https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82045
--- Comment #1 from rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.org> --- Could you attach the .i file? Using a cross compiler, I was able to build the parts of libgcc that don't depend on system headers, and _multc3.o built OK for me. But that probably isn't indicative of what happens on real Solaris.