Cannot build both gcc and new snapshot on i686-pc-linux-gnu

[Russell Davidson <russell at ehess dot cnrs-mrs dot fr>]

When trying to build the new snapshot (libstdc++-2.90.8) as the default
library for gcc-2.95.2 (release), I followed the instructions for
untarring the libstdc++ sources into the gcc source directory, configured,
and launched make bootstrap.

The compiler itself compiles with no trouble, and so does most of the
library. But it fails when compiling
gcc-2.95.2/libstdc++/src/stringMAIN.cc and wstringMAIN.cc.
This happens because of the flag -Werror, which causes warnings to be
treated as errors, thus halting the compilation.

The warnings came from the compiler claiming not to be able to inline the
functions _S_construct (at line 712 of basic_string.h), replace (at line
675 of the same file), and assign (line 541 of the same file).

By turning off the -Werror flag just for those two files, I was able to
complete the compilation of the library. However, when I then ran make
check, almost everything failed. At first, I thought that this was due to
mkcheck calling the g++ on the system, rather than the newly built one,
and so I changed the PATH variable so that g++ was the new one, the one
that had built the library. Just as bad. The errors are gross, syntax
errors mostly, and so there must be some flag or definition that isn't
correct. 

Incidentally, when I just built the library only, with my existing g++
(the 2.95.2 release), turning off namespaces as instructed, everything
built just fine, and the only failures on make check were the ones we were
told to expect. 

Does someone know what is causing this odd behaviour? I am no good with
autoconf hackery, and I suspect it would take me infinite time to work it
out for myself.

Russell.

Russell Davidson                    email: russell@ehess.cnrs-mrs.fr
GREQAM,
Centre de la Vieille Charite,       telephone: +33-4.91.14.07.40 
F-13002 Marseille                   fax:       +33-4.91.90.02.27