[clang] [clang][NFC] Add test for CWG issues about linkage in cross-TU context (PR #113736)

[via cfe-commits]

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@@ -0,0 +1,42 @@
+// RUN: rm -rf %t
+// RUN: mkdir %t
+// RUN: split-file --leading-lines %s %t
+// RUN: %clang_cc1 -std=c++20 -pedantic-errors -fexceptions -fcxx-exceptions %t/cwg279_A.cppm -triple x86_64-unknown-unknown -emit-module-interface -o %t/cwg279_A.pcm
+// RUN: %clang_cc1 -std=c++20 -verify=since-cxx20 -pedantic-errors -fexceptions -fcxx-exceptions -triple x86_64-unknown-unknown %t/cwg279.cpp -fmodule-file=cwg279_A=%t/cwg279_A.pcm
+// RUN: %clang_cc1 -std=c++23 -pedantic-errors -fexceptions -fcxx-exceptions %t/cwg279_A.cppm -triple x86_64-unknown-unknown -emit-module-interface -o %t/cwg279_A.pcm
+// RUN: %clang_cc1 -std=c++23 -verify=since-cxx20 -pedantic-errors -fexceptions -fcxx-exceptions -triple x86_64-unknown-unknown %t/cwg279.cpp -fmodule-file=cwg279_A=%t/cwg279_A.pcm
+// RUN: %clang_cc1 -std=c++2c -pedantic-errors -fexceptions -fcxx-exceptions %t/cwg279_A.cppm -triple x86_64-unknown-unknown -emit-module-interface -o %t/cwg279_A.pcm
+// RUN: %clang_cc1 -std=c++2c -verify=since-cxx20 -pedantic-errors -fexceptions -fcxx-exceptions -triple x86_64-unknown-unknown %t/cwg279.cpp -fmodule-file=cwg279_A=%t/cwg279_A.pcm
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cor3ntin wrote:

Really no need to test in all language modes something we don't support

https://github.com/llvm/llvm-project/pull/113736