install.texi

gcc库的原代码,对编程有很大帮助.

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.

@enumerate
@item
Comment out the @samp{#include "config.h"} line on line 37 of
@file{cccp.c} and do @samp{make cpp}.  This makes a preliminary version
of GNU cpp.

@item
Save the old @file{/lib/cpp} and copy the preliminary GNU cpp to that
file name.

@item
Undo your change in @file{cccp.c}, or reinstall the original version,
and do @samp{make cpp} again.

@item
Copy this final version of GNU cpp into @file{/lib/cpp}.

@findex obstack_free
@item
Replace every occurrence of @code{obstack_free} in the file
@file{tree.c} with @code{_obstack_free}.

@item
Run @code{make} to get the first-stage GNU CC.

@item
Reinstall the original version of @file{/lib/cpp}.

@item
Now you can compile GNU CC with itself and install it in the normal
fashion.
@end enumerate

@item 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 @samp{--with-gnu-as} to
the configure script or use GNU assembler with dbx-in-coff encapsulation
by providing @samp{--with-gnu-as --stabs}. For any problem with native 
assembler or for availability of the DPX/2 port of GAS, contact 
@code{F.Pierresteguy@@frcl.bull.fr}.

@item m68k-crds-unox
Use @samp{configure unos} for building on Unos.

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

@example
#!/bin/sh
casm $*
@end example

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

@cindex @code{alloca}, for Unos
When compiling GNU CC with the standard compiler, to overcome bugs in
the support of @code{alloca}, do not use @samp{-O} when making stage 2.
Then use the stage 2 compiler with @samp{-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 @code{ALLOCA} in @file{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 @file{cc1} fails, try putting the object files into a library
and linking from that library.

@item 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 @samp{--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.

@item 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 @ref{Sun Install}, for information on installing GNU CC on Sun
systems.

@item 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.

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

If you do not specify a configuration name, @file{configure} guesses the
configuration based on the current software development environment.

@item 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.

@item 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
@code{memcpy}, @code{memcmp}, and @code{memset}.  If your system lacks
these, you must remove or undo the definition of
@code{TARGET_MEM_FUNCTIONS} in @file{mips-bsd.h}.

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

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

@table @samp
@item mips-mips-riscos@code{rev}
Default configuration for RISC-OS, revision @code{rev}.

@item mips-mips-riscos@code{rev}bsd
BSD 4.3 configuration for RISC-OS, revision @code{rev}.

@item mips-mips-riscos@code{rev}sysv4
System V.4 configuration for RISC-OS, revision @code{rev}.

@item mips-mips-riscos@code{rev}sysv
System V.3 configuration for RISC-OS, revision @code{rev}.
@end table

The revision @code{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
@ifclear INSTALLONLY
bug (see @ref{Installation Problems}, for more details).
@end ifclear
@ifset INSTALLONLY
bug.
@end ifset

@item 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.

@code{make compare} may fail on version 5 of IRIX unless you add
@samp{-save-temps} to @code{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 @code{stage1} and
@code{stage2} compilations.  The option @samp{-save-temps} forces a
fixed name to be used for the assembler input file, instead of a
randomly chosen name in @file{/tmp}.  Do not add @samp{-save-temps}
unless the comparisons fail without that option.  If you do you
@samp{-save-temps}, you will have to manually delete the @samp{.i} and
@samp{.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 @samp{-Wf,-XNg1500} option in
order to compile @file{cp/parse.c}.  If you use the @samp{-O2}
optimization option, you also need to use @samp{-Olimit 3000}.
Both of these options are automatically generated in the
@file{Makefile} that the shell script @file{configure} builds.
If you override the @code{CC} make variable and use the MIPS
compilers, you may need to add @samp{-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
@samp{mips-sgi-irix4loser}.  This configuration inhibits assembler
optimization.

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

The @samp{-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 @samp{-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 @samp{--with-gnu-as} configure option when configuring gcc.
GNU as is distributed as part of the binutils package.  

@item 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.

@item ns32k-encore
Encore ns32000 system.  Encore systems are supported only under BSD.

@item ns32k-*-genix
National Semiconductor ns32000 system.  Genix has bugs in @code{alloca}
and @code{malloc}; you must get the compiled versions of these from GNU
Emacs.

@item ns32k-sequent
Go to the Berkeley universe before compiling.  In addition, you probably
need to create a file named @file{string.h} containing just one line:
@samp{#include <strings.h>}.

@item ns32k-utek
UTEK ns32000 system (``merlin'').  The C compiler that comes with this
system cannot compile GNU CC; contact @samp{tektronix!reed!mason} to get
binaries of GNU CC for bootstrapping.

@item romp-*-aos
@itemx 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 @code{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.

@item rs6000-*-aix
@itemx 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 @file{libgcc.a} or
@file{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 @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.

@item powerpc-*-elf
@itemx powerpc-*-sysv4
PowerPC system in big endian mode, running System V.4.

This configuration is currently under development.

@item powerpc-*-eabiaix
Embedded PowerPC system in big endian mode with -mcall-aix selected as
the default.  This system is currently under development.

@item powerpc-*-eabisim