roasbeef/btcd does not start with chain data created by btcsuite/btcd

[offerm]

Background
I'm trying to setup LND for mainnet. For that I setup a btcd server. By mistake I used btcsuite/btcd to download the blockchain.
To use it with LND I setup roasbeef/btcd using the data directory created by btcsuite/btcd. I was expected that it will work without any problem.
However, when I start roasbeef/btcd it fails with the following:

2018-04-07 23:19:36.566 [INF] BTCD: Version 0.12.0-beta
2018-04-07 23:19:36.602 [INF] BTCD: Loading block database from '/Users/admin/Library/Application Support/Btcd/data/mainnet/blocks_ffldb'
2018-04-07 23:19:37.366 [INF] BTCD: Block database loaded
2018-04-07 23:19:37.376 [INF] INDX: cf index is enabled
2018-04-07 23:19:37.377 [INF] CHAN: Loading block index. This might take a while...
2018-04-07 23:19:37.486 [INF] BTCD: Gracefully shutting down the database...
2018-04-07 23:19:37.487 [INF] BTCD: Shutdown complete
panic: runtime error: slice bounds out of range [recovered]
panic: runtime error: slice bounds out of range

goroutine 1 [running]:
github.com/roasbeef/btcd/database/ffldb.rollbackOnPanic(0xc4201b4120)
/Users/admin/gocode/src/github.com/roasbeef/btcd/database/ffldb/db.go:1889 +0x77
panic(0x159e840, 0x1ab3070)
/usr/local/Cellar/go/1.10/libexec/src/runtime/panic.go:505 +0x229
github.com/roasbeef/btcd/database/ffldb.(*transaction).FetchBlockHeader(0xc4201b4120, 0xc420150160, 0x373a7f0, 0x20, 0xc420150140, 0xc420154080, 0xc420150160)
/Users/admin/gocode/src/github.com/roasbeef/btcd/database/ffldb/db.go:1278 +0x2bc
github.com/roasbeef/btcd/blockchain.dbFetchHeaderByHash(0x17ff6c0, 0xc4201b4120, 0xc420150160, 0xc420150160, 0x0, 0x0)
/Users/admin/gocode/src/github.com/roasbeef/btcd/blockchain/chainio.go:1231 +0x3f
github.com/roasbeef/btcd/blockchain.dbFetchHeaderByHeight(0x17ff6c0, 0xc4201b4120, 0x0, 0xc422470000, 0x7e3c9, 0x7e3c9)
/Users/admin/gocode/src/github.com/roasbeef/btcd/blockchain/chainio.go:1253 +0x8f
github.com/roasbeef/btcd/blockchain.(*BlockChain).initChainState.func1(0x17ff6c0, 0xc4201b4120, 0xc4201b4120, 0x0)
/Users/admin/gocode/src/github.com/roasbeef/btcd/blockchain/chainio.go:1159 +0x37d
github.com/roasbeef/btcd/database/ffldb.(*db).View(0xc42002e700, 0xc42015e220, 0x0, 0x0)
/Users/admin/gocode/src/github.com/roasbeef/btcd/database/ffldb/db.go:1912 +0x9b
github.com/roasbeef/btcd/blockchain.(*BlockChain).initChainState(0xc4204f4f00, 0xc4204f4f00, 0xc420571728)
/Users/admin/gocode/src/github.com/roasbeef/btcd/blockchain/chainio.go:1134 +0x99
github.com/roasbeef/btcd/blockchain.New(0xc42050a310, 0xc42050a310, 0x12, 0x0)
/Users/admin/gocode/src/github.com/roasbeef/btcd/blockchain/chain.go:1600 +0x528
main.newServer(0xc42014a190, 0x1, 0x1, 0x17fc0e0, 0xc42002e700, 0x1abbd20, 0xc42009a120, 0xc42015e600, 0xc42015e5e0, 0xc420152650)
/Users/admin/gocode/src/github.com/roasbeef/btcd/server.go:2412 +0x8d9
main.btcdMain(0x0, 0x0, 0x0)
/Users/admin/gocode/src/github.com/roasbeef/btcd/btcd.go:148 +0x686
main.main()
/Users/admin/gocode/src/github.com/roasbeef/btcd/btcd.go:330 +0xd0

Process finished with exit code 2

Your environment
Running on Darwin admins-MacBook-Pro-2.local 16.7.0 Darwin Kernel Version 16.7.0: Thu Jun 15 17:36:27 PDT 2017; root:xnu-3789.70.16~2/RELEASE_X86_64 x86_64
btcd version 0.12.0-beta

Steps to reproduce
Very easy for me to reproduce. Just start btcd.
If I use btcsuite/btcd it will start successfully.

Expected behaviour
Should start without errors

Actual behaviour
See above.

From debugging:
When loading block index at chainio.go
calling dbFetchHeaderByHeight with height=0 (first block)
getting correct has for height =0
calling dbFetchHeaderByHash with hash
calling FetchBlockHeader with hash
calling fetchBlockRow with hash
getting a blockrow from hash table using the Hash

               returned blockrow has length of 12 which is causing a failure at db.go:1278

[Roasbeef]

The index formats of my fork, and upstream btcd have diverged. As a result, the chain indexes are currently incompatible. If you're not using neutrino, then you can safely use upstream btcd .