[clang] [C23] More improved type compatibility for enumerations (PR #150946)

[Aaron Ballman via cfe-commits]

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@@ -0,0 +1,16 @@
+// RUN: %clang_cc1 -std=c23 -emit-pch -o %t.1.ast %S/Inputs/enum3.c
+// RUN: %clang_cc1 -std=c23 -emit-pch -o %t.2.ast %S/Inputs/enum4.c
+// RUN: not %clang_cc1 -std=c23 -ast-merge %t.1.ast -ast-merge %t.2.ast -fsyntax-only %s 2>&1 | FileCheck %s
+
+// FIXME: this error should not happen!
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AaronBallman wrote:

I have a fix for this FIXME; once these changes land, I'll post the PR for it so I can reuse this test for coverage.

https://github.com/llvm/llvm-project/pull/150946