[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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+// REQUIRES: systemz-registered-target
+// RUN: %clang_cc1 %s -emit-llvm -fzos-extensions -triple s390x-none-zos -fvisibility=hidden -verify -o - | FileCheck %s
+
+// Testing missing declarations.
+#pragma export(d0) // expected-warning{{failed to resolve '#pragma export' to a declaration}}
+#pragma export(f9) // expected-warning{{failed to resolve '#pragma export' to a declaration}}
+
+// Testing pragma export after decl.
+void f0(void) {}
+static void sf0(void) {} // expected-warning{{#pragma export is applicable to symbols with external linkage only; not applied to 'sf0'}}
+int v0;
+static int s0; // expected-warning{{#pragma export is applicable to symbols with external linkage only; not applied to 's0'}}
+#pragma export(f0)
+#pragma export(sf0)
+#pragma export(v0)
+#pragma export(s0)
+
+// Testing pragma export before decl.
+#pragma export(f1)
+#pragma export(sf1)
+#pragma export(v1)
+#pragma export(s1)
+void f1(void) {}
+static void sf1(void) {} // expected-warning{{#pragma export is applicable to symbols with external linkage only; not applied to 'sf1'}}
+int v1;
+static int s1; // expected-warning{{#pragma export is applicable to symbols with external linkage only; not applied to 's1'}}
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AaronBallman wrote:

These look like they should be testing in Sema rather than in CodeGen.

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