[clang] [SystemZ][z/OS] Add visibility features for z/OS (eg. _Export, pragma export) (PR #111035)

[Aaron Ballman via cfe-commits]

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@@ -0,0 +1,12 @@
+// REQUIRES: systemz-registered-target
+// RUN: %clang_cc1 -emit-llvm -triple s390x-none-zos -fvisibility=hidden %s -o - | FileCheck %s
+// expected-no-diagnostics
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AaronBallman wrote:

There's no `-verify` line, so this comment doesn't do anything and can be removed.

https://github.com/llvm/llvm-project/pull/111035