I could finally make Debian GNU/Linux install and run under qemu-system-ppc64. I used Debian 7.0.0 and qemu from the main git repo, updated a few days ago.
While Debian runs well and not too slowly, GMP fails badly under all ABIs, and in many different ways. I have isolated the first problem. Test case: #include <stdio.h> int main () { unsigned long r; asm ("rldcl\t%0, %1, %2, 0" : "=r" (r) : "r" (0xcafebabedeadbeeful), "r" (16)); printf ("%lx\n", r); return 0; } Expected output: babedeadbeefcafe Output under qemu: 0 I have single stepped in gdb to determine that it is indeed rldcl that misbehaves. -- Torbjörn