use COPY_ARRAY

Add a semantic patch for converting certain calls of memcpy(3) to
COPY_ARRAY() and apply that transformation to the code base.  The result
is
 shorter and safer code.  For now only consider calls where source and
destination have the same type, or in other words: easy cases.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

commit.c

@@ -931,7 +931,7 @@ static int remove_redundant(struct commit **array, int cnt)
 	}
 
 	/* Now collect the result */
-	memcpy(work, array, sizeof(*array) * cnt);
+	COPY_ARRAY(work, array, cnt);
 	for (i = filled = 0; i < cnt; i++)
 		if (!redundant[i])
 			array[filled++] = work[i];