[clang] [clang][analyzer] Fix a crash in alpha.unix.BlockInCriticalSection (PR #90030)

[Balazs Benics via cfe-commits]

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@@ -103,9 +104,10 @@ class RAIIMutexDescriptor {
       // this function is called instead of early returning it. To avoid this, a
       // bool variable (IdentifierInfoInitialized) is used and the function will
       // be run only once.
-      Guard = &Call.getCalleeAnalysisDeclContext()->getASTContext().Idents.get(
-          GuardName);
-      IdentifierInfoInitialized = true;
+      if (AnalysisDeclContext *CalleCtx = Call.getCalleeAnalysisDeclContext()) {
+        Guard = &CalleCtx->getASTContext().Idents.get(GuardName);
+        IdentifierInfoInitialized = true;
+      }
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steakhal wrote:

This crash happened because we failed to get an ASTContext.
Maybe, on some other access-path we could acquire the ASTContext, like via `Call.getState()->getStateManager().getContext()`.

I feel like your proposal only fixes the symptom, and not the root cause.

https://github.com/llvm/llvm-project/pull/90030