[compiler-rt] [compiler-rt] Allow building builtins.a without a libc (PR #86737)

[Jon Chesterfield via llvm-commits]

JonChesterfield wrote:

So much for that theory, failed the same way.

Is your buildbot choosing whether to try to build sanitizers based on whether it can built builtins, such that spuriously failing to build builtins without this patch is "success" but successfully building builtins means it tries to build the sanitizers, which it can't, and that failure to build is not ok?

If you don't need sanitizers (presumably true, since it looks like your bot doesn't build them with or without this patch?), can you pass the sanitizers=off flag to cmake?

https://github.com/llvm/llvm-project/pull/86737