https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118949
--- Comment #4 from Vineet Gupta <vineetg at gcc dot gnu.org> --- Also slightly better test so avoid cpp/installed headers and use bare cc1 void func(const float *a, const float *b, float *c) { for (long i = 0; i < 1024; ++i) { float a_l = __builtin_lround(a[i]); float b_l = __builtin_lround(b[i]); c[i] = a_l + b_l; } }