P

lease read this document carefully before installing the GNU Compiler Collection on your machine.

- 1750a-*-*
- a29k
- a29k-*-bsd
- alpha*-*-*
- alpha*-dec-osf*
- alphaev5-cray-unicosmk*
- arc-*-elf
- arm-*-aout
- arm-*-elf
- arm*-*-linux-gnu
- arm-*-riscix
- avr
- c4x
- DOS
- dsp16xx
- elxsi-elxsi-bsd
- *-*-freebsd*
- h8300-hms
- hppa*-hp-hpux*
- hppa*-hp-hpux9
- hppa*-hp-hpux10
- hppa*-hp-hpux11
- i370-*-*
- *-*-linux-gnu
- i?86-*-linux*oldld
- i?86-*-linux*aout
- i?86-*-linux*
- i?86-*-sco
- i?86-*-sco3.2v4
- i?86-*-sco3.2v5*
- i?86-*-udk
- i?86-*-isc
- i?86-*-esix
- i?86-ibm-aix
- i?86-sequent-bsd
- i?86-sequent-ptx1* i?86-sequent-ptx2*, i?86-sequent-sysv3*
- i860-intel-osf*
- ia64-*-linux
- *-lynx-lynxos
- *-ibm-aix*
- m32r-*-elf
- m68000-hp-bsd
- m6811-elf
- m6812-elf
- m68k-altos
- m68k-apple-aux
- m68k-att-sysv
- m68k-bull-sysv
- m68k-crds-unos
- m68k-hp-hpux
- m68k-*-nextstep*
- m68k-ncr-*
- m68k-sun
- m68k-sun-sunos4.1.1
- m88k-*-svr3
- m88k-*-dgux
- m88k-tektronix-sysv3
- mips-*-*
- mips-dec-*
- mips-mips-bsd
- mips-mips-riscos*
- mips-sgi-irix4
- mips-sgi-irix5
- mips-sgi-irix6
- mips-sony-sysv
- ns32k-encore
- ns32k-*-genix
- ns32k-sequent
- ns32k-utek
- powerpc*-*-* powerpc-*-sysv4
- powerpc-*-darwin*
- powerpc-*-elf powerpc-*-sysv4
- powerpc-*-linux-gnu*
- powerpc-*-netbsd*
- powerpc-*-eabiaix
- powerpc-*-eabisim
- powerpc-*-eabi
- powerpcle-*-elf powerpcle-*-sysv4
- powerpcle-*-eabisim
- powerpcle-*-eabi
- powerpcle-*-winnt powerpcle-*-pe
- romp-*-aos romp-*-mach
- #s390-*-linux*
- #s390x-*-linux*
- *-*-solaris2*
- sparc-sun-solaris2*
- sparc-sun-solaris2.7
- sparc-sun-sunos4*
- sparc-unknown-linux-gnulibc1
- sparc-*-linux*
- sparc64-*-*
- sparcv9-*-solaris2*
- *-*-sysv*
- vax-dec-ultrix
- we32k-*-*
- xtensa-*-elf
- xtensa-*-linux*
- Microsoft Windows
- OS/2
- Older systems

- all ELF targets (SVR4, Solaris 2, etc.)

## 1750a-*-*

MIL-STD-1750A processors. This target is obsoleted in GCC 3.1.

The MIL-STD-1750A cross configuration produces output for `as1750`, an assembler/linker available under the GNU General Public License for the 1750A. `as1750` can be obtained at 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 `libgcc` (`libgcc` is not yet implemented for the 1750A.)

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

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

`Normal`
  The program code section.
`Static`
  The read/write (RAM) data section.
`Konst`
  The read-only (ROM) constants section.
`Init`
  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 GCC.

## a29k

AMD Am29k-family processors. These are normally used in embedded applications. This configuration corresponds to AMD's standard calling sequence and binary interface and is compatible with other 29k tools.

AMD has abandoned this processor. All existing a29k targets are obsoleted in GCC 3.1.

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.

## 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.

## 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.

Support for versions before `alpha*-dec-osf4` is obsoleted in GCC 3.1. (These are the versions which identify themselves as DEC OSF/1.)

In Digital Unix V4.0, virtual memory exhausted bootstrap failures may be fixed by configuring with `--with-gc=simple`, reconfiguring Kernel Virtual Memory and Swap parameters per the `/usr/sbin/sys_check` Tuning Suggestions, or applying the patch in http://gcc.gnu.org/ml/gcc/2002-08/msg00822.html.

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

       % CC=cc srcdir/configure [options] [target]

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

       % CC=gcc -Wa,-oldas srcdir/configure [options] [target]

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

The `--enable-threads` options isn't supported yet. A patch is in preparation for a future release.

GCC 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 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.

`make compare` may fail on old versions of DEC Unix 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.

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 `--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, 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 `-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.

## 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 `/opt/ctl/craylibs/craylibs`.

You absolutely 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 `--with-as` and `--with-ld` to `configure`, e.g.

        configure --with-as=/opt/ctl/bin/cam --with-ld=/opt/ctl/bin/cld \
          --enable-languages=c

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

## arc-*-elf

Argonaut ARC processor. This configuration is intended for embedded systems.

## 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 `a.out` format object modules.

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

## arm-*-elf

This configuration is intended for embedded systems.

## arm*-*-linux-gnu

We require GNU binutils 2.10 or newer.

## arm-*-riscix

The ARM2 or ARM3 processor running RISC iX, Acorn's port of BSD Unix. This configuration is obsoleted in GCC 3.1.

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 ftp://ftp.acorn.com/pub/riscix/as+xterm.tar.Z. To enable stabs debugging, pass `--with-gnu-as` to configure.

You will need to install GNU `sed` before you can run configure.

## avr

ATMEL AVR-family micro controllers. These are used in embedded applications. There are no standard Unix configurations. See "AVR Options" in the main manual for the list of supported MCU types.

Use `configure --target=avr --enable-languages="c"` to configure GCC.

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

- http://home.overta.ru/users/denisc
- http://www.amelek.gda.pl/avr

We strongly recommend using binutils 2.11 or newer.

The following error:

      Error: register required

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

## c4x

Texas Instruments TMS320C3x and TMS320C4x Floating Point Digital Signal Processors. These are used in embedded applications. There are no standard Unix configurations. See "TMS320C3x/C4x Options" in the main manual 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 `configure --target=c4x --enable-languages="c,c++"` to configure.

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

- http://www.elec.canterbury.ac.nz/c4x/

## CRIS

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

See "CRIS Options" in the main manual for a list of CRIS-specific options.

There are a few different CRIS targets:

`cris-axis-aout`
  Old target. Includes a multilib for the `elinux` a.out-based target. No multilibs for newer architecture variants.
`cris-axis-elf`
  Mainly for monolithic embedded systems. Includes a multilib for the `v10` core used in `ETRAX 100 LX`.
`cris-axis-linux-gnu`
  A GNU/Linux port for the CRIS architecture, currently targeting `ETRAX 100 LX` by default.

For `cris-axis-aout` and `cris-axis-elf` you need binutils 2.11 or newer. For `cris-axis-linux-gnu` you need binutils 2.12 or newer.

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

## DOS

Please have a look at our 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.

## dsp16xx

A port to the AT&T DSP1610 family of processors.

## *-*-freebsd*

The version of binutils installed in `/usr/bin` is known to work unless otherwise specified in any per-architecture notes. However, binutils 2.12.1 or greater 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 `/usr/bin`) and C++ EH failures were noted.

Support for FreeBSD 1 is obsoleted in GCC 3.1.

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 `-gstabs` instead of `-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, `--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, 4.4, 4.5-STABLE and 5-CURRENT.

In principle, `--enable-threads` is now compatible with `--enable-libgcj` on FreeBSD. However, it has only been built and tested on `i386-*-freebsd4.5` and `alpha-*-freebsd5.0`. The static library may be incorrectly built (symbols are missing at link time). There is a rare timing-based startup hang (probably involves an assupmtion about the thread library). Multi-threaded boehm-gc (required for libjava) exposes severe threaded signal-handling bugs on FreeBSD before 4.5-RELEASE. The alpha port may not fully bootstrap without some manual intervention: `gcjh` will crash with a floating-point exception while generating `java/lang/Double.h` (just copy the version built on `i386-*-freebsd*` and rerun the top-level `gmake` with no arguments and it should properly complete the bootstrap). Other CPU architectures supported by FreeBSD will require additional configuration tuning in, at the very least, both boehm-gc and libffi.

Shared `libgcc_s.so` is now built and installed by default.

## elxsi-elxsi-bsd

The Elxsi's C compiler has known limitations that prevent it from compiling GCC. Please contact mrs@wrs.com for more details.

Support for this processor is obsoleted in GCC 3.1.

## h8300-hms

Hitachi H8/300 series of processors.

Please have a look at our 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.

## hppa*-hp-hpux*

We 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. The HP assembler does not work with the `hppa64-hp-hpux11*` port.

Specifically, `-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 `--with-gnu-as` and `--with-as=...` options.

If you wish to use the pa-risc 2.0 architecture support with a 32-bit runtime, you must use either the HP assembler, gas/binutils 2.11 or newer, or a recent snapshot of gas.

More specific information to `hppa*-hp-hpux*` targets follows.

## 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 `CONFIG_SHELL` to `/bin/ksh` and `SHELL` to `/bin/ksh` in your environment.

## hppa*-hp-hpux10

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

- US, Canada, Asia-Pacific, and Latin-America
- Europe

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 `make bootstrap`. You should be able to continue by saying `make all` after getting the failure from `make bootstrap`.

## hppa*-hp-hpux11

GCC 3.0 and up support HP-UX 11. On 64-bit capable systems, there are two distinct ports. The `hppa2.0w-hp-hpux11*` port generates code for the 32-bit pa-risc runtime architecture. It uses the HP linker and is currently the default selected by config.guess. The optional `hppa64-hp-hpux11*` port generates 64-bit code for the pa-risc 2.0 architecture. It must be explicitly selected using the `--host=hppa64-hp-hpux11*` configure option. Different prefixes must be used if both ports are to be installed on the same system.

You must use GNU binutils 2.11 or above with the 32-bit port. Thread support is not currently implemented, so `--enable-threads` does not work. See:

- http://gcc.gnu.org/ml/gcc-prs/2002-01/msg00551.html
- http://gcc.gnu.org/ml/gcc-bugs/2002-01/msg00663.html.

GCC 2.95.x is not supported under HP-UX 11 and cannot be used to compile GCC 3.0 and up. Refer to binaries for information about obtaining precompiled GCC binaries for HP-UX.

GNU binutils 2.13 or later is recommended with the 64-bit port. The HP assembler is not supported. It is highly recommended that the GNU linker be used as well. Either binutils must be built prior to gcc, or a binary distribution of gcc or binutils must be obtained for the initial builds. When starting with a HP compiler, it is preferable to use the ANSI compiler as the bundled compiler only supports traditional C. Bootstrapping with the bundled compiler is tested infrequently and problems often arise because of the subtle differences in semantics between traditional and ISO C. There also have been problems reported with various binary distributions. This port still is undergoing significant development.

## i370-*-*

This port is very preliminary and has many known bugs. We hope to have a higher-quality port for this machine soon.

## *-*-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 `libstdc++`. The patch glibc-2.2.patch, that is to be applied in the GCC source tree, fixes the compatibility problems.

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.

## i?86-*-linux*oldld

Use this configuration to generate `a.out` binaries on Linux-based GNU systems if you do not have gas/binutils version 2.5.2 or later installed.

This configuration is obsoleted in GCC 3.1.

## i?86-*-linux*aout

Use this configuration to generate `a.out` binaries on Linux-based GNU systems. This configuration is being superseded. You must use gas/binutils version 2.5.2 or later.

## 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 www.bitwizard.nl.

## 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.

## i?86-*-sco3.2v4

Use this configuration for SCO release 3.2 version 4.

## 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 `-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:

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

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 `--with-gnu-as`. You must use a recent version of GNU binutils; versions past 2.9.1 seem to work well.

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

Look in `gcc/config/i386/sco5.h` (search for "messy") for additional OpenServer-specific flags.

Systems based on OpenServer before 5.0.4 (`uname -X` will tell you what you're running) require TLS597 from 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 `-fPIC` on `921215-1.c`, `931002-1.c`, `nestfunc-1.c`, and `gcov-1.c`. For 5.0.5, an updated linker that will cure this problem is available. You must install both ftp://ftp.sco.com/Supplements/rs505a/ and 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 `-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 `-fPIC`--try applying `sco_osr5_g77.patch` to your `libf2c` and rebuilding GCC. Affected faults, when analyzed in a debugger, will show a stack backtrace with a fault occurring in `rtld()` and the program running as `/usr/lib/ld.so.1`. This problem has been reported to SCO engineering and will hopefully be addressed in later releases.

## 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 `/udk/usr/ccs/bin/cc` file present.) It's very much like the `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:

        CC=/udk/usr/ccs/bin/cc /your/path/to/gcc/configure \
          --host=i686-pc-udk --target=i686-pc-udk --program-prefix=udk-

You should substitute `i686` in the above command with the appropriate processor for your host.

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

## i?86-*-isc

This configuration is obsoleted in GCC 3.1.

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, `sed` core dumps when building `deduced.h`. Use the version of `sed` from version 4.0.

## i?86-ibm-aix

This configuration is obsoleted in GCC 3.1.

You need to use GAS version 2.1 or later, and LD from GNU binutils version 2.2 or later.

## i?86-sequent-bsd

This configuration is obsoleted in GCC 3.1.

Go to the Berkeley universe before compiling.

## i?86-sequent-ptx1*, i?86-sequent-ptx2*, i?86-sequent-sysv3*

This configuration is obsoleted in GCC 3.1.

You must install GNU `sed` before running `configure`.

The `fixproto` shell script may trigger a bug in the system shell. If you encounter this problem, upgrade your operating system or use `bash` (the GNU shell) to run `fixproto`.

## i860-intel-osf*

All support for the i860 processor is obsoleted in GCC 3.1.

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 `va_arg` when you build GCC.

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

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

insert the line

    #if __PGC__

and after the lines

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

insert the line

    #endif /* __PGC__ */

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

## 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.

## *-lynx-lynxos

LynxOS 2.2 and earlier comes with GCC 1.x already installed as `/bin/gcc`. You should compile with this instead of `/bin/cc`. You can tell GCC to use the GNU assembler and linker, by specifying `--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 `a.out` format executables.

## *-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 `alloca` when building GCC generally are due to an incorrect definition of `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 must be invoked as `cc` (not `xlc`). Once `configure` has been informed of `xlc`, one needs to use `make distclean` to remove the configure cache files and ensure that `CC` environment variable does not provide a definition that will confuse `configure`. If this error occurs during stage2 or later, then the problem most likely is the version of Make (see above).

The GNU Assembler incorrectly reports that it supports WEAK symbols on AIX which causes GCC to try to utilize weak symbol functionality which is not really supported on the platform. The native `as` and `ld` still are recommended. The native AIX tools do interoperate with GCC.

Building `libstdc++.a` requires a fix for a AIX Assembler bug APAR IY26685 (AIX 4.3) or APAR IY25528 (AIX 5.1).

`libstdc++` in GCC 3.2 increments the major version number of the shared object and GCC installation places the `libstdc++.a` shared library in a common location which will overwrite the GCC 3.1 version of the shared library. Applications either need to be re-linked against the new shared library or the GCC 3.1 version of the `libstdc++` shared object needs to be available to the AIX runtime loader. The GCC 3.1 `libstdc++.so.4` shared object can be installed for runtime dynamic loading using the following steps to set the `F_LOADONLY` flag in the shared object for each multilib `libstdc++.a` installed:

Extract the shared object from each the GCC 3.1 `libstdc++.a` archive:

       % ar -x libstdc++.a libstdc++.so.4

Enable the `F_LOADONLY` flag so that the shared object will be available for runtime dynamic loading, but not linking:

       % strip -e libstdc++.so.4

Archive the runtime-only shared object in the GCC 3.2 `libstdc++.a` archive:

       % ar -q libstdc++.a libstdc++.so.4

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.

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 `-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 `-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 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 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 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., `.` vs `,` 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 `LANG` environment variable to `C` or `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 `-mcpu=cpu_type` switch and using the configure option `--with-cpu-cpu_type`.

## m32r-*-elf

Mitsubishi M32R processor. This configuration is intended for embedded systems.

## m68000-hp-bsd

HP 9000 series 200 running BSD. Note that the C compiler that comes with this system cannot compile GCC; contact law@cygnus.com to get binaries of GCC for bootstrapping.

## m6811-elf

Motorola 68HC11 family micro controllers. These are used in embedded applications. There are no standard Unix configurations.

## m6812-elf

Motorola 68HC12 family micro controllers. These are used in embedded applications. There are no standard Unix configurations.

## m68k-altos

Altos 3068. This configuration is obsoleted in GCC 3.1.

You must use the GNU assembler, linker and debugger. Also, you must fix a kernel bug.

## m68k-apple-aux

Apple Macintosh running A/UX. This configuration is obsoleted in GCC 3.1.

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 `--with-gnu-as` and `--with-gnu-ld` options to `configure`.

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

## 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 ftp://archive.cis.ohio-state.edu/pub/att7300/.

## m68k-bull-sysv

Bull DPX/2 series 200 and 300 with BOS-2.00.45 up to BOS-2.01. This configuration is obsoleted in GCC 3.1.

GCC 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 stabs-in-COFF encapsulation by providing `--with-gnu-as --stabs`. For any problem with the native assembler or for availability of the DPX/2 port of GAS, contact F.Pierresteguy@frcl.bull.fr.

## m68k-crds-unos

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 GCC, 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 GCC to function, either change all references to `-lc` in `gcc.c` to `-lunos` or link `/lib/libc.a` to `/lib/libunos.a`.

When compiling GCC 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 GCC. This bug manifests itself during the first stage of compilation, while building `libgcc2.a`:

    _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

A patched version of the assembler is available as the file 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:

> 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.

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 `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 `fixproto`. This bug will cause the fixproto program to report an error of the form:

    ./fixproto: sh internal 1K buffer overflow

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

    #!/bin/ksh

## m68k-*-nextstep*

These configurations are obsoleted in GCC 3.1.

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 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:

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

The reason for this is the fact that NeXT's assembler for these versions of the operating system does not support the `.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 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 prefix you specified in the configuration process of GCC for this sequence to work.

      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

## m68k-ncr-*

On the Tower models 4n0 and 6n0, by default a process is not allowed to have more than one megabyte of memory. GCC cannot compile itself (or many other programs) with `-O` in that much memory.

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

    MAXUMEM = 4096

## 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.

## m68k-sun-sunos4.1.1

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

## m88k-*-svr3

Motorola m88k running the AT&T/Unisoft/Motorola V.3 reference port. These configurations are obsoleted in GCC 3.1.

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.

## m88k-*-dgux

Motorola m88k running DG/UX. These configurations are obsoleted in GCC 3.1.

To build 88open BCS native or cross compilers on DG/UX, specify the configuration name as `m88k-*-dguxbcs` and build in the 88open BCS software development environment. To build ELF native or cross compilers on DG/UX, specify `m88k-*-dgux` and build in the DG/UX ELF development environment. You set the software development environment by issuing `sde-target` command and specifying either `m88kbcs` or `m88kdguxelf` as the operand.

If you do not specify a configuration name, `configure` guesses the configuration based on the current software development environment.

## m88k-tektronix-sysv3

Tektronix XD88 running UTekV 3.2e. These configurations are obsoleted in GCC 3.1.

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-*-*

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 `-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 `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 `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 `-non_shared` to the linker unless you pass an explicit `-shared` or `-call_shared` switch.

## mips-mips-bsd

MIPS machines running the MIPS operating system in BSD mode. These configurations are obsoleted in GCC 3.1.

It's possible that some old versions of the system lack the functions `memcpy`, `memmove`, `memcmp`, and `memset`. If your system lacks these, you must remove or undo the definition of `TARGET_MEM_FUNCTIONS` in `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 `-Wf,-XNg1500` option. 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-dec-*

These configurations are obsoleted in GCC 3.1.

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 `alpha*-dec`.) To configure GCC for these platforms use the following configurations:

`mips-dec-ultrix`
  Ultrix configuration.
`mips-dec-osf1`
  DEC's version of OSF/1.
`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.

If you use the MIPS C compiler to bootstrap, it may be necessary to increase its table size for switch statements with the `-Wf,-XNg1500` option. 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*

These configurations are obsoleted in GCC 3.1.

If you use the MIPS C compiler to bootstrap, it may be necessary to increase its table size for switch statements with the `-Wf,-XNg1500` option. 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.

## mips-sgi-irix4

This configuration is obsoleted in GCC 3.1.

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 `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 GCC itself was miscompiled as a result.

You may get the following warning on IRIX 4 platforms, it can be safely ignored.

      warning: foo.o does not have gp tables for all its sections.

## 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 http://www.sgi.com/developers/devtools/apis/ido.html.

`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.

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

To enable debugging under IRIX 5, you must use GNU `as` 2.11.2 or later, and use the `--with-gnu-as` configure option when configuring GCC. GNU `as` is distributed as part of the binutils package. When using release 2.11.2, you need to apply a patch 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 `cc1` over and over again. This happens on `mips-sgi-irix5.2`, and possibly other platforms. It has been reported that this is a known bug in the `make` shipped with IRIX 5.2. We recommend you use GNU `make` instead of the vendor supplied `make` program; however, you may have success with `smake` on IRIX 5.2 if you do not have GNU `make` available.

## mips-sgi-irix6

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

    test.o: ELF N32 MSB ...

If you see:

    test.o: ELF 32-bit MSB ...

or

    test.o: ELF 64-bit MSB ...

then your version of `cc` uses the O32 or N64 ABI by default. You should set the environment variable `CC` to `cc -n32` before configuring GCC.

If you want the resulting `gcc` to run on old 32-bit systems with the MIPS R4400 CPU, you need to ensure that only code for the mips3 instruction set architecture (ISA) is generated. While GCC 3.x does this correctly, both GCC 2.95 and SGI's MIPSpro `cc` may change the ISA depending on the machine where GCC is built. Using one of them as the bootstrap compiler may result in mips4 code, which won't run at all on mips3-only systems. For the test program above, you should see:

    test.o: ELF N32 MSB mips-3 ...

If you get:

    test.o: ELF N32 MSB mips-4 ...

instead, you should set the environment variable `CC` to `cc -n32 -mips3` or `gcc -mips3` respectively 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 `--disable-multilib` so GCC doesn't try to use them. Look for `/usr/lib64/libc.so.1` to see if you have the 64-bit libraries installed.

You must not use GNU `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 `mips-sgi-irix6` configurations. It is possible to create a GCC with O32 ABI only support by configuring it for the `mips-sgi-irix5` target and using a patched GNU `as` 2.11.2 as documented in the `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 `--enable-threads` option doesn't currently work, a patch is in preparation for a future release. The `--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 `libgcj` is known not to build despite this, running into an internal error of the native `ld`. A sure fix is to increase this limit (`ncargs`) to its maximum of 262144 bytes. If you have root access, you can use the `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 `inet_ntoa`, `inet_lnaof`, `inet_netof`, `inet_makeaddr`, and `semctl`. Until the bug is fixed, GCC contains workarounds for the known affected functions.

See http://freeware.sgi.com/ for more information about using GCC on IRIX platforms.

## mips-sony-sysv

Sony MIPS NEWS. This configuration is obsoleted in GCC 3.1.

This works in NEWSOS 5.0.1, but not in 5.0.2 (which uses ELF instead of COFF). In particular, the linker does not like the code generated by GCC when shared libraries are linked in.

## ns32k-encore

This configuration is obsoleted in GCC 3.1.

Encore ns32000 system. Encore systems are supported only under BSD.

## ns32k-*-genix

National Semiconductor ns32000 system. This configuration is obsoleted in GCC 3.1.

Genix has bugs in `alloca` and `malloc`; you must get the compiled versions of these from GNU Emacs.

## ns32k-sequent

This configuration is obsoleted in GCC 3.1.

Go to the Berkeley universe before compiling.

## ns32k-utek

UTEK ns32000 system ("merlin"). This configuration is obsoleted in GCC 3.1.

The C compiler that comes with this system cannot compile GCC; contact `tektronix!reed!mason` to get binaries of GCC for bootstrapping.

## powerpc-*-*

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

## 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 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 `cctools` with tag `Apple-364`, build it, and install the assembler as `usr/bin/as`. See 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 `expr.c`. Set the stack to 800K or more, for instance by doing `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 `make bootstrap`, but to do it from the toplevel objdir you will need to say `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.

## powerpc-*-elf, powerpc-*-sysv4

PowerPC system in big endian mode, running System V.4.

## powerpc-*-linux-gnu*

You will need binutils 2.13.90.0.10 or newer for a working GCC.

## powerpc-*-netbsd*

PowerPC system in big endian mode running NetBSD. To build the documentation you will need Texinfo version 4.1 (NetBSD 1.5.1 included Texinfo version 3.12).

## powerpc-*-eabiaix

Embedded PowerPC system in big endian mode with `-mcall-aix` selected as the default.

## powerpc-*-eabisim

Embedded PowerPC system in big endian mode for use in running under the PSIM simulator.

## powerpc-*-eabi

Embedded PowerPC system in big endian mode.

## powerpcle-*-elf, powerpcle-*-sysv4

PowerPC system in little endian mode, running System V.4.

## powerpcle-*-eabisim

Embedded PowerPC system in little endian mode for use in running under the PSIM simulator.

## powerpcle-*-eabi

Embedded PowerPC system in little endian mode.

## powerpcle-*-winnt, powerpcle-*-pe

PowerPC system in little endian mode running Windows NT.

## romp-*-aos, romp-*-mach

These configurations are obsoleted in GCC 3.1.

We recommend you compile GCC with an earlier version of itself; if you compile GCC 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.

## s390-*-linux*

S/390 system running Linux for S/390.

## s390x-*-linux*

zSeries system (64-bit) running Linux for zSeries.

## *-*-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 binaries page for details.

The Solaris 2 `/bin/sh` will often fail to configure `libstdc++-v3`, `boehm-gc` or `libjava`. If you encounter this problem, set `CONFIG_SHELL` to `/bin/ksh` in your environment before running `configure`.

Solaris 2 comes with a number of optional OS packages. Some of these packages are needed to use GCC fully, namely `SUNWarc`, `SUNWbtool`, `SUNWesu`, `SUNWhea`, `SUNWlibm`, `SUNWsprot`, and `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 `pkginfo` command. To add an optional package, use the `pkgadd` command. For further details, see the Solaris 2 documentation.

Trying to use the linker and other tools in `/usr/ucb` to install GCC has been observed to cause trouble. For example, the linker may hang indefinitely. The fix is to remove `/usr/ucb` from your `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 `as`, Sun `ld`).

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

`g++` accepts such (invalid) constructs with the option `-fpermissive`; it will assume that any missing type is `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.

## sparc-sun-solaris2*

When GCC is configured to use binutils 2.11.2 or later the binaries produced are smaller than the ones produced using Sun's native tools; this difference is quite significant for binaries containing debugging information.

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

    /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 properly supports this; the `-m64` option enables 64-bit code generation. However, if all you want is code tuned for the UltraSPARC CPU, you should try the `-mtune=ultrasparc` option instead, which produces code that, unlike full 64-bit code, can still run on non-UltraSPARC machines.

When configuring on a Solaris 7 or later system that is running a kernel that supports only 32-bit binaries, one must configure with `--disable-multilib`, since we will not be able to build the 64-bit target libraries.

## 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:

- 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.
- Copy the original, unpatched Solaris 7 `/usr/ccs/bin/as` into `/usr/local/lib/gcc-lib/sparc-sun-solaris2.7/3.1/as`, adjusting the latter name to fit your local conventions and software version numbers.
- 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.

## sparc-sun-sunos4*

A bug in the SunOS 4 linker will cause it to crash when linking `-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 `genflags` or `genoutput` while building GCC. This is said to be due to a bug in `sh`. You can probably get around it by running `genflags` or `genoutput` manually and then retrying the `make`.

## sparc-unknown-linux-gnulibc1

It has been reported that you might need binutils 2.8.1.0.23 for this platform, too.

## 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 `sparc-*-*` targets.

## sparc64-*-*

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

## sparcv9-*-solaris2*

The following compiler flags must be specified in the configure step in order to bootstrap this target with the Sun compiler:

       % CC="cc -xildoff -xarch=v9" srcdir/configure [options] [target]

`-xildoff` turns off the incremental linker, and `-xarch=v9` specifies the v9 architecture to the Sun linker and assembler.

## *-*-sysv*

On System V release 3, you may get this error message while linking:

    ld fatal: failed to write symbol name something
     in strings table for file whatever

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 `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,

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

that too indicates a problem with disk space, ulimit, or `MAXUMEM`.

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

## vax-dec-ultrix

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

## we32k-*-*

These computers are also known as the 3b2, 3b5, 3b20 and other similar names. (However, the 3b1 is actually a 68000.) These configurations are obsoleted in GCC 3.1.

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 GCC. You can work around this by building `cpp` in GCC 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 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:

    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.

## xtensa-*-elf

This target is intended for embedded Xtensa systems using the `newlib` C library. It uses ELF but does not support shared objects. Designed-defined instructions specified via the Tensilica Instruction Extension (TIE) language are only supported through inline assembly.

The Xtensa configuration information must be specified prior to building GCC. The `gcc/config/xtensa/xtensa-config.h` header file contains the configuration information. If you created your own Xtensa configuration with the Xtensa Processor Generator, the downloaded files include a customized copy of this header file, which you can use to replace the default header file.

## xtensa-*-linux*

This target is for Xtensa systems running GNU/Linux. It supports ELF shared objects and the GNU C library (glibc). It also generates position-independent code (PIC) regardless of whether the `-fpic` or `-fPIC` options are used. In other respects, this target is the same as the `xtensa-*-elf` target.

## Microsoft Windows (32-bit)

A port of GCC 2.95.x is included with the Cygwin environment.

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

## 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 http://www.goof.com/pcg/os2/.

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

## 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.

We are planning to remove support for more older systems, starting in GCC 3.1. Each release will have a list of "obsoleted" systems. Support for these systems is still present in that release, but `configure` will fail unless the `--enable-obsolete` option is given. Unless a maintainer steps forward, support for these systems will be removed from the next release of GCC.

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 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 `old-releases` directory on the GCC mirror sites. Header bugs may generally be avoided using `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 `pub/binutils/old-releases` on 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.

## all ELF targets (SVR4, Solaris 2, etc.)

C++ support is significantly better on ELF targets if you use the GNU linker; duplicate copies of inlines, vtables and template instantiations will be discarded automatically.

Return to the GCC Installation page