I can't be sure of the cause but I believe these fail
due to to fast unwinding not working on Thumb.
Whatever the case, they have been failing on our bots
for a long time:
https://lab.llvm.org/buildbot/#/builders/170/builds/46
Require fast-unwinder-works for both.
See https://llvm.org/PR46862. This does not fix the underlying issue but at
least it allows me to run check-all again without having to disable
building compiler-rt.
Reviewed By: #sanitizers, vitalybuka
Differential Revision: https://reviews.llvm.org/D84650
