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4.1: Configurations Supported by GNU CC

Here are the possible CPU types:

1750a, a29k, alpha, arm, cn, clipper, elxsi, h8300, hppa1.0, hppa1.1, i370, i386, i486, i860, i960, m68000, m68k, m88k, mips, ns32k, pyramid, romp, rs6000, sh, sparc, sparclite, sparc64, 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, 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.

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, amigados, aos, aout, bosx, bsd, clix, ctix, cxux, dgux, dynix, ebmon, elf, esix, freebsd, hms, genix, gnu, hiux, hpux, iris, irix, isc, linux, luna, lynxos, mach, minix, msdos, mvs, netbsd, newsos, nindy, ns, osf, osfrose, riscix, riscos, rtu, sco, solaris, sunos, sym, sysv, ultrix, unicos, uniplus, unos, vms, vxworks, 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.

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, 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 `local.md', `local.h', `local.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:

`1750a-*-*'
MIL-STD-1750A processors. This port is preliminary.

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

The Tektronix MIL-STD-1750A Assembler requires the file `m1750.inc', which is found in the directory `config/1750a'.

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

NREL
The program code section.
SREL
The read/write (RAM) data section.
KREL
The read-only (ROM) constants section.
IREL
Initialization section (code to copy KREL to SREL).

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

There is a problem with long argument lists to functions. The compiler aborts if the sum of space needed by all arguments exceeds 14 words. This is because the arguments are passed in registers (R0..R13) not on the stack, and there is a problem with passing further arguments (i.e. beyond those in R0..R13) via the stack.

If efficiency is less important than using long argument lists, you can change the definition of the FUNCTION_ARG macro in `config/1750/1750a.h' to always return zero. If you do that, GNU CC will pass all parameters on the stack.

`alpha-*-osf1'
Systems using processors that implement the DEC Alpha architecture and are running the OSF/1 operating system, for example the DEC Alpha AXP systems. (VMS on the Alpha is not currently supported by GNU CC.)

GNU CC writes a `.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 `/usr/include/stamp.h'. If you install a new version of OSF/1, 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.

make compare may fail on old versions of OSF/1 unless you add `-save-temps' to 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 stage1 and stage2 compilations. The option `-save-temps' forces a fixed name to be used for the assembler input file, instead of a randomly chosen name in `/tmp'. Do not add `-save-temps' unless the comparisons fail without that option. If you add `-save-temps', you will have to manually delete the `.i' and `.s' files after each series of compilations.

GNU CC 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 `--with-stabs' option of `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 `.align' directive is used. To work around this problem, GNU CC 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 `-O' is specified are different depending on whether or not `-g' is also specified.

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

`arm'
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 a.out format object modules.

You may need to make a variant of the file `arm.h' for your particular configuration.

`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.
`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 `a29k.h' for your particular configuration.

`a29k-*-bsd'
AMD Am29050 used in a system running a variant of BSD Unix.
`decstation-*'
DECstations can support three different personalities: Ultrix, DEC OSF/1, and OSF/rose. To configure GCC for these platforms use the following configurations:
`decstation-ultrix'
Ultrix configuration.
`decstation-osf1'
Dec's version of OSF/1.
`decstation-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.

The MIPS C compiler needs to be told to increase its table size for switch statements with the `-Wf,-XNg1500' option in order to compile `cp/parse.c'. If you use the `-O2' optimization option, you also need to use `-Olimit 3000'. Both of these options are automatically generated in the `Makefile' that the shell script `configure' builds. If you override the CC make variable and use the MIPS compilers, you may need to add `-Wf,-XNg1500 -Olimit 3000'.

`elxsi-elxsi-bsd'
The Elxsi's C compiler has known limitations that prevent it from compiling GNU C. Please contact mrs@cygnus.com for more details.
`h8300-*-*'
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.
`hppa*-*-*'
There are two variants of this CPU, called 1.0 and 1.1, which have different machine descriptions. You must use the right one for your machine. All 7nn machines and 8n7 machines use 1.1, while all other 8nn machines use 1.0.

The easiest way to handle this problem is to use `configure hpnnn' or `configure hpnnn-hpux', where nnn is the model number of the machine. Then `configure' will figure out if the machine is a 1.0 or 1.1. Use `uname -a' to find out the model number of your machine.

`-g' does not work on HP-UX, since that system uses a peculiar debugging format which GNU CC does not know about. However, `-g' will work if you also use GAS and GDB in conjunction with GCC. We highly recommend using GAS for all HP-PA configurations.

You should be using GAS-2.3 (or later) along with GDB-4.12 (or later). These can be retrieved from all the traditional GNU ftp archive sites.

Build GAS and install the resulting binary as:

/usr/local/lib/gcc-lib/configuration/gccversion/as

where configuration is the configuration name (perhaps `hpnnn-hpux') and gccversion is the GNU CC version number. Do this before starting the build process, otherwise you will get errors from the HPUX assembler while building `libgcc2.a'. The command

make install-dir

will create the necessary directory hierarchy so you can install GAS before building GCC.

To enable debugging, configure GNU CC with the `--with-gnu-as' option before building.

It has been reported that GNU CC produces invalid assembly code for 1.1 machines running HP-UX 8.02 when using the HP assembler. Typically the errors look like this:

as: bug.s @line#15 [err#1060]
  Argument 0 or 2 in FARG upper
         - lookahead = ARGW1=FR,RTNVAL=GR
as: foo.s @line#28 [err#1060]
  Argument 0 or 2 in FARG upper
         - lookahead = ARGW1=FR

You can check the version of HP-UX you are running by executing the command `uname -r'. If you are indeed running HP-UX 8.02 on a PA and using the HP assembler then configure GCC with "hpnnn-hpux8.02".

`i370-*-*'
This port is very preliminary and has many known bugs. We hope to have a higher-quality port for this machine soon.
`i386-*-linux'
Bash-1.12 has a bug that causes configure to fail. The symptom is that the c++ subdirectory, cp, is not configured. Bash-1.14 and later work fine.
`i386-*-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.
`i386-*-sco3.2.4'
Use this configuration for SCO release 3.2 version 4.
`i386-*-isc'
It may be good idea to link with GNU malloc instead of the malloc that comes with the system.
`i386-*-esix'
It may be good idea to link with GNU malloc instead of the malloc that comes with the system.
`i386-ibm-aix'
You need to use GAS version 2.1 or later, and and LD from GNU binutils version 2.2 or later.
`i386-sequent'
Go to the Berkeley universe before compiling. In addition, you probably need to create a file named `string.h' containing just one line: `#include <strings.h>'.
`i386-sun-sunos4'
You may find that you need another version of GNU CC to begin bootstrapping with, since the current version when built with the system's own compiler seems to get an infinite loop compiling part of `libgcc2.c'. GNU CC version 2 compiled with GNU CC (any version) seems not to have this problem.

See Sun Install, for information on installing GNU CC on Sun systems.

`i860-intel-osf1'
This is the Paragon. If you have version 1.0 of the operating system, see Installation Problems, for special things you need to do to compensate for peculiarities in the system.
`m68000-hp-bsd'
HP 9000 series 200 running BSD. Note that the C compiler that comes with this system cannot compile GNU CC; contact law@cs.utah.edu to get binaries of GNU CC for bootstrapping.
`m68k-altos'
Altos 3068. You must use the GNU assembler, linker and debugger. Also, you must fix a kernel bug. Details in the file `README.ALTOS'.
`m68k-att-sysv'
AT&T 3b1, a.k.a. 7300 PC. Special procedures are needed to compile GNU CC with this machine's standard C compiler, due to bugs in that compiler. You can bootstrap it more easily with previous versions of GNU CC if you have them.

Installing GNU CC on the 3b1 is difficult if you do not already have GNU CC running, due to bugs in the installed C compiler. However, the following procedure might work. We are unable to test it.

  1. Comment out the `#include "config.h"' line on line 37 of `cccp.c' and do `make cpp'. This makes a preliminary version of GNU cpp.
  2. Save the old `/lib/cpp' and copy the preliminary GNU cpp to that file name.
  3. Undo your change in `cccp.c', or reinstall the original version, and do `make cpp' again.
  4. Copy this final version of GNU cpp into `/lib/cpp'.
  5. Replace every occurrence of obstack_free in the file `tree.c' with _obstack_free.
  6. Run make to get the first-stage GNU CC.
  7. Reinstall the original version of `/lib/cpp'.
  8. Now you can compile GNU CC with itself and install it in the normal fashion.
`m68k-bull-sysv'
Bull DPX/2 series 200 and 300 with BOS-2.00.45 up to BOS-2.01. GNU CC works either with native assembler or GNU assembler. You can use GNU assembler with native coff generation by providing `--with-gnu-as' to the configure script or use GNU assembler with dbx-in-coff encapsulation by providing `--with-gnu-as --stabs'. For any problem with native assembler or for availability of the DPX/2 port of GAS, contact F.Pierresteguy@frcl.bull.fr.
`m68k-crds-unox'
Use `configure unos' for building on Unos.

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

#!/bin/sh
casm $*

The default Unos library is named `libunos.a' instead of `libc.a'. To allow GNU CC to function, either change all references to `-lc' in `gcc.c' to `-lunos' or link `/lib/libc.a' to `/lib/libunos.a'.

When compiling GNU CC with the standard compiler, to overcome bugs in the support of alloca, do not use `-O' when making stage 2. Then use the stage 2 compiler with `-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 ALLOCA in `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 `cc1' fails, try putting the object files into a library and linking from that library.

`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 GNU CC. To fix it, get patch PHCO_0800 from HP.

In addition, if you wish to use gas `--with-gnu-as' 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.

`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.

See Sun Install, for information on installing GNU CC on Sun systems.

`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 GNU CC for bootstrapping if you have one.

`m88k-*-dgux'
Motorola m88k running DG/UX. To build native or cross compilers on DG/UX, you must first change to the 88open BCS software development environment. This is done by issuing this command:
eval `sde-target m88kbcs`
`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.
`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 memcpy, memcmp, and memset. If your system lacks these, you must remove or undo the definition of TARGET_MEM_FUNCTIONS in `mips-bsd.h'.

The MIPS C compiler needs to be told to increase its table size for switch statements with the `-Wf,-XNg1500' option in order to compile `cp/parse.c'. If you use the `-O2' optimization option, you also need to use `-Olimit 3000'. Both of these options are automatically generated in the `Makefile' that the shell script `configure' builds. If you override the CC make variable and use the MIPS compilers, you may need to add `-Wf,-XNg1500 -Olimit 3000'.

`mips-mips-riscos*'
The MIPS C compiler needs to be told to increase its table size for switch statements with the `-Wf,-XNg1500' option in order to compile `cp/parse.c'. If you use the `-O2' optimization option, you also need to use `-Olimit 3000'. Both of these options are automatically generated in the `Makefile' that the shell script `configure' builds. If you override the CC make variable and use the MIPS compilers, you may need to add `-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:

`mips-mips-riscosrev'
Default configuration for RISC-OS, revision rev.
`mips-mips-riscosrevbsd'
BSD 4.3 configuration for RISC-OS, revision rev.
`mips-mips-riscosrevsysv4'
System V.4 configuration for RISC-OS, revision rev.
`mips-mips-riscosrevsysv'
System V.3 configuration for RISC-OS, revision rev.

The revision 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 (see Installation Problems, for more details).

`mips-sgi-*'
Silicon Graphics MIPS machines running IRIX. In order to compile GCC on an SGI 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.

make compare may fail on version 5 of IRIX unless you add `-save-temps' to 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 stage1 and stage2 compilations. The option `-save-temps' forces a fixed name to be used for the assembler input file, instead of a randomly chosen name in `/tmp'. Do not add `-save-temps' unless the comparisons fail without that option. If you do you `-save-temps', you will have to manually delete the `.i' and `.s' files after each series of compilations.

The MIPS C compiler needs to be told to increase its table size for switch statements with the `-Wf,-XNg1500' option in order to compile `cp/parse.c'. If you use the `-O2' optimization option, you also need to use `-Olimit 3000'. Both of these options are automatically generated in the `Makefile' that the shell script `configure' builds. If you override the CC make variable and use the MIPS compilers, you may need to add `-Wf,-XNg1500 -Olimit 3000'.

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 `mips-sgi-irix4loser'. This configuration inhibits assembler optimization.

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

The `-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 `-noasmopt', it may still be due to assembler reordering---perhaps GNU CC itself was miscompiled as a result.

See the file `README.IRIX5' for information on how to make debugging work.

`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.
`ns32k-encore'
Encore ns32000 system. Encore systems are supported only under BSD.
`ns32k-*-genix'
National Semiconductor ns32000 system. Genix has bugs in alloca and malloc; you must get the compiled versions of these from GNU Emacs.
`ns32k-sequent'
Go to the Berkeley universe before compiling. In addition, you probably need to create a file named `string.h' containing just one line: `#include <strings.h>'.
`ns32k-utek'
UTEK ns32000 system (``merlin''). The C compiler that comes with this system cannot compile GNU CC; contact `tektronix!reed!mason' to get binaries of GNU CC for bootstrapping.
`romp-*-aos'
`romp-*-mach'
The only operating systems supported for the IBM RT PC are AOS and MACH. GNU CC does not support AIX running on the RT. We recommend you compile GNU CC with an earlier version of itself; if you compile GNU CC with 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.
`rs6000-*-aix'
If you are running AIX version 3.2.5 and have XLC version 1.3.0.0, you must obtain XLC 1.3.0.2 by requesting PTF 421749 from IBM. If you are using an older version of AIX you may have an old version of the IBM assembler, which cannot correctly handle debugging directives. See the file `README.RS6000' for more details.

The PowerPC and POWER2 architectures are now supported, but have not been very extensively tested due to lack of appropriate systems. Only AIX is supported on the PowerPC. GNU CC does not yet support the 64-bit PowerPC instructions.

Objective C does not work on this architecture.

AIX on the RS/6000 provides support (NLS) for environments outside of the United States. Compilers and assemblers use NLS to support locale-specific representations of various objects including floating-point numbers ("." vs "," for separating decimal fractions). There have been problems reported where the library linked with GNU CC does not produce the same floating-point formats that the assembler accepts. If you have this problem, set the LANG environment variable to "C" or "En_US".

`vax-dec-ultrix'
Don't try compiling with Vax C (vcc). It produces incorrect code in some cases (for example, when alloca is used).

Meanwhile, compiling `cp/parse.c' with pcc does not work because of an internal table size limitation in that compiler. To avoid this problem, compile just the GNU C compiler first, and use it to recompile building all the languages that you want to run.

`sparc-sun-*'
See Sun Install, for information on installing GNU CC on Sun systems.
`vax-dec-vms'
See VMS Install, for details on how to install GNU CC on VMS.
`we32k-*-*'
These computers are also known as the 3b2, 3b5, 3b20 and other similar names. (However, the 3b1 is actually a 68000; see Configurations.)

Don't use `-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 `stmt.c' in GNU CC. You can work around this by building `cpp' in GNU CC first, then use that instead of the system's preprocessor with the system's C compiler to compile `stmt.c'. Here is how:

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

The system's compiler produces bad code for some of the GNU CC 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:

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

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