diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 7897d5c0ece..b608dd1c5e8 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -6171,7 +6171,8 @@ namespace ts {
 
         function resolveStructuredTypeMembers(type: StructuredType): ResolvedType {
             if (!(<ResolvedType>type).members) {
-                setStructuredTypeMembers(type, emptySymbols, emptyArray, emptyArray, undefined, undefined);
+                const earlySymbols = (type.symbol && type.symbol.members) || emptySymbols;
+                setStructuredTypeMembers(type, earlySymbols, emptyArray, emptyArray, undefined, undefined);
                 if (type.flags & TypeFlags.Object) {
                     if ((<ObjectType>type).objectFlags & ObjectFlags.Reference) {
                         resolveTypeReferenceMembers(<TypeReference>type);