Concurrent decoding

[mash]

Hi, thank you for making this package, loading JSON files is now much faster.

Though we're seeing following SIGSEGV occasionally.

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x90 pc=0x13f2ad2]

goroutine 638 [running]:
github.com/goccy/go-json/internal/decoder.(*structDecoder).DecodeStream(0x0, 0xc001d02420, 0xc0163a2000?, 0xc001102000)
        /root/server/vendor/github.com/goccy/go-json/internal/decoder/struct.go:696 +0x3b2
github.com/goccy/go-json.(*Decoder).DecodeWithOption(0xc000c99548, {0x1c392e0, 0xc001102000}, {0x0, 0x0, 0x6122203a2265646f?})
        /root/server/vendor/github.com/goccy/go-json/decode.go:233 +0xe6
github.com/goccy/go-json.(*Decoder).Decode(...)
        /root/server/vendor/github.com/goccy/go-json/decode.go:199
github.com/org/server/models.ReadFile({0xc001a8e0c0, 0x2c})
        /root/server/models/repo.go:381 +0x399
github.com/org/server/models.(*Repo).visit(0xc0017ad220, {0xc000def800, 0x13}, {0xc001a8e0c0, 0x2c}, {0xc001a8e081?, 0xb?})
        /root/server/models/repo.go:479 +0xc5
github.com/org/server/models.(*Repo).load.func1({0xc001a8e0c0?, 0xc000db43a0?}, {0x252c1a8?, 0xc00018c820?})
        /root/server/models/repo.go:606 +0x45
github.com/saracen/walker.(*walker).walk(0xc001e171c0, {0xc000db43a0, 0x20}, {0x252c1a8, 0xc00018c820})
        /root/server/vendor/github.com/saracen/walker/walker.go:76 +0x85
github.com/saracen/walker.(*walker).readdir(0xc001e171c0?, {0xc000db43a0, 0x20})
        /root/server/vendor/github.com/saracen/walker/walker_unix.go:46 +0x3b2
github.com/saracen/walker.(*walker).gowalk(0xc001e171c0, {0xc000db43a0, 0x20})
        /root/server/vendor/github.com/saracen/walker/walker.go:118 +0x25
github.com/saracen/walker.(*walker).walk.func1()
        /root/server/vendor/github.com/saracen/walker/walker.go:103 +0x1f
golang.org/x/sync/errgroup.(*Group).Go.func1()
        /root/server/vendor/golang.org/x/sync/errgroup/errgroup.go:75 +0x56
created by golang.org/x/sync/errgroup.(*Group).Go in goroutine 633
        /root/server/vendor/golang.org/x/sync/errgroup/errgroup.go:72 +0x96
FAIL    github.com/org/server/cli/cmd/repo       1.564s

We're using github.com/saracen/walker to read a lot of JSON files in parallel,
and seems to be hitting the CompileToGetDecoder race condition.

Is there a workaround or fix to this issue?