[compiler-rt] [llvm] [test][msan] Precommit tests for vararg improvements (PR #72612)

[Thurston Dang via llvm-commits]

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@@ -0,0 +1,256 @@
+// Check that shadow of retrived value from va_list matches the shadow of passed value.
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thurstond wrote:

Nit: "retrieved"

https://github.com/llvm/llvm-project/pull/72612