[clang] [Clang] Allow musttail in noexcept functions when callee is nounwind (PR #190945)

[Eli Friedman via cfe-commits]

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@@ -0,0 +1,20 @@
+// RUN: %clang_cc1 -fcxx-exceptions -fexceptions -emit-llvm %s -triple x86_64-unknown-linux-gnu -o /dev/null -verify
+
+// Musttail in noexcept functions should work when the callee is also noexcept.
+// The EHTerminateScope pushed by noexcept is safe to skip because the callee
+// won't throw.
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efriedma-quic wrote:

For the "negative" case, checking for the error message is sufficient.

For the "positive" case, I'd like to see something like `CHECK: musttail call @NoexceptCallee() noexcept`.

https://github.com/llvm/llvm-project/pull/190945