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Invalid memory access411:32, 13 November 2011

Invalid memory access

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Return to Thread:Talk:Hamilton/Invalid memory access.

By the nature of the Java language/vm itself, it should be 100% impossible for any Java code to cause a segfault...

Before looking deeper into it, this looks to me like a bug in your JVM Voidious.

Rednaxela06:25, 25 September 2011
 

In general, yes, and that was my first impression - I'm guessing Darkcanuck and I are both on Macs using the Apple JVM. But there are some special cases, like JNI and direct ByteBuffers, that give Java more direct access to memory stuff - maybe Robocode uses some such special feature and Hamilton is exposing a bug in Robocode?

Voidious06:35, 25 September 2011
 

Hamilton runs just fine here, and I looked over the entirety of Hamilton's code and nothing looks particularly odd really...

No JNI is allowed for robocode bots, and direct ByteBuffers still only allow access to properly allocated memory. Robocode itself doesn't use JNI either unless the .NET plugin is involved. In any case Hamilton's code looks quite normal/typical (Though apparently using pre-saved data :P)

I'd suggest perhaps running it with both a Java debugger on the Java code, and GDB on the JVM itself. One of the two should reveal what's going on...

Rednaxela06:42, 25 September 2011
 

This bot crashes my Roborumble client. Also it's the only bot with 840 pairings. At the time of this writing, all other bots have 839 pairings. Should we remove it from the rumble maybe? -- PEZ 19:41, 12 November 2011 (UTC) Moved from main page

Nat Pavasant11:32, 13 November 2011