[clang] [LifetimeSafety] Introduce buildOriginFlowChain for use-after-scope (PR #199345)

[Gábor Horváth via cfe-commits]

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@@ -471,13 +474,47 @@ class LifetimeSafetySemaHelperImpl : public LifetimeSafetySemaHelper {
   }
 
   std::string getDiagSubjectDescription(const Expr *E) {
+    E = E->IgnoreImpCasts();
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Xazax-hun wrote:

I wonder if we already have a function somewhere that enumerates all the node types that we usually skip, and that might include some more like parentheses. If that is the case maybe we should reuse that?

https://github.com/llvm/llvm-project/pull/199345