[clang] Add a "don't override" mapping for -fvisibility-from-dllstorageclass (PR #74629)

[Paul T Robinson via cfe-commits]

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@@ -79,6 +107,8 @@ extern void __declspec(dllimport) imported_e();
 // EXPLICIT-DAG: declare hidden void @_Z10imported_ev()
 // ALL_DEFAULT-DAG: declare void @_Z1ev()
 // ALL_DEFAULT-DAG: declare void @_Z10imported_ev()
+// ALL_KEEP-DAG: declare hidden void @_Z1ev()
+// ALL_KEEP-DAG: void @_Z10imported_ev()
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pogo59 wrote:

Oh, this line looks like it would allow any visibility (missing `declare` and whatever might be between that and the `void`)

https://github.com/llvm/llvm-project/pull/74629