https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65341
--- Comment #8 from Martin Sebor <msebor at gcc dot gnu.org> --- (In reply to David Edelsohn from comment #7) I assume the patch you are referring to is r221132 (pr65138). It doesn't look like that's fixed it. The latest trunk exhibits the same problem: $ cat t.s && /build/gcc-trunk-git/gcc/xgcc -B /build/gcc-trunk-git/gcc -dM -E -xc - < /dev/null | grep PWR6 && /build/gcc-trunk-git/gcc/xgcc -B /build/gcc-trunk-git/gcc -c -v t.s .text start: mtfsf 6,10,0,0 #define _ARCH_PWR6 1 Reading specs from /build/gcc-trunk-git/gcc/specs COLLECT_GCC=/build/gcc-trunk-git/gcc/xgcc Target: powerpc64le-unknown-linux-gnu Configured with: /src/gcc-trunk-git/configure --disable-bootstrap --enable-languages=c,c++ Thread model: posix gcc version 5.0.0 20150307 (experimental) (GCC) COLLECT_GCC_OPTIONS='-B' '/build/gcc-trunk-git/gcc' '-c' '-v' /build/gcc-trunk-git/gcc/as -v -a64 -mppc64 -many -mlittle -o t.o t.s GNU assembler version 2.23.52.0.1 (ppc64le-redhat-linux) using BFD version version 2.23.52.0.1-30.ael7b 20130226 t.s: Assembler messages: t.s:3: Error: junk at end of line: `0,0'