[clang] [Cygwin] Global symbols should be external by default (PR #139797)

[Martin Storsjö via cfe-commits]

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@@ -2,6 +2,8 @@
 // RUN: %clang_cc1 -triple x86_64-windows-msvc -fms-extensions -emit-llvm -std=c11 -O0 -o - %s | FileCheck %s
 // RUN: %clang_cc1 -triple i686-windows-gnu    -fms-extensions -emit-llvm -std=c11 -O0 -o - %s | FileCheck %s
 // RUN: %clang_cc1 -triple x86_64-windows-gnu  -fms-extensions -emit-llvm -std=c11 -O0 -o - %s | FileCheck %s
+// RUN: %clang_cc1 -triple i686-pc-cygwin      -fms-extensions -emit-llvm -std=c11 -O0 -o - %s | FileCheck %s
+// RUN: %clang_cc1 -triple x86_64-pc-cygwin    -fms-extensions -emit-llvm -std=c11 -O0 -o - %s | FileCheck %s
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mstorsjo wrote:

These changes to this test do work even before this commit, so they're not directly related. So in theory we could also land such changes as a separate test-only patch. In this case it's quite a small extra test so it probably doesn't matter, but may be good to keep in mind in general.

https://github.com/llvm/llvm-project/pull/139797