[clang] [Sema]Use tag name lookup for class names (PR #112166)

[via cfe-commits]

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@@ -7,3 +7,15 @@ namespace PR5840 {
   int Base = 10;
   struct Derived : Base {};
 }
+
+namespace issue_16855 {
+  struct x {};
+  namespace
+  {
+      namespace x
+      {
+          struct y : x
+          {};
+      }
+  }
+}
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Sirraide wrote:

nit: missing newline

https://github.com/llvm/llvm-project/pull/112166