[llvm] [symbolizer] Empty string is not an error (PR #92660)

[via llvm-commits]

pcc wrote:

It comes up often enough that compiler-rt explicitly tries to detect this case:

https://github.com/llvm/llvm-project/blob/2ba08386156ef25913b1bee170d8fe95aaceb234/compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cpp#L194

It does so by sleeping for 10ms and checking whether the process is still running. But this is clearly racy: 10ms is not necessarily enough time for the child process to reach the point where it would fail. I think there ought to be a non-racy way to do this.

https://github.com/llvm/llvm-project/pull/92660