```
"main" #1 prio=5 os_prio=31 tid=0x00007feef2802000 nid=0x1d03 runnable [0x000070000afdf000]
   java.lang.Thread.State: RUNNABLE
	at org.joni.OptExactInfo.concatStr(OptExactInfo.java:87)
	at org.joni.Analyser.optimizeNodeLeft(Analyser.java:2093)
	at org.joni.Analyser.optimizeNodeLeft(Analyser.java:2310)
	at org.joni.Analyser.optimizeNodeLeft(Analyser.java:2052)
	at org.joni.Analyser.setOptimizedInfoFromTree(Analyser.java:2346)
	at org.joni.Analyser.compile(Analyser.java:149)
	at org.joni.Regex.<init>(Regex.java:155)
	at org.joni.Regex.<init>(Regex.java:134)
	at org.jruby.RubyRegexp.makeRegexp(RubyRegexp.java:152)
	at org.jruby.RubyRegexp.getRegexpFromCache(RubyRegexp.java:162)
	at org.jruby.RubyRegexp.regexpInitialize(RubyRegexp.java:1058)
	at org.jruby.RubyRegexp.<init>(RubyRegexp.java:337)
	at org.jruby.RubyRegexp.newRegexpParser(RubyRegexp.java:365)