[clang] [clang][Diagnostic] Clarify error message for auto (PR #149781)

[Oliver Hunt via cfe-commits]

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@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s
+
+void foo() {
+  struct Local {
+    template <typename T> // expected-error {{member templates are not allowed inside local classes}}
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ojhunt wrote:

Given the original issue, there should be a test for a function with auto parameters, etc - that will let us verify the error message is good/clear for the auto case as well

https://github.com/llvm/llvm-project/pull/149781