Installing glibc headers before building bootstrap gcc (was: Re: [PATCH] missing #ifndef inhibit_libc in gcc/config/rs6000/linux.h)

Dan Kegel dank@kegel.com
Mon Nov 10 00:25:00 GMT 2003


Daniel Jacobowitz wrote:
> On Tue, Oct 28, 2003 at 11:23:59PM -0800, Dan Kegel wrote:
> 
>>Daniel Jacobowitz wrote:
>>
>>>>>Sadly, in order to build a proper Linux toolchain, inhibit_libc
>>>>>is absolutely required, even on Linux.  This is because you have
>>>>>to first build a bootstrap compiler without glibc.
>>>>
>>>>This is a lie. 
>>
>>? The sequence required to build a Linux toolchain without
>>the build system's headers and libraries leaking in is
>>  glibc: make install-headers  (using native compiler)
>>  gcc:   make all-gcc install-gcc   (with inhibit_libc defined, perhaps 
>>  indirectly)
> 
> No.  That's not at all necessary; just --disable-shared.  I build gcc
> with just headers and no inhibit_libc every day.

I just tried building a bootstrap compiler without setting
inhibit_libc, that is, without passing the option --with-newlib
(which is customarily used when building bootstrap compilers
precisely because it sets inhibit_libc).  The build failed as expected with

In file included from /home/dank/crosstool-0.25/build/powerpc-405-linux-gnu/gcc-3.3.2-glibc-2.3.2/gcc-3.3.2/gcc/tsystem.h:72,
                  from /home/dank/crosstool-0.25/build/powerpc-405-linux-gnu/gcc-3.3.2-glibc-2.3.2/gcc-3.3.2/gcc/crtstuff.c:62:
/opt/crosstool/powerpc-405-linux-gnu/gcc-3.3.2-glibc-2.3.2/powerpc-405-linux-gnu/include/stdio.h:138:28: bits/stdio_lim.h: No such file or directory
make[1]: *** [crtbegin.o] Error 1

which is the same error I got earlier with the gcc-3.4 bug that
caused inhibit_libc to not be defined (see http://gcc.gnu.org/ml/gcc/2003-08/msg00900.html ).

So either Daniel J. is configuring his bootstrap compiler --with-newlib, or
he's installing the glibc headers more cleverly than me such that he ends up with a working bits/stdio_lim.h.

Now, stdio_lim.h is one of those files that's generated during
glibc's "make install-headers" by running $(CC)
just as errlist-compat.c is.   In the past, I ran into trouble
trying to get glibc's Makefiles to generate them, so I bypass them.
Here's the snippet of crosstool.sh which install glibc's headers before
building the bootstrap compiler:

     CC=gcc \
             ${GLIBC_DIR}/configure --host=$TARGET --prefix=/usr \
             --build=$BUILD \
             --without-cvs --disable-sanity-checks --with-headers=${PREFIX}/${TARGET}/include \
             --enable-hacker-mode

     if grep -q GLIBC_2.3 ${GLIBC_DIR}/ChangeLog; then
         # glibc-2.3.x passes cross options to $(CC) when generating errlist-compat.c, which fails without a real cross-compiler.
         # Fortunately, we don't need errlist-compat.c, since we just need .h files,
         # so work around this by creating a fake errlist-compat.c and satisfying its dependencies.
         # Another workaround might be to tell configure to not use any cross options to $(CC).
         # The real fix would be to get install-headers to not generate errlist-compat.c.
         make sysdeps/gnu/errlist.c
         mkdir -p stdio-common
         touch stdio-common/errlist-compat.c
     fi
     make cross-compiling=yes install_root=${PREFIX}/${TARGET} prefix="" install-headers

Should I be doing it some other way?

- Dan



More information about the Libc-alpha mailing list