[compiler-rt] [TSan] Clarify and enforce shadow end alignment (PR #144648)

[Thurston Dang via llvm-commits]

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@@ -0,0 +1,32 @@
+// RUN: %clangxx_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
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thurstond wrote:

Please add these test cases to a separate pull request. Since your fix is not committed yet, the tests would need an ["XFAIL" annotation](https://llvm.org/docs/TestingGuide.html#constraining-test-execution). Then, after the test cases are landed, this fix PR would update the test by removing the XFAIL. This two-step procedure makes it clear that 1) TSan was broken 2) this PR fixes it.

https://github.com/llvm/llvm-project/pull/144648