[clang] [clang] Avoid inheriting [[noreturn]] in explicit function template specializations (PR #150003)

[Corentin Jabot via cfe-commits]

================
@@ -3267,6 +3267,14 @@ void Sema::mergeDeclAttributes(NamedDecl *New, Decl *Old,
     if (isa<UsedAttr>(I) || isa<RetainAttr>(I))
       continue;
 
+    if (isa<InferredNoReturnAttr>(I)) {
+      if (auto *FD = dyn_cast<FunctionDecl>(New)) {
+        if (FD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization)
----------------
cor3ntin wrote:

```suggestion
      if (auto *FD = dyn_cast<FunctionDecl>(New); FD && FD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization)
```

https://github.com/llvm/llvm-project/pull/150003