bound must be positive

java.lang.IllegalArgumentException: bound must be positive
at java.util.Random.nextInt(Unknown Source)
at ary.a(SourceFile:139)
at ary.a(SourceFile:49)
at arm.a(SourceFile:389)
at asa.a(SourceFile:29)
at bgv.a(SourceFile:472)
at qs.a(SourceFile:174)
at bfh.a(SourceFile:843)
at qs.c(SourceFile:104)
at qs.d(SourceFile:116)
at aqu.a(SourceFile:276)
at arg.a(SourceFile:159)
at arg.a(SourceFile:80)
at qt.c(SourceFile:182)
at net.minecraft.server.MinecraftServer.z(SourceFile:599)
at net.minecraft.server.MinecraftServer.y(SourceFile:531)
at cyk.y(SourceFile:155)
at net.minecraft.server.MinecraftServer.run(SourceFile:447)
at java.lang.Thread.run(Unknown Source)

code:
<code>
i5 = this.b.nextInt(this.a.m(this.c.a(i3, 0, i4)).o() + 32);

// suggest:

i5 = Math.abs(this.b.nextInt(this.a.m(this.c.a(i3, 0, i4)).o() + 32));
</code>
What I expected to happen was...:
Describe what you thought should happen here

What actually happened was...:
apparently works when difficulty=peaceful.
map seems corrupt or outdated as doors displaced as half door.
other worlds worked fine.

Steps to Reproduce: Unkown
What file is ary.java in 1.8.1? The Entity.java?
ary -> arz 1.8.1-pre3 (implicates one file added in category a/r/)