1 /* { dg-do compile } */
2 /* { dg-options "-O2 -ftree-tail-merge -fdump-tree-pre" } */
20 /* { dg-final { scan-tree-dump-times "duplicate of" 1 "pre"} } */
21 /* { dg-final { scan-tree-dump-times "z = 5" 1 "pre"} } */
22 /* { dg-final { cleanup-tree-dump "pre" } } */