The JVM crashes in the GC because the destroys the length fields of the array it uses as the destination.

One example of the failures you see with this:
# guarantee(p == top()) failed: end of last object must match end of space
...
V [libjvm.so+0x147e054] ContiguousSpace::verify() const+0x1e0 (space.cpp:95)
V [libjvm.so+0x974118] DefNewGeneration::verify()+0x18 (defNewGeneration.cpp:834)
V [libjvm.so+0x1448a88] SerialHeap::verify(VerifyOption)+0x78 (serialHeap.cpp:881)
V [libjvm.so+0x15d9cd0] Universe::verify(VerifyOption, char const*)+0x490 (universe.cpp:1240)
V [libjvm.so+0x1673890] VM_Exit::doit()+0xa0 (universe.hpp:349)