Look through chains of 'x = y = z' when employing silencing heuristics in the DeadStoresChecker.

Fixes <rdar://problem/11185138>.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@154040 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 22 insertions, 0 deletions

diff --git a/test/Analysis/dead-stores.c b/test/Analysis/dead-stores.c
index 4c0c1bc130..b8d195d05a 100644
--- a/test/Analysis/dead-stores.c
+++ b/test/Analysis/dead-stores.c
@@ -526,3 +526,25 @@ void rdar8405222() {
     rdar8405222_aux(i);
 }
 
+// Look through chains of assignements, e.g.: int x = y = 0, when employing
+// silencing heuristics.
+int radar11185138_foo() {
+  int x, y;
+  x = y = 0; // expected-warning {{never read}}
+  return y;
+}
+
+int rdar11185138_bar() {
+  int y;
+  int x = y = 0; // no-warning
+  x = 2;
+  y = 2;
+  return x + y;
+}
+
+int *radar11185138_baz() {
+  int *x, *y;
+  x = y = 0; // no-warning
+  return y;
+}
+