Fix PR clang/3175: CheckAddressOfOperand does not handle references to class vars

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@60849 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index a36bcf5..8cbbca3 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -2876,8 +2876,11 @@
           << "register variable" << op->getSourceRange();
         return QualType();
       }
-    } else if (isa<OverloadedFunctionDecl>(dcl))
+    } else if (isa<OverloadedFunctionDecl>(dcl)) {
       return Context.OverloadTy;
+    } else if (isa<FieldDecl>(dcl)) {
+      // Okay: we can take the address of a field.
+    }
     else 
       assert(0 && "Unknown/unexpected decl type");
   }