diff --git a/src/vs/platform/instantiation/common/instantiation.ts b/src/vs/platform/instantiation/common/instantiation.ts
index 10ff5a25051df16adb010ea4baaf8b42eabc4f77..7e130cc39632884a7e2c0e57e90b41a85645d73a 100644
--- a/src/vs/platform/instantiation/common/instantiation.ts
+++ b/src/vs/platform/instantiation/common/instantiation.ts
@@ -29,7 +29,7 @@ export interface IConstructorSignature0<T> {
 }
 
 export interface IConstructorSignature1<A1, T> {
-	new(first: A1, ...services: BrandedService[]): T;
+	new <Services extends BrandedService[]>(first: A1, ...services: Services): T;
 }
 
 export interface IConstructorSignature2<A1, A2, T> {
diff --git a/src/vs/workbench/contrib/preferences/browser/preferencesEditor.ts b/src/vs/workbench/contrib/preferences/browser/preferencesEditor.ts
index 60bcbfd4ba48ab7bdb85311ddda7f51b5f6223fd..a8865d6ec602db4f0b292eb9db61d03eb6861f1b 100644
--- a/src/vs/workbench/contrib/preferences/browser/preferencesEditor.ts
+++ b/src/vs/workbench/contrib/preferences/browser/preferencesEditor.ts
@@ -29,7 +29,7 @@ import { SelectionHighlighter } from 'vs/editor/contrib/multicursor/multicursor'
 import * as nls from 'vs/nls';
 import { ConfigurationTarget } from 'vs/platform/configuration/common/configuration';
 import { IContextKey, IContextKeyService } from 'vs/platform/contextkey/common/contextkey';
-import { IInstantiationService } from 'vs/platform/instantiation/common/instantiation';
+import { IInstantiationService, IConstructorSignature1 } from 'vs/platform/instantiation/common/instantiation';
 import { ILogService } from 'vs/platform/log/common/log';
 import { IEditorProgressService } from 'vs/platform/progress/common/progress';
 import { Registry } from 'vs/platform/registry/common/platform';
@@ -984,7 +984,7 @@ export class DefaultPreferencesEditor extends BaseTextEditor {
 	private static _getContributions(): IEditorContributionDescription[] {
 		const skipContributions = [FoldingController.ID, SelectionHighlighter.ID, FindController.ID];
 		const contributions = EditorExtensionsRegistry.getEditorContributions().filter(c => skipContributions.indexOf(c.id) === -1);
-		contributions.push({ id: DefaultSettingsEditorContribution.ID, ctor: DefaultSettingsEditorContribution });
+		contributions.push({ id: DefaultSettingsEditorContribution.ID, ctor: DefaultSettingsEditorContribution as IConstructorSignature1<ICodeEditor, editorCommon.IEditorContribution> });
 		return contributions;
 	}