Please answer these questions before submitting your issue. Thanks!

What version of Go are you using (go version)?

go version go1.8rc3 linux/amd64

What operating system and processor architecture are you using (go env)?

GOARCH="amd64"
GOBIN=""
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/root/go"
GORACE=""
GOROOT="/usr/local/go"
GOTOOLDIR="/usr/local/go/pkg/tool/linux_amd64"
GCCGO="gccgo"
CC="gcc"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build054843203=/tmp/go-build -gno-record-gcc-switches"
CXX="g++"
CGO_ENABLED="1"
PKG_CONFIG="pkg-config"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"

What did you do?

This crash happened 5 times in 9500 hours of runtime while running http://github.com/openai/go-vncdriver. It uses the CGO library to interface with Python.

What did you expect to see?

No crash. Or at least, a stack trace telling me what part of our code caused it. It's not impossible that our code tries to slice beyond an array, but in that case I'd expect to see a stack trace.

This is with go 1.8beta3, but I saw the same crash with go 1.7.4 (details at openai/universe#134)

I'm not sure how to start debugging this.

What did you see instead?

panic: runtime error: slice bounds out of range
fatal error: panic on system stack

runtime stack:
panic(0x7fb59dd9ed00, 0xc42001a0f0)
	/usr/local/go/src/runtime/panic.go:389 +0x6d6

goroutine 3 [running]:
panic: runtime error: slice bounds out of range
fatal error: panic on system stack
panic during panic

runtime stack:
panic(0x7fb59dd9ed00, 0xc42001a0f0)
	/usr/local/go/src/runtime/panic.go:389 +0x6d6
panic(0x7fb59dd9ed00, 0xc42001a0f0)
	/usr/local/go/src/runtime/panic.go:389 +0x6d6