Adding a test case that I accidentally dropped from 27ea7d0

Author: AaronBallman

clang/test/Parser/attr-availability-xcore.c

@@ -0,0 +1,11 @@
+// Test availability message string type when wide characters are 1 byte.
+// REQUIRES: xcore-registered-target
+// RUN: %clang_cc1 -triple xcore -fsyntax-only -verify %s
+
+#if !__has_feature(attribute_availability)
+#  error 'availability' attribute is not available
+#endif
+
+void f7() __attribute__((availability(macosx,message=L"wide"))); // expected-error {{expected string literal for optional message in 'availability' attribute}}
+
+void f8() __attribute__((availability(macosx,message="a" L"b"))); // expected-error {{expected string literal for optional message in 'availability' attribute}}