Internal error

[003dec6d3298a70795db2007] /gramwiki/?title=Template:Character_and_All_Pinyin&diff=19433&oldid=18655 RuntimeException from line 58 of /var/www/mediawiki/root/extensions/SemanticMediaWiki/src/SQLStore/Lookup/SingleEntityQueryLookup.php: Expected a ValueDescription instance!

Backtrace:

#0 /var/www/mediawiki/root/extensions/SemanticMediaWiki/includes/query/SMW_QueryProcessor.php(338): SMW\SQLStore\Lookup\SingleEntityQueryLookup->getQueryResult(SMWQuery)
#1 /var/www/mediawiki/root/extensions/SemanticMediaWiki/src/ParserFunctions/AskParserFunction.php(364): SMWQueryProcessor::getResultFromQuery(SMWQuery, array, integer, integer)
#2 /var/www/mediawiki/root/extensions/SemanticMediaWiki/src/ParserFunctions/AskParserFunction.php(197): SMW\ParserFunctions\AskParserFunction->doFetchResultsFromFunctionParameters(array, array)
#3 /var/www/mediawiki/root/extensions/SemanticMediaWiki/src/ParserFunctions/ShowParserFunction.php(45): SMW\ParserFunctions\AskParserFunction->parse(array)
#4 /var/www/mediawiki/root/extensions/SemanticMediaWiki/src/ParserFunctionFactory.php(428): SMW\ParserFunctions\ShowParserFunction->parse(array)
#5 /var/www/mediawiki/root/includes/parser/Parser.php(3528): SMW\ParserFunctionFactory->SMW\{closure}(Parser, string, string, string, string)
#6 /var/www/mediawiki/root/includes/parser/Parser.php(3235): Parser->callParserFunction(PPTemplateFrame_DOM, string, array)
#7 /var/www/mediawiki/root/includes/parser/Preprocessor_DOM.php(1285): Parser->braceSubstitution(array, PPTemplateFrame_DOM)
#8 /var/www/mediawiki/root/includes/parser/Parser.php(3152): PPFrame_DOM->expand(DOMElement)
#9 /var/www/mediawiki/root/includes/parser/Preprocessor_DOM.php(1285): Parser->braceSubstitution(array, PPTemplateFrame_DOM)
#10 /var/www/mediawiki/root/includes/parser/Parser.php(3152): PPFrame_DOM->expand(DOMElement)
#11 /var/www/mediawiki/root/includes/parser/Preprocessor_DOM.php(1285): Parser->braceSubstitution(array, PPTemplateFrame_DOM)
#12 /var/www/mediawiki/root/includes/parser/Parser.php(3152): PPFrame_DOM->expand(DOMElement)
#13 /var/www/mediawiki/root/includes/parser/Preprocessor_DOM.php(1285): Parser->braceSubstitution(array, PPTemplateFrame_DOM)
#14 /var/www/mediawiki/root/includes/parser/Parser.php(3409): PPFrame_DOM->expand(DOMElement)
#15 /var/www/mediawiki/root/includes/parser/Preprocessor_DOM.php(1285): Parser->braceSubstitution(array, PPFrame_DOM)
#16 /var/www/mediawiki/root/extensions/Arrays/Arrays.php(351): PPFrame_DOM->expand(DOMElement)
#17 /var/www/mediawiki/root/includes/parser/Parser.php(3528): ExtArrays::pfObj_arrayprint(Parser, PPFrame_DOM, array)
#18 /var/www/mediawiki/root/includes/parser/Parser.php(3235): Parser->callParserFunction(PPFrame_DOM, string, array)
#19 /var/www/mediawiki/root/includes/parser/Preprocessor_DOM.php(1285): Parser->braceSubstitution(array, PPFrame_DOM)
#20 /var/www/mediawiki/root/includes/parser/Parser.php(3049): PPFrame_DOM->expand(DOMElement, integer)
#21 /var/www/mediawiki/root/includes/parser/Parser.php(1359): Parser->replaceVariables(string)
#22 /var/www/mediawiki/root/includes/parser/Parser.php(491): Parser->internalParse(string)
#23 /var/www/mediawiki/root/includes/content/WikitextContent.php(369): Parser->parse(string, Title, ParserOptions, boolean, boolean, integer)
#24 /var/www/mediawiki/root/includes/content/AbstractContent.php(555): WikitextContent->fillParserOutput(Title, integer, ParserOptions, boolean, ParserOutput)
#25 /var/www/mediawiki/root/includes/Revision/RenderedRevision.php(265): AbstractContent->getParserOutput(Title, integer, ParserOptions, boolean)
#26 /var/www/mediawiki/root/includes/Revision/RenderedRevision.php(234): MediaWiki\Revision\RenderedRevision->getSlotParserOutputUncached(WikitextContent, boolean)
#27 /var/www/mediawiki/root/includes/Revision/RevisionRenderer.php(193): MediaWiki\Revision\RenderedRevision->getSlotParserOutput(string)
#28 /var/www/mediawiki/root/includes/Revision/RevisionRenderer.php(142): MediaWiki\Revision\RevisionRenderer->combineSlotOutput(MediaWiki\Revision\RenderedRevision, array)
#29 [internal function]: MediaWiki\Revision\RevisionRenderer->MediaWiki\Revision\{closure}(MediaWiki\Revision\RenderedRevision, array)
#30 /var/www/mediawiki/root/includes/Revision/RenderedRevision.php(197): call_user_func(Closure, MediaWiki\Revision\RenderedRevision, array)
#31 /var/www/mediawiki/root/includes/poolcounter/PoolWorkArticleView.php(194): MediaWiki\Revision\RenderedRevision->getRevisionParserOutput()
#32 /var/www/mediawiki/root/includes/poolcounter/PoolCounterWork.php(123): PoolWorkArticleView->doWork()
#33 /var/www/mediawiki/root/includes/page/WikiPage.php(1254): PoolCounterWork->execute()
#34 /var/www/mediawiki/root/includes/diff/DifferenceEngine.php(922): WikiPage->getParserOutput(ParserOptions, integer)
#35 /var/www/mediawiki/root/includes/diff/DifferenceEngine.php(883): DifferenceEngine->getParserOutput(WikiPage, Revision)
#36 /var/www/mediawiki/root/includes/diff/DifferenceEngine.php(711): DifferenceEngine->renderNewRevision()
#37 /var/www/mediawiki/root/includes/page/Article.php(931): DifferenceEngine->showDiffPage(boolean)
#38 /var/www/mediawiki/root/includes/page/Article.php(615): Article->showDiffPage()
#39 /var/www/mediawiki/root/includes/actions/ViewAction.php(68): Article->view()
#40 /var/www/mediawiki/root/includes/MediaWiki.php(499): ViewAction->show()
#41 /var/www/mediawiki/root/includes/MediaWiki.php(294): MediaWiki->performAction(Article, Title)
#42 /var/www/mediawiki/root/includes/MediaWiki.php(865): MediaWiki->performRequest()
#43 /var/www/mediawiki/root/includes/MediaWiki.php(515): MediaWiki->main()
#44 /var/www/mediawiki/root/index.php(42): MediaWiki->run()
#45 {main}