panic: runtime error: cgo argument has Go pointer to Go pointer

[zhengxiaochuan-3]

go version:
[root@node-65-76 nvme]# go version
go version go1.8.1 linux/amd64

goroutine 62 [running, locked to thread]:
github.com/armon/gomdb.(*Txn).Put.func1(0x7fc0d8001df0, 0xc400000002, 0xc420164490, 0xc4201644a0, 0x0, 0x0)
	/home/go-project/src/github.com/armon/gomdb/txn.go:152 +0x8b
github.com/armon/gomdb.(*Txn).Put(0xc42062a050, 0x2, 0xc420164430, 0x8, 0x8, 0xc420ea6000, 0x4d, 0x81, 0x0, 0x0, ...)
	/home/go-project/src/github.com/armon/gomdb/txn.go:152 +0xec
github.com/hashicorp/raft-mdb.(*MDBStore).StoreLogs(0xc42000c8c0, 0xc42062a038, 0x1, 0x1, 0x1, 0x1)
	/home/go-project/src/github.com/hashicorp/raft-mdb/mdb_store.go:223 +0x229
github.com/hashicorp/raft.(*Raft).dispatchLogs(0xc420190600, 0xc42006dea8, 0x1, 0x1)
	/home/go-project/src/github.com/hashicorp/raft/raft.go:1149 +0x3a3
github.com/hashicorp/raft.(*Raft).runLeader(0xc420190600)
	/home/go-project/src/github.com/hashicorp/raft/raft.go:861 +0x68a
github.com/hashicorp/raft.(*Raft).run(0xc420190600)
	/home/go-project/src/github.com/hashicorp/raft/raft.go:635 +0x84
github.com/hashicorp/raft.(*Raft).(github.com/hashicorp/raft.run)-fm()
	/home/go-project/src/github.com/hashicorp/raft/raft.go:259 +0x2a
github.com/hashicorp/raft.(*raftState).goFunc.func1(0xc420190600, 0xc42061e450)
	/home/go-project/src/github.com/hashicorp/raft/state.go:146 +0x53
created by github.com/hashicorp/raft.(*raftState).goFunc
	/home/go-project/src/github.com/hashicorp/raft/state.go:147 +0x66
2017/08/14 11:58:30 [DEBUG] raft-net: 127.0.0.1:12001 accepted connection from: 127.0.0.1:58652
panic: runtime error: cgo argument has Go pointer to Go pointer

[tylertreat]

I just ran across the same issue. I think this library might need to be updated to work with newer versions of Go?

[freeekanayaka]

@tylertreat right, it violates cgo pointer rules rules, which have always been there but now have runtime checks in Go 1.8.

Can upstream make a comment on this? It seems this bug pretty much makes the lmdb backend for the raft package unusable with Go 1.8 (and the lmdb backend is the recommended one).

[tylertreat]

FWIW, it looks like Consul uses https://github.com/hashicorp/raft-boltdb for its Raft backend, so I wonder if that is the "recommended" one now.

[freeekanayaka]

@tylertreat if it's not anymore, I'd say the raft README should be updated:

"To prevent complications with cgo, the primary backend MDBStore is in a separate repository, called raft-mdb. That is the recommended implementation for the LogStore and StableStore."