Vendor things

third-party/vendor/objc_exception/extern/exception.m

@@ -0,0 +1,21 @@
+#include <objc/objc.h>
+#include <objc/NSObject.h>
+
+void RustObjCExceptionThrow(id exception) {
+    @throw exception;
+}
+
+int RustObjCExceptionTryCatch(void (*try)(void *), void *context, id *error) {
+    @try {
+        try(context);
+        if (error) {
+            *error = nil;
+        }
+        return 0;
+    } @catch (id exception) {
+        if (error) {
+            *error = [exception retain];
+        }
+        return 1;
+    }
+}