Fixed problem with undefined assert symbol

include/m_string.h

@@ -125,9 +125,7 @@ extern	void bmove_allign(gptr dst,const gptr src,uint len);
 DBUG_ASSERT((A) == (B) || ((A)+(C)) <= (B) || ((B)+(C)) <= (A)); \
 bmove((byte*) key,(byte*) from,(size_t) length);
 #else
-#define memcpy_overlap(A,B,C) \
-DBUG_ASSERT((A) == (B) || ((A)+(C)) <= (B) || ((B)+(C)) <= (A)); \
-memcpy((A), (B), (C))
+#define memcpy_overlap(A,B,C) memcpy((A), (B), (C))
 #endif /* HAVE_purify */