https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102059
--- Comment #21 from Chip Kerchner <chip.kerchner at ibm dot com> --- I'm also seeing MMA problems with LTO. With this simple program (main.ii) ---------------------- int main() { float *b; __vector_quad c; __builtin_mma_disassemble_acc(b, &c); return 0; } ---------------------- And this compile (using gcc 10.3.1) ---------------------- g++ -flto=auto -mcpu=power9 main.ii ---------------------- I'm seeing this error (which does NOT occur without LTO) ---------------------- lto1: error: '__builtin_mma_xxmfacc_internal' requires the '-mmma' option lto1: fatal error: target specific builtin not available compilation terminated. ----------------------