diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index ab552be3bb0de7fb5c4e82184002d9d37745d9be..939bea1d9f9ac3fb8b624f25ff9ddc79cf599e54 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2012-07-06  Tom de Vries  <tom@codesourcery.com>
+
+	PR tree-optimization/51879
+	* gcc.dg/pr51879-16.c: New test.
+	* gcc.dg/pr51879-17.c: Same.
+
 2012-07-06  Tom de Vries  <tom@codesourcery.com>
 
 	PR tree-optimization/52009
diff --git a/gcc/testsuite/gcc.dg/pr51879-16.c b/gcc/testsuite/gcc.dg/pr51879-16.c
new file mode 100644
index 0000000000000000000000000000000000000000..3a84e9746933355be423dfa1272f323f0faa985d
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr51879-16.c
@@ -0,0 +1,32 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-pre" } */
+
+struct S {
+  int i;
+};
+
+extern struct S foo (void);
+extern int foo2 (void);
+
+struct S s;
+
+int bar (int c) {
+  int r;
+
+  if (c)
+    {
+      s = foo ();
+      r = foo2 ();
+    }
+  else
+    {
+      s = foo ();
+      r = foo2 ();
+    }
+
+  return r;
+}
+
+/* { dg-final { scan-tree-dump-times "foo \\(" 1 "pre"} } */
+/* { dg-final { scan-tree-dump-times "foo2 \\(" 1 "pre"} } */
+/* { dg-final { cleanup-tree-dump "pre" } } */
diff --git a/gcc/testsuite/gcc.dg/pr51879-17.c b/gcc/testsuite/gcc.dg/pr51879-17.c
new file mode 100644
index 0000000000000000000000000000000000000000..806fe7b0f61a76934d27a39d207e5c1fc329b24a
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr51879-17.c
@@ -0,0 +1,32 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-pre" } */
+
+struct S {
+  int i;
+};
+
+extern struct S foo (void);
+extern int foo2 (void);
+
+struct S s, s2;
+
+int bar (int c) {
+  int r;
+
+  if (c)
+    {
+      s = foo ();
+      r = foo2 ();
+    }
+  else
+    {
+      s2 = foo ();
+      r = foo2 ();
+    }
+
+  return r;
+}
+
+/* { dg-final { scan-tree-dump-times "foo \\(" 2 "pre"} } */
+/* { dg-final { scan-tree-dump-times "foo2 \\(" 2 "pre"} } */
+/* { dg-final { cleanup-tree-dump "pre" } } */