Fastdebug VM crashes with

# Internal Error (/BUILD_AREA/jdk6_18/hotspot/src/share/vm/opto/phaseX.hpp:66), pid=14269, tid=139697073654096
# Error: assert(_inserts <= _insert_limit,"hash table overflow")
#
# JRE version: 6.0_18-b07
# Java VM: Java HotSpot(TM) 64-Bit Server VM (16.0-b13-fastdebug mixed mode linux-amd64 )


Current thread (0x00007f0dbc03a000): JavaThread "CompilerThread0" daemon [_thread_in_native, id=14321, stack(0x00007f0dc2638000,0x00007f0dc2739000)]

Stack: [0x00007f0dc2638000,0x00007f0dc2739000], sp=0x00007f0dc2731310, free space=3e40000000000000018k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0xb84abc];; VMError::report_and_die()+0x26c
V [libjvm.so+0x48fa9e];; report_assertion_failure(char const*, int, char const*)+0x6e
V [libjvm.so+0x9cd019];; NodeHash::hash_insert(Node*)+0x139
V [libjvm.so+0x9cd26d];; NodeHash::grow()+0xad
V [libjvm.so+0x9ccdd4];; NodeHash::hash_find_insert(Node*)+0x184
V [libjvm.so+0x9d1e95];; PhaseIterGVN::transform_old(Node*)+0x425
V [libjvm.so+0x9d0e7c];; PhaseIterGVN::optimize()+0x14c
V [libjvm.so+0x413a2b];; Compile::Optimize()+0x85b
V [libjvm.so+0x40ddbe];; Compile::Compile(ciEnv*, C2Compiler*, ciMethod*, int, bool, bool)+0x9ee
V [libjvm.so+0x330c34];; C2Compiler::compile_method(ciEnv*, ciMethod*, int)+0xa4
V [libjvm.so+0x41fd39];; CompileBroker::invoke_compiler_on_method(CompileTask*)+0x4d9
V [libjvm.so+0x41f14d];; CompileBroker::compiler_thread_loop()+0x55d
V [libjvm.so+0xb1e883];; compiler_thread_entry(JavaThread*, Thread*)+0x13
V [libjvm.so+0xb13d15];; JavaThread::thread_main_inner()+0xd5
V [libjvm.so+0xb13bdd];; JavaThread::run()+0xfd
V [libjvm.so+0x9754c6];; java_start(Thread*)+0x166