[Concepts] Add regression test for #99036

[falbrechtskirchinger]

Add a test case for the assertion error encountered in #99036 and #109354. The issue was incidentally fixed by #111179.

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@llvm/pr-subscribers-clang

Author: Florian Albrechtskirchinger (falbrechtskirchinger)

Changes

Add a test case for the assertion error encountered in #99036 and #109354. The issue was incidentally fixed by #111179.

---

Full diff: https://github.com/llvm/llvm-project/pull/113137.diff

1 Files Affected:

• (modified) clang/test/PCH/cxx2a-constraints-crash.cpp (+11-4)

diff --git a/clang/test/PCH/cxx2a-constraints-crash.cpp b/clang/test/PCH/cxx2a-constraints-crash.cpp
index 637c55f0c879c9..5c54ba4c425465 100644
--- a/clang/test/PCH/cxx2a-constraints-crash.cpp
+++ b/clang/test/PCH/cxx2a-constraints-crash.cpp
@@ -1,7 +1,5 @@
-// RUN: %clang_cc1 -std=c++2a -emit-pch %s -o %t
-// RUN: %clang_cc1 -std=c++2a -include-pch %t -verify %s
-
-// expected-no-diagnostics
+// RUN: %clang_cc1 -std=c++2a -fallow-pch-with-compiler-errors -emit-pch -o %t %s -verify
+// RUN: %clang_cc1 -std=c++2a -fallow-pch-with-compiler-errors -include-pch %t %s -verify
 
 #ifndef HEADER
 #define HEADER
@@ -27,3 +25,12 @@ int main() {
 }
 
 #endif
+
+namespace GH99036 {
+
+template <typename T>
+concept C; // expected-error {{expected '='}}
+
+template <C U> void f();
+
+} // namespace GH99036

[falbrechtskirchinger]

@cor3ntin @zyn0217, please review. This is just the test case from #110496. Thanks!

[zyn0217]

LGTM, thanks

(I still would like to see @cor3ntin confirm if it is feasible to backport #103867 to 19 so the issue you're suffering from can be resolved without adding much churn)

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