fatal error: unexpected signal during runtime execution

[rivo]

Posting this because it may be helpful to track down some bug (first time it happened to me and I can't reproduce it). My program crashed, it seems, during garbage collection. go version go1.5.1 linux/amd64 I believe the process used about 15GB of RAM when it crashed. May have been close to the limit (although I would've expected some swapping first which didn't seem to happen).

fatal error: unexpected signal during runtime execution
[signal 0xb code=0x1 addr=0xf1 pc=0x46ed0b]

runtime stack:
runtime.throw(0x9fa660, 0x2a)
    /usr/local/go/src/runtime/panic.go:527 +0x90 fp=0x7fdda230ad40 sp=0x7fdda230ad28
runtime.sigpanic()
    /usr/local/go/src/runtime/sigpanic_unix.go:12 +0x5a fp=0x7fdda230ad90 sp=0x7fdda230ad40
runtime.munmap(0x7fdd93d4b000, 0xc0b028, 0x4289bf, 0x7fdd93d4b000, 0xc0b028, 0xbf75a0, 0x7fdd93d4b000, 0x181605, 0x1853d3, 0x4281dc, ...)
    /usr/local/go/src/runtime/sys_linux_amd64.s:266 +0x1b fp=0x7fdda230ad98 sp=0x7fdda230ad90
runtime.sysFree(0x7fdd93d4b000, 0xc0b028, 0xbf75a0)
    /usr/local/go/src/runtime/mem_linux.go:103 +0x34 fp=0x7fdda230adb0 sp=0x7fdda230ad98
runtime.gcCopySpans()
    /usr/local/go/src/runtime/mgc.go:1600 +0xdf fp=0x7fdda230ade8 sp=0x7fdda230adb0
runtime.gcMark(0x7f3385d7f60f7)
    /usr/local/go/src/runtime/mgc.go:1415 +0x5c fp=0x7fdda230ae50 sp=0x7fdda230ade8
runtime.gc.func3()
    /usr/local/go/src/runtime/mgc.go:1089 +0x23 fp=0x7fdda230ae60 sp=0x7fdda230ae50
runtime.systemstack(0xc820523240)
    /usr/local/go/src/runtime/asm_amd64.s:262 +0x79 fp=0x7fdda230ae68 sp=0x7fdda230ae60
runtime.mstart()
    /usr/local/go/src/runtime/proc1.go:674 fp=0x7fdda230ae70 sp=0x7fdda230ae68

[ianlancetaylor]

Thanks. Almost certainly #13227 .