[clang] [Clang] Fix segmentation fault caused by `VarBypassDetector` stack overflow on deeply nested expressions (PR #124128)

[Ilya Biryukov via cfe-commits]

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@@ -0,0 +1,30 @@
+// RUN: %clang_cc1 %s -emit-llvm -o - -Wstack-exhausted
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ilya-biryukov wrote:

Flagging to remove this before merging since you say it's too slow.
(You've mentioned that in the description too)


PS we could probably add some build flag to optionally enable slow tests like this and set up a buildbot that runs them for all submitted changes.
It's not great, but better than nothing. 
The suggestion is unrelated to this PR, just thinking out loud here. 

https://github.com/llvm/llvm-project/pull/124128