[libunwind] [libunwind] Enable wasm target for exceptions (PR #168449)

[Heejin Ahn via cfe-commits]

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@@ -75,13 +75,14 @@
   #define _LIBUNWIND_EXPORT
   #define _LIBUNWIND_HIDDEN
 #else
-  #if !defined(__ELF__) && !defined(__MACH__) && !defined(_AIX)
-    #define _LIBUNWIND_EXPORT __declspec(dllexport)
-    #define _LIBUNWIND_HIDDEN
-  #else
-    #define _LIBUNWIND_EXPORT __attribute__((visibility("default")))
-    #define _LIBUNWIND_HIDDEN __attribute__((visibility("hidden")))
-  #endif
+#if !defined(__ELF__) && !defined(__MACH__) && !defined(_AIX) &&               \
+    !defined(__wasm__)
+#define _LIBUNWIND_EXPORT __declspec(dllexport)
+#define _LIBUNWIND_HIDDEN
+#else
+#define _LIBUNWIND_EXPORT __attribute__((visibility("default")))
+#define _LIBUNWIND_HIDDEN __attribute__((visibility("hidden")))
+#endif
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aheejin wrote:

Why is this necessary?

https://github.com/llvm/llvm-project/pull/168449