[clang] [Clang] Prevent potential null pointer dereferences (PR #117176)

[via cfe-commits]

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@@ -627,7 +627,7 @@ class Analyzer {
           IsNoexcept = isNoexcept(FD);
         } else if (auto *BD = dyn_cast<BlockDecl>(D)) {
           if (auto *TSI = BD->getSignatureAsWritten()) {
-            auto *FPT = TSI->getType()->getAs<FunctionProtoType>();
+            auto *FPT = TSI->getType()->castAs<FunctionProtoType>();
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Sirraide wrote:

> are K&R C functions supposed to support function effects?

They should yes; we had to add checks for functions w/o prototypes in several places to avoid crashes.

https://github.com/llvm/llvm-project/pull/117176