[clang] [Clang][P1061] Fix template arguments in local classes (PR #121225)

[Younan Zhang via cfe-commits]

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@@ -0,0 +1,14 @@
+// RUN: %clang_cc1 -fsyntax-only %s -verify
+// expected-no-diagnostics
+
+template <int i>
+int g() {
+  return [] (auto) -> int {
+    struct L {
+      int m = i;
+    };
+    return 0;
+  } (42);
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zyn0217 wrote:

I feel like this is some fallout of not decoupling instantiating lambda body from the lambda transformation. If we had been able to avoid the body transform when transforming the lambda for the call expression, we could also have avoided instantiating an offending intermediate `L`, right? @erichkeane 

https://github.com/llvm/llvm-project/pull/121225