这是什么错误？是游戏错误还是引擎错误？？？？
TypeError: Cannot read property ‘_texture’ of null
at cc_Label._activateMaterial (/Applications/CocosCreator2.1.2-apla.app/Contents/Resources/engine/bin/.cache/dev/cocos2d/core/components/CCLabel.js:421:64)
at cc_Label.set (/Applications/CocosCreator2.1.2-apla.app/Contents/Resources/engine/bin/.cache/dev/cocos2d/core/components/CCRenderComponent.js:44:30)
at cc_Label.n.set (/Applications/CocosCreator2.1.2-apla.app/Contents/Resources/app.asar/editor/page/scene-utils/lib/asset-watcher.js:1:903)
at cc_Label.n.set (/Applications/CocosCreator2.1.2-apla.app/Contents/Resources/app.asar/editor/page/scene-utils/lib/asset-watcher.js:1:903)
at cc_Label.n.set (/Applications/CocosCreator2.1.2-apla.app/Contents/Resources/app.asar/editor/page/scene-utils/lib/asset-watcher.js:1:903)
at cc_Label.n.set (/Applications/CocosCreator2.1.2-apla.app/Contents/Resources/app.asar/editor/page/scene-utils/lib/asset-watcher.js:1:903)
at cc_Label.n.set (/Applications/CocosCreator2.1.2-apla.app/Contents/Resources/app.asar/editor/page/scene-utils/lib/asset-watcher.js:1:903)
at cc_Label.n.set [as sharedMaterials] (/Applications/CocosCreator2.1.2-apla.app/Contents/Resources/app.asar/editor/page/scene-utils/lib/asset-watcher.js:1:903)
at l (/Applications/CocosCreator2.1.2-apla.app/Contents/Resources/app.asar/editor/page/scene-utils/utils/prefab.js:1:1837)
at d (/Applications/CocosCreator2.1.2-apla.app/Contents/Resources/app.asar/editor/page/scene-utils/utils/prefab.js:1:1394)