[clang] [clang] Preserve ext_vector_type locations during template substitution (PR #229328)

[Yanzuo Liu via cfe-commits]

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@@ -525,7 +525,16 @@ class ASTNodeTraverser
     Visit(TL.getSizeExpr());
   }
   void VisitDependentSizedExtVectorTypeLoc(DependentSizedExtVectorTypeLoc TL) {
-    Visit(cast<DependentSizedExtVectorType>(TL.getType())->getSizeExpr());
+    Expr *Size = TL.getSizeExpr();
+    Visit(Size ? Size : TL.getTypePtr()->getSizeExpr());
+  }
+  void VisitVectorTypeLoc(VectorTypeLoc TL) {
+    if (Expr *Size = TL.getSizeExpr())
+      Visit(Size);
+  }
+  void VisitDependentVectorTypeLoc(DependentVectorTypeLoc TL) {
+    Expr *Size = TL.getSizeExpr();
+    Visit(Size ? Size : TL.getTypePtr()->getSizeExpr());
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zwuis wrote:

When is `TL.getSizeExpr()` null but `TL.getTypePtr()->getSizeExpr()` isn't?

https://github.com/llvm/llvm-project/pull/229328