This is Info file gcc.info, produced by Makeinfo-1.55 from the input file gcc.texi. This file documents the use and the internals of the GNU compiler. Published by the Free Software Foundation 59 Temple Place - Suite 330 Boston, MA 02111-1307 USA Copyright (C) 1988, 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc. Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided also that the sections entitled "GNU General Public License," "Funding for Free Software," and "Protect Your Freedom--Fight `Look And Feel'" are included exactly as in the original, and provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Permission is granted to copy and distribute translations of this manual into another language, under the above conditions for modified versions, except that the sections entitled "GNU General Public License," "Funding for Free Software," and "Protect Your Freedom--Fight `Look And Feel'", and this permission notice, may be included in translations approved by the Free Software Foundation instead of in the original English.  File: gcc.info, Node: Configurations, Next: Other Dir, Up: Installation Configurations Supported by GNU CC ================================== Here are the possible CPU types: 1750a, a29k, alpha, arm, cN, clipper, dsp16xx, elxsi, h8300, hppa1.0, hppa1.1, i370, i386, i486, i586, i860, i960, m68000, m68k, m88k, mips, mipsel, mips64, mips64el, ns32k, powerpc, powerpcle, 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, wrs. The company name is meaningful only to disambiguate when the rest of the information supplied is insufficient. You can omit it, writing just `CPU-SYSTEM', if it is not needed. For example, `vax-ultrix4.2' is equivalent to `vax-dec-ultrix4.2'. Here is a list of system types: 386bsd, aix, acis, amigados, aos, aout, bosx, bsd, clix, coff, ctix, cxux, dgux, dynix, ebmon, ecoff, elf, esix, freebsd, hms, genix, gnu, gnu/linux, hiux, hpux, iris, irix, isc, luna, lynxos, mach, minix, msdos, mvs, netbsd, newsos, nindy, ns, osf, osfrose, ptx, riscix, riscos, rtu, sco, sim, solaris, sunos, sym, sysv, udi, ultrix, unicos, uniplus, unos, vms, vsta, vxworks, winnt, xenix. You can omit the system type; then `configure' guesses the operating system from the CPU and company. You can add a version number to the system type; this may or may not make a difference. For example, you can write `bsd4.3' or `bsd4.4' to distinguish versions of BSD. In practice, the version number is most needed for `sysv3' and `sysv4', which are often treated differently. If you specify an impossible combination such as `i860-dg-vms', then you may get an error message from `configure', or it may ignore part of the information and do the best it can with the rest. `configure' always prints the canonical name for the alternative that it used. GNU CC does not support all possible alternatives. Often a particular model of machine has a name. Many machine names are recognized as aliases for CPU/company combinations. Thus, the machine name `sun3', mentioned above, is an alias for `m68k-sun'. Sometimes we accept a company name as a machine name, when the name is popularly used for a particular machine. Here is a table of the known machine names: 3300, 3b1, 3bN, 7300, altos3068, altos, apollo68, att-7300, balance, convex-cN, crds, decstation-3100, decstation, delta, encore, fx2800, gmicro, hp7NN, hp8NN, hp9k2NN, hp9k3NN, hp9k7NN, hp9k8NN, iris4d, iris, isi68, m3230, magnum, merlin, miniframe, mmax, news-3600, news800, news, next, pbd, pc532, pmax, powerpc, powerpcle, ps2, risc-news, rtpc, sun2, sun386i, sun386, sun3, sun4, symmetry, tower-32, tower. Remember that a machine name specifies both the cpu type and the company name. If you want to install your own homemade configuration files, you can use `local' as the company name to access them. If you use configuration `CPU-local', the configuration name without the cpu prefix is used to form the configuration file names. Thus, if you specify `m68k-local', configuration uses files `m68k.md', `local.h', `m68k.c', `xm-local.h', `t-local', and `x-local', all in the directory `config/m68k'. Here is a list of configurations that have special treatment or special things you must know: `1750a-*-*' MIL-STD-1750A processors. Starting with GCC 2.6.1, the MIL-STD-1750A cross configuration no longer supports the Tektronix Assembler, but instead produces output for `as1750', an assembler/linker available under the GNU Public License for the 1750A. Contact *kellogg@space.otn.dasa.de* for more details on obtaining `as1750'. 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 `config/1750a'. GNU CC 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 GNU CC. `alpha-*-osf1' Systems using processors that implement the DEC Alpha architecture and are running the DEC Unix (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 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. 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. `dsp16xx' A port to the AT&T DSP1610 family of processors. `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 several variants of the HP-PA processor which run a variety of operating systems. GNU CC must be configured to use the correct processor type and operating system, or GNU CC will not function correctly. The easiest way to handle this problem is to *not* specify a target when configuring GNU CC, the `configure' script will try to automatically determine the right processor type and operating system. `-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-2.6 (or later) along with GDB-4.16 (or later). These can be retrieved from all the traditional GNU ftp archive sites. GAS will need to be installed into a directory before `/bin', `/usr/bin', and `/usr/ccs/bin' in your search path. You should install GAS before you build GNU CC. To enable debugging, you must configure GNU CC with the `--with-gnu-as' option before building. `i370-*-*' This port is very preliminary and has many known bugs. We hope to have a higher-quality port for this machine soon. `i386-*-linuxoldld' 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 is an obsolete configuration. `i386-*-linuxaout' 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. `i386-*-linux' Use this configuration to generate ELF binaries on Linux-based GNU systems. You must use gas/binutils version 2.5.2 or later. `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-*-sco3.2v4' Use this configuration for SCO release 3.2 version 4. `i386-*-isc' 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. `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-bsd' Go to the Berkeley universe before compiling. In addition, you probably need to create a file named `string.h' containing just one line: `#include '. `i386-sequent-ptx1*' Sequent DYNIX/ptx 1.x. `i386-sequent-ptx2*' Sequent DYNIX/ptx 2.x. `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 *Note Sun Install::, for information on installing GNU CC on Sun systems. `i[345]86-*-winnt3.5' This version requires a GAS that has not let been released. Until it is, you can get a prebuilt binary version via anonymous ftp from `cs.washington.edu:pub/gnat' or `cs.nyu.edu:pub/gnat'. You must also use the Microsoft header files from the Windows NT 3.5 SDK. Find these on the CDROM in the `/mstools/h' directory dated 9/4/94. You must use a fixed version of Microsoft linker made especially for NT 3.5, which is also is available on the NT 3.5 SDK CDROM. If you do not have this linker, can you also use the linker from Visual C/C++ 1.0 or 2.0. Installing GNU CC for NT builds a wrapper linker, called `ld.exe', which mimics the behaviour of Unix `ld' in the specification of libraries (`-L' and `-l'). `ld.exe' looks for both Unix and Microsoft named libraries. For example, if you specify `-lfoo', `ld.exe' will look first for `libfoo.a' and then for `foo.lib'. You may install GNU CC for Windows NT in one of two ways, depending on whether or not you have a Unix-like shell and various Unix-like utilities. 1. If you do not have a Unix-like shell and few Unix-like utilities, you will use a DOS style batch script called `configure.bat'. Invoke it as `configure winnt' from an MSDOS console window or from the program manager dialog box. `configure.bat' assumes you have already installed and have in your path a Unix-like `sed' program which is used to create a working `Makefile' from `Makefile.in'. `Makefile' uses the Microsoft Nmake program maintenance utility and the Visual C/C++ V8.00 compiler to build GNU CC. You need only have the utilities `sed' and `touch' to use this installation method, which only automatically builds the compiler itself. You must then examine what `fixinc.winnt' does, edit the header files by hand and build `libgcc.a' manually. 2. The second type of installation assumes you are running a Unix-like shell, have a complete suite of Unix-like utilities in your path, and have a previous version of GNU CC already installed, either through building it via the above installation method or acquiring a pre-built binary. In this case, use the `configure' script in the normal fashion. `i860-intel-osf1' This is the Paragon. If you have version 1.0 of the operating system, see *Note Installation Problems::, for special things you need to do to compensate for peculiarities in the system. `*-lynx-lynxos' LynxOS 2.2 and earlier comes with GNU CC 1.x already installed as `/bin/gcc'. You should compile with this instead of `/bin/cc'. You can tell GNU CC 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 GNU CC will use the installed tools, which produce a.out format executables. `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_4484 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 *Note 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 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. 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-riscos`rev'' Default configuration for RISC-OS, revision `rev'. `mips-mips-riscos`rev'bsd' BSD 4.3 configuration for RISC-OS, revision `rev'. `mips-mips-riscos`rev'sysv4' System V.4 configuration for RISC-OS, revision `rev'. `mips-mips-riscos`rev'sysv' 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 *Note Installation Problems::, for more details). `mips-sgi-*' 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. 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. `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. To enable debugging under Irix 5, you must use GNU as 2.5 or later, and use the `--with-gnu-as' configure option when configuring gcc. GNU as is distributed as part of the binutils package. `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 '. `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' `powerpc-*-aix' Various early versions of each release of the IBM XLC compiler will not bootstrap GNU CC. Symptoms include differences between the stage2 and stage3 object files, and errors when compiling `libgcc.a' or `enquire'. Known problematic releases include: xlc-1.2.1.8, xlc-1.3.0.0 (distributed with AIX 3.2.5), and xlc-1.3.0.19. Both xlc-1.2.1.28 and xlc-1.3.0.24 (PTF 432238) are known to produce working versions of GNU CC, but most other recent releases correctly bootstrap GNU CC. Also, releases of AIX prior to AIX 3.2.4 include a version of the IBM assembler which does not accept debugging directives: assembler updates are available as PTFs. Also, if you are using AIX 3.2.5 or greater and the GNU assembler, you must have a version modified after October 16th, 1995 in order for the GNU C compiler to build. See the file `README.RS6000' for more details on of these problems. GNU CC does not yet support the 64-bit PowerPC instructions. Objective C does not work on this architecture because it makes assumptions that are incompatible with the calling conventions. 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". Due to changes in the way that GNU CC invokes the binder (linker) for AIX 4.1, you may now receive warnings of duplicate symbols from the link step that were not reported before. The assembly files generated by GNU CC for AIX have always 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. `powerpc-*-elf' `powerpc-*-sysv4' PowerPC system in big endian mode, running System V.4. This configuration is currently under development. `powerpc-*-eabiaix' Embedded PowerPC system in big endian mode with -mcall-aix selected as the default. This system is currently under development. `powerpc-*-eabisim' Embedded PowerPC system in big endian mode for use in running under the PSIM simulator. This system is currently under development. `powerpc-*-eabi' Embedded PowerPC system in big endian mode. This configuration is currently under development. `powerpcle-*-elf' `powerpcle-*-sysv4' PowerPC system in little endian mode, running System V.4. This configuration is currently under development. `powerpcle-*-sysv4' Embedded PowerPC system in little endian mode. This system is currently under development. `powerpcle-*-eabisim' Embedded PowerPC system in little endian mode for use in running under the PSIM simulator. This system is currently under development. `powerpcle-*-eabi' Embedded PowerPC system in little endian mode. This configuration is currently under development. `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 *Note Sun Install::, for information on installing GNU CC on Sun systems. `vax-dec-vms' See *Note 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 *Note 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.  File: gcc.info, Node: Other Dir, Next: Cross-Compiler, Prev: Configurations, Up: Installation Compilation in a Separate Directory =================================== If you wish to build the object files and executables in a directory other than the one containing the source files, here is what you must do differently: 1. Make sure you have a version of Make that supports the `VPATH' feature. (GNU Make supports it, as do Make versions on most BSD systems.) 2. If you have ever run `configure' in the source directory, you must undo the configuration. Do this by running: make distclean 3. Go to the directory in which you want to build the compiler before running `configure': mkdir gcc-sun3 cd gcc-sun3 On systems that do not support symbolic links, this directory must be on the same file system as the source code directory. 4. Specify where to find `configure' when you run it: ../gcc/configure ... This also tells `configure' where to find the compiler sources; `configure' takes the directory from the file name that was used to invoke it. But if you want to be sure, you can specify the source directory with the `--srcdir' option, like this: ../gcc/configure --srcdir=../gcc OTHER OPTIONS The directory you specify with `--srcdir' need not be the same as the one that `configure' is found in. Now, you can run `make' in that directory. You need not repeat the configuration steps shown above, when ordinary source files change. You must, however, run `configure' again when the configuration files change, if your system does not support symbolic links.  File: gcc.info, Node: Cross-Compiler, Next: Sun Install, Prev: Other Dir, Up: Installation Building and Installing a Cross-Compiler ======================================== GNU CC can function as a cross-compiler for many machines, but not all. * Cross-compilers for the Mips as target using the Mips assembler currently do not work, because the auxiliary programs `mips-tdump.c' and `mips-tfile.c' can't be compiled on anything but a Mips. It does work to cross compile for a Mips if you use the GNU assembler and linker. * Cross-compilers between machines with different floating point formats have not all been made to work. GNU CC now has a floating point emulator with which these can work, but each target machine description needs to be updated to take advantage of it. * Cross-compilation between machines of different word sizes is somewhat problematic and sometimes does not work. Since GNU CC generates assembler code, you probably need a cross-assembler that GNU CC can run, in order to produce object files. If you want to link on other than the target machine, you need a cross-linker as well. You also need header files and libraries suitable for the target machine that you can install on the host machine. * Menu: * Steps of Cross:: Using a cross-compiler involves several steps that may be carried out on different machines. * Configure Cross:: Configuring a cross-compiler. * Tools and Libraries:: Where to put the linker and assembler, and the C library. * Cross Headers:: Finding and installing header files for a cross-compiler. * Cross Runtime:: Supplying arithmetic runtime routines (`libgcc1.a'). * Build Cross:: Actually compiling the cross-compiler.  File: gcc.info, Node: Steps of Cross, Next: Configure Cross, Up: Cross-Compiler Steps of Cross-Compilation -------------------------- To compile and run a program using a cross-compiler involves several steps: * Run the cross-compiler on the host machine to produce assembler files for the target machine. This requires header files for the target machine. * Assemble the files produced by the cross-compiler. You can do this either with an assembler on the target machine, or with a cross-assembler on the host machine. * Link those files to make an executable. You can do this either with a linker on the target machine, or with a cross-linker on the host machine. Whichever machine you use, you need libraries and certain startup files (typically `crt....o') for the target machine. It is most convenient to do all of these steps on the same host machine, since then you can do it all with a single invocation of GNU CC. This requires a suitable cross-assembler and cross-linker. For some targets, the GNU assembler and linker are available.  File: gcc.info, Node: Configure Cross, Next: Tools and Libraries, Prev: Steps of Cross, Up: Cross-Compiler Configuring a Cross-Compiler ---------------------------- To build GNU CC as a cross-compiler, you start out by running `configure'. Use the `--target=TARGET' to specify the target type. If `configure' was unable to correctly identify the system you are running on, also specify the `--build=BUILD' option. For example, here is how to configure for a cross-compiler that produces code for an HP 68030 system running BSD on a system that `configure' can correctly identify: ./configure --target=m68k-hp-bsd4.3  File: gcc.info, Node: Tools and Libraries, Next: Cross Headers, Prev: Configure Cross, Up: Cross-Compiler Tools and Libraries for a Cross-Compiler ---------------------------------------- If you have a cross-assembler and cross-linker available, you should install them now. Put them in the directory `/usr/local/TARGET/bin'. Here is a table of the tools you should put in this directory: `as' This should be the cross-assembler. `ld' This should be the cross-linker. `ar' This should be the cross-archiver: a program which can manipulate archive files (linker libraries) in the target machine's format. `ranlib' This should be a program to construct a symbol table in an archive file. The installation of GNU CC will find these programs in that directory, and copy or link them to the proper place to for the cross-compiler to find them when run later. The easiest way to provide these files is to build the Binutils package and GAS. Configure them with the same `--host' and `--target' options that you use for configuring GNU CC, then build and install them. They install their executables automatically into the proper directory. Alas, they do not support all the targets that GNU CC supports. If you want to install libraries to use with the cross-compiler, such as a standard C library, put them in the directory `/usr/local/TARGET/lib'; installation of GNU CC copies all all the files in that subdirectory into the proper place for GNU CC to find them and link with them. Here's an example of copying some libraries from a target machine: ftp TARGET-MACHINE lcd /usr/local/TARGET/lib cd /lib get libc.a cd /usr/lib get libg.a get libm.a quit The precise set of libraries you'll need, and their locations on the target machine, vary depending on its operating system. Many targets require "start files" such as `crt0.o' and `crtn.o' which are linked into each executable; these too should be placed in `/usr/local/TARGET/lib'. There may be several alternatives for `crt0.o', for use with profiling or other compilation options. Check your target's definition of `STARTFILE_SPEC' to find out what start files it uses. Here's an example of copying these files from a target machine: ftp TARGET-MACHINE lcd /usr/local/TARGET/lib prompt cd /lib mget *crt*.o cd /usr/lib mget *crt*.o quit  File: gcc.info, Node: Cross Runtime, Next: Build Cross, Prev: Cross Headers, Up: Cross-Compiler `libgcc.a' and Cross-Compilers ------------------------------ Code compiled by GNU CC uses certain runtime support functions implicitly. Some of these functions can be compiled successfully with GNU CC itself, but a few cannot be. These problem functions are in the source file `libgcc1.c'; the library made from them is called `libgcc1.a'. When you build a native compiler, these functions are compiled with some other compiler-the one that you use for bootstrapping GNU CC. Presumably it knows how to open code these operations, or else knows how to call the run-time emulation facilities that the machine comes with. But this approach doesn't work for building a cross-compiler. The compiler that you use for building knows about the host system, not the target system. So, when you build a cross-compiler you have to supply a suitable library `libgcc1.a' that does the job it is expected to do. To compile `libgcc1.c' with the cross-compiler itself does not work. The functions in this file are supposed to implement arithmetic operations that GNU CC does not know how to open code for your target machine. If these functions are compiled with GNU CC itself, they will compile into infinite recursion. On any given target, most of these functions are not needed. If GNU CC can open code an arithmetic operation, it will not call these functions to perform the operation. It is possible that on your target machine, none of these functions is needed. If so, you can supply an empty library as `libgcc1.a'. Many targets need library support only for multiplication and division. If you are linking with a library that contains functions for multiplication and division, you can tell GNU CC to call them directly by defining the macros `MULSI3_LIBCALL', and the like. These macros need to be defined in the target description macro file. For some targets, they are defined already. This may be sufficient to avoid the need for libgcc1.a; if so, you can supply an empty library. Some targets do not have floating point instructions; they need other functions in `libgcc1.a', which do floating arithmetic. Recent versions of GNU CC have a file which emulates floating point. With a certain amount of work, you should be able to construct a floating point emulator that can be used as `libgcc1.a'. Perhaps future versions will contain code to do this automatically and conveniently. That depends on whether someone wants to implement it. Some embedded targets come with all the necessary `libgcc1.a' routines written in C or assembler. These targets build `libgcc1.a' automatically and you do not need to do anything special for them. Other embedded targets do not need any `libgcc1.a' routines since all the necessary operations are supported by the hardware. If your target system has another C compiler, you can configure GNU CC as a native compiler on that machine, build just `libgcc1.a' with `make libgcc1.a' on that machine, and use the resulting file with the cross-compiler. To do this, execute the following on the target machine: cd TARGET-BUILD-DIR ./configure --host=sparc --target=sun3 make libgcc1.a And then this on the host machine: ftp TARGET-MACHINE binary cd TARGET-BUILD-DIR get libgcc1.a quit Another way to provide the functions you need in `libgcc1.a' is to define the appropriate `perform_...' macros for those functions. If these definitions do not use the C arithmetic operators that they are meant to implement, you should be able to compile them with the cross-compiler you are building. (If these definitions already exist for your target file, then you are all set.) To build `libgcc1.a' using the perform macros, use `LIBGCC1=libgcc1.a OLDCC=./xgcc' when building the compiler. Otherwise, you should place your replacement library under the name `libgcc1.a' in the directory in which you will build the cross-compiler, before you run `make'.  File: gcc.info, Node: Cross Headers, Next: Cross Runtime, Prev: Tools and Libraries, Up: Cross-Compiler Cross-Compilers and Header Files -------------------------------- If you are cross-compiling a standalone program or a program for an embedded system, then you may not need any header files except the few that are part of GNU CC (and those of your program). However, if you intend to link your program with a standard C library such as `libc.a', then you probably need to compile with the header files that go with the library you use. The GNU C compiler does not come with these files, because (1) they are system-specific, and (2) they belong in a C library, not in a compiler. If the GNU C library supports your target machine, then you can get the header files from there (assuming you actually use the GNU library when you link your program). If your target machine comes with a C compiler, it probably comes with suitable header files also. If you make these files accessible from the host machine, the cross-compiler can use them also. Otherwise, you're on your own in finding header files to use when cross-compiling. When you have found suitable header files, put them in `/usr/local/TARGET/include', before building the cross compiler. Then installation will run fixincludes properly and install the corrected versions of the header files where the compiler will use them. Provide the header files before you build the cross-compiler, because the build stage actually runs the cross-compiler to produce parts of `libgcc.a'. (These are the parts that *can* be compiled with GNU CC.) Some of them need suitable header files. Here's an example showing how to copy the header files from a target machine. On the target machine, do this: (cd /usr/include; tar cf - .) > tarfile Then, on the host machine, do this: ftp TARGET-MACHINE lcd /usr/local/TARGET/include get tarfile quit tar xf tarfile