[analyzer] Tighten up safety in the use of lazy bindings.

- When deciding if we can reuse a lazy binding, make sure to check if there
  are additional bindings in the sub-region.
- When reading from a lazy binding, don't accidentally strip off casts or
  base object regions. This slows down lazy binding reading a bit but is
  necessary for type sanity when treating one class as another.

A bit of minor refactoring allowed these two checks to be unified in a nice
early-return-using helper function.

<rdar://problem/13239840>

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175703 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 29 insertions, 0 deletions

diff --git a/test/Analysis/derived-to-base.cpp b/test/Analysis/derived-to-base.cpp
index 80dbc178c4..6e4a3fa87a 100644
--- a/test/Analysis/derived-to-base.cpp
+++ b/test/Analysis/derived-to-base.cpp
@@ -303,4 +303,33 @@ namespace LazyBindings {
     }
 #endif
   }
+
+#if CONSTRUCTORS
+  namespace Nested {
+    struct NonTrivialCopy {
+      int padding;
+      NonTrivialCopy() {}
+      NonTrivialCopy(const NonTrivialCopy &) {}
+    };
+
+    struct FullyDerived : private NonTrivialCopy, public Derived {
+      int z;
+    };
+
+    struct Wrapper {
+      FullyDerived d;
+      int zz;
+
+      Wrapper(const FullyDerived &d) : d(d), zz(0) {}
+    };
+
+    void test5() {
+      Wrapper w((FullyDerived()));
+      w.d.x = 1;
+
+      Wrapper w2(w);
+      clang_analyzer_eval(getX(w2.d) == 1); // expected-warning{{TRUE}}
+    }
+  }
+#endif
 }