optimization related ICE

[Bruce Korb]

This fails:
> stage1/xgcc -Bstage1/ -B/usr/local/i686-pc-sco3.2v5.0.5/bin/ \
>   -c -DIN_GCC -W -Wall -Wtraditional -Wwrite-strings -Wstrict-prototypes \
>   -Wmissing-prototypes -pedantic -Wno-long-long -O2 -g -O2 -DHAVE_CONFIG_H \
>   -I. -I../../gcc/gcc -I../../gcc/gcc/config -I../../gcc/gcc/../include \
>   ../../gcc/gcc/stmt.c
> ../../gcc/gcc/stmt.c: In function `expand_nl_goto_receiver':
> ../../gcc/gcc/stmt.c:3498: Internal compiler error in `dwarfout_file_scope_decl'
> , at dwarfout.c:5312
> Please submit a full bug report.
> See <URL: http://www.gnu.org/software/gcc/bugs.html > for instructions.
> gmake[2]: *** [stmt.o] Error 1
> gmake[2]: Leaving directory `/tools/gcc/=build/gcc'
> gmake[1]: *** [bootstrap] Error 2
> gmake[1]: Leaving directory `/tools/gcc/=build/gcc'
> gmake: *** [bootstrap] Error 2

See:
> http://gcc.gnu.org/ml/gcc-bugs/2000-06/msg00696.html

This does not:

> stage1/xgcc -Bstage1/ -B/usr/local/i686-pc-sco3.2v5.0.5/bin/ \
>   -c -DIN_GCC -W -Wall -Wtraditional -Wwrite-strings -Wstrict-prototypes \
>   -Wmissing-prototypes -pedantic -Wno-long-long -g -DHAVE_CONFIG_H \
>   -I. -I../../gcc/gcc -I../../gcc/gcc/config -I../../gcc/gcc/../include \
>   ../../gcc/gcc/stmt.c