Note most of this information is out of date and superseded by the previous chapters of this manual. It is provided for historical reference only, because of a lack of volunteers to merge it into the main manual.
Here is the procedure for installing GNU CC on a GNU or Unix system. See VMS Install, for VMS systems.
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.
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 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.
1750a, a29k, alpha, arm, avr, cn, clipper, dsp16xx, elxsi, fr30, h8300, hppa1.0, hppa1.1, i370, i386, i486, i586, i686, i786, i860, i960, ip2k, m32r, m68000, m68k, m6811, m6812, m88k, mcore, mips, mipsel, mips64, mips64el, mn10200, mn10300, ns32k, pdp11, powerpc, powerpcle, romp, rs6000, sh, sparc, sparclite, sparc64, v850, vax, we32k.
Here are the recognized company names. As you can see, customary abbreviations are used rather than the longer official names.
acorn, alliant, altos, apollo, apple, att, bull, cbm, convergent, convex, crds, dec, dg, dolphin, elxsi, encore, harris, hitachi, hp, ibm, intergraph, isi, mips, motorola, ncr, next, ns, omron, plexus, sequent, sgi, sony, sun, tti, unicom, wrs.
The company name is meaningful only to disambiguate when the rest of the information supplied is insufficient. You can omit it, writing just cpu-system, if it is not needed. For example, vax-ultrix4.2 is equivalent to vax-dec-ultrix4.2.
Here is a list of system types:
386bsd, aix, acis, amigaos, aos, aout, aux, bosx, bsd, clix, coff, ctix, cxux, dgux, dynix, ebmon, ecoff, elf, esix, freebsd, hms, genix, gnu, linux, linux-gnu, hiux, hpux, iris, irix, isc, luna, lynxos, mach, minix, msdos, mvs, netbsd, newsos, nindy, ns, osf, osfrose, ptx, riscix, riscos, rtu, sco, sim, solaris, sunos, sym, sysv, udi, ultrix, unicos, uniplus, unos, vms, vsta, vxworks, winnt, xenix.
You can omit the system type; then configure guesses the operating system from the CPU and company.
You can add a version number to the system type; this may or may not make a difference. For example, you can write bsd4.3 or bsd4.4 to distinguish versions of BSD. In practice, the version number is most needed for sysv3 and sysv4, which are often treated differently.
linux-gnu is the canonical name for the GNU/Linux target; however GNU CC will also accept linux. The version of the kernel in use is not relevant on these systems. A suffix such as libc1 or aout distinguishes major versions of the C library; all of the suffixed versions are obsolete.
If you specify an impossible combination such as i860-dg-vms, then you may get an error message from configure, or it may ignore part of the information and do the best it can with the rest. configure always prints the canonical name for the alternative that it used. GNU CC does not support all possible alternatives.
Often a particular model of machine has a name. Many machine names are recognized as aliases for CPU/company combinations. Thus, the machine name sun3, mentioned above, is an alias for m68k-sun. Sometimes we accept a company name as a machine name, when the name is popularly used for a particular machine. Here is a table of the known machine names:
3300, 3b1, 3bn, 7300, altos3068, altos, apollo68, att-7300, balance, convex-cn, crds, decstation-3100, decstation, delta, encore, fx2800, gmicro, hp7nn, hp8nn, hp9k2nn, hp9k3nn, hp9k7nn, hp9k8nn, iris4d, iris, isi68, m3230, magnum, merlin, miniframe, mmax, news-3600, news800, news, next, pbd, pc532, pmax, powerpc, powerpcle, ps2, risc-news, rtpc, sun2, sun386i, sun386, sun3, sun4, symmetry, tower-32, tower.
Remember that a machine name specifies both the cpu type and the company name. If you want to install your own homemade configuration files, you can use local as the company name to access them. If you use configuration cpu-local, the configuration name without the cpu prefix is used to form the configuration file names.
Thus, if you specify m68k-local, configuration uses files m68k.md, local.h, m68k.c, xm-local.h, t-local, and x-local, all in the directory config/m68k.
Here is a list of configurations that have special treatment or special things you must know:
Since GNU CC generates assembler code, you probably need a cross-assembler that GNU CC 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.
To compile and run a program using a cross-compiler involves several steps:
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 GNU CC. This requires a suitable cross-assembler and cross-linker. For some targets, the GNU assembler and linker are available.
To build GNU CC as a cross-compiler, you start out by running configure. Use the --target=target to specify the target type. If configure was unable to correctly identify the system you are running on, also specify the --build=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 configure can correctly identify:
./configure --target=m68k-hp-bsd4.3
If you have a cross-assembler and cross-linker available, you should install them now. Put them in the directory /usr/local/target/bin. Here is a table of the tools you should put in this directory:
The installation of GNU CC 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 --host and --target options that you use for configuring GNU CC, then build and install them. They install their executables automatically into the proper directory. Alas, they do not support all the targets that GNU CC supports.
If you want to install libraries to use with the cross-compiler, such as a standard C library, put them in the directory /usr/local/target/lib; installation of GNU CC copies all the files in that subdirectory into the proper place for GNU CC to find them and link with them. Here's an example of copying some libraries from a target machine:
ftp target-machine
lcd /usr/local/target/lib
cd /lib
get libc.a
cd /usr/lib
get libg.a
get libm.a
quit
The precise set of libraries you'll need, and their locations on the target machine, vary depending on its operating system.
Many targets require “start files” such as crt0.o and
crtn.o which are linked into each executable; these too should be
placed in /usr/local/target/lib. There may be several
alternatives for crt0.o, for use with profiling or other
compilation options. Check your target's definition of
STARTFILE_SPEC to find out what start files it uses.
Here's an example of copying these files from a target machine:
ftp target-machine
lcd /usr/local/target/lib
prompt
cd /lib
mget *crt*.o
cd /usr/lib
mget *crt*.o
quit
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 GNU CC (and those of your program). However, if you intend to link your program with a standard C library such as 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 /usr/local/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 libgcc.a. (These are the parts that can be compiled with GNU CC.) 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:
(cd /usr/include; tar cf - .) > tarfile
Then, on the host machine, do this:
ftp target-machine
lcd /usr/local/target/include
get tarfile
quit
tar xf tarfile
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 GNU CC 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 GNU CC 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 make install, as usual.
To install the gcc command so you can use the compiler easily, in the same manner as you use the VMS C compiler, you must install the VMS CLD file for GNU CC as follows:
$ assign /system /translation=concealed -
disk:[gcc.] gnu_cc
$ assign /system /translation=concealed -
disk:[gcc.include.] gnu_cc_include
with the appropriate disk and directory names. These commands can be placed in your system startup file so they will be executed whenever the machine is rebooted. You may, if you choose, do this via the GCC_INSTALL.COM script in the [GCC] directory.
$ set command /table=sys$common:[syslib]dcltables -
/output=sys$common:[syslib]dcltables gnu_cc:[000000]gcc
$ install replace sys$common:[syslib]dcltables
$ library/help sys$library:helplib.hlb gcc.hlp
Now you can invoke the compiler with a command like gcc /verbose file.c, which is equivalent to the command gcc -v -c file.c in Unix.
If you wish to use GNU C++ you must first install GNU CC, and then perform the following steps:
$ assign /system /translation=concealed -
disk:[gcc.gxx_include.] gnu_gxx_include
with the appropriate disk and directory name. If you are going to be using a C++ runtime library, this is where its install procedure will install its header files.
The GNU C++ compiler can be invoked with a command like gcc /plus /verbose file.cc, which is equivalent to the command g++ -v -c file.cc in Unix.
We try to put corresponding binaries and sources on the VMS distribution tape. But sometimes the binaries will be from an older version than the sources, because we don't always have time to update them. (Use the /version option to determine the version number of the binaries and compare it with the source file version.c to tell whether this is so.) In this case, you should use the binaries you get to recompile the sources. If you must recompile, here is how:
$ @vmsconfig.com
$ assign /system /translation=concealed -
disk:[bison.] gnu_bison
You may, if you choose, use the INSTALL_BISON.COM script in the [BISON] directory.
$ set command /table=sys$common:[syslib]dcltables -
/output=sys$common:[syslib]dcltables -
gnu_bison:[000000]bison
$ install replace sys$common:[syslib]dcltables
To install the library, use the following commands:
$ library gnu_cc:[000000]gcclib/delete=(new,eprintf)
$ library gnu_cc:[000000]gcclib/delete=L_*
$ library libgcc2/extract=*/output=libgcc2.obj
$ library gnu_cc:[000000]gcclib libgcc2.obj
The first command simply removes old modules that will be replaced with
modules from libgcc2 under different module names. The modules
new and eprintf may not actually be present in your
gcclib.olb—if the VMS librarian complains about those modules
not being present, simply ignore the message and continue on with the
next command. The second command removes the modules that came from the
previous version of the library libgcc2.c.
Whenever you update the compiler on your system, you should also update the library with the above procedure.
$ assign dua0:[gcc.build_dir.]/translation=concealed, -
dua1:[gcc.source_dir.]/translation=concealed gcc_build
$ set default gcc_build:[000000]
where the directory dua1:[gcc.source_dir] contains the source code, and the directory dua0:[gcc.build_dir] is meant to contain all of the generated object files and executables. Once you have done this, you can proceed building GCC as described above. (Keep in mind that gcc_build is a rooted logical name, and thus the device names in each element of the search list must be an actual physical device name rather than another rooted logical name).
extern const variables will not have
the read-only bit set, and the linker will generate warning messages
about mismatched psect attributes for these variables. These warning
messages are merely a nuisance, and can safely be ignored.
CC, CFLAGS, and
LIBS. See comments in those files. However, you must
also have a working version of the GNU assembler (GNU as, aka GAS) as
it is used as the back end for GNU CC to produce binary object modules
and is not included in the GNU CC sources. GAS is also needed to
compile libgcc2 in order to build gcclib (see above);
make-l2.com expects to be able to find it operational in
gnu_cc:[000000]gnu-as.exe.
To use GNU CC on VMS, you need the VMS driver programs gcc.exe, gcc.com, and gcc.cld. They are distributed with the VMS binaries (gcc-vms) rather than the GNU CC sources. GAS is also included in gcc-vms, as is Bison.
Once you have successfully built GNU CC with VAX C, you should use the
resulting compiler to rebuild itself. Before doing this, be sure to
restore the CC, CFLAGS, and LIBS definitions in
make-cccp.com and make-cc1.com. The second generation
compiler will be able to take advantage of many optimizations that must
be suppressed when building with other compilers.
Under previous versions of GNU CC, the generated code would occasionally give strange results when linked with the sharable VAXCRTL library. Now this should work.
Even with this version, however, GNU CC itself should not be linked with
the sharable VAXCRTL. The version of qsort in
VAXCRTL has a bug (known to be present in VMS versions V4.6
through V5.5) which causes the compiler to fail.
The executables are generated by make-cc1.com and
make-cccp.com use the object library version of VAXCRTL in
order to make use of the qsort routine in gcclib.olb. If
you wish to link the compiler executables with the shareable image
version of VAXCRTL, you should edit the file tm.h (created
by vmsconfig.com) to define the macro QSORT_WORKAROUND.
QSORT_WORKAROUND is always defined when GNU CC is compiled with
VAX C, to avoid a problem in case gcclib.olb is not yet
available.