https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78970
--- Comment #2 from Martin Liška <marxin at gcc dot gnu.org> ---
Ok, basic problem is in _cpp_save_file_entries, where we calculate md5sum of
all inputs files. Providing '-' will cause to have input file as fd == 0 and
ff = fdopen (f->fd, "rb");
md5_stream (ff, result->entries[count].sum);
fclose (ff);
will fail as fdopen fails for 0 fd.
Thoughts?
Another corner case is using --save-temps that will also confuse command line:
cc1: error: unrecognized command line option ‘-.i’
./cc1 -fpreprocessed -.i -quiet -dumpbase - -mtune=generic -march=x86-64
-auxbase - -version -o -.s --output-pch= pes.pch
