~ ➤ crystal --version
Crystal 0.21.1 (2017-03-14) LLVM 4.0.0
~ ➤ crystal eval 'require "socket"; require "socket/tcp_socket"; TCPSocket.new("hello", 0)'
Invalid memory access (signal 11) at address 0x0
[4486190123] *CallStack::print_backtrace:Int32 +107
[4486161591] __crystal_sigfault_handler +55
[140735515010346] _sigtramp +26
[140735492457349] _gai_simple +88
[140735492434315] search_addrinfo +179
[140735492419567] si_addrinfo +2255
[140735492417147] getaddrinfo +179
[4486349509] *TCPSocket#initialize<String, Int32, Nil, Nil>:Nil +709
[4486348787] *TCPSocket#initialize<String, Int32>:Nil +35
[4486348727] *TCPSocket::new<String, Int32>:TCPSocket +183
[4486139052] __crystal_main +1228
[4486161336] main +40
~ ➤ bcrystal eval 'require "socket"; require "socket/tcp_socket"; TCPSocket.new("hello", 0)'
Using compiled compiler at .build/crystal
No address found for hello:0 over TCP (Socket::Error)
0x104379885: *CallStack::unwind:Array(Pointer(Void)) at ??
0x104379821: *CallStack#initialize:Array(Pointer(Void)) at ??
0x1043797f8: *CallStack::new:CallStack at ??
0x104378631: *raise<Socket::Error>:NoReturn at ??
0x1043a6272: *TCPSocket#initialize<String, Int32, Nil, Nil>:Nil at ??
0x1043a5f53: *TCPSocket#initialize<String, Int32>:Nil at ??
0x1043a5f17: *TCPSocket::new<String, Int32>:TCPSocket at ??
0x104372bec: __crystal_main at ??
0x104378308: main at ??
~ ➤