Crash.log

#
# A fatal error has been detected by the Java Runtime Environment:
#
#  EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x77227021, pid=6536, tid=3932
#
# JRE version: 6.0_17-b04
# Java VM: Java HotSpot(TM) Client VM (14.3-b01 mixed mode, sharing windows-x86 )
# Problematic frame:
# C  [ntdll.dll+0x67021]
#
# If you would like to submit a bug report, please visit:
#   http://java.sun.com/webapps/bugreport/crash.jsp
# The crash happened outside the Java Virtual Machine in native code.
# See problematic frame for where to report the bug.
#

---------------  T H R E A D  ---------------

Current thread (0x003d9400):  JavaThread "main" [_thread_in_native, id=3932, stack(0x00090000,0x00290000)]

siginfo: ExceptionCode=0xc0000005, reading address 0x00525e87

Registers:
EAX=0x00525e80, EBX=0x00510000, ECX=0x00001700, EDX=0x0051a680
ESP=0x0028a058, EBP=0x0028a084, ESI=0x00510000, EDI=0x00510000
EIP=0x77227021, EFLAGS=0x00010246

Top of Stack: (sp=0x0028a058)
0x0028a058:   00510000 0051a570 0051a680 0051b000
0x0028a068:   7724982e 771e8ea6 0000a000 00510000
0x0028a078:   0051b000 0000a000 00510000 0028a0c4
0x0028a088:   7724a38e 0051a680 0051a680 00001700
0x0028a098:   00000001 00510000 0051a570 00000000
0x0028a0a8:   ee000092 00000000 0051b038 0051b038
0x0028a0b8:   005100c4 00003bf8 0000077f 0028a1bc
0x0028a0c8:   771f3407 000007ff 0051a680 0028a18c 

Instructions: (pc=0x77227021)
0x77227011:   00 00 01 00 89 5d f0 8b 45 08 8b 4d 10 8d 04 c8
0x77227021:   80 78 07 03 89 45 ec 0f 84 14 02 00 00 83 65 f4 


Stack: [0x00090000,0x00290000],  sp=0x0028a058,  free space=2024k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
C  [ntdll.dll+0x67021]
C  [ntdll.dll+0x8a38e]
C  [ntdll.dll+0x33407]
C  [ntdll.dll+0x332f2]
C  [msvcrt.dll+0x98cd]
C  [jffi-0.6.dll+0x2bdd]
C  [jffi-0.6.dll+0x32d3]
j  com.kenai.jffi.Foreign.invokeArrayO1Int32(J[BLjava/lang/Object;III)I+0
j  com.kenai.jffi.Invoker.invokeArrayWithObjectsInt32(Lcom/kenai/jffi/Function;Lcom/kenai/jffi/HeapInvocationBuffer;Lcom/kenai/jffi/ObjectBuffer;)I+76
j  com.kenai.jffi.Invoker.invokeInt(Lcom/kenai/jffi/Function;Lcom/kenai/jffi/HeapInvocationBuffer;)I+13
j  org.jruby.ext.posix.WindowsLibC$jaffl$0._wmkdir([BI)I+26
j  org.jruby.ext.posix.WindowsPOSIX.mkdir(Ljava/lang/String;I)I+20
j  org.jruby.ext.posix.LazyPOSIX.mkdir(Ljava/lang/String;I)I+6
j  org.jruby.RubyDir.mkdirCommon(Lorg/jruby/Ruby;Ljava/lang/String;[Lorg/jruby/runtime/builtin/IRubyObject;)Lorg/jruby/runtime/builtin/IRubyObject;+88
j  org.jruby.RubyDir.mkdir(Lorg/jruby/runtime/builtin/IRubyObject;[Lorg/jruby/runtime/builtin/IRubyObject;)Lorg/jruby/runtime/builtin/IRubyObject;+27
j  org.jruby.RubyDir$s_method_0_1$RUBYINVOKER$mkdir.call(Lorg/jruby/runtime/ThreadContext;Lorg/jruby/runtime/builtin/IRubyObject;Lorg/jruby/RubyModule;Ljava/lang/String;[Lorg/jruby/runtime/builtin/IRubyObject;)Lorg/jruby/runtime/builtin/IRubyObject;+36
J  org.jruby.internal.runtime.methods.JavaMethod$JavaMethodN.call(Lorg/jruby/runtime/ThreadContext;Lorg/jruby/runtime/builtin/IRubyObject;Lorg/jruby/RubyModule;Ljava/lang/String;Lorg/jruby/runtime/builtin/IRubyObject;Lorg/jruby/runtime/Block;)Lorg/jruby/runtime/builtin/IRubyObject;
J  org.jruby.internal.runtime.methods.DynamicMethod.call(Lorg/jruby/runtime/ThreadContext;Lorg/jruby/runtime/builtin/IRubyObject;Lorg/jruby/RubyModule;Ljava/lang/String;Lorg/jruby/runtime/builtin/IRubyObject;)Lorg/jruby/runtime/builtin/IRubyObject;
J  org.jruby.runtime.callsite.CachingCallSite.call(Lorg/jruby/runtime/ThreadContext;Lorg/jruby/runtime/builtin/IRubyObject;Lorg/jruby/runtime/builtin/IRubyObject;Lorg/jruby/runtime/builtin/IRubyObject;)Lorg/jruby/runtime/builtin/IRubyObject;
j  ruby.jit.ruby.D_3a_.work.jruby_minus_dev.jruby.lib.ruby.$1_dot_8.fileutils.fu_mkdir33393055_9420495.__file__(Lruby/jit/ruby/D_3a_/work/jruby_minus_dev/jruby/lib/ruby/$1_dot_8/fileutils/fu_mkdir33393055_9420495;Lorg/jruby/runtime/ThreadContext;Lorg/jruby/runtime/builtin/IRubyObject;Lorg/jruby/runtime/builtin/IRubyObject;Lorg/jruby/runtime/builtin/IRubyObject;Lorg/jruby/runtime/Block;)Lorg/jruby/runtime/builtin/IRubyObject;+208
j  ruby.jit.ruby.D_3a_.work.jruby_minus_dev.jruby.lib.ruby.$1_dot_8.fileutils.fu_mkdir33393055_9420495.__file__(Lorg/jruby/runtime/ThreadContext;Lorg/jruby/runtime/builtin/IRubyObject;Lorg/jruby/runtime/builtin/IRubyObject;Lorg/jruby/runtime/builtin/IRubyObject;Lorg/jruby/runtime/Block;)Lorg/jruby/runtime/builtin/IRubyObject;+8
J  org.jruby.internal.runtime.methods.JittedMethod.call(Lorg/jruby/runtime/ThreadContext;Lorg/jruby/runtime/builtin/IRubyObject;Lorg/jruby/RubyModule;Ljava/lang/String;Lorg/jruby/runtime/builtin/IRubyObject;Lorg/jruby/runtime/builtin/IRubyObject;)Lorg/jruby/runtime/builtin/IRubyObject;
j  

WindowsLibC.java

public int _wmkdir(byte[] path);

WindowsPOSIX.java

    @Override
    public int mkdir(String path, int mode) {
        try {
            byte[] widePath = appendWcharNul(path.getBytes("UTF-16LE"));
            int res = ((WindowsLibC)libc())._wmkdir(widePath);
            if (res < 0) {
                int error = errno();
                handler.error(mapErrorToErrno(error), path);
            }
            return res;
        } catch (UnsupportedEncodingException e) {
            // should not really happen
            handler.error(Errno.EINVAL, path);
            return -1;
        }
    }

    private static byte[] appendWcharNul(byte[] bytes) {
        // adding two zero bytes at the end --> CRASH
        // adding only ONE zery byte --> OK, but WHY? :)
        byte[] withNul = new byte[bytes.length + 2];
        System.arraycopy(bytes, 0, withNul, 0, bytes.length);
        return withNul;