only if the host libraries do not suffice. The
`--with-included-gettext' option causes the build procedure to
prefer its copy of GNU gettext.
--with-catgets'
gettext but has the
inferior catgets interface, the GCC build procedure normally
ignores catgets and instead uses GCC's copy of the GNU
gettext library. The `--with-catgets' option causes the
build procedure to use the host's catgets in this situation.
configure.
/usr/local/lib'.
If you want to install its files somewhere else, specify
`--prefix=dir' when you run `configure'. Here dir
is a directory name to use instead of `/usr/local' for all purposes
with one exception: the directory `/usr/local/include' is searched
for header files no matter where you install the compiler. To override
this name, use the --with-local-prefix option below. The directory
you specify need not exist, but its parent directory must exist.
--with-local-prefix=dir' if you want the compiler to
search directory `dir/include' for locally installed header
files instead of `/usr/local/include'.
You should specify `--with-local-prefix' only if your site has
a different convention (not `/usr/local') for where to put
site-specific files.
The default value for `--with-local-prefix' is `/usr/local'
regardless of the value of `--prefix'. Specifying `--prefix'
has no effect on which directory GNU CC searches for local header files.
This may seem counterintuitive, but actually it is logical.
The purpose of `--prefix' is to specify where to install GNU CC. The local header files in `/usr/local/include'---if you put
any in that directory---are not part of GNU CC. They are part of other
programs---perhaps many others. (GNU CC installs its own header files
in another directory which is based on the `--prefix' value.)
Do not specify `/usr' as the `--with-local-prefix'! The
directory you use for `--with-local-prefix' 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 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 GNU CC. Perhaps they make this assumption because installing GNU CC creates the directory.
make LANGUAGES=c' in the compiler
directory.
`LANGUAGES=c' specifies that only the C compiler should be
compiled. The makefile normally builds compilers for all the supported
languages; currently, C, C++ and Objective C. However, C is the only
language that is sure to work when you build with other non-GNU C
compilers. In addition, building anything but C at this stage is a
waste of time.
In general, you can specify the languages to build by typing the
argument `LANGUAGES="list"', where list is one or more
words from the list `c', `c++', and `objective-c'. If
you have any additional GNU compilers as subdirectories of the GNU CC
source directory, you may also specify their names in this list.
Ignore any warnings you may see about ``statement not reached'' in
`insn-emit.c'; they are normal. Also, warnings about ``unknown
escape sequence'' are normal in `genopinit.c' and perhaps some
other files. Likewise, you should ignore warnings about ``constant is
so large that it is unsigned'' in `insn-emit.c' and
`insn-recog.c', a warning about a comparison always being zero
in `enquire.o', and warnings about shift counts exceeding type
widths in `cexp.y'. Any other compilation errors may represent bugs in
the port to your machine or operating system, and
should be investigated and reported (see Bugs).
Some compilers fail to compile GNU CC because they have bugs or limitations. For example, the Microsoft compiler is said to run out of macro space. Some Ultrix compilers run out of expression space; then you need to break up the statement where the problem happens.
make stage1
The files are moved into a subdirectory named `stage1'.
Once installation is complete, you may wish to delete these files
with rm -r stage1.
stage1' subdirectory
under the names `as', `ld' or whatever is appropriate. This
will enable the stage 1 compiler to find the proper tools in the
following stage.
Alternatively, you can do subsequent compilation using a value of the
PATH environment variable such that the necessary GNU tools come
before the standard system tools.
make CC="stage1/xgcc -Bstage1/" CFLAGS="-g -O2"
This is called making the stage 2 compiler.
The command shown above builds compilers for all the supported
languages. If you don't want them all, you can specify the languages to
build by typing the argument `LANGUAGES="list"'. list
should contain one or more words from the list `c', `c++',
`objective-c', and `proto'. Separate the words with spaces.
`proto' stands for the programs protoize and
unprotoize; they are not a separate language, but you use
LANGUAGES to enable or disable their installation.
If you are going to build the stage 3 compiler, then you might want to build only the C language in stage 2.
Once you have built the stage 2 compiler, if you are short of disk
space, you can delete the subdirectory `stage1'.
On a 68000 or 68020 system lacking floating point hardware,
unless you have selected a `tm.h' file that expects by default
that there is no such hardware, do this instead:
make CC="stage1/xgcc -Bstage1/" CFLAGS="-g -O2 -msoft-float"
stage2' subdirectory as you did in the
`stage1' subdirectory, then do this:
make stage2 make CC="stage2/xgcc -Bstage2/" CFLAGS="-g -O2"
This is called making the stage 3 compiler. Aside from the `-B'
option, the compiler options should be the same as when you made the
stage 2 compiler. But the LANGUAGES option need not be the
same. The command shown above builds compilers for all the supported
languages; if you don't want them all, you can specify the languages to
build by typing the argument `LANGUAGES="list"', as described
above.
If you do not have to install any additional GNU tools, you may use the command
make bootstrap LANGUAGES=language-list BOOT_CFLAGS=option-list
instead of making `stage1', `stage2', and performing
the two compiler builds.
On some systems, meaningful comparison of object files is impossible;
they always appear ``different.'' This is currently true on Solaris and
some systems that use ELF object file format. On some versions of Irix
on SGI machines and DEC Unix (OSF/1) on Alpha systems, you will not be
able to compare the files without specifying `-save-temps'; see the
description of individual systems above to see if you get comparison
failures. You may have similar problems on other systems.
Use this command to compare the files:
make compare
This will mention any object files that differ between stage 2 and stage 3. Any difference, no matter how innocuous, indicates that the stage 2 compiler has compiled GNU CC incorrectly, and is therefore a potentially serious bug which you should investigate and report (see Bugs).
If your system does not put time stamps in the object files, then this is a faster way to compare them (using the Bourne shell):
for file in *.o; do cmp $file stage2/$file done
If you have built the compiler with the `-mno-mips-tfile' option on
MIPS machines, you will not be able to compare the files.
make install'. Use the same value for CC,
CFLAGS and LANGUAGES that you used when compiling the
files that are being installed. One reason this is necessary is that
some versions of Make have bugs and recompile files gratuitously when
you do this step. If you use the same variable values, those files will
be recompiled properly.
For example, if you have built the stage 2 compiler, you can use the following command:
make install CC="stage2/xgcc -Bstage2/" CFLAGS="-g -O" LANGUAGES="list"
This copies the files `cc1', `cpp' and `libgcc.a' to
files `cc1', `cpp' and `libgcc.a' in the directory
`/usr/local/lib/gcc-lib/target/version', which is where
the compiler driver program looks for them. Here target is the
canonicalized form of target machine type specified when you ran
`configure', and version is the version number of GNU CC.
This naming scheme permits various versions and/or cross-compilers to
coexist. It also copies the executables for compilers for other
languages (e.g., `cc1plus' for C++) to the same directory.
This also copies the driver program `xgcc' into
`/usr/local/bin/gcc', so that it appears in typical execution
search paths. It also copies `gcc.1' into
`/usr/local/man/man1' and info pages into `/usr/local/info'.
On some systems, this command causes recompilation of some files. This
is usually due to bugs in make. You should either ignore this
problem, or use GNU Make.
Warning: there is a bug in alloca in the Sun library. To avoid this bug, be sure to install the executables of GNU CC that were compiled by GNU CC. (That is, the executables from stage 2 or 3, not stage 1.) They use alloca as a built-in function and never the one in the library.
(It is usually better to install GNU CC executables from stage 2 or 3, since they usually run faster than the ones compiled with some other compiler.)
The standard C++ runtime library for GNU CC is called `libstdc++'.
An obsolescent library `libg++' may also be available, but it's
necessary only for older software that hasn't been converted yet; if
you don't know whether you need `libg++' then you probably don't
need it.
Here's one way to build and install `libstdc++' for GNU CC:
gcc' obtains the GNU CC
that was just built.
libstdc++' distribution. For
example, the `libstdc++-2.8.0.tar.gz' distribution should be
compatible with GCC 2.8.0. GCC distributors normally distribute
`libstdc++' as well.
CXX' environment variable to `gcc' while running the
`libstdc++' distribution's `configure' command. Use the same
`configure' options that you used when you invoked GCC's
`configure' command.
make' to build the C++ runtime.
make install' to install the C++ runtime.
To summarize, after building and installing GNU CC, invoke the following shell commands in the topmost directory of the C++ library distribution. For configure-options, use the same options that you used to configure GNU CC.
$ CXX=gcc ./configure configure-options $ make $ make install
objc'. The GNU Objective-C
Runtime Library requires header files for the target's C library in
order to be compiled,and also requires the header files for the target's
thread library if you want thread support. See Cross-Compilers and Header Files, for
discussion about header files issues for cross-compilation.
When you run `configure', it picks the appropriate Objective-C
thread implementation file for the target platform. In some situations,
you may wish to choose a different back-end as some platforms support
multiple thread implementations or you may wish to disable thread
support completely. You do this by specifying a value for the
OBJC_THREAD_FILE makefile variable on the command line when you
run make, for example:
make CC="stage2/xgcc -Bstage2/" CFLAGS="-g -O2" OBJC_THREAD_FILE=thr-single
Below is a list of the currently available back-ends.
Using and Porting the GNU Compiler Collection (GCC)
Packaging copyright © 1988-2000 OAR Corporation Context copyright by each document's author. See Free Software Foundation for information.