runtime: stack grow panic tracing back through sigpanic from signal handler

[eliasnaur]

From https://build.golang.org/log/6864350004c318139a5516a5b65d5099a88a0272:

panic: runtime: unexpected return pc for runtime.exitsyscall called from 0x0
fatal error: unknown caller pc
panic during panic
runtime stack:
runtime.startpanic_m()
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/panic.go:688 +0x174
runtime.startpanic()
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/panic.go:589 +0x14
runtime.throw(0x100f5e61e, 0x11)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/panic.go:615 +0x54
runtime.gentraceback(0xffffffffffffffff, 0xffffffffffffffff, 0x0, 0x106ade300, 0x0, 0x0, 0x7fffffff, 0x100f65ab0, 0x16f0177e0, 0x0, ...)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/traceback.go:286 +0x14fc
runtime.copystack(0x106ade300, 0x1000, 0x1)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/stack.go:891 +0x1c4
runtime.newstack()
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/stack.go:1063 +0x254
runtime.morestack()
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/asm_arm64.s:297 +0x68

goroutine 40 [copystack]:
runtime.mapaccess1_fast32(0x100f31600, 0x0, 0x15dc0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/hashmap_fast.go:12 +0x1b8 fp=0x106b05b60 sp=0x106b05b60 pc=0x100df6818
runtime.resolveTypeOff(0x100f34880, 0x15dc0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/type.go:227 +0x70 fp=0x106b05bc0 sp=0x106b05b60 pc=0x100e38a70
runtime.(*_type).typeOff(0x100f34880, 0x100015dc0, 0x101039901)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/type.go:239 +0x28 fp=0x106b05be0 sp=0x106b05bc0 pc=0x100e38cf8
runtime.(*itab).init(0x10126cff0, 0x0, 0x101057ee0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/iface.go:193 +0x228 fp=0x106b05c90 sp=0x106b05be0 pc=0x100df9ec8
runtime.getitab(0x100f34880, 0x100f26c00, 0x1, 0x1)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/iface.go:69 +0x3b0 fp=0x106b05d10 sp=0x106b05c90 pc=0x100df99a0
runtime.assertE2I2(0x100f34880, 0x100f26c00, 0x106b21fe0, 0x106a20058, 0x106a10798, 0x100e16068)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/iface.go:592 +0x34 fp=0x106b05d40 sp=0x106b05d10 pc=0x100dfad04
runtime.printany(0x100f26c00, 0x106b21fe0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/error.go:78 +0x48 fp=0x106b05e40 sp=0x106b05d40 pc=0x100df2a98
runtime.printpanics(0x106b05ed8)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/panic.go:417 +0x58 fp=0x106b05e60 sp=0x106b05e40 pc=0x100e15108
panic(0x100f32260, 0x1010320c0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/panic.go:550 +0x398 fp=0x106b05f00 sp=0x106b05e60 pc=0x100e15528
runtime.panicmem()
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/panic.go:63 +0x5c fp=0x106b05f20 sp=0x106b05f00 pc=0x100e1425c
runtime.sigpanic()
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/signal_unix.go:382 +0x134 fp=0x106b05f70 sp=0x106b05f20 pc=0x100e2a0f4
runtime.exitsyscall(0x3b)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/proc.go:2973 +0x48 fp=0x106b05fb0 sp=0x106b05f80 pc=0x100e1dd68
created by log/syslog.TestConcurrentReconnect
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:351 +0x1d0

goroutine 1 [chan receive]:
testing.(*T).Run(0x106abc000, 0x100f5faef, 0x17, 0x100f65808, 0x5a5ae101)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/testing/testing.go:825 +0x258
testing.runTests.func1(0x106abc000)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/testing/testing.go:1063 +0x54
testing.tRunner(0x106abc000, 0x106a5ddd0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/testing/testing.go:777 +0xb0
testing.runTests(0x106a88180, 0x101036660, 0x8, 0x8, 0x100e3ab60)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/testing/testing.go:1061 +0x26c
testing.(*M).Run(0x106aba000, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/testing/testing.go:978 +0x14c
main.main()
	_testmain.go:58 +0x15c

goroutine 20 [chan receive]:
testing.(*T).Parallel(0x106abc0f0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/testing/testing.go:697 +0x17c
log/syslog.TestWithSimulated(0x106abc0f0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:137 +0x28
testing.tRunner(0x106abc0f0, 0x100f65840)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/testing/testing.go:777 +0xb0
created by testing.(*T).Run
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/testing/testing.go:824 +0x244

goroutine 8 [chan receive]:
testing.(*T).Parallel(0x106ac03c0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/testing/testing.go:697 +0x17c
log/syslog.TestWrite(0x106ac03c0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:266 +0x48
testing.tRunner(0x106ac03c0, 0x100f65848)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/testing/testing.go:777 +0xb0
created by testing.(*T).Run
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/testing/testing.go:824 +0x244

goroutine 38 [semacquire]:
sync.runtime_Semacquire(0x106a182cc)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/sema.go:56 +0x2c
sync.(*WaitGroup).Wait(0x106a182c0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/sync/waitgroup.go:129 +0x68
log/syslog.TestConcurrentReconnect(0x106ac05a0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:385 +0x260
testing.tRunner(0x106ac05a0, 0x100f65808)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/testing/testing.go:777 +0xb0
created by testing.(*T).Run
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/testing/testing.go:824 +0x244

goroutine 53 [runnable]:
log/syslog.runStreamSyslog.func1(0x106a18280, 0x106a621e0, 0x100f7be40, 0x106a0e090)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:74
created by log/syslog.runStreamSyslog
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:74 +0x6c

goroutine 46 [runnable]:
syscall.Syscall(0x4, 0x9, 0x106ab64c0, 0x3b, 0x3b, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/syscall/asm_darwin_arm64.s:13 +0x8
syscall.write(0x9, 0x106ab64c0, 0x3b, 0x40, 0x100e54400, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/syscall/zsyscall_darwin_arm64.go:1321 +0x48
syscall.Write(0x9, 0x106ab64c0, 0x3b, 0x40, 0x7ffffffe7534aa79, 0x0, 0x1)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/syscall/syscall_unix.go:181 +0x38
internal/poll.(*FD).Write(0x106ad0500, 0x106ab64c0, 0x3b, 0x40, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_unix.go:256 +0x104
net.(*netFD).Write(0x106ad0500, 0x106ab64c0, 0x3b, 0x40, 0x100f52bc0, 0x100e80e78, 0x101032210)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/fd_unix.go:220 +0x3c
net.(*conn).Write(0x106a92070, 0x106ab64c0, 0x3b, 0x40, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/net.go:188 +0x50
fmt.Fprintf(0x100f7a1a0, 0x106a92070, 0x100f5f69a, 0x16, 0x106afbda0, 0x7, 0x7, 0x3b, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/fmt/print.go:189 +0x7c
log/syslog.(*netConn).writeString(0x106a882c0, 0xe, 0x106ac8360, 0x12, 0x100f5bb9b, 0x3, 0x100f5bd25, 0x4, 0x100f5ba0f, 0x1, ...)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog.go:295 +0x424
log/syslog.(*Writer).write(0x106a62300, 0xe, 0x100f5bd25, 0x4, 0x4, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog.go:273 +0xa8
log/syslog.(*Writer).writeAndRetry(0x106a62300, 0x6, 0x100f5bd25, 0x4, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog.go:254 +0x124
log/syslog.(*Writer).Info(0x106a62300, 0x100f5bd25, 0x4, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog.go:236 +0x38
log/syslog.TestConcurrentReconnect.func3(0x106a182c0, 0x106a1e440, 0x106a182b0, 0xf, 0x106ac05a0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:377 +0x15c
created by log/syslog.TestConcurrentReconnect
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:368 +0x244

goroutine 47 [IO wait]:
internal/poll.runtime_pollWait(0x10126ca90, 0x77, 0x10126ca98)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/netpoll.go:173 +0x3c
internal/poll.(*pollDesc).wait(0x106aba898, 0x77, 0x106afc600, 0x106afc658, 0x106ab9901)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_poll_runtime.go:85 +0xa0
internal/poll.(*pollDesc).waitWrite(0x106aba898, 0x106aba800, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_poll_runtime.go:94 +0x30
internal/poll.(*FD).WaitWrite(0x106aba880, 0x106a86048, 0x106a86048)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_unix.go:440 +0x2c
net.(*netFD).connect(0x106aba880, 0x100f7b380, 0x106a86048, 0x0, 0x0, 0x100f7a360, 0x106ab9960, 0x0, 0x0, 0x0, ...)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/fd_unix.go:152 +0x1ec
net.(*netFD).dial(0x106aba880, 0x100f7b380, 0x106a86048, 0x100f7b9c0, 0x0, 0x100f7b9c0, 0x106a80ba0, 0x100ef2298, 0x106a86da0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/sock_posix.go:142 +0x98
net.socket(0x100f7b380, 0x106a86048, 0x100f5bb9e, 0x3, 0x2, 0x1, 0x0, 0x0, 0x100f7b9c0, 0x0, ...)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/sock_posix.go:93 +0x128
net.internetSocket(0x100f7b380, 0x106a86048, 0x100f5bb9e, 0x3, 0x100f7b9c0, 0x0, 0x100f7b9c0, 0x106a80ba0, 0x1, 0x0, ...)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/ipsock_posix.go:141 +0xbc
net.doDialTCP(0x100f7b380, 0x106a86048, 0x100f5bb9e, 0x3, 0x0, 0x106a80ba0, 0x101039120, 0x100f7b380, 0x106a86048)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/tcpsock_posix.go:62 +0x78
net.dialTCP(0x100f7b380, 0x106a86048, 0x100f5bb9e, 0x3, 0x0, 0x106a80ba0, 0x0, 0x100e51b68, 0x150993ee4291fdb0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/tcpsock_posix.go:58 +0xb0
net.dialSingle(0x100f7b380, 0x106a86048, 0x106aba800, 0x100f7ab00, 0x106a80ba0, 0x0, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/dial.go:547 +0x300
net.dialSerial(0x100f7b380, 0x106a86048, 0x106aba800, 0x106b179c0, 0x1, 0x1, 0x0, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/dial.go:515 +0x18c
net.(*Dialer).DialContext(0x106afcda8, 0x100f7b380, 0x106a86048, 0x100f5bb9e, 0x3, 0x106a182b0, 0xf, 0x0, 0x0, 0x0, ...)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/dial.go:397 +0x510
net.(*Dialer).Dial(0x106afcda8, 0x100f5bb9e, 0x3, 0x106a182b0, 0xf, 0x0, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/dial.go:320 +0x5c
net.Dial(0x100f5bb9e, 0x3, 0x106a182b0, 0xf, 0x106ac83c0, 0x12, 0x100f5bb9b, 0x3)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/dial.go:291 +0x58
log/syslog.(*Writer).connect(0x106a62360, 0xe, 0x100f5bd25)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog.go:162 +0x10c
log/syslog.(*Writer).writeAndRetry(0x106a62360, 0x6, 0x100f5bd25, 0x4, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog.go:258 +0x90
log/syslog.(*Writer).Info(0x106a62360, 0x100f5bd25, 0x4, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog.go:236 +0x38
log/syslog.TestConcurrentReconnect.func3(0x106a182c0, 0x106a1e440, 0x106a182b0, 0xf, 0x106ac05a0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:377 +0x15c
created by log/syslog.TestConcurrentReconnect
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:368 +0x244

goroutine 39 [IO wait]:
internal/poll.runtime_pollWait(0x10126cea0, 0x72, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/netpoll.go:173 +0x3c
internal/poll.(*pollDesc).wait(0x106ad0218, 0x72, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_poll_runtime.go:85 +0xa0
internal/poll.(*pollDesc).waitRead(0x106ad0218, 0xffffffffffffff00, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_poll_runtime.go:90 +0x30
internal/poll.(*FD).Accept(0x106ad0200, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_unix.go:372 +0x164
net.(*netFD).accept(0x106ad0200, 0x106a0e098, 0x0, 0x100e1e45c)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/fd_unix.go:238 +0x24
net.(*TCPListener).accept(0x106a0e038, 0x106a0e098, 0x100e3cc20, 0x106ae5f40)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/tcpsock_posix.go:136 +0x24
net.(*TCPListener).Accept(0x106a0e038, 0x100f65850, 0x106a18280, 0x106a621e0, 0x100f7be40)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/tcpsock.go:259 +0x34
log/syslog.runStreamSyslog(0x100f7b000, 0x106a0e038, 0x106a621e0, 0x106a18280)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:70 +0x80
log/syslog.startServer.func2(0x106a0e030, 0x100f7b000, 0x106a0e038, 0x106a621e0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:130 +0x68
created by log/syslog.startServer
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:128 +0x378

goroutine 51 [runnable]:
log/syslog.runStreamSyslog.func1(0x106a18280, 0x106a621e0, 0x100f7be40, 0x106a0e080)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:74
created by log/syslog.runStreamSyslog
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:74 +0x6c

goroutine 24 [IO wait]:
internal/poll.runtime_pollWait(0x10126c680, 0x72, 0x106b09000)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/netpoll.go:173 +0x3c
internal/poll.(*pollDesc).wait(0x106aba318, 0x72, 0xffffffffffffff00, 0x100f7a5c0, 0x101020f80)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_poll_runtime.go:85 +0xa0
internal/poll.(*pollDesc).waitRead(0x106aba318, 0x106b09000, 0x1000, 0x1000)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_poll_runtime.go:90 +0x30
internal/poll.(*FD).Read(0x106aba300, 0x106b09000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_unix.go:157 +0x198
net.(*netFD).Read(0x106aba300, 0x106b09000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/fd_unix.go:202 +0x3c
net.(*conn).Read(0x106a92040, 0x106b09000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/net.go:176 +0x50
bufio.(*Reader).fill(0x106afef58)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/bufio/bufio.go:100 +0x104
bufio.(*Reader).ReadSlice(0x106afef58, 0x100e5310a, 0x18, 0x106a2fdb8, 0x106a70d80, 0x100e53b78, 0x106aba300)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/bufio/bufio.go:341 +0x20
bufio.(*Reader).ReadBytes(0x106afef58, 0xbe8ed63f84bab50a, 0x12aed3521, 0x100f0de00, 0x1000, 0x100f26dc0, 0x106a2fe01)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/bufio/bufio.go:419 +0x48
bufio.(*Reader).ReadString(0x106a2ff58, 0x100a, 0x1000, 0x106b09000, 0x1000, 0x1000)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/bufio/bufio.go:459 +0x28
log/syslog.runStreamSyslog.func1(0x106a18280, 0x106a621e0, 0x100f7be40, 0x106a92040)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:79 +0x154
created by log/syslog.runStreamSyslog
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:74 +0x6c

goroutine 52 [runnable]:
log/syslog.runStreamSyslog.func1(0x106a18280, 0x106a621e0, 0x100f7be40, 0x106a0e088)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:74
created by log/syslog.runStreamSyslog
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:74 +0x6c

goroutine 26 [runnable]:
internal/poll.runtime_pollWait(0x10126c340, 0x72, 0x106b0b000)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/netpoll.go:173 +0x3c
internal/poll.(*pollDesc).wait(0x106aba418, 0x72, 0xffffffffffffff00, 0x100f7a5c0, 0x101020f80)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_poll_runtime.go:85 +0xa0
internal/poll.(*pollDesc).waitRead(0x106aba418, 0x106b0b000, 0x1000, 0x1000)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_poll_runtime.go:90 +0x30
internal/poll.(*FD).Read(0x106aba400, 0x106b0b000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_unix.go:157 +0x198
net.(*netFD).Read(0x106aba400, 0x106b0b000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/fd_unix.go:202 +0x3c
net.(*conn).Read(0x106a92050, 0x106b0b000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/net.go:176 +0x50
bufio.(*Reader).fill(0x106b00f58)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/bufio/bufio.go:100 +0x104
bufio.(*Reader).ReadSlice(0x106b00f58, 0x100e5310a, 0x18, 0x106a30db8, 0x106a71080, 0x100e53b78, 0x106aba400)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/bufio/bufio.go:341 +0x20
bufio.(*Reader).ReadBytes(0x106b00f58, 0xbe8ed63f84bb740a, 0x12aedf0a1, 0x100f0de00, 0x1000, 0x100f26dc0, 0x106a30e01)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/bufio/bufio.go:419 +0x48
bufio.(*Reader).ReadString(0x106a30f58, 0x100a, 0x1000, 0x106b0b000, 0x1000, 0x1000)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/bufio/bufio.go:459 +0x28
log/syslog.runStreamSyslog.func1(0x106a18280, 0x106a621e0, 0x100f7be40, 0x106a92050)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:79 +0x154
created by log/syslog.runStreamSyslog
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:74 +0x6c

goroutine 27 [runnable]:
internal/poll.runtime_pollWait(0x10126c270, 0x72, 0x106ad5000)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/runtime/netpoll.go:173 +0x3c
internal/poll.(*pollDesc).wait(0x106aba498, 0x72, 0xffffffffffffff00, 0x100f7a5c0, 0x101020f80)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_poll_runtime.go:85 +0xa0
internal/poll.(*pollDesc).waitRead(0x106aba498, 0x106ad5000, 0x1000, 0x1000)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_poll_runtime.go:90 +0x30
internal/poll.(*FD).Read(0x106aba480, 0x106ad5000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/internal/poll/fd_unix.go:157 +0x198
net.(*netFD).Read(0x106aba480, 0x106ad5000, 0x1000, 0x1000, 0x2503, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/fd_unix.go:202 +0x3c
net.(*conn).Read(0x106a92058, 0x106ad5000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/net.go:176 +0x50
bufio.(*Reader).fill(0x106a42f58)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/bufio/bufio.go:100 +0x104
bufio.(*Reader).ReadSlice(0x106a42f58, 0xa, 0x0, 0x5, 0x2, 0x4, 0x1)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/bufio/bufio.go:341 +0x20
bufio.(*Reader).ReadBytes(0x106a42f58, 0xbe8ed63f84abc50a, 0x12ade44e9, 0x100f0de00, 0x1000, 0x100f26dc0, 0x106a31601)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/bufio/bufio.go:419 +0x48
bufio.(*Reader).ReadString(0x106a31758, 0x100a, 0x1000, 0x106ad5000, 0x1000, 0x1000)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/bufio/bufio.go:459 +0x28
log/syslog.runStreamSyslog.func1(0x106a18280, 0x106a621e0, 0x100f7be40, 0x106a92058)
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:79 +0x154
created by log/syslog.runStreamSyslog
	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:74 +0x6c

The stack looks interesting to me. @aclements ?

[ianlancetaylor]

Interestingly, this looks like something that @aclements was just talking about: stack growth in the signal handler. I think the traceback is failing to correctly trace past the sigpanic call inserted by the signal handler.

If I'm right, this is not a regression, and it's hard to fix, so although I just set the milestone to 1.10 I'm going to redirect to 1.11.

[eliasnaur]

Thanks. If you're right, the issue title is misleading. Feel free to update it to whatever makes more sense.

[aclements]

I agree with Ian that the trace past sigpanic is clearly wrong. The argument to exitsyscall is never 0x3b, and if it had panicked at the claimed line, throwsplit would have been set and newstack would have aborted much earlier, so even the saved LR traceback got from the sigpanic frame is wrong.

Given that the traceback print is failing, it's no surprise that stack growth is panicking. This is eerily similar to #21431, which is almost certainly also involves traceback failing around a sigpanic, this time on mipsle. Maybe we're just setting up our injected sigpanic calls slightly wrong on LR machines? I thought surely we'd have a test for this, but I can't actually find one.

[gopherbot]

Change https://golang.org/cl/89016 mentions this issue: runtime: print hexdump on traceback failure

[eliasnaur]

I'm not sure this is the same issue, but here's another with hexdump included:

https://build.golang.org/log/cdc05ec757bc1a3625a1ae212dd827691c26a3be

panic: runtime error: invalid memory address or nil pointer dereference

[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x1005773a4]



goroutine 39 [running]:

sync.(*WaitGroup).state(...)

	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/sync/waitgroup.go:33

sync.(*WaitGroup).Add(0x0, 0x1)

	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/sync/waitgroup.go:54 +0x18

log/syslog.runStreamSyslog(0x0, 0x0, 0x10046fd9c, 0x0)

	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:73 +0x34

runtime: unexpected return pc for log/syslog.startServer.func2 called from 0xd

stack: frame={sp:0x1300d8780, fp:0x1300d87b0} stack=[0x1300d8000,0x1300d8800)

00000001300d8680:  00000001004a1874 <runtime.sigpanic+308>  000000010059e4e0 

00000001300d8690:  000000010069f170  00000001300f4b00 

00000001300d86a0:  00000001004bd8b8 <sync.(*WaitGroup).Add+24>  0000000130070a80 

00000001300d86b0:  0000000000000001  000000013000e0a0 

00000001300d86c0:  0000000100569b64 <net.(*TCPListener).Accept+52>  00000001300f4b00 

00000001300d86d0:  000000013000e0a0  0000000130070a80 

00000001300d86e0:  0000000000000000  00000001005773a4 <log/syslog.runStreamSyslog+52> 

00000001300d86f0:  00000001005773a4 <log/syslog.runStreamSyslog+52>  0000000130092050 

00000001300d8700:  00000001005773a4 <log/syslog.runStreamSyslog+52>  0000000000000000 

00000001300d8710:  0000000000000000  0000000000000020 

00000001300d8720:  0000000130070a80  00000001005773dc <log/syslog.runStreamSyslog+108> 

00000001300d8730:  0000000100579b38 <log/syslog.startServer.func2+104>  0000000000000000 

00000001300d8740:  0000000000000001  000000013000e0a0 

00000001300d8750:  0000000000000000  0000000000000000 

00000001300d8760:  00000001004a0c20 <runtime.sighandler+0>  0000000100658218 

00000001300d8770:  00000001005e7640  000000013000e0a0 

00000001300d8780: <000000000000000d  0000000000000000 

00000001300d8790:  0000000000000000  000000010046fd9c <runtime.mallocgc+1100> 

00000001300d87a0:  0000000000000000  0000000000000000 

00000001300d87b0: >0000000000000000  0000000000000000 

00000001300d87c0:  0000000000000000  0000000000000000 

00000001300d87d0:  0000000000000000  0000000000000000 

00000001300d87e0:  0000000000000000  0000000000000000 

00000001300d87f0:  00000001300d8780  0000000000000000 

log/syslog.startServer.func2(0x0, 0x0, 0x0, 0x0)

	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:130 +0x68

created by log/syslog.startServer

	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/log/syslog/syslog_test.go:128 +0x370

Process 489 exited with status = 2 (0x00000002) 
go_darwin_arm_exec: test timeout (test completion)

[eliasnaur]

And another:

https://build.golang.org/log/6063e6e67248b01c9eb0100afc611ac23e203797

 2018/04/14 12:57:43 http: WriteHeader called with X-Content-Type-Options:nosniff but no Content-Type

2018/04/14 12:57:43 http: TLS handshake error from 127.0.0.1:52401: remote error: tls: bad certificate

panic: runtime error: invalid memory address or nil pointer dereference

[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x10118fd78]



goroutine 3694 [running]:

net/http.(*Server).getDoneChan(0x56000080, 0x0)

	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/http/server.go:2495 +0x1c

net/http.(*Server).Serve(0x56000080, 0xfffffffffed741b4, 0xd4251a, 0xf7269f6f7e7f9, 0xffee5113709a7598)

	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/http/server.go:2777 +0x270

runtime: unexpected return pc for runtime.sighandler called from 0x10153f614

stack: frame={sp:0x130489fa0, fp:0x130489fa0} stack=[0x130489000,0x13048a000)

0000000130489ea0:  000000010118fd78 <net/http.(*Server).Serve+624>  00000001013187a0 

0000000130489eb0:  000000010118fd78 <net/http.(*Server).Serve+624>  00000001013f03a0 

0000000130489ec0:  000000013002c120  0000000130489ef8 

0000000130489ed0:  00000001013f03a0  000000013002c120 

0000000130489ee0:  0000000100f7bce8 <runtime.sighandler+0>  0000000056000080 

0000000130489ef0:  0000000000000000  0000000000000000 

0000000130489f00:  00000001013f0560  000000013039b1d0 

0000000130489f10:  0000000000000000  00000001010f8a00 <vendor/golang_org/x/crypto/curve25519.feMul+360> 

0000000130489f20:  0000000000000000  0000000000000000 

0000000130489f30:  0000000000000000  0000000000000000 

0000000130489f40:  00000001013f0560  0000000000000000 

0000000130489f50:  0000000000000000  0000000000000000 

0000000130489f60:  000000013039b1d0  0000000000000000 

0000000130489f70:  0000000130489f00  0000000000000000 

0000000130489f80:  0000000000000000  0000000000000000 

0000000130489f90:  0000000000000330  0000000130489fa0 

0000000130489fa0: >000000010153f614  0000000056000080 

0000000130489fb0:  fffffffffed741b4  0000000000d4251a 

0000000130489fc0:  000f7269f6f7e7f9  ffee5113709a7598 

0000000130489fd0:  ffd8b76fa340bae4  000000000002bd35 

0000000130489fe0:  00008d3520d782dc  00000000022e67ab 

0000000130489ff0:  ffffffffff624c7f  000000000030eef2 

created by net/http/httptest.(*Server).goServe

	/private/var/folders/f6/d2bhfqss2716nxm8gkv1fmb80000gn/T/workdir-host-darwin-amd64-eliasnaur-ios/go/src/net/http/httptest/server.go:278 +0x50

Process 514 exited with status = 2 (0x00000002)