こんなかんじです tmp.naXATKx4$ swiftc foo.swift -g foo.swift:2:2: warning: expression of type 'Int' is unused a[0] ~^~~ foo.swift:2:2: warning: expression of type 'Int' is unused a[0] ~^~~ tmp.naXATKx4$ lldb ./foo (lldb) target create "./foo" Current executable set to '/var/folders/k2/q6yzck31253_q1j4kxkzq5jh0000gn/T/tmp.naXATKx4/foo' (arm64). (lldb) run Process 11150 launched: '/var/folders/k2/q6yzck31253_q1j4kxkzq5jh0000gn/T/tmp.naXATKx4/foo' (arm64) Swift/ContiguousArrayBuffer.swift:600: Fatal error: Index out of range 2022-11-30 14:06:07.610207+0900 foo[11150:3677660] Swift/ContiguousArrayBuffer.swift:600: Fatal error: Index out of range Process 11150 stopped * thread #1, queue = 'com.apple.main-thread', stop reason = Fatal error: Index out of range frame #0: 0x0000000193d93ae8 libswiftCore.dylib`_swift_runtime_on_report libswiftCore.dylib`: -> 0x193d93ae8 <+0>: ret libswiftCore.dylib`: 0x193d93aec <+0>: b 0x193d93ae8 ; _swift_runtime_on_report libswiftCore.dylib`: 0x193d93af0 <+0>: adrp x8, 308504 0x193d93af4 <+4>: ldrb w0, [x8, #0x6dc] Target 0: (foo) stopped. (lldb) thread backtrace * thread #1, queue = 'com.apple.main-thread', stop reason = Fatal error: Index out of range ... frame #8: 0x0000000100003f88 foo`main at foo.swift:2:2 frame #9: 0x00000001859a7e50 dyld`start + 2544 (lldb)
