Bootstrap failure on SuSE 10.1

[Wolfgang Bangerth <bangerth at math dot tamu dot edu>]

I must be doing something extraordinarily stupid, but I can't figure out
what it is: I can't bootstrap anymore since subversion revisions from
early January this year on a system as widely available as stock SuSE10.1.

Here's what's happening: starting with revision 109241
-----------------------
config:
2006-01-02  Paolo Bonzini  <bonzini@gnu.org>

        PR target/25259
        * stdint.m4: New.

gcc:
2006-01-02  Paolo Bonzini  <bonzini@gnu.org>

        PR target/25259
        * Makefile.in (DECNUMINC): Include libdecnumber's build directory.

[...]
------------------------
I get bootstrap failures like this:

gcc -c   -g -DENABLE_CHECKING -DENABLE_ASSERT_CHECKING -DIN_GCC   -W -Wall
   -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -pedantic
   -Wno-long-long -Wno-variadic-macros -Wold-style-definition
   -Wmissing-format-attribute -fno-common   -DHAVE_CONFIG_H -I. -I.
   -I../../svn-mainline/gcc -I../../svn-mainline/gcc/.
   -I../../svn-mainline/gcc/../include
   -I../../svn-mainline/gcc/../libcpp/include
   -I../../svn-mainline/gcc/../libdecnumber -I../libdecnumber
   ../../svn-mainline/gcc/c-lang.c -o c-lang.o
In file included from ../../svn-mainline/gcc/input.h:25,
                 from ../../svn-mainline/gcc/tree.h:26,
                 from ../../svn-mainline/gcc/c-lang.c:27:
../../svn-mainline/gcc/../libcpp/include/line-map.h:56: error: 'CHAR_BIT'
undeclared here (not in a function)


I can prevent the failure if I remove the -I../libdecnumber from the
command line. The reason is that c-lang.c contains #include "config.h" at
the beginning, and for some reason the preprocessor decides to pick up the
config.h from ../libdecnumber instead of from ./ . If I run above
commandline with -E instead of -c, here is the top of the preprocessor
output with -I../libdecnumber:
--------------------
# 1 "../../svn-mainline/gcc/c-lang.c"
# 1 "<built-in>"
# 1 "<command line>"
# 1 "../../svn-mainline/gcc/c-lang.c"
# 23 "../../svn-mainline/gcc/c-lang.c"
# 1 "../libdecnumber/config.h" 1
# 24 "../../svn-mainline/gcc/c-lang.c" 2
--------------------
On the other hand, when I omit -I../libdecnumber, I get the output that
was probably expected:
--------------------
# 1 "../../svn-mainline/gcc/c-lang.c"
# 1 "<built-in>"
# 1 "<command line>"
# 1 "../../svn-mainline/gcc/c-lang.c"
# 23 "../../svn-mainline/gcc/c-lang.c"
# 1 "./config.h" 1 3


# 1 "./auto-host.h" 1 3
--------------------

This must be something that someone has seen before and knows how to deal
with. Any ideas?

Best
  Wolfgang


PS: Just in case, this is how I build:
  ../svn-mainline/configure --prefix=/home/bangerth/bin/gcc-4.2-pre
       --enable-languages=c,c++   &&   make bootstrap

-------------------------------------------------------------------------
Wolfgang Bangerth                email:            bangerth@math.tamu.edu
                                 www: http://www.math.tamu.edu/~bangerth/