On 05.04.2018 02:54, Richard Henderson wrote: > On 04/05/2018 10:07 AM, Richard Henderson wrote: >> On 04/05/2018 02:49 AM, Emilio G. Cota wrote: >>> 1. grab this binary: >>> http://cs.columbia.edu/~cota/qemu/nbench-aarch64 >>> 2. run it on a PowerPC host with: >>> $ aarch64-linux-user/qemu-aarch64 nbench-aarch64 -V >>> >>> Note: the "-V" (or "-v") flag is important! Without it, there's no segfault. >> >> How quickly? I did not see one up until it exited for lack of NNET.DAT. >> >> I will note that I am using gcc 7.2 on gcc112 >> (/opt/cfarm/gcc-latest/bin/gcc). >> >> Are you using gcc 4.8.5, and is commit 74912f6dad in your tree? >> That commit might have made a difference... > > Bah. I confirm that it doesn't, and that the test still fails. > > Since qemu does work on the same host when built with gcc 7.2, I can only > blame > this failure on a compiler bug wrt gcc 4.8 on ppc64. > > I have not tracked down exactly what's going wrong, and probably won't unless > someone feels that it's worthwhile. This only begs the question of whether we > should blacklist this compiler entirely. Certainly it's old enough that it's > probably not worth fixing.
GCC 4.8 is still used in enterprise distros like RHEL7 and AFAIK also in SLES 12 ... so blacklisting this compiler does not sound like a good idea to me. Thomas