https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92772
Andrew Stubbs <ams at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Priority|P3 |P5 Severity|critical |minor --- Comment #7 from Andrew Stubbs <ams at gcc dot gnu.org> --- Thank you for the help, Richard and Richard. I'm electing not to fix this bug, but instead have worked around it for amdgcn by implementing the fold_extract_last pattern. There's two main reasons for this: 1. I'm not confident I can see how to fix it properly, so it's going to take me a long time to get it right. 2. The code that it generates is horrible (and the fix will only make it worse), so I would want to implement fold_extract_last anyway. This would leave this code unused by amdgcn, and the time spent fixing it wasted effort. I've therefore downgraded the priority and severity on this bug, and committed a pointer into the code to assist anybody tripping over the same issue in future. https://gcc.gnu.org/ml/gcc-patches/2019-12/msg01191.html The bug still exists, but is now no longer reproducible on amdgcn.