Tweak STATIC_ASSERT such that there is no warning about an unused
variable when used at block scope.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@15066 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/include/pub_tool_basics.h b/include/pub_tool_basics.h
index aa5ed75..f6f192c 100644
--- a/include/pub_tool_basics.h
+++ b/include/pub_tool_basics.h
@@ -369,7 +369,8 @@
    })
 
 // Poor man's static assert
-#define STATIC_ASSERT(x)  extern int VG_(VG_(VG_(unused)))[(x) ? 1 : -1]
+#define STATIC_ASSERT(x)  extern int VG_(VG_(VG_(unused)))[(x) ? 1 : -1] \
+                                     __attribute__((unused))
 
 #endif /* __PUB_TOOL_BASICS_H */