[antlr-interest] Antlr 3.0b5 - possible Bug in NFAToDFAConverter

alexander.berger at finnova.ch alexander.berger at finnova.ch
Fri Nov 17 06:56:54 PST 2006


Hi Everybody. 

I upgraded from antlr 3.0b4 to 3.0b5 and now the processing of my grammar
fails with the StackTrace below. Antlr is consuming a lot of memory (up to 
1GB), so it looks as if there is a serious problem in the NFA to DFA Converter.

So, can anybody please confirm this or am I the only one having this problem. The grammar producing this error is quite big but I will provide
it if someone wants to have a look at it.


Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
	at java.util.HashMap.resize(HashMap.java:462)
	at java.util.HashMap.addEntry(HashMap.java:755)
	at java.util.HashMap.put(HashMap.java:385)
	at java.util.HashSet.add(HashSet.java:200)
	at org.antlr.analysis.NFAToDFAConverter.closure(NFAToDFAConverter.java:618)
	at org.antlr.analysis.NFAToDFAConverter.closure(NFAToDFAConverter.java:748)
	at org.antlr.analysis.NFAToDFAConverter.closure(NFAToDFAConverter.java:748)
	at org.antlr.analysis.NFAToDFAConverter.closure(NFAToDFAConverter.java:748)
	at org.antlr.analysis.NFAToDFAConverter.closure(NFAToDFAConverter.java:704)
	at org.antlr.analysis.NFAToDFAConverter.closure(NFAToDFAConverter.java:669)
	at org.antlr.analysis.NFAToDFAConverter.closure(NFAToDFAConverter.java:457)
	at org.antlr.analysis.NFAToDFAConverter.findNewDFAStatesAndAddDFATransitions(NFAToDFAConverter.java:274)
	at org.antlr.analysis.NFAToDFAConverter.convert(NFAToDFAConverter.java:99)
	at org.antlr.analysis.DFA.<init>(DFA.java:219)
	at org.antlr.tool.Grammar.createLookaheadDFA(Grammar.java:826)
	at org.antlr.tool.Grammar.createLookaheadDFAs(Grammar.java:774)
	at org.antlr.codegen.Target.performGrammarAnalysis(Target.java:111)
	at org.antlr.codegen.CodeGenerator.genRecognizer(CodeGenerator.java:279)
	at org.antlr.Tool.processGrammar(Tool.java:329)
	at org.antlr.Tool.process(Tool.java:266)
	at org.antlr.Tool.main(Tool.java:69)



By the way. What is the official way to report bugs in antlr 3.0b* ?

Kind Regards
Alex
____________________________________________

finnova AG Bankware
Alexander Berger
SR-Peripheral-Team 

Sägestrasse 22, CH-5600 Lenzburg
Tel: +41 62 886 4807 / Fax: +41 62 886 4888 mailto:alexander.berger at finnova.ch
http://www.finnova.ch 



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