I am trying to build mainline GCC (revision 156033) configured
with -enable-build-with-cxx .

I get the following error during bootstrap:

make[3]: Entering directory `/user/inria/fsf/bld-gcc-cxx2/libcpp'
g++  -I../../gcc/libcpp -I. -I../../gcc/libcpp/../include
-I../../gcc/libcpp/include  -g -W -Wall -Wwrite-strings
-Wmissing-format-attribute -pedantic -Wno-long-long  -I../../gcc/libcpp -I.
-I../../gcc/libcpp/../include -I../../gcc/libcpp/include  -c -o charset.o -MT
charset.o -MMD -MP -MF .deps/charset.Tpo ../../gcc/libcpp/charset.c
In file included from ../../gcc/libcpp/system.h:341,
                 from ../../gcc/libcpp/charset.c:22:
../../gcc/libcpp/../include/libiberty.h:106: error: new declaration ‘char*
basename(const char*)’
/usr/include/string.h:601: error: ambiguates old declaration ‘const char*
basename(const char*)’
make[3]: *** [charset.o] Error 1
make[3]: Leaving directory `/user/inria/fsf/bld-gcc-cxx2/libcpp'
make[2]: *** [all-stage1-libcpp] Error 2
make[2]: Leaving directory `/user/inria/fsf/bld-gcc-cxx2'
make[1]: *** [stage1-bubble] Error 2
make[1]: Leaving directory `/user/inria/fsf/bld-gcc-cxx2'
make: *** [bootstrap] Error 2


-- 
           Summary: --enable-build-with-cxx bootstrap fails on i686-pc-
                    linux-gnu (Fedora12)
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Keywords: build
          Severity: normal
          Priority: P3
         Component: bootstrap
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: amylaar at gcc dot gnu dot org
  GCC host triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42798