Teach CFGBuilder that the 'default' branch of a switch statement is dead if all enum values in a switch conditioned are handled.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@127727 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 13 insertions, 0 deletions

diff --git a/test/SemaCXX/array-bounds.cpp b/test/SemaCXX/array-bounds.cpp
index 62b4d520cc..3bd6c35420 100644
--- a/test/SemaCXX/array-bounds.cpp
+++ b/test/SemaCXX/array-bounds.cpp
@@ -160,3 +160,16 @@ void test_nested_switch()
   }
 }
 
+// Test that if all the values of an enum covered, that the 'default' branch
+// is unreachable.
+enum Values { A, B, C, D };
+void test_all_enums_covered(enum Values v) {
+  int x[2];
+  switch (v) {
+  case A: return;
+  case B: return;
+  case C: return;
+  case D: return;
+  }
+  x[2] = 0; // no-warning
+}