Suppress unreachable code warning in unwind tests

git-svn-id: https://llvm.org/svn/llvm-project/libcxxabi/trunk@290487 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/unwind_05.pass.cpp b/test/unwind_05.pass.cpp
index 3dea2aa..df1e429 100644
--- a/test/unwind_05.pass.cpp
+++ b/test/unwind_05.pass.cpp
@@ -13,6 +13,10 @@
 #include <stdlib.h>
 #include <assert.h>
 
+#if defined(__GNUC__)
+#pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+
 struct A
 {
     static int count;