[clang] [clang][test] Add test for comma operator rejection in preprocessor conditionals (PR #155570)

[NohHyeon Kwon via cfe-commits]

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@@ -0,0 +1,38 @@
+// RUN: %clang_cc1 -E -pedantic-errors %s -verify -std=c++98
+// RUN: %clang_cc1 -E -pedantic-errors %s -verify -std=c++11
+// RUN: %clang_cc1 -E -pedantic-errors %s -verify -std=c++14
+// RUN: %clang_cc1 -E -pedantic-errors %s -verify -std=c++17
+// RUN: %clang_cc1 -E -pedantic-errors %s -verify -std=c++20
+// RUN: %clang_cc1 -E -pedantic-errors %s -verify -std=c++23
+
+// Test 1: Top-level comma
+// expected-error at +1 {{expected end of line in preprocessor expression}}
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swote-git wrote:

https://github.com/llvm/llvm-project/issues/160152

I opened Issue. 

https://github.com/llvm/llvm-project/pull/155570