[clang] [Clang] Only compare template params of potential overload after checking their decl context (PR #78139)

[Chuanqi Xu via cfe-commits]

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@@ -0,0 +1,28 @@
+// From https://github.com/llvm/llvm-project/issues/77953
+// RUN: rm -rf %t
+// RUN: mkdir -p %t
+// RUN: split-file %s %t
+
+// RUN: %clang_cc1 -std=c++20 -emit-module-interface %t/a.cppm -o %t/a.pcm
+// RUN: %clang_cc1 -std=c++20 -fmodule-file=a=%t/a.pcm %t/b.cppm
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ChuanqiXu9 wrote:

nit: `%clang_cc1 -std=c++20 -fmodule-file=a=%t/a.pcm %t/b.cpp -fsyntax-only -verify`

I didn't look this in time. I'll try to improve this in a seperate NFC commit.

https://github.com/llvm/llvm-project/pull/78139