Can manifest during parsing as the following crash:
Error mixing types: memory and NULL
# Internal Error (.../src/hotspot/share/opto/type.cpp:1117), pid=67432, tid=23299
# Error: ShouldNotReachHere()
Stack: [0x000070000df85000,0x000070000e085000], sp=0x000070000e07f9f0, free space=1002k
Native frames: (J=compiled Java code, A=aot compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.dylib+0x115d9ed] VMError::report_and_die(int, char const*, char const*, __va_list_tag*, Thread*, unsigned char*, void*, void*, char const*, int, unsigned long)+0x6dd
V [libjvm.dylib+0x115e00b] VMError::report_and_die(Thread*, void*, char const*, int, char const*, char const*, __va_list_tag*)+0x3b
V [libjvm.dylib+0x61247f] report_vm_error(char const*, int, char const*, char const*, ...)+0x13f
V [libjvm.dylib+0x10d84d7] Type::xmeet(Type const*) const+0x107
V [libjvm.dylib+0x10d82d7] Type::meet_helper(Type const*, bool) const+0xe7
V [libjvm.dylib+0xd8c9ab] MemNode::Ideal_common(PhaseGVN*, bool)+0x76b
V [libjvm.dylib+0xd977e2] LoadNode::Ideal(PhaseGVN*, bool)+0x22
V [libjvm.dylib+0xec8cda] PhaseIterGVN::transform_old(Node*)+0x12a
V [libjvm.dylib+0xec8796] PhaseIterGVN::optimize()+0x246
V [libjvm.dylib+0x5bf53c] Compile::inline_incrementally_cleanup(PhaseIterGVN&)+0x32c
V [libjvm.dylib+0x5bfe87] Compile::inline_incrementally(PhaseIterGVN&)+0x307
V [libjvm.dylib+0x5b95a8] Compile::Optimize()+0x2d8
V [libjvm.dylib+0x5b7b8d] Compile::Compile(ciEnv*, ciMethod*, int, bool, bool, bool, bool, DirectiveSet*)+0x188d