QEMU emulation of fmadds instruction on powerpc64le is buggy The attached program test-fmadds.c tests the fmadds instruction on powerpc64le. Result on real hardware (POWER8E processor): $ ./a.out ; echo $? 0 Result in Alpine Linux 3.13/powerpcle, emulated by QEMU 5.0.0 on Ubuntu 16.04: $ ./a.out ; echo $? 32 Result in Debian 8.6.0/ppc64el, emulated by QEMU 2.9.0 on Ubuntu 16.04: $ ./a.out ; echo $? 32 Through 'nm --dynamic qemu-system-ppc64 | grep fma' I can see that QEMU is NOT using the fmaf() or fma() function from the host system's libc; this function is working fine in glibc of the host system (see https://www.gnu.org/software/gnulib/manual/html_node/fmaf.html ).