Correct fix to the compile time assert under OW. Kudos to Vadim to the tip.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@30030 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/debug.h

@@ -198,8 +198,17 @@
 
  It may be used both within a function and in the global scope.
 */
-#define wxCOMPILE_TIME_ASSERT(expr, msg) \
-    struct wxMAKE_UNIQUE_ASSERT_NAME { unsigned int msg: expr; }
+#ifdef __WATCOMC__
+    /* avoid "unused symbol" warning */
+    #define wxCOMPILE_TIME_ASSERT(expr, msg) \
+        class wxMAKE_UNIQUE_ASSERT_NAME { \
+          unsigned int msg: expr; \
+          wxMAKE_UNIQUE_ASSERT_NAME(){wxUnusedVar(msg);} \
+        }
+#else
+    #define wxCOMPILE_TIME_ASSERT(expr, msg) \
+        struct wxMAKE_UNIQUE_ASSERT_NAME { unsigned int msg: expr; }
+#endif
 
 
 /* for compatibility only, don't use any more, not needed */