[llvm] [orc-rt] Implement Windows target triple detection (PR #224514)

[Lang Hames via llvm-commits]

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@@ -65,8 +65,12 @@
 
    TODO: Add the Windows __declspec(dllexport) / __declspec(dllimport) and
    static-build cases once there is a shared-library build to exercise them. */
-#if defined(__has_attribute) && __has_attribute(visibility)
+#if defined(_WIN32)
+#define ORC_RT_C_EXPORT
+#elif defined(__has_attribute) && __has_attribute(visibility)
 #define ORC_RT_C_EXPORT __attribute__((visibility("default")))
+#else
+#define ORC_RT_C_EXPORT
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lhames wrote:

Is this needed? I'd have thought this would reduce via the else case already?

https://github.com/llvm/llvm-project/pull/224514