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

[Erich Keane via cfe-commits]

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@@ -401,6 +401,12 @@ struct PragmaMaxTokensTotalHandler : public PragmaHandler {
                     Token &FirstToken) override;
 };
 
+struct PragmaExportHandler : public PragmaHandler {
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erichkeane wrote:

This patch is big enough... I am beginning to wonder if we should split this pragma off into a separate patch.

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