Using and Porting GNU CC
Using and Porting GNU CC
Here are the possible CPU types:
1750a, a29k, alpha, arm, cn, clipper, elxsi, h8300, hppa1.0, hppa1.1, i370, i386, i486, i860, i960, m68000, m68k, m88k, mips, ns32k, pyramid, romp, rs6000, sh, sparc, sparclite, sparc64, vax, we32k.
Here are the recognized company names. As you can see, customary abbreviations are used rather than the longer official names.
acorn, alliant, altos, apollo, att, bull, cbm, convergent, convex, crds, dec, dg, dolphin, elxsi, encore, harris, hitachi, hp, ibm, intergraph, isi, mips, motorola, ncr, next, ns, omron, plexus, sequent, sgi, sony, sun, tti, unicom.
The company name is meaningful only to disambiguate when the rest of
the information supplied is insufficient. You can omit it, writing
just `cpu-system', if it is not needed. For example,
`vax-ultrix4.2' is equivalent to `vax-dec-ultrix4.2'.
Here is a list of system types:
386bsd, aix, acis, amigados, aos, aout, bosx, bsd, clix, ctix, cxux, dgux, dynix, ebmon, elf, esix, freebsd, hms, genix, gnu, hiux, hpux, iris, irix, isc, linux, luna, lynxos, mach, minix, msdos, mvs, netbsd, newsos, nindy, ns, osf, osfrose, riscix, riscos, rtu, sco, solaris, sunos, sym, sysv, ultrix, unicos, uniplus, unos, vms, vxworks, xenix.
You can omit the system type; then `configure' guesses the
operating system from the CPU and company.
You can add a version number to the system type; this may or may not
make a difference. For example, you can write `bsd4.3' or
`bsd4.4' to distinguish versions of BSD. In practice, the version
number is most needed for `sysv3' and `sysv4', which are often
treated differently.
If you specify an impossible combination such as `i860-dg-vms',
then you may get an error message from `configure', or it may
ignore part of the information and do the best it can with the rest.
`configure' always prints the canonical name for the alternative
that it used. GNU CC does not support all possible alternatives.
Often a particular model of machine has a name. Many machine names are
recognized as aliases for CPU/company combinations. Thus, the machine
name `sun3', mentioned above, is an alias for `m68k-sun'.
Sometimes we accept a company name as a machine name, when the name is
popularly used for a particular machine. Here is a table of the known
machine names:
3300, 3b1, 3bn, 7300, altos3068, altos, apollo68, att-7300, balance, convex-cn, crds, decstation-3100, decstation, delta, encore, fx2800, gmicro, hp7nn, hp8nn, hp9k2nn, hp9k3nn, hp9k7nn, hp9k8nn, iris4d, iris, isi68, m3230, magnum, merlin, miniframe, mmax, news-3600, news800, news, next, pbd, pc532, pmax, powerpc, ps2, risc-news, rtpc, sun2, sun386i, sun386, sun3, sun4, symmetry, tower-32, tower.
Remember that a machine name specifies both the cpu type and the company
name.
If you want to install your own homemade configuration files, you can
use `local' as the company name to access them. If you use
configuration `cpu-local', the configuration name
without the cpu prefix
is used to form the configuration file names.
Thus, if you specify `m68k-local', configuration uses
files `local.md', `local.h', `local.c',
`xm-local.h', `t-local', and `x-local', all in the
directory `config/m68k'.
Here is a list of configurations that have special treatment or special things you must know:
1750a-*-*'
You should ignore a fatal error during the building of libgcc (libgcc is not yet implemented for the 1750A.)
The Tektronix MIL-STD-1750A Assembler requires the file
`m1750.inc', which is found in the directory `config/1750a'.
GNU CC produced the same sections as the Fairchild F9450 C Compiler, namely:
NREL
SREL
KREL
IREL
The smallest addressable unit is 16 bits (BITS_PER_UNIT is 16). This means that type `char' is represented with a 16-bit word per character. The 1750A's "Load/Store Upper/Lower Byte" instructions are not used by GNU CC.
There is a problem with long argument lists to functions. The compiler aborts if the sum of space needed by all arguments exceeds 14 words. This is because the arguments are passed in registers (R0..R13) not on the stack, and there is a problem with passing further arguments (i.e. beyond those in R0..R13) via the stack.
If efficiency is less important than using long argument lists, you
can change the definition of the FUNCTION_ARG macro in
`config/1750/1750a.h' to always return zero. If you do that,
GNU CC will pass all parameters on the stack.
alpha-*-osf1'
GNU CC writes a `.verstamp' directive to the assembler output file
unless it is built as a cross-compiler. It gets the version to use from
the system header file `/usr/include/stamp.h'. If you install a
new version of OSF/1, you should rebuild GCC to pick up the new version
stamp.
Note that since the Alpha is a 64-bit architecture, cross-compilers from 32-bit machines will not generate code as efficient as that generated when the compiler is running on a 64-bit machine because many optimizations that depend on being able to represent a word on the target in an integral value on the host cannot be performed. Building cross-compilers on the Alpha for 32-bit machines has only been tested in a few cases and may not work properly.
make compare may fail on old versions of OSF/1 unless you add
`-save-temps' to CFLAGS. On these systems, the name of the
assembler input file is stored in the object file, and that makes
comparison fail if it differs between the stage1 and
stage2 compilations. The option `-save-temps' forces a
fixed name to be used for the assembler input file, instead of a
randomly chosen name in `/tmp'. Do not add `-save-temps'
unless the comparisons fail without that option. If you add
`-save-temps', you will have to manually delete the `.i' and
`.s' files after each series of compilations.
GNU CC now supports both the native (ECOFF) debugging format used by DBX
and GDB and an encapsulated STABS format for use only with GDB. See the
discussion of the `--with-stabs' option of `configure' above
for more information on these formats and how to select them.
There is a bug in DEC's assembler that produces incorrect line numbers
for ECOFF format when the `.align' directive is used. To work
around this problem, GNU CC will not emit such alignment directives
while writing ECOFF format debugging information even if optimization is
being performed. Unfortunately, this has the very undesirable
side-effect that code addresses when `-O' is specified are
different depending on whether or not `-g' is also specified.
To avoid this behavior, specify `-gstabs+' and use GDB instead of
DBX. DEC is now aware of this problem with the assembler and hopes to
provide a fix shortly.
arm'
You may need to make a variant of the file `arm.h' for your particular
configuration.
arm-*-riscix'
a29k'
You may need to make a variant of the file `a29k.h' for your
particular configuration.
a29k-*-bsd'
decstation-*'
decstation-ultrix'
decstation-osf1'
decstation-osfrose'
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'
mrs@cygnus.com for more details.
h8300-*-*'
hppa*-*-*'
The easiest way to handle this problem is to use `configure hpnnn' or `configure hpnnn-hpux', where nnn is
the model number of the machine. Then `configure' will figure out
if the machine is a 1.0 or 1.1. Use `uname -a' to find out the
model number of your machine.
`-g' does not work on HP-UX, since that system uses a peculiar
debugging format which GNU CC does not know about. However, `-g'
will work if you also use GAS and GDB in conjunction with GCC. We
highly recommend using GAS for all HP-PA configurations.
You should be using GAS-2.3 (or later) along with GDB-4.12 (or later). These can be retrieved from all the traditional GNU ftp archive sites.
Build GAS and install the resulting binary as:
/usr/local/lib/gcc-lib/configuration/gccversion/as
where configuration is the configuration name (perhaps
`hpnnn-hpux') and gccversion is the GNU CC version
number. Do this before starting the build process, otherwise you will
get errors from the HPUX assembler while building `libgcc2.a'. The
command
make install-dir
will create the necessary directory hierarchy so you can install GAS before building GCC.
To enable debugging, configure GNU CC with the `--with-gnu-as' option
before building.
It has been reported that GNU CC produces invalid assembly code for 1.1 machines running HP-UX 8.02 when using the HP assembler. Typically the errors look like this:
as: bug.s @line#15 [err#1060]
Argument 0 or 2 in FARG upper
- lookahead = ARGW1=FR,RTNVAL=GR
as: foo.s @line#28 [err#1060]
Argument 0 or 2 in FARG upper
- lookahead = ARGW1=FR
You can check the version of HP-UX you are running by executing the command
`uname -r'. If you are indeed running HP-UX 8.02 on a PA and
using the HP assembler then configure GCC with "hpnnn-hpux8.02".
i370-*-*'
i386-*-linux'
i386-*-sco'
i386-*-sco3.2.4'
i386-*-isc'
i386-*-esix'
i386-ibm-aix'
i386-sequent'
string.h' containing just one line:
`#include <strings.h>'.
i386-sun-sunos4'
libgcc2.c'. GNU CC version 2 compiled with GNU CC (any version)
seems not to have this problem.
See Sun Install, for information on installing GNU CC on Sun systems.
i860-intel-osf1'
m68000-hp-bsd'
law@cs.utah.edu
to get binaries of GNU CC for bootstrapping.
m68k-altos'
README.ALTOS'.
m68k-att-sysv'
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.
#include "config.h"' line on line 37 of
`cccp.c' and do `make cpp'. This makes a preliminary version
of GNU cpp.
/lib/cpp' and copy the preliminary GNU cpp to that
file name.
cccp.c', or reinstall the original version,
and do `make cpp' again.
/lib/cpp'.
obstack_free in the file
`tree.c' with _obstack_free.
make to get the first-stage GNU CC.
/lib/cpp'.
m68k-bull-sysv'
--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'
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'
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'
See Sun Install, for information on installing GNU CC on Sun systems.
m88k-*-svr3'
It is best, however, to use an older version of GNU CC for bootstrapping if you have one.
m88k-*-dgux'
eval `sde-target m88kbcs`
m88k-tektronix-sysv3'
mips-mips-bsd'
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*'
-Wf,-XNg1500' option in
order to compile `cp/parse.c'. If you use the `-O2'
optimization option, you also need to use `-Olimit 3000'.
Both of these options are automatically generated in the
`Makefile' that the shell script `configure' builds.
If you override the CC make variable and use the MIPS
compilers, you may need to add `-Wf,-XNg1500 -Olimit 3000'.
MIPS computers running RISC-OS can support four different personalities: default, BSD 4.3, System V.3, and System V.4 (older versions of RISC-OS don't support V.4). To configure GCC for these platforms use the following configurations:
mips-mips-riscosrev'
rev.
mips-mips-riscosrevbsd'
rev.
mips-mips-riscosrevsysv4'
rev.
mips-mips-riscosrevsysv'
rev.
The revision rev mentioned above is the revision of
RISC-OS to use. You must reconfigure GCC when going from a
RISC-OS revision 4 to RISC-OS revision 5. This has the effect of
avoiding a linker
bug (see Installation Problems, for more details).
mips-sgi-*'
make compare may fail on version 5 of IRIX unless you add
`-save-temps' to CFLAGS. On these systems, the name of the
assembler input file is stored in the object file, and that makes
comparison fail if it differs between the stage1 and
stage2 compilations. The option `-save-temps' forces a
fixed name to be used for the assembler input file, instead of a
randomly chosen name in `/tmp'. Do not add `-save-temps'
unless the comparisons fail without that option. If you do you
`-save-temps', you will have to manually delete the `.i' and
`.s' files after each series of compilations.
The MIPS C compiler needs to be told to increase its table size
for switch statements with the `-Wf,-XNg1500' option in
order to compile `cp/parse.c'. If you use the `-O2'
optimization option, you also need to use `-Olimit 3000'.
Both of these options are automatically generated in the
`Makefile' that the shell script `configure' builds.
If you override the CC make variable and use the MIPS
compilers, you may need to add `-Wf,-XNg1500 -Olimit 3000'.
On Irix version 4.0.5F, and perhaps on some other versions as well,
there is an assembler bug that reorders instructions incorrectly. To
work around it, specify the target configuration
`mips-sgi-irix4loser'. This configuration inhibits assembler
optimization.
In a compiler configured with target `mips-sgi-irix4', you can turn
off assembler optimization by using the `-noasmopt' option. This
compiler option passes the option `-O0' to the assembler, to
inhibit reordering.
The `-noasmopt' option can be useful for testing whether a problem
is due to erroneous assembler reordering. Even if a problem does not go
away with `-noasmopt', it may still be due to assembler
reordering---perhaps GNU CC itself was miscompiled as a result.
See the file `README.IRIX5' for information on how to make
debugging work.
mips-sony-sysv'
ns32k-encore'
ns32k-*-genix'
alloca
and malloc; you must get the compiled versions of these from GNU
Emacs.
ns32k-sequent'
string.h' containing just one line:
`#include <strings.h>'.
ns32k-utek'
tektronix!reed!mason' to get
binaries of GNU CC for bootstrapping.
romp-*-aos'
romp-*-mach'
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'
README.RS6000' for more details.
The PowerPC and POWER2 architectures are now supported, but have not been very extensively tested due to lack of appropriate systems. Only AIX is supported on the PowerPC. GNU CC does not yet support the 64-bit PowerPC instructions.
Objective C does not work on this architecture.
AIX on the RS/6000 provides support (NLS) for environments outside of the United States. Compilers and assemblers use NLS to support locale-specific representations of various objects including floating-point numbers ("." vs "," for separating decimal fractions). There have been problems reported where the library linked with GNU CC does not produce the same floating-point formats that the assembler accepts. If you have this problem, set the LANG environment variable to "C" or "En_US".
vax-dec-ultrix'
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-*'
vax-dec-vms'
we32k-*-*'
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.