I know this code doesn't make sense but it is part of a function that was crashing APL. I narrowed it down to the following:
⍎'→0⍴0'
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-- Stack trace at Token.cc:665
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0x7f503336bde5 __libc_start_main
0x43550d main
0x52623d Workspace::immediate_execution(bool)
0x462a8d Command::process_line()
0x461a0b Command::process_line(UCS_string&)
0x46c4e8 Executable::execute_body() const
0x4e0f50 StateIndicator::run()
0x48f2e6 Prefix::reduce_statements()
0x500a1b Token::Token(Token const&)
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