diff --git a/lib/tsc.js b/lib/tsc.js
index ca474fc5f0656..447e451186c39 100644
--- a/lib/tsc.js
+++ b/lib/tsc.js
@@ -67,7 +67,7 @@ var __makeTemplateObject = (this && this.__makeTemplateObject) || function (cook
 var ts;
 (function (ts) {
     ts.versionMajorMinor = "3.6";
-    ts.version = ts.versionMajorMinor + ".3";
+    ts.version = ts.versionMajorMinor + ".4";
 })(ts || (ts = {}));
 (function (ts) {
     ts.emptyArray = [];
@@ -7282,7 +7282,7 @@ var ts;
     }
     ts.isEnumConst = isEnumConst;
     function isDeclarationReadonly(declaration) {
-        return !!(ts.getCombinedModifierFlags(declaration) & 64 && !ts.isParameterPropertyDeclaration(declaration));
+        return !!(ts.getCombinedModifierFlags(declaration) & 64 && !ts.isParameterPropertyDeclaration(declaration, declaration.parent));
     }
     ts.isDeclarationReadonly = isDeclarationReadonly;
     function isVarConst(node) {
@@ -10525,8 +10525,8 @@ var ts;
         }
     }
     ts.getTypeParameterOwner = getTypeParameterOwner;
-    function isParameterPropertyDeclaration(node) {
-        return ts.hasModifier(node, 92) && node.parent.kind === 158;
+    function isParameterPropertyDeclaration(node, parent) {
+        return ts.hasModifier(node, 92) && parent.kind === 158;
     }
     ts.isParameterPropertyDeclaration = isParameterPropertyDeclaration;
     function isEmptyBindingPattern(node) {
@@ -25150,7 +25150,7 @@ var ts;
             else {
                 declareSymbolAndAddToSymbolTable(node, 1, 111551);
             }
-            if (ts.isParameterPropertyDeclaration(node)) {
+            if (ts.isParameterPropertyDeclaration(node, node.parent)) {
                 var classDeclaration = node.parent.parent;
                 declareSymbol(classDeclaration.symbol.members, classDeclaration.symbol, node, 4 | (node.questionToken ? 16777216 : 0), 0);
             }
@@ -33247,8 +33247,7 @@ var ts;
             return undefined;
         }
         function getConstraintDeclaration(type) {
-            var decl = type.symbol && ts.getDeclarationOfKind(type.symbol, 151);
-            return decl && ts.getEffectiveConstraintOfTypeParameter(decl);
+            return ts.mapDefined(ts.filter(type.symbol && type.symbol.declarations, ts.isTypeParameterDeclaration), ts.getEffectiveConstraintOfTypeParameter)[0];
         }
         function getInferredTypeParameterConstraint(typeParameter) {
             var inferences;
@@ -33424,11 +33423,11 @@ var ts;
             }
             return undefined;
         }
-        function resolveTypeReferenceName(typeReferenceName, meaning) {
+        function resolveTypeReferenceName(typeReferenceName, meaning, ignoreErrors) {
             if (!typeReferenceName) {
                 return unknownSymbol;
             }
-            return resolveEntityName(typeReferenceName, meaning) || unknownSymbol;
+            return resolveEntityName(typeReferenceName, meaning, ignoreErrors) || unknownSymbol;
         }
         function getTypeReferenceType(node, symbol) {
             var typeArguments = typeArgumentsFromTypeReferenceNode(node);
@@ -33592,7 +33591,16 @@ var ts;
                 var meaning = 788968;
                 if (isJSDocTypeReference(node)) {
                     type = getIntendedTypeFromJSDocTypeReference(node);
-                    meaning |= 111551;
+                    if (!type) {
+                        symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning, true);
+                        if (symbol === unknownSymbol) {
+                            symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning | 111551);
+                        }
+                        else {
+                            resolveTypeReferenceName(getTypeReferenceName(node), meaning);
+                        }
+                        type = getTypeReferenceType(node, symbol);
+                    }
                 }
                 if (!type) {
                     symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning);
@@ -46510,7 +46518,7 @@ var ts;
                 if (member.kind === 158) {
                     for (var _b = 0, _c = member.parameters; _b < _c.length; _b++) {
                         var param = _c[_b];
-                        if (ts.isParameterPropertyDeclaration(param) && !ts.isBindingPattern(param.name)) {
+                        if (ts.isParameterPropertyDeclaration(param, member) && !ts.isBindingPattern(param.name)) {
                             addName(instanceNames, param.name, param.name.escapedText, 3);
                         }
                     }
@@ -47816,7 +47824,7 @@ var ts;
                         var parameter = local.valueDeclaration && tryGetRootParameterDeclaration(local.valueDeclaration);
                         var name = local.valueDeclaration && ts.getNameOfDeclaration(local.valueDeclaration);
                         if (parameter && name) {
-                            if (!ts.isParameterPropertyDeclaration(parameter) && !ts.parameterIsThisKeyword(parameter) && !isIdentifierThatStartsWithUnderscore(name)) {
+                            if (!ts.isParameterPropertyDeclaration(parameter, parameter.parent) && !ts.parameterIsThisKeyword(parameter) && !isIdentifierThatStartsWithUnderscore(name)) {
                                 addDiagnostic(parameter, 1, ts.createDiagnosticForNode(name, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, ts.symbolName(local)));
                             }
                         }
@@ -49050,10 +49058,8 @@ var ts;
                     var constraint = ts.getEffectiveConstraintOfTypeParameter(source);
                     var sourceConstraint = constraint && getTypeFromTypeNode(constraint);
                     var targetConstraint = getConstraintOfTypeParameter(target);
-                    if (sourceConstraint) {
-                        if (!targetConstraint || !isTypeIdenticalTo(sourceConstraint, targetConstraint)) {
-                            return false;
-                        }
+                    if (sourceConstraint && targetConstraint && !isTypeIdenticalTo(sourceConstraint, targetConstraint)) {
+                        return false;
                     }
                     var sourceDefault = source.default && getTypeFromTypeNode(source.default);
                     var targetDefault = getDefaultFromTypeParameter(target);
@@ -59445,7 +59451,7 @@ var ts;
             var members = [];
             var constructor = ts.getFirstConstructorWithBody(node);
             var parametersWithPropertyAssignments = constructor &&
-                ts.filter(constructor.parameters, ts.isParameterPropertyDeclaration);
+                ts.filter(constructor.parameters, function (p) { return ts.isParameterPropertyDeclaration(p, constructor); });
             if (parametersWithPropertyAssignments) {
                 for (var _i = 0, parametersWithPropertyAssignments_1 = parametersWithPropertyAssignments; _i < parametersWithPropertyAssignments_1.length; _i++) {
                     var parameter = parametersWithPropertyAssignments_1[_i];
@@ -59989,7 +59995,7 @@ var ts;
         }
         function transformConstructorBody(body, constructor) {
             var parametersWithPropertyAssignments = constructor &&
-                ts.filter(constructor.parameters, ts.isParameterPropertyDeclaration);
+                ts.filter(constructor.parameters, function (p) { return ts.isParameterPropertyDeclaration(p, constructor); });
             if (!ts.some(parametersWithPropertyAssignments)) {
                 return ts.visitFunctionBody(body, visitor, context);
             }
@@ -60859,7 +60865,7 @@ var ts;
             if (constructor && constructor.body) {
                 var parameterPropertyDeclarationCount = 0;
                 for (var i = indexOfFirstStatement; i < constructor.body.statements.length; i++) {
-                    if (ts.isParameterPropertyDeclaration(ts.getOriginalNode(constructor.body.statements[i]))) {
+                    if (ts.isParameterPropertyDeclaration(ts.getOriginalNode(constructor.body.statements[i]), constructor)) {
                         parameterPropertyDeclarationCount++;
                     }
                     else {
@@ -68314,7 +68320,7 @@ var ts;
             return getReturnTypeVisibilityError;
         }
         else if (ts.isParameter(node)) {
-            if (ts.isParameterPropertyDeclaration(node) && ts.hasModifier(node.parent, 8)) {
+            if (ts.isParameterPropertyDeclaration(node, node.parent) && ts.hasModifier(node.parent, 8)) {
                 return getVariableDeclarationTypeVisibilityError;
             }
             return getParameterDeclarationTypeVisibilityError;
diff --git a/lib/tsserver.js b/lib/tsserver.js
index d23682342368d..be5166a94b4bc 100644
--- a/lib/tsserver.js
+++ b/lib/tsserver.js
@@ -94,7 +94,7 @@ var ts;
     // If changing the text in this section, be sure to test `configureNightly` too.
     ts.versionMajorMinor = "3.6";
     /** The version of the TypeScript compiler release */
-    ts.version = ts.versionMajorMinor + ".3";
+    ts.version = ts.versionMajorMinor + ".4";
 })(ts || (ts = {}));
 (function (ts) {
     /* @internal */
@@ -9711,7 +9711,7 @@ var ts;
     }
     ts.isEnumConst = isEnumConst;
     function isDeclarationReadonly(declaration) {
-        return !!(ts.getCombinedModifierFlags(declaration) & 64 /* Readonly */ && !ts.isParameterPropertyDeclaration(declaration));
+        return !!(ts.getCombinedModifierFlags(declaration) & 64 /* Readonly */ && !ts.isParameterPropertyDeclaration(declaration, declaration.parent));
     }
     ts.isDeclarationReadonly = isDeclarationReadonly;
     function isVarConst(node) {
@@ -13420,8 +13420,8 @@ var ts;
         }
     }
     ts.getTypeParameterOwner = getTypeParameterOwner;
-    function isParameterPropertyDeclaration(node) {
-        return ts.hasModifier(node, 92 /* ParameterPropertyModifier */) && node.parent.kind === 158 /* Constructor */;
+    function isParameterPropertyDeclaration(node, parent) {
+        return ts.hasModifier(node, 92 /* ParameterPropertyModifier */) && parent.kind === 158 /* Constructor */;
     }
     ts.isParameterPropertyDeclaration = isParameterPropertyDeclaration;
     function isEmptyBindingPattern(node) {
@@ -30762,7 +30762,7 @@ var ts;
             }
             // If this is a property-parameter, then also declare the property symbol into the
             // containing class.
-            if (ts.isParameterPropertyDeclaration(node)) {
+            if (ts.isParameterPropertyDeclaration(node, node.parent)) {
                 var classDeclaration = node.parent.parent;
                 declareSymbol(classDeclaration.symbol.members, classDeclaration.symbol, node, 4 /* Property */ | (node.questionToken ? 16777216 /* Optional */ : 0 /* None */), 0 /* PropertyExcludes */);
             }
@@ -40120,8 +40120,7 @@ var ts;
             return undefined;
         }
         function getConstraintDeclaration(type) {
-            var decl = type.symbol && ts.getDeclarationOfKind(type.symbol, 151 /* TypeParameter */);
-            return decl && ts.getEffectiveConstraintOfTypeParameter(decl);
+            return ts.mapDefined(ts.filter(type.symbol && type.symbol.declarations, ts.isTypeParameterDeclaration), ts.getEffectiveConstraintOfTypeParameter)[0];
         }
         function getInferredTypeParameterConstraint(typeParameter) {
             var inferences;
@@ -40329,11 +40328,11 @@ var ts;
             }
             return undefined;
         }
-        function resolveTypeReferenceName(typeReferenceName, meaning) {
+        function resolveTypeReferenceName(typeReferenceName, meaning, ignoreErrors) {
             if (!typeReferenceName) {
                 return unknownSymbol;
             }
-            return resolveEntityName(typeReferenceName, meaning) || unknownSymbol;
+            return resolveEntityName(typeReferenceName, meaning, ignoreErrors) || unknownSymbol;
         }
         function getTypeReferenceType(node, symbol) {
             var typeArguments = typeArgumentsFromTypeReferenceNode(node); // Do unconditionally so we mark type arguments as referenced.
@@ -40508,7 +40507,16 @@ var ts;
                 var meaning = 788968 /* Type */;
                 if (isJSDocTypeReference(node)) {
                     type = getIntendedTypeFromJSDocTypeReference(node);
-                    meaning |= 111551 /* Value */;
+                    if (!type) {
+                        symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning, /*ignoreErrors*/ true);
+                        if (symbol === unknownSymbol) {
+                            symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning | 111551 /* Value */);
+                        }
+                        else {
+                            resolveTypeReferenceName(getTypeReferenceName(node), meaning); // Resolve again to mark errors, if any
+                        }
+                        type = getTypeReferenceType(node, symbol);
+                    }
                 }
                 if (!type) {
                     symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning);
@@ -41311,6 +41319,7 @@ var ts;
                         break;
                 }
             }
+            // tslint:disable no-unnecessary-type-assertion
             return links.resolvedType; // TODO: GH#18217
         }
         function createIndexedAccessType(objectType, indexType) {
@@ -55528,7 +55537,7 @@ var ts;
                 if (member.kind === 158 /* Constructor */) {
                     for (var _b = 0, _c = member.parameters; _b < _c.length; _b++) {
                         var param = _c[_b];
-                        if (ts.isParameterPropertyDeclaration(param) && !ts.isBindingPattern(param.name)) {
+                        if (ts.isParameterPropertyDeclaration(param, member) && !ts.isBindingPattern(param.name)) {
                             addName(instanceNames, param.name, param.name.escapedText, 3 /* GetOrSetAccessor */);
                         }
                     }
@@ -57100,7 +57109,7 @@ var ts;
                         var parameter = local.valueDeclaration && tryGetRootParameterDeclaration(local.valueDeclaration);
                         var name = local.valueDeclaration && ts.getNameOfDeclaration(local.valueDeclaration);
                         if (parameter && name) {
-                            if (!ts.isParameterPropertyDeclaration(parameter) && !ts.parameterIsThisKeyword(parameter) && !isIdentifierThatStartsWithUnderscore(name)) {
+                            if (!ts.isParameterPropertyDeclaration(parameter, parameter.parent) && !ts.parameterIsThisKeyword(parameter) && !isIdentifierThatStartsWithUnderscore(name)) {
                                 addDiagnostic(parameter, 1 /* Parameter */, ts.createDiagnosticForNode(name, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, ts.symbolName(local)));
                             }
                         }
@@ -58670,11 +58679,10 @@ var ts;
                     var constraint = ts.getEffectiveConstraintOfTypeParameter(source);
                     var sourceConstraint = constraint && getTypeFromTypeNode(constraint);
                     var targetConstraint = getConstraintOfTypeParameter(target);
-                    if (sourceConstraint) {
-                        // relax check if later interface augmentation has no constraint
-                        if (!targetConstraint || !isTypeIdenticalTo(sourceConstraint, targetConstraint)) {
-                            return false;
-                        }
+                    // relax check if later interface augmentation has no constraint, it's more broad and is OK to merge with
+                    // a more constrained interface (this could be generalized to a full heirarchy check, but that's maybe overkill)
+                    if (sourceConstraint && targetConstraint && !isTypeIdenticalTo(sourceConstraint, targetConstraint)) {
+                        return false;
                     }
                     // If the type parameter node has a default and it is not identical to the default
                     // for the type parameter at this position, we report an error.
@@ -62089,6 +62097,7 @@ var ts;
                 }
                 // Modifiers are never allowed on properties except for 'async' on a method declaration
                 if (prop.modifiers) {
+                    // tslint:disable no-unnecessary-type-assertion
                     for (var _b = 0, _c = prop.modifiers; _b < _c.length; _b++) { // TODO: GH#19955
                         var mod = _c[_b];
                         if (mod.kind !== 122 /* AsyncKeyword */ || prop.kind !== 157 /* MethodDeclaration */) {
@@ -70708,7 +70717,7 @@ var ts;
             var members = [];
             var constructor = ts.getFirstConstructorWithBody(node);
             var parametersWithPropertyAssignments = constructor &&
-                ts.filter(constructor.parameters, ts.isParameterPropertyDeclaration);
+                ts.filter(constructor.parameters, function (p) { return ts.isParameterPropertyDeclaration(p, constructor); });
             if (parametersWithPropertyAssignments) {
                 for (var _i = 0, parametersWithPropertyAssignments_1 = parametersWithPropertyAssignments; _i < parametersWithPropertyAssignments_1.length; _i++) {
                     var parameter = parametersWithPropertyAssignments_1[_i];
@@ -71555,7 +71564,7 @@ var ts;
         }
         function transformConstructorBody(body, constructor) {
             var parametersWithPropertyAssignments = constructor &&
-                ts.filter(constructor.parameters, ts.isParameterPropertyDeclaration);
+                ts.filter(constructor.parameters, function (p) { return ts.isParameterPropertyDeclaration(p, constructor); });
             if (!ts.some(parametersWithPropertyAssignments)) {
                 return ts.visitFunctionBody(body, visitor, context);
             }
@@ -72883,7 +72892,7 @@ var ts;
             if (constructor && constructor.body) {
                 var parameterPropertyDeclarationCount = 0;
                 for (var i = indexOfFirstStatement; i < constructor.body.statements.length; i++) {
-                    if (ts.isParameterPropertyDeclaration(ts.getOriginalNode(constructor.body.statements[i]))) {
+                    if (ts.isParameterPropertyDeclaration(ts.getOriginalNode(constructor.body.statements[i]), constructor)) {
                         parameterPropertyDeclarationCount++;
                     }
                     else {
@@ -84035,7 +84044,7 @@ var ts;
             return getReturnTypeVisibilityError;
         }
         else if (ts.isParameter(node)) {
-            if (ts.isParameterPropertyDeclaration(node) && ts.hasModifier(node.parent, 8 /* Private */)) {
+            if (ts.isParameterPropertyDeclaration(node, node.parent) && ts.hasModifier(node.parent, 8 /* Private */)) {
                 return getVariableDeclarationTypeVisibilityError;
             }
             return getParameterDeclarationTypeVisibilityError;
@@ -106223,7 +106232,7 @@ var ts;
             }
             Core.isSymbolReferencedInFile = isSymbolReferencedInFile;
             function eachSymbolReferenceInFile(definition, checker, sourceFile, cb) {
-                var symbol = ts.isParameterPropertyDeclaration(definition.parent)
+                var symbol = ts.isParameterPropertyDeclaration(definition.parent, definition.parent.parent)
                     ? ts.first(checker.getSymbolsOfParameterPropertyDeclaration(definition.parent, definition.text))
                     : checker.getSymbolAtLocation(definition);
                 if (!symbol)
@@ -106894,7 +106903,7 @@ var ts;
                 var res = fromRoot(symbol);
                 if (res)
                     return res;
-                if (symbol.valueDeclaration && ts.isParameterPropertyDeclaration(symbol.valueDeclaration)) {
+                if (symbol.valueDeclaration && ts.isParameterPropertyDeclaration(symbol.valueDeclaration, symbol.valueDeclaration.parent)) {
                     // For a parameter property, now try on the other symbol (property if this was a parameter, parameter if this was a property).
                     var paramProps = checker.getSymbolsOfParameterPropertyDeclaration(ts.cast(symbol.valueDeclaration, ts.isParameter), symbol.name);
                     ts.Debug.assert(paramProps.length === 2 && !!(paramProps[0].flags & 1 /* FunctionScopedVariable */) && !!(paramProps[1].flags & 4 /* Property */)); // is [parameter, property]
@@ -108214,7 +108223,7 @@ var ts;
                     // Parameter properties are children of the class, not the constructor.
                     for (var _i = 0, _a = ctr.parameters; _i < _a.length; _i++) {
                         var param = _a[_i];
-                        if (ts.isParameterPropertyDeclaration(param)) {
+                        if (ts.isParameterPropertyDeclaration(param, ctr)) {
                             addLeafNode(param);
                         }
                     }
@@ -123026,7 +123035,7 @@ var ts;
                 return ts.isIdentifier(name) || ts.isStringLiteral(name);
             }
             function isAcceptedDeclaration(node) {
-                return ts.isParameterPropertyDeclaration(node) || ts.isPropertyDeclaration(node) || ts.isPropertyAssignment(node);
+                return ts.isParameterPropertyDeclaration(node, node.parent) || ts.isPropertyDeclaration(node) || ts.isPropertyAssignment(node);
             }
             function createPropertyName(name, originalName) {
                 return ts.isIdentifier(originalName) ? ts.createIdentifier(name) : ts.createLiteral(name);
@@ -123105,7 +123114,7 @@ var ts;
                 }
             }
             function insertAccessor(changeTracker, file, accessor, declaration, container) {
-                ts.isParameterPropertyDeclaration(declaration)
+                ts.isParameterPropertyDeclaration(declaration, declaration.parent)
                     ? changeTracker.insertNodeAtClassStart(file, container, accessor)
                     : ts.isPropertyAssignment(declaration)
                         ? changeTracker.insertNodeAfterComma(file, declaration, accessor)
diff --git a/lib/tsserverlibrary.d.ts b/lib/tsserverlibrary.d.ts
index 768399664828e..5869f3641c858 100644
--- a/lib/tsserverlibrary.d.ts
+++ b/lib/tsserverlibrary.d.ts
@@ -3264,7 +3264,7 @@ declare namespace ts {
         parent: ConstructorDeclaration;
         name: Identifier;
     };
-    function isParameterPropertyDeclaration(node: Node): node is ParameterPropertyDeclaration;
+    function isParameterPropertyDeclaration(node: Node, parent: Node): node is ParameterPropertyDeclaration;
     function isEmptyBindingPattern(node: BindingName): node is BindingPattern;
     function isEmptyBindingElement(node: BindingElement): boolean;
     function walkUpBindingElementsAndPatterns(binding: BindingElement): VariableDeclaration | ParameterDeclaration;
diff --git a/lib/tsserverlibrary.js b/lib/tsserverlibrary.js
index c4825d9da0460..8df15d7214cbe 100644
--- a/lib/tsserverlibrary.js
+++ b/lib/tsserverlibrary.js
@@ -93,7 +93,7 @@ var ts;
     // If changing the text in this section, be sure to test `configureNightly` too.
     ts.versionMajorMinor = "3.6";
     /** The version of the TypeScript compiler release */
-    ts.version = ts.versionMajorMinor + ".3";
+    ts.version = ts.versionMajorMinor + ".4";
 })(ts || (ts = {}));
 (function (ts) {
     /* @internal */
@@ -9710,7 +9710,7 @@ var ts;
     }
     ts.isEnumConst = isEnumConst;
     function isDeclarationReadonly(declaration) {
-        return !!(ts.getCombinedModifierFlags(declaration) & 64 /* Readonly */ && !ts.isParameterPropertyDeclaration(declaration));
+        return !!(ts.getCombinedModifierFlags(declaration) & 64 /* Readonly */ && !ts.isParameterPropertyDeclaration(declaration, declaration.parent));
     }
     ts.isDeclarationReadonly = isDeclarationReadonly;
     function isVarConst(node) {
@@ -13419,8 +13419,8 @@ var ts;
         }
     }
     ts.getTypeParameterOwner = getTypeParameterOwner;
-    function isParameterPropertyDeclaration(node) {
-        return ts.hasModifier(node, 92 /* ParameterPropertyModifier */) && node.parent.kind === 158 /* Constructor */;
+    function isParameterPropertyDeclaration(node, parent) {
+        return ts.hasModifier(node, 92 /* ParameterPropertyModifier */) && parent.kind === 158 /* Constructor */;
     }
     ts.isParameterPropertyDeclaration = isParameterPropertyDeclaration;
     function isEmptyBindingPattern(node) {
@@ -30761,7 +30761,7 @@ var ts;
             }
             // If this is a property-parameter, then also declare the property symbol into the
             // containing class.
-            if (ts.isParameterPropertyDeclaration(node)) {
+            if (ts.isParameterPropertyDeclaration(node, node.parent)) {
                 var classDeclaration = node.parent.parent;
                 declareSymbol(classDeclaration.symbol.members, classDeclaration.symbol, node, 4 /* Property */ | (node.questionToken ? 16777216 /* Optional */ : 0 /* None */), 0 /* PropertyExcludes */);
             }
@@ -40119,8 +40119,7 @@ var ts;
             return undefined;
         }
         function getConstraintDeclaration(type) {
-            var decl = type.symbol && ts.getDeclarationOfKind(type.symbol, 151 /* TypeParameter */);
-            return decl && ts.getEffectiveConstraintOfTypeParameter(decl);
+            return ts.mapDefined(ts.filter(type.symbol && type.symbol.declarations, ts.isTypeParameterDeclaration), ts.getEffectiveConstraintOfTypeParameter)[0];
         }
         function getInferredTypeParameterConstraint(typeParameter) {
             var inferences;
@@ -40328,11 +40327,11 @@ var ts;
             }
             return undefined;
         }
-        function resolveTypeReferenceName(typeReferenceName, meaning) {
+        function resolveTypeReferenceName(typeReferenceName, meaning, ignoreErrors) {
             if (!typeReferenceName) {
                 return unknownSymbol;
             }
-            return resolveEntityName(typeReferenceName, meaning) || unknownSymbol;
+            return resolveEntityName(typeReferenceName, meaning, ignoreErrors) || unknownSymbol;
         }
         function getTypeReferenceType(node, symbol) {
             var typeArguments = typeArgumentsFromTypeReferenceNode(node); // Do unconditionally so we mark type arguments as referenced.
@@ -40507,7 +40506,16 @@ var ts;
                 var meaning = 788968 /* Type */;
                 if (isJSDocTypeReference(node)) {
                     type = getIntendedTypeFromJSDocTypeReference(node);
-                    meaning |= 111551 /* Value */;
+                    if (!type) {
+                        symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning, /*ignoreErrors*/ true);
+                        if (symbol === unknownSymbol) {
+                            symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning | 111551 /* Value */);
+                        }
+                        else {
+                            resolveTypeReferenceName(getTypeReferenceName(node), meaning); // Resolve again to mark errors, if any
+                        }
+                        type = getTypeReferenceType(node, symbol);
+                    }
                 }
                 if (!type) {
                     symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning);
@@ -41310,6 +41318,7 @@ var ts;
                         break;
                 }
             }
+            // tslint:disable no-unnecessary-type-assertion
             return links.resolvedType; // TODO: GH#18217
         }
         function createIndexedAccessType(objectType, indexType) {
@@ -55527,7 +55536,7 @@ var ts;
                 if (member.kind === 158 /* Constructor */) {
                     for (var _b = 0, _c = member.parameters; _b < _c.length; _b++) {
                         var param = _c[_b];
-                        if (ts.isParameterPropertyDeclaration(param) && !ts.isBindingPattern(param.name)) {
+                        if (ts.isParameterPropertyDeclaration(param, member) && !ts.isBindingPattern(param.name)) {
                             addName(instanceNames, param.name, param.name.escapedText, 3 /* GetOrSetAccessor */);
                         }
                     }
@@ -57099,7 +57108,7 @@ var ts;
                         var parameter = local.valueDeclaration && tryGetRootParameterDeclaration(local.valueDeclaration);
                         var name = local.valueDeclaration && ts.getNameOfDeclaration(local.valueDeclaration);
                         if (parameter && name) {
-                            if (!ts.isParameterPropertyDeclaration(parameter) && !ts.parameterIsThisKeyword(parameter) && !isIdentifierThatStartsWithUnderscore(name)) {
+                            if (!ts.isParameterPropertyDeclaration(parameter, parameter.parent) && !ts.parameterIsThisKeyword(parameter) && !isIdentifierThatStartsWithUnderscore(name)) {
                                 addDiagnostic(parameter, 1 /* Parameter */, ts.createDiagnosticForNode(name, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, ts.symbolName(local)));
                             }
                         }
@@ -58669,11 +58678,10 @@ var ts;
                     var constraint = ts.getEffectiveConstraintOfTypeParameter(source);
                     var sourceConstraint = constraint && getTypeFromTypeNode(constraint);
                     var targetConstraint = getConstraintOfTypeParameter(target);
-                    if (sourceConstraint) {
-                        // relax check if later interface augmentation has no constraint
-                        if (!targetConstraint || !isTypeIdenticalTo(sourceConstraint, targetConstraint)) {
-                            return false;
-                        }
+                    // relax check if later interface augmentation has no constraint, it's more broad and is OK to merge with
+                    // a more constrained interface (this could be generalized to a full heirarchy check, but that's maybe overkill)
+                    if (sourceConstraint && targetConstraint && !isTypeIdenticalTo(sourceConstraint, targetConstraint)) {
+                        return false;
                     }
                     // If the type parameter node has a default and it is not identical to the default
                     // for the type parameter at this position, we report an error.
@@ -62088,6 +62096,7 @@ var ts;
                 }
                 // Modifiers are never allowed on properties except for 'async' on a method declaration
                 if (prop.modifiers) {
+                    // tslint:disable no-unnecessary-type-assertion
                     for (var _b = 0, _c = prop.modifiers; _b < _c.length; _b++) { // TODO: GH#19955
                         var mod = _c[_b];
                         if (mod.kind !== 122 /* AsyncKeyword */ || prop.kind !== 157 /* MethodDeclaration */) {
@@ -70707,7 +70716,7 @@ var ts;
             var members = [];
             var constructor = ts.getFirstConstructorWithBody(node);
             var parametersWithPropertyAssignments = constructor &&
-                ts.filter(constructor.parameters, ts.isParameterPropertyDeclaration);
+                ts.filter(constructor.parameters, function (p) { return ts.isParameterPropertyDeclaration(p, constructor); });
             if (parametersWithPropertyAssignments) {
                 for (var _i = 0, parametersWithPropertyAssignments_1 = parametersWithPropertyAssignments; _i < parametersWithPropertyAssignments_1.length; _i++) {
                     var parameter = parametersWithPropertyAssignments_1[_i];
@@ -71554,7 +71563,7 @@ var ts;
         }
         function transformConstructorBody(body, constructor) {
             var parametersWithPropertyAssignments = constructor &&
-                ts.filter(constructor.parameters, ts.isParameterPropertyDeclaration);
+                ts.filter(constructor.parameters, function (p) { return ts.isParameterPropertyDeclaration(p, constructor); });
             if (!ts.some(parametersWithPropertyAssignments)) {
                 return ts.visitFunctionBody(body, visitor, context);
             }
@@ -72882,7 +72891,7 @@ var ts;
             if (constructor && constructor.body) {
                 var parameterPropertyDeclarationCount = 0;
                 for (var i = indexOfFirstStatement; i < constructor.body.statements.length; i++) {
-                    if (ts.isParameterPropertyDeclaration(ts.getOriginalNode(constructor.body.statements[i]))) {
+                    if (ts.isParameterPropertyDeclaration(ts.getOriginalNode(constructor.body.statements[i]), constructor)) {
                         parameterPropertyDeclarationCount++;
                     }
                     else {
@@ -84034,7 +84043,7 @@ var ts;
             return getReturnTypeVisibilityError;
         }
         else if (ts.isParameter(node)) {
-            if (ts.isParameterPropertyDeclaration(node) && ts.hasModifier(node.parent, 8 /* Private */)) {
+            if (ts.isParameterPropertyDeclaration(node, node.parent) && ts.hasModifier(node.parent, 8 /* Private */)) {
                 return getVariableDeclarationTypeVisibilityError;
             }
             return getParameterDeclarationTypeVisibilityError;
@@ -106586,7 +106595,7 @@ var ts;
             }
             Core.isSymbolReferencedInFile = isSymbolReferencedInFile;
             function eachSymbolReferenceInFile(definition, checker, sourceFile, cb) {
-                var symbol = ts.isParameterPropertyDeclaration(definition.parent)
+                var symbol = ts.isParameterPropertyDeclaration(definition.parent, definition.parent.parent)
                     ? ts.first(checker.getSymbolsOfParameterPropertyDeclaration(definition.parent, definition.text))
                     : checker.getSymbolAtLocation(definition);
                 if (!symbol)
@@ -107257,7 +107266,7 @@ var ts;
                 var res = fromRoot(symbol);
                 if (res)
                     return res;
-                if (symbol.valueDeclaration && ts.isParameterPropertyDeclaration(symbol.valueDeclaration)) {
+                if (symbol.valueDeclaration && ts.isParameterPropertyDeclaration(symbol.valueDeclaration, symbol.valueDeclaration.parent)) {
                     // For a parameter property, now try on the other symbol (property if this was a parameter, parameter if this was a property).
                     var paramProps = checker.getSymbolsOfParameterPropertyDeclaration(ts.cast(symbol.valueDeclaration, ts.isParameter), symbol.name);
                     ts.Debug.assert(paramProps.length === 2 && !!(paramProps[0].flags & 1 /* FunctionScopedVariable */) && !!(paramProps[1].flags & 4 /* Property */)); // is [parameter, property]
@@ -108577,7 +108586,7 @@ var ts;
                     // Parameter properties are children of the class, not the constructor.
                     for (var _i = 0, _a = ctr.parameters; _i < _a.length; _i++) {
                         var param = _a[_i];
-                        if (ts.isParameterPropertyDeclaration(param)) {
+                        if (ts.isParameterPropertyDeclaration(param, ctr)) {
                             addLeafNode(param);
                         }
                     }
@@ -123389,7 +123398,7 @@ var ts;
                 return ts.isIdentifier(name) || ts.isStringLiteral(name);
             }
             function isAcceptedDeclaration(node) {
-                return ts.isParameterPropertyDeclaration(node) || ts.isPropertyDeclaration(node) || ts.isPropertyAssignment(node);
+                return ts.isParameterPropertyDeclaration(node, node.parent) || ts.isPropertyDeclaration(node) || ts.isPropertyAssignment(node);
             }
             function createPropertyName(name, originalName) {
                 return ts.isIdentifier(originalName) ? ts.createIdentifier(name) : ts.createLiteral(name);
@@ -123468,7 +123477,7 @@ var ts;
                 }
             }
             function insertAccessor(changeTracker, file, accessor, declaration, container) {
-                ts.isParameterPropertyDeclaration(declaration)
+                ts.isParameterPropertyDeclaration(declaration, declaration.parent)
                     ? changeTracker.insertNodeAtClassStart(file, container, accessor)
                     : ts.isPropertyAssignment(declaration)
                         ? changeTracker.insertNodeAfterComma(file, declaration, accessor)
diff --git a/lib/typescript.d.ts b/lib/typescript.d.ts
index 811f3b3507c53..48bfe8b34724f 100644
--- a/lib/typescript.d.ts
+++ b/lib/typescript.d.ts
@@ -3264,7 +3264,7 @@ declare namespace ts {
         parent: ConstructorDeclaration;
         name: Identifier;
     };
-    function isParameterPropertyDeclaration(node: Node): node is ParameterPropertyDeclaration;
+    function isParameterPropertyDeclaration(node: Node, parent: Node): node is ParameterPropertyDeclaration;
     function isEmptyBindingPattern(node: BindingName): node is BindingPattern;
     function isEmptyBindingElement(node: BindingElement): boolean;
     function walkUpBindingElementsAndPatterns(binding: BindingElement): VariableDeclaration | ParameterDeclaration;
diff --git a/lib/typescript.js b/lib/typescript.js
index d078259e4ed81..fd7aaa5b59f0a 100644
--- a/lib/typescript.js
+++ b/lib/typescript.js
@@ -82,7 +82,7 @@ var ts;
     // If changing the text in this section, be sure to test `configureNightly` too.
     ts.versionMajorMinor = "3.6";
     /** The version of the TypeScript compiler release */
-    ts.version = ts.versionMajorMinor + ".3";
+    ts.version = ts.versionMajorMinor + ".4";
 })(ts || (ts = {}));
 (function (ts) {
     /* @internal */
@@ -9699,7 +9699,7 @@ var ts;
     }
     ts.isEnumConst = isEnumConst;
     function isDeclarationReadonly(declaration) {
-        return !!(ts.getCombinedModifierFlags(declaration) & 64 /* Readonly */ && !ts.isParameterPropertyDeclaration(declaration));
+        return !!(ts.getCombinedModifierFlags(declaration) & 64 /* Readonly */ && !ts.isParameterPropertyDeclaration(declaration, declaration.parent));
     }
     ts.isDeclarationReadonly = isDeclarationReadonly;
     function isVarConst(node) {
@@ -13408,8 +13408,8 @@ var ts;
         }
     }
     ts.getTypeParameterOwner = getTypeParameterOwner;
-    function isParameterPropertyDeclaration(node) {
-        return ts.hasModifier(node, 92 /* ParameterPropertyModifier */) && node.parent.kind === 158 /* Constructor */;
+    function isParameterPropertyDeclaration(node, parent) {
+        return ts.hasModifier(node, 92 /* ParameterPropertyModifier */) && parent.kind === 158 /* Constructor */;
     }
     ts.isParameterPropertyDeclaration = isParameterPropertyDeclaration;
     function isEmptyBindingPattern(node) {
@@ -30750,7 +30750,7 @@ var ts;
             }
             // If this is a property-parameter, then also declare the property symbol into the
             // containing class.
-            if (ts.isParameterPropertyDeclaration(node)) {
+            if (ts.isParameterPropertyDeclaration(node, node.parent)) {
                 var classDeclaration = node.parent.parent;
                 declareSymbol(classDeclaration.symbol.members, classDeclaration.symbol, node, 4 /* Property */ | (node.questionToken ? 16777216 /* Optional */ : 0 /* None */), 0 /* PropertyExcludes */);
             }
@@ -40108,8 +40108,7 @@ var ts;
             return undefined;
         }
         function getConstraintDeclaration(type) {
-            var decl = type.symbol && ts.getDeclarationOfKind(type.symbol, 151 /* TypeParameter */);
-            return decl && ts.getEffectiveConstraintOfTypeParameter(decl);
+            return ts.mapDefined(ts.filter(type.symbol && type.symbol.declarations, ts.isTypeParameterDeclaration), ts.getEffectiveConstraintOfTypeParameter)[0];
         }
         function getInferredTypeParameterConstraint(typeParameter) {
             var inferences;
@@ -40317,11 +40316,11 @@ var ts;
             }
             return undefined;
         }
-        function resolveTypeReferenceName(typeReferenceName, meaning) {
+        function resolveTypeReferenceName(typeReferenceName, meaning, ignoreErrors) {
             if (!typeReferenceName) {
                 return unknownSymbol;
             }
-            return resolveEntityName(typeReferenceName, meaning) || unknownSymbol;
+            return resolveEntityName(typeReferenceName, meaning, ignoreErrors) || unknownSymbol;
         }
         function getTypeReferenceType(node, symbol) {
             var typeArguments = typeArgumentsFromTypeReferenceNode(node); // Do unconditionally so we mark type arguments as referenced.
@@ -40496,7 +40495,16 @@ var ts;
                 var meaning = 788968 /* Type */;
                 if (isJSDocTypeReference(node)) {
                     type = getIntendedTypeFromJSDocTypeReference(node);
-                    meaning |= 111551 /* Value */;
+                    if (!type) {
+                        symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning, /*ignoreErrors*/ true);
+                        if (symbol === unknownSymbol) {
+                            symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning | 111551 /* Value */);
+                        }
+                        else {
+                            resolveTypeReferenceName(getTypeReferenceName(node), meaning); // Resolve again to mark errors, if any
+                        }
+                        type = getTypeReferenceType(node, symbol);
+                    }
                 }
                 if (!type) {
                     symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning);
@@ -41299,6 +41307,7 @@ var ts;
                         break;
                 }
             }
+            // tslint:disable no-unnecessary-type-assertion
             return links.resolvedType; // TODO: GH#18217
         }
         function createIndexedAccessType(objectType, indexType) {
@@ -55516,7 +55525,7 @@ var ts;
                 if (member.kind === 158 /* Constructor */) {
                     for (var _b = 0, _c = member.parameters; _b < _c.length; _b++) {
                         var param = _c[_b];
-                        if (ts.isParameterPropertyDeclaration(param) && !ts.isBindingPattern(param.name)) {
+                        if (ts.isParameterPropertyDeclaration(param, member) && !ts.isBindingPattern(param.name)) {
                             addName(instanceNames, param.name, param.name.escapedText, 3 /* GetOrSetAccessor */);
                         }
                     }
@@ -57088,7 +57097,7 @@ var ts;
                         var parameter = local.valueDeclaration && tryGetRootParameterDeclaration(local.valueDeclaration);
                         var name = local.valueDeclaration && ts.getNameOfDeclaration(local.valueDeclaration);
                         if (parameter && name) {
-                            if (!ts.isParameterPropertyDeclaration(parameter) && !ts.parameterIsThisKeyword(parameter) && !isIdentifierThatStartsWithUnderscore(name)) {
+                            if (!ts.isParameterPropertyDeclaration(parameter, parameter.parent) && !ts.parameterIsThisKeyword(parameter) && !isIdentifierThatStartsWithUnderscore(name)) {
                                 addDiagnostic(parameter, 1 /* Parameter */, ts.createDiagnosticForNode(name, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, ts.symbolName(local)));
                             }
                         }
@@ -58658,11 +58667,10 @@ var ts;
                     var constraint = ts.getEffectiveConstraintOfTypeParameter(source);
                     var sourceConstraint = constraint && getTypeFromTypeNode(constraint);
                     var targetConstraint = getConstraintOfTypeParameter(target);
-                    if (sourceConstraint) {
-                        // relax check if later interface augmentation has no constraint
-                        if (!targetConstraint || !isTypeIdenticalTo(sourceConstraint, targetConstraint)) {
-                            return false;
-                        }
+                    // relax check if later interface augmentation has no constraint, it's more broad and is OK to merge with
+                    // a more constrained interface (this could be generalized to a full heirarchy check, but that's maybe overkill)
+                    if (sourceConstraint && targetConstraint && !isTypeIdenticalTo(sourceConstraint, targetConstraint)) {
+                        return false;
                     }
                     // If the type parameter node has a default and it is not identical to the default
                     // for the type parameter at this position, we report an error.
@@ -62077,6 +62085,7 @@ var ts;
                 }
                 // Modifiers are never allowed on properties except for 'async' on a method declaration
                 if (prop.modifiers) {
+                    // tslint:disable no-unnecessary-type-assertion
                     for (var _b = 0, _c = prop.modifiers; _b < _c.length; _b++) { // TODO: GH#19955
                         var mod = _c[_b];
                         if (mod.kind !== 122 /* AsyncKeyword */ || prop.kind !== 157 /* MethodDeclaration */) {
@@ -70696,7 +70705,7 @@ var ts;
             var members = [];
             var constructor = ts.getFirstConstructorWithBody(node);
             var parametersWithPropertyAssignments = constructor &&
-                ts.filter(constructor.parameters, ts.isParameterPropertyDeclaration);
+                ts.filter(constructor.parameters, function (p) { return ts.isParameterPropertyDeclaration(p, constructor); });
             if (parametersWithPropertyAssignments) {
                 for (var _i = 0, parametersWithPropertyAssignments_1 = parametersWithPropertyAssignments; _i < parametersWithPropertyAssignments_1.length; _i++) {
                     var parameter = parametersWithPropertyAssignments_1[_i];
@@ -71543,7 +71552,7 @@ var ts;
         }
         function transformConstructorBody(body, constructor) {
             var parametersWithPropertyAssignments = constructor &&
-                ts.filter(constructor.parameters, ts.isParameterPropertyDeclaration);
+                ts.filter(constructor.parameters, function (p) { return ts.isParameterPropertyDeclaration(p, constructor); });
             if (!ts.some(parametersWithPropertyAssignments)) {
                 return ts.visitFunctionBody(body, visitor, context);
             }
@@ -72871,7 +72880,7 @@ var ts;
             if (constructor && constructor.body) {
                 var parameterPropertyDeclarationCount = 0;
                 for (var i = indexOfFirstStatement; i < constructor.body.statements.length; i++) {
-                    if (ts.isParameterPropertyDeclaration(ts.getOriginalNode(constructor.body.statements[i]))) {
+                    if (ts.isParameterPropertyDeclaration(ts.getOriginalNode(constructor.body.statements[i]), constructor)) {
                         parameterPropertyDeclarationCount++;
                     }
                     else {
@@ -84023,7 +84032,7 @@ var ts;
             return getReturnTypeVisibilityError;
         }
         else if (ts.isParameter(node)) {
-            if (ts.isParameterPropertyDeclaration(node) && ts.hasModifier(node.parent, 8 /* Private */)) {
+            if (ts.isParameterPropertyDeclaration(node, node.parent) && ts.hasModifier(node.parent, 8 /* Private */)) {
                 return getVariableDeclarationTypeVisibilityError;
             }
             return getParameterDeclarationTypeVisibilityError;
@@ -106575,7 +106584,7 @@ var ts;
             }
             Core.isSymbolReferencedInFile = isSymbolReferencedInFile;
             function eachSymbolReferenceInFile(definition, checker, sourceFile, cb) {
-                var symbol = ts.isParameterPropertyDeclaration(definition.parent)
+                var symbol = ts.isParameterPropertyDeclaration(definition.parent, definition.parent.parent)
                     ? ts.first(checker.getSymbolsOfParameterPropertyDeclaration(definition.parent, definition.text))
                     : checker.getSymbolAtLocation(definition);
                 if (!symbol)
@@ -107246,7 +107255,7 @@ var ts;
                 var res = fromRoot(symbol);
                 if (res)
                     return res;
-                if (symbol.valueDeclaration && ts.isParameterPropertyDeclaration(symbol.valueDeclaration)) {
+                if (symbol.valueDeclaration && ts.isParameterPropertyDeclaration(symbol.valueDeclaration, symbol.valueDeclaration.parent)) {
                     // For a parameter property, now try on the other symbol (property if this was a parameter, parameter if this was a property).
                     var paramProps = checker.getSymbolsOfParameterPropertyDeclaration(ts.cast(symbol.valueDeclaration, ts.isParameter), symbol.name);
                     ts.Debug.assert(paramProps.length === 2 && !!(paramProps[0].flags & 1 /* FunctionScopedVariable */) && !!(paramProps[1].flags & 4 /* Property */)); // is [parameter, property]
@@ -108566,7 +108575,7 @@ var ts;
                     // Parameter properties are children of the class, not the constructor.
                     for (var _i = 0, _a = ctr.parameters; _i < _a.length; _i++) {
                         var param = _a[_i];
-                        if (ts.isParameterPropertyDeclaration(param)) {
+                        if (ts.isParameterPropertyDeclaration(param, ctr)) {
                             addLeafNode(param);
                         }
                     }
@@ -123378,7 +123387,7 @@ var ts;
                 return ts.isIdentifier(name) || ts.isStringLiteral(name);
             }
             function isAcceptedDeclaration(node) {
-                return ts.isParameterPropertyDeclaration(node) || ts.isPropertyDeclaration(node) || ts.isPropertyAssignment(node);
+                return ts.isParameterPropertyDeclaration(node, node.parent) || ts.isPropertyDeclaration(node) || ts.isPropertyAssignment(node);
             }
             function createPropertyName(name, originalName) {
                 return ts.isIdentifier(originalName) ? ts.createIdentifier(name) : ts.createLiteral(name);
@@ -123457,7 +123466,7 @@ var ts;
                 }
             }
             function insertAccessor(changeTracker, file, accessor, declaration, container) {
-                ts.isParameterPropertyDeclaration(declaration)
+                ts.isParameterPropertyDeclaration(declaration, declaration.parent)
                     ? changeTracker.insertNodeAtClassStart(file, container, accessor)
                     : ts.isPropertyAssignment(declaration)
                         ? changeTracker.insertNodeAfterComma(file, declaration, accessor)
diff --git a/lib/typescriptServices.d.ts b/lib/typescriptServices.d.ts
index 828a2d4732644..c98678ae30232 100644
--- a/lib/typescriptServices.d.ts
+++ b/lib/typescriptServices.d.ts
@@ -3264,7 +3264,7 @@ declare namespace ts {
         parent: ConstructorDeclaration;
         name: Identifier;
     };
-    function isParameterPropertyDeclaration(node: Node): node is ParameterPropertyDeclaration;
+    function isParameterPropertyDeclaration(node: Node, parent: Node): node is ParameterPropertyDeclaration;
     function isEmptyBindingPattern(node: BindingName): node is BindingPattern;
     function isEmptyBindingElement(node: BindingElement): boolean;
     function walkUpBindingElementsAndPatterns(binding: BindingElement): VariableDeclaration | ParameterDeclaration;
diff --git a/lib/typescriptServices.js b/lib/typescriptServices.js
index 467b2716b4326..d41325d6b5b56 100644
--- a/lib/typescriptServices.js
+++ b/lib/typescriptServices.js
@@ -82,7 +82,7 @@ var ts;
     // If changing the text in this section, be sure to test `configureNightly` too.
     ts.versionMajorMinor = "3.6";
     /** The version of the TypeScript compiler release */
-    ts.version = ts.versionMajorMinor + ".3";
+    ts.version = ts.versionMajorMinor + ".4";
 })(ts || (ts = {}));
 (function (ts) {
     /* @internal */
@@ -9699,7 +9699,7 @@ var ts;
     }
     ts.isEnumConst = isEnumConst;
     function isDeclarationReadonly(declaration) {
-        return !!(ts.getCombinedModifierFlags(declaration) & 64 /* Readonly */ && !ts.isParameterPropertyDeclaration(declaration));
+        return !!(ts.getCombinedModifierFlags(declaration) & 64 /* Readonly */ && !ts.isParameterPropertyDeclaration(declaration, declaration.parent));
     }
     ts.isDeclarationReadonly = isDeclarationReadonly;
     function isVarConst(node) {
@@ -13408,8 +13408,8 @@ var ts;
         }
     }
     ts.getTypeParameterOwner = getTypeParameterOwner;
-    function isParameterPropertyDeclaration(node) {
-        return ts.hasModifier(node, 92 /* ParameterPropertyModifier */) && node.parent.kind === 158 /* Constructor */;
+    function isParameterPropertyDeclaration(node, parent) {
+        return ts.hasModifier(node, 92 /* ParameterPropertyModifier */) && parent.kind === 158 /* Constructor */;
     }
     ts.isParameterPropertyDeclaration = isParameterPropertyDeclaration;
     function isEmptyBindingPattern(node) {
@@ -30750,7 +30750,7 @@ var ts;
             }
             // If this is a property-parameter, then also declare the property symbol into the
             // containing class.
-            if (ts.isParameterPropertyDeclaration(node)) {
+            if (ts.isParameterPropertyDeclaration(node, node.parent)) {
                 var classDeclaration = node.parent.parent;
                 declareSymbol(classDeclaration.symbol.members, classDeclaration.symbol, node, 4 /* Property */ | (node.questionToken ? 16777216 /* Optional */ : 0 /* None */), 0 /* PropertyExcludes */);
             }
@@ -40108,8 +40108,7 @@ var ts;
             return undefined;
         }
         function getConstraintDeclaration(type) {
-            var decl = type.symbol && ts.getDeclarationOfKind(type.symbol, 151 /* TypeParameter */);
-            return decl && ts.getEffectiveConstraintOfTypeParameter(decl);
+            return ts.mapDefined(ts.filter(type.symbol && type.symbol.declarations, ts.isTypeParameterDeclaration), ts.getEffectiveConstraintOfTypeParameter)[0];
         }
         function getInferredTypeParameterConstraint(typeParameter) {
             var inferences;
@@ -40317,11 +40316,11 @@ var ts;
             }
             return undefined;
         }
-        function resolveTypeReferenceName(typeReferenceName, meaning) {
+        function resolveTypeReferenceName(typeReferenceName, meaning, ignoreErrors) {
             if (!typeReferenceName) {
                 return unknownSymbol;
             }
-            return resolveEntityName(typeReferenceName, meaning) || unknownSymbol;
+            return resolveEntityName(typeReferenceName, meaning, ignoreErrors) || unknownSymbol;
         }
         function getTypeReferenceType(node, symbol) {
             var typeArguments = typeArgumentsFromTypeReferenceNode(node); // Do unconditionally so we mark type arguments as referenced.
@@ -40496,7 +40495,16 @@ var ts;
                 var meaning = 788968 /* Type */;
                 if (isJSDocTypeReference(node)) {
                     type = getIntendedTypeFromJSDocTypeReference(node);
-                    meaning |= 111551 /* Value */;
+                    if (!type) {
+                        symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning, /*ignoreErrors*/ true);
+                        if (symbol === unknownSymbol) {
+                            symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning | 111551 /* Value */);
+                        }
+                        else {
+                            resolveTypeReferenceName(getTypeReferenceName(node), meaning); // Resolve again to mark errors, if any
+                        }
+                        type = getTypeReferenceType(node, symbol);
+                    }
                 }
                 if (!type) {
                     symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning);
@@ -41299,6 +41307,7 @@ var ts;
                         break;
                 }
             }
+            // tslint:disable no-unnecessary-type-assertion
             return links.resolvedType; // TODO: GH#18217
         }
         function createIndexedAccessType(objectType, indexType) {
@@ -55516,7 +55525,7 @@ var ts;
                 if (member.kind === 158 /* Constructor */) {
                     for (var _b = 0, _c = member.parameters; _b < _c.length; _b++) {
                         var param = _c[_b];
-                        if (ts.isParameterPropertyDeclaration(param) && !ts.isBindingPattern(param.name)) {
+                        if (ts.isParameterPropertyDeclaration(param, member) && !ts.isBindingPattern(param.name)) {
                             addName(instanceNames, param.name, param.name.escapedText, 3 /* GetOrSetAccessor */);
                         }
                     }
@@ -57088,7 +57097,7 @@ var ts;
                         var parameter = local.valueDeclaration && tryGetRootParameterDeclaration(local.valueDeclaration);
                         var name = local.valueDeclaration && ts.getNameOfDeclaration(local.valueDeclaration);
                         if (parameter && name) {
-                            if (!ts.isParameterPropertyDeclaration(parameter) && !ts.parameterIsThisKeyword(parameter) && !isIdentifierThatStartsWithUnderscore(name)) {
+                            if (!ts.isParameterPropertyDeclaration(parameter, parameter.parent) && !ts.parameterIsThisKeyword(parameter) && !isIdentifierThatStartsWithUnderscore(name)) {
                                 addDiagnostic(parameter, 1 /* Parameter */, ts.createDiagnosticForNode(name, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, ts.symbolName(local)));
                             }
                         }
@@ -58658,11 +58667,10 @@ var ts;
                     var constraint = ts.getEffectiveConstraintOfTypeParameter(source);
                     var sourceConstraint = constraint && getTypeFromTypeNode(constraint);
                     var targetConstraint = getConstraintOfTypeParameter(target);
-                    if (sourceConstraint) {
-                        // relax check if later interface augmentation has no constraint
-                        if (!targetConstraint || !isTypeIdenticalTo(sourceConstraint, targetConstraint)) {
-                            return false;
-                        }
+                    // relax check if later interface augmentation has no constraint, it's more broad and is OK to merge with
+                    // a more constrained interface (this could be generalized to a full heirarchy check, but that's maybe overkill)
+                    if (sourceConstraint && targetConstraint && !isTypeIdenticalTo(sourceConstraint, targetConstraint)) {
+                        return false;
                     }
                     // If the type parameter node has a default and it is not identical to the default
                     // for the type parameter at this position, we report an error.
@@ -62077,6 +62085,7 @@ var ts;
                 }
                 // Modifiers are never allowed on properties except for 'async' on a method declaration
                 if (prop.modifiers) {
+                    // tslint:disable no-unnecessary-type-assertion
                     for (var _b = 0, _c = prop.modifiers; _b < _c.length; _b++) { // TODO: GH#19955
                         var mod = _c[_b];
                         if (mod.kind !== 122 /* AsyncKeyword */ || prop.kind !== 157 /* MethodDeclaration */) {
@@ -70696,7 +70705,7 @@ var ts;
             var members = [];
             var constructor = ts.getFirstConstructorWithBody(node);
             var parametersWithPropertyAssignments = constructor &&
-                ts.filter(constructor.parameters, ts.isParameterPropertyDeclaration);
+                ts.filter(constructor.parameters, function (p) { return ts.isParameterPropertyDeclaration(p, constructor); });
             if (parametersWithPropertyAssignments) {
                 for (var _i = 0, parametersWithPropertyAssignments_1 = parametersWithPropertyAssignments; _i < parametersWithPropertyAssignments_1.length; _i++) {
                     var parameter = parametersWithPropertyAssignments_1[_i];
@@ -71543,7 +71552,7 @@ var ts;
         }
         function transformConstructorBody(body, constructor) {
             var parametersWithPropertyAssignments = constructor &&
-                ts.filter(constructor.parameters, ts.isParameterPropertyDeclaration);
+                ts.filter(constructor.parameters, function (p) { return ts.isParameterPropertyDeclaration(p, constructor); });
             if (!ts.some(parametersWithPropertyAssignments)) {
                 return ts.visitFunctionBody(body, visitor, context);
             }
@@ -72871,7 +72880,7 @@ var ts;
             if (constructor && constructor.body) {
                 var parameterPropertyDeclarationCount = 0;
                 for (var i = indexOfFirstStatement; i < constructor.body.statements.length; i++) {
-                    if (ts.isParameterPropertyDeclaration(ts.getOriginalNode(constructor.body.statements[i]))) {
+                    if (ts.isParameterPropertyDeclaration(ts.getOriginalNode(constructor.body.statements[i]), constructor)) {
                         parameterPropertyDeclarationCount++;
                     }
                     else {
@@ -84023,7 +84032,7 @@ var ts;
             return getReturnTypeVisibilityError;
         }
         else if (ts.isParameter(node)) {
-            if (ts.isParameterPropertyDeclaration(node) && ts.hasModifier(node.parent, 8 /* Private */)) {
+            if (ts.isParameterPropertyDeclaration(node, node.parent) && ts.hasModifier(node.parent, 8 /* Private */)) {
                 return getVariableDeclarationTypeVisibilityError;
             }
             return getParameterDeclarationTypeVisibilityError;
@@ -106575,7 +106584,7 @@ var ts;
             }
             Core.isSymbolReferencedInFile = isSymbolReferencedInFile;
             function eachSymbolReferenceInFile(definition, checker, sourceFile, cb) {
-                var symbol = ts.isParameterPropertyDeclaration(definition.parent)
+                var symbol = ts.isParameterPropertyDeclaration(definition.parent, definition.parent.parent)
                     ? ts.first(checker.getSymbolsOfParameterPropertyDeclaration(definition.parent, definition.text))
                     : checker.getSymbolAtLocation(definition);
                 if (!symbol)
@@ -107246,7 +107255,7 @@ var ts;
                 var res = fromRoot(symbol);
                 if (res)
                     return res;
-                if (symbol.valueDeclaration && ts.isParameterPropertyDeclaration(symbol.valueDeclaration)) {
+                if (symbol.valueDeclaration && ts.isParameterPropertyDeclaration(symbol.valueDeclaration, symbol.valueDeclaration.parent)) {
                     // For a parameter property, now try on the other symbol (property if this was a parameter, parameter if this was a property).
                     var paramProps = checker.getSymbolsOfParameterPropertyDeclaration(ts.cast(symbol.valueDeclaration, ts.isParameter), symbol.name);
                     ts.Debug.assert(paramProps.length === 2 && !!(paramProps[0].flags & 1 /* FunctionScopedVariable */) && !!(paramProps[1].flags & 4 /* Property */)); // is [parameter, property]
@@ -108566,7 +108575,7 @@ var ts;
                     // Parameter properties are children of the class, not the constructor.
                     for (var _i = 0, _a = ctr.parameters; _i < _a.length; _i++) {
                         var param = _a[_i];
-                        if (ts.isParameterPropertyDeclaration(param)) {
+                        if (ts.isParameterPropertyDeclaration(param, ctr)) {
                             addLeafNode(param);
                         }
                     }
@@ -123378,7 +123387,7 @@ var ts;
                 return ts.isIdentifier(name) || ts.isStringLiteral(name);
             }
             function isAcceptedDeclaration(node) {
-                return ts.isParameterPropertyDeclaration(node) || ts.isPropertyDeclaration(node) || ts.isPropertyAssignment(node);
+                return ts.isParameterPropertyDeclaration(node, node.parent) || ts.isPropertyDeclaration(node) || ts.isPropertyAssignment(node);
             }
             function createPropertyName(name, originalName) {
                 return ts.isIdentifier(originalName) ? ts.createIdentifier(name) : ts.createLiteral(name);
@@ -123457,7 +123466,7 @@ var ts;
                 }
             }
             function insertAccessor(changeTracker, file, accessor, declaration, container) {
-                ts.isParameterPropertyDeclaration(declaration)
+                ts.isParameterPropertyDeclaration(declaration, declaration.parent)
                     ? changeTracker.insertNodeAtClassStart(file, container, accessor)
                     : ts.isPropertyAssignment(declaration)
                         ? changeTracker.insertNodeAfterComma(file, declaration, accessor)
diff --git a/lib/typingsInstaller.js b/lib/typingsInstaller.js
index 13642ef70ad95..d8bd3fffc950b 100644
--- a/lib/typingsInstaller.js
+++ b/lib/typingsInstaller.js
@@ -83,7 +83,7 @@ var ts;
     // If changing the text in this section, be sure to test `configureNightly` too.
     ts.versionMajorMinor = "3.6";
     /** The version of the TypeScript compiler release */
-    ts.version = ts.versionMajorMinor + ".3";
+    ts.version = ts.versionMajorMinor + ".4";
 })(ts || (ts = {}));
 (function (ts) {
     /* @internal */
@@ -9700,7 +9700,7 @@ var ts;
     }
     ts.isEnumConst = isEnumConst;
     function isDeclarationReadonly(declaration) {
-        return !!(ts.getCombinedModifierFlags(declaration) & 64 /* Readonly */ && !ts.isParameterPropertyDeclaration(declaration));
+        return !!(ts.getCombinedModifierFlags(declaration) & 64 /* Readonly */ && !ts.isParameterPropertyDeclaration(declaration, declaration.parent));
     }
     ts.isDeclarationReadonly = isDeclarationReadonly;
     function isVarConst(node) {
@@ -13409,8 +13409,8 @@ var ts;
         }
     }
     ts.getTypeParameterOwner = getTypeParameterOwner;
-    function isParameterPropertyDeclaration(node) {
-        return ts.hasModifier(node, 92 /* ParameterPropertyModifier */) && node.parent.kind === 158 /* Constructor */;
+    function isParameterPropertyDeclaration(node, parent) {
+        return ts.hasModifier(node, 92 /* ParameterPropertyModifier */) && parent.kind === 158 /* Constructor */;
     }
     ts.isParameterPropertyDeclaration = isParameterPropertyDeclaration;
     function isEmptyBindingPattern(node) {
@@ -30751,7 +30751,7 @@ var ts;
             }
             // If this is a property-parameter, then also declare the property symbol into the
             // containing class.
-            if (ts.isParameterPropertyDeclaration(node)) {
+            if (ts.isParameterPropertyDeclaration(node, node.parent)) {
                 var classDeclaration = node.parent.parent;
                 declareSymbol(classDeclaration.symbol.members, classDeclaration.symbol, node, 4 /* Property */ | (node.questionToken ? 16777216 /* Optional */ : 0 /* None */), 0 /* PropertyExcludes */);
             }
@@ -40109,8 +40109,7 @@ var ts;
             return undefined;
         }
         function getConstraintDeclaration(type) {
-            var decl = type.symbol && ts.getDeclarationOfKind(type.symbol, 151 /* TypeParameter */);
-            return decl && ts.getEffectiveConstraintOfTypeParameter(decl);
+            return ts.mapDefined(ts.filter(type.symbol && type.symbol.declarations, ts.isTypeParameterDeclaration), ts.getEffectiveConstraintOfTypeParameter)[0];
         }
         function getInferredTypeParameterConstraint(typeParameter) {
             var inferences;
@@ -40318,11 +40317,11 @@ var ts;
             }
             return undefined;
         }
-        function resolveTypeReferenceName(typeReferenceName, meaning) {
+        function resolveTypeReferenceName(typeReferenceName, meaning, ignoreErrors) {
             if (!typeReferenceName) {
                 return unknownSymbol;
             }
-            return resolveEntityName(typeReferenceName, meaning) || unknownSymbol;
+            return resolveEntityName(typeReferenceName, meaning, ignoreErrors) || unknownSymbol;
         }
         function getTypeReferenceType(node, symbol) {
             var typeArguments = typeArgumentsFromTypeReferenceNode(node); // Do unconditionally so we mark type arguments as referenced.
@@ -40497,7 +40496,16 @@ var ts;
                 var meaning = 788968 /* Type */;
                 if (isJSDocTypeReference(node)) {
                     type = getIntendedTypeFromJSDocTypeReference(node);
-                    meaning |= 111551 /* Value */;
+                    if (!type) {
+                        symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning, /*ignoreErrors*/ true);
+                        if (symbol === unknownSymbol) {
+                            symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning | 111551 /* Value */);
+                        }
+                        else {
+                            resolveTypeReferenceName(getTypeReferenceName(node), meaning); // Resolve again to mark errors, if any
+                        }
+                        type = getTypeReferenceType(node, symbol);
+                    }
                 }
                 if (!type) {
                     symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning);
@@ -41300,6 +41308,7 @@ var ts;
                         break;
                 }
             }
+            // tslint:disable no-unnecessary-type-assertion
             return links.resolvedType; // TODO: GH#18217
         }
         function createIndexedAccessType(objectType, indexType) {
@@ -55517,7 +55526,7 @@ var ts;
                 if (member.kind === 158 /* Constructor */) {
                     for (var _b = 0, _c = member.parameters; _b < _c.length; _b++) {
                         var param = _c[_b];
-                        if (ts.isParameterPropertyDeclaration(param) && !ts.isBindingPattern(param.name)) {
+                        if (ts.isParameterPropertyDeclaration(param, member) && !ts.isBindingPattern(param.name)) {
                             addName(instanceNames, param.name, param.name.escapedText, 3 /* GetOrSetAccessor */);
                         }
                     }
@@ -57089,7 +57098,7 @@ var ts;
                         var parameter = local.valueDeclaration && tryGetRootParameterDeclaration(local.valueDeclaration);
                         var name = local.valueDeclaration && ts.getNameOfDeclaration(local.valueDeclaration);
                         if (parameter && name) {
-                            if (!ts.isParameterPropertyDeclaration(parameter) && !ts.parameterIsThisKeyword(parameter) && !isIdentifierThatStartsWithUnderscore(name)) {
+                            if (!ts.isParameterPropertyDeclaration(parameter, parameter.parent) && !ts.parameterIsThisKeyword(parameter) && !isIdentifierThatStartsWithUnderscore(name)) {
                                 addDiagnostic(parameter, 1 /* Parameter */, ts.createDiagnosticForNode(name, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, ts.symbolName(local)));
                             }
                         }
@@ -58659,11 +58668,10 @@ var ts;
                     var constraint = ts.getEffectiveConstraintOfTypeParameter(source);
                     var sourceConstraint = constraint && getTypeFromTypeNode(constraint);
                     var targetConstraint = getConstraintOfTypeParameter(target);
-                    if (sourceConstraint) {
-                        // relax check if later interface augmentation has no constraint
-                        if (!targetConstraint || !isTypeIdenticalTo(sourceConstraint, targetConstraint)) {
-                            return false;
-                        }
+                    // relax check if later interface augmentation has no constraint, it's more broad and is OK to merge with
+                    // a more constrained interface (this could be generalized to a full heirarchy check, but that's maybe overkill)
+                    if (sourceConstraint && targetConstraint && !isTypeIdenticalTo(sourceConstraint, targetConstraint)) {
+                        return false;
                     }
                     // If the type parameter node has a default and it is not identical to the default
                     // for the type parameter at this position, we report an error.
@@ -62078,6 +62086,7 @@ var ts;
                 }
                 // Modifiers are never allowed on properties except for 'async' on a method declaration
                 if (prop.modifiers) {
+                    // tslint:disable no-unnecessary-type-assertion
                     for (var _b = 0, _c = prop.modifiers; _b < _c.length; _b++) { // TODO: GH#19955
                         var mod = _c[_b];
                         if (mod.kind !== 122 /* AsyncKeyword */ || prop.kind !== 157 /* MethodDeclaration */) {
@@ -70697,7 +70706,7 @@ var ts;
             var members = [];
             var constructor = ts.getFirstConstructorWithBody(node);
             var parametersWithPropertyAssignments = constructor &&
-                ts.filter(constructor.parameters, ts.isParameterPropertyDeclaration);
+                ts.filter(constructor.parameters, function (p) { return ts.isParameterPropertyDeclaration(p, constructor); });
             if (parametersWithPropertyAssignments) {
                 for (var _i = 0, parametersWithPropertyAssignments_1 = parametersWithPropertyAssignments; _i < parametersWithPropertyAssignments_1.length; _i++) {
                     var parameter = parametersWithPropertyAssignments_1[_i];
@@ -71544,7 +71553,7 @@ var ts;
         }
         function transformConstructorBody(body, constructor) {
             var parametersWithPropertyAssignments = constructor &&
-                ts.filter(constructor.parameters, ts.isParameterPropertyDeclaration);
+                ts.filter(constructor.parameters, function (p) { return ts.isParameterPropertyDeclaration(p, constructor); });
             if (!ts.some(parametersWithPropertyAssignments)) {
                 return ts.visitFunctionBody(body, visitor, context);
             }
@@ -72872,7 +72881,7 @@ var ts;
             if (constructor && constructor.body) {
                 var parameterPropertyDeclarationCount = 0;
                 for (var i = indexOfFirstStatement; i < constructor.body.statements.length; i++) {
-                    if (ts.isParameterPropertyDeclaration(ts.getOriginalNode(constructor.body.statements[i]))) {
+                    if (ts.isParameterPropertyDeclaration(ts.getOriginalNode(constructor.body.statements[i]), constructor)) {
                         parameterPropertyDeclarationCount++;
                     }
                     else {
@@ -84024,7 +84033,7 @@ var ts;
             return getReturnTypeVisibilityError;
         }
         else if (ts.isParameter(node)) {
-            if (ts.isParameterPropertyDeclaration(node) && ts.hasModifier(node.parent, 8 /* Private */)) {
+            if (ts.isParameterPropertyDeclaration(node, node.parent) && ts.hasModifier(node.parent, 8 /* Private */)) {
                 return getVariableDeclarationTypeVisibilityError;
             }
             return getParameterDeclarationTypeVisibilityError;