[clang] [Cygwin] va_list must be treated like normal Windows (PR #143115)

[Martin Storsjö via cfe-commits]

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@@ -0,0 +1,37 @@
+// RUN: %clang_cc1 -triple x86_64-windows-gnu -emit-llvm < %s | FileCheck %s
+// RUN: %clang_cc1 -triple x86_64-pc-cygwin -emit-llvm < %s | FileCheck %s
+
+// copy ms_abi block only from ../ms_abi.c
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mstorsjo wrote:

Not sure how relevant the comment about where it is copied from is, when looking at the test file in the future. (It's perhaps more relevant as part of the commit message.)

https://github.com/llvm/llvm-project/pull/143115