1 files changed, 21 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr21658.c b/gcc/testsuite/gcc.dg/tree-ssa/pr21658.c
new file mode 100644
index 000000000..c1a48c04b
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr21658.c
@@ -0,0 +1,21 @@
+/* PR tree-optimization/21658
+   CCP did not propagate an ADDR_EXPR far enough, preventing the "if"
+   statement below from being folded.  */
+
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-tree-dominator-opts -fdump-tree-ccp1-details" } */
+
+void link_error (void);
+
+void
+f (void)
+{
+  int a[10];
+  int *p = &a[5];
+  int *q = p - 1;
+  if (q != &a[4])
+    link_error ();
+}
+
+/* { dg-final { scan-tree-dump-times "Folded into: if " 1 "ccp1"} } */
+/* { dg-final { cleanup-tree-dump "ccp1" } } */