[clang] Suppress noreturn warning if last statement in a function is a throw (PR #145166)

[Erich Keane via cfe-commits]

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@@ -681,6 +702,28 @@ static void CheckFallThroughForBody(Sema &S, const Decl *D, const Stmt *Body,
       if (CD.diag_FallThrough_HasNoReturn)
         S.Diag(RBrace, CD.diag_FallThrough_HasNoReturn) << CD.FunKind;
     } else if (!ReturnsVoid && CD.diag_FallThrough_ReturnsNonVoid) {
+      // If the final statement is a call to an always-throwing function,
+      // don't warn about the fall-through.
+      if (const auto *FD = dyn_cast<FunctionDecl>(D)) {
----------------
erichkeane wrote:

```suggestion
      if (const auto *FD = D->getAsFunction()) {
```

https://github.com/llvm/llvm-project/pull/145166