diff --git a/hlsl/hlslGrammar.cpp b/hlsl/hlslGrammar.cpp
index 88eacd9..515922e 100755
--- a/hlsl/hlslGrammar.cpp
+++ b/hlsl/hlslGrammar.cpp
@@ -2426,6 +2426,9 @@
         node = parseContext.handleFunctionCall(token.loc, constructor, node);
     }
 
+    if (node == nullptr)
+        return false;
+
     // If this is simply a constant, we can use it directly.
     if (node->getAsConstantUnion())
         return true;
@@ -2862,7 +2865,7 @@
                 parseContext.handleFunctionArgument(constructorFunction, arguments, node);
                 node = parseContext.handleFunctionCall(loc, constructorFunction, arguments);
 
-                return true;
+                return node != nullptr;
             } else {
                 // This could be a parenthesized constructor, ala (int(3)), and we just accepted
                 // the '(int' part.  We must back up twice.
@@ -3072,7 +3075,7 @@
         // hook it up
         node = parseContext.handleFunctionCall(arguments->getLoc(), constructorFunction, arguments);
 
-        return true;
+        return node != nullptr;
     }
 
     return false;
@@ -3120,7 +3123,7 @@
     // call
     node = parseContext.handleFunctionCall(loc, function, arguments);
 
-    return true;
+    return node != nullptr;
 }
 
 // arguments
diff --git a/hlsl/hlslParseHelper.cpp b/hlsl/hlslParseHelper.cpp
index a336bd7..706173d 100755
--- a/hlsl/hlslParseHelper.cpp
+++ b/hlsl/hlslParseHelper.cpp
@@ -4981,8 +4981,10 @@
             // It's a constructor, of type 'type'.
             //
             result = handleConstructor(loc, arguments, type);
-            if (result == nullptr)
+            if (result == nullptr) {
                 error(loc, "cannot construct with these arguments", type.getCompleteString().c_str(), "");
+                return nullptr;
+            }
         }
     } else {
         //
@@ -7736,6 +7738,14 @@
 
         return addConstructor(loc, initList, arrayType);
     } else if (type.isStruct()) {
+        // do we have implicit assignments to opaques?
+        for (size_t i = initList->getSequence().size(); i < type.getStruct()->size(); ++i) {
+            if ((*type.getStruct())[i].type->containsOpaque()) {
+                error(loc, "cannot implicitly initialize opaque members", "initializer list", "");
+                return nullptr;
+            }
+        }
+
         // lengthen list to be long enough
         lengthenList(loc, initList->getSequence(), static_cast<int>(type.getStruct()->size()), scalarInit);