g77 internal compiler error

[George Helffrich +44 117 954 5437]

This slightly unusual but extremely simple Fortran program generates an
internal compiler error.  The problem only arises with complex
arithmetic - real works OK.  Expression simplification seems to be
the culprit based on my look into emit-rtl.c.  Here is all the
information to reproduce it:

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#cat /tmp/test.f
      COMPLEX C1,C2

      C1=(1.,0.)
      C2=C1+C1
      END

#f77 -v -c /tmp/test.f
Reading specs from /usr/local/lib/gcc/powerpc-apple-darwin6.6/3.4/specs
Configured with: ../gcc-3.4-20030806/configure --prefix=/usr/local --enable-languages=f77 --infodir=/usr/local/share/info : (reconfigured)
../gcc-3.4-20030806/configure --prefix=/usr/local --enable-languages=c,f77 --infodir=/usr/local/share/info --with-gcc-version-trigger=/usr/local/src/gcc-3.4-20030806/gcc/version.c
Thread model: posix
gcc version 3.4 20030806 (experimental)
 /usr/local/libexec/gcc/powerpc-apple-darwin6.6/3.4/f771 /tmp/test.f -fPIC -quiet -dumpbase test.f -auxbase test -version -o /var/tmp//cck5o3kO.s
GNU F77 version 3.4 20030806 (experimental) (powerpc-apple-darwin6.6)
        compiled by GNU C version 3.4 20030806 (experimental).
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
/tmp/test.f: In program `MAIN__':
In file included from /tmp/test.f:0:
/tmp/test.f:4: internal compiler error: in gen_lowpart, at emit-rtl.c:1374
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://gcc.gnu.org/bugs.html> for instructions.

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                                       George Helffrich
                                       (george@geology.bristol.ac.uk)