XRay-aarch64-linux::patching-unpatching.cc test flaky

[Renato Golin via llvm-commits]

On 1 December 2016 at 11:18, x y <serge.rogatch at gmail.com> wrote:
> I start looking at it today. I guess it could be some UB as we saw
> occasional failure of another AArch64 XRay test earlier:
> http://lab.llvm.org:8011/builders/clang-native-aarch64-full/builds/69 .
> I don't know how to disable a test except XFAIL, but that is only good for
> consistently failing tests.

There are many ways this can be disabled, but the one we used for the
sanitizers was to create a "stable-runtime" flag on the lig.cfg files
and add to the flaky tests:

// REQUIRES: stable-runtime

Basically, "stable-runtime" was set if the arch wasn't "arm". Since
XRay's support for AArch64 and ARM is experimental, we could make the
same assumption and copy the lit.cfg behaviour until you fix all the
issues.

For context, see: https://llvm.org/bugs/show_bug.cgi?id=31074

cheers,
--renato