Description of problem: What it says on the box. This is known upstream (though not in the release notes), and it makes the Mesa software renderer explode when used on Sandybridge CPUs. Simplest fix for F15 is to disable AVX code generation. I have a patch for this. Version-Release number of selected component (if applicable): 2.8-10.fc15
Upstream bug reference, for the curious: http://llvm.org/bugs/show_bug.cgi?id=9508
llvm-2.8-11.fc15 has been submitted as an update for Fedora 15. https://admin.fedoraproject.org/updates/llvm-2.8-11.fc15
Package llvm-2.8-11.fc15: * should fix your issue, * was pushed to the Fedora 15 testing repository, * should be available at your local mirror within two days. Update it with: # su -c 'yum update --enablerepo=updates-testing llvm-2.8-11.fc15' as soon as you are able to. Please go to the following url: https://admin.fedoraproject.org/updates/llvm-2.8-11.fc15 then log in and leave karma (feedback).
Discussed at the 2011-04-29 blocker review meeting. Accepted as a blocker under criterion "# Following on from the previous criterion, after firstboot is completed and on subsequent boots, a system installed according to any of the above criteria (or the appropriate Beta or Final criteria, when applying this criterion to those releases) must boot to a working graphical environment without unintended user intervention. This includes correctly accessing any encrypted partitions when the correct passphrase is supplied "; this could cause catastrophic desktop failure in certain circumstances. -- Fedora Bugzappers volunteer triage team https://fedoraproject.org/wiki/BugZappers
llvm-2.8-11.fc15 has been pushed to the Fedora 15 stable repository. If problems still persist, please make note of it in this bug report.