[clang] [SystemZ][z/OS] Implement #pragma export (PR #141671)

[Erich Keane via cfe-commits]

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@@ -2278,6 +2278,39 @@ class Sema final : public SemaBase {
   ActOnPragmaMSFunction(SourceLocation Loc,
                         const llvm::SmallVectorImpl<StringRef> &NoBuiltins);
 
+  /// A label from a C++ #pragma export, for a symbol that we
+  /// haven't seen the declaration for yet. The TypeList is the argument list
+  /// the function must match if HasTypeList is true.
+  struct SymbolLabel {
+    std::optional<SmallVector<QualType, 4>> TypeList;
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erichkeane wrote:

```suggestion
    std::optional<SmallVector<QualType>> TypeList;
```

https://github.com/llvm/llvm-project/pull/141671