Panic nil pointer when using popular ttlcache library

[sandoichi]

The following program sample.go triggers an unexpected result

package main

import (
	_ "github.com/jellydator/ttlcache/v3"
	"github.com/traefik/yaegi/interp"
	"github.com/traefik/yaegi/stdlib"
)

func main() {
	i := interp.New(interp.Options{
               // go mod vendor into ./src
		GoPath: ".",
	})

	i.Use(stdlib.Symbols)

	_, err := i.Eval(`import "github.com/jellydator/ttlcache/v3"`)
	if err != nil {
		panic(err)
	}

	_, err = i.Eval(`var cache *ttlcache.Cache[string, string]`)
	if err != nil {
		panic(err)
	}

}

Expected result

should run without issue

Got

❯ go run .
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x128 pc=0x6d49df]

goroutine 1 [running]:
github.com/traefik/yaegi/interp.nodeType2(0xc0000ff448, 0xc000184c60, 0xc000537180, {0xc0004b8bc0, 0x3, 0x4})
	/home/chris/go/pkg/mod/github.com/traefik/yaegi@v0.16.1/interp/type.go:1083 +0x397f
github.com/traefik/yaegi/interp.nodeType2(0xc0000ff448, 0xc000184c60, 0xc000536c80, {0xc0004b8bc0, 0x2, 0x4})
	/home/chris/go/pkg/mod/github.com/traefik/yaegi@v0.16.1/interp/type.go:1079 +0x3957
github.com/traefik/yaegi/interp.genType(0xc0000ff448, 0xc000184c60, {0xc00003a5a0, 0x1d}, 0xc000575540, {0xc0004a6880, 0x2, 0x2}, {0xc0004a6870, 0x2, ...})
	/home/chris/go/pkg/mod/github.com/traefik/yaegi@v0.16.1/interp/type.go:1136 +0xcb
github.com/traefik/yaegi/interp.nodeType2(0xc0000ff448, 0xc000184c60, 0xc000533e00, {0xc0004a6870, 0x1, 0x2})
	/home/chris/go/pkg/mod/github.com/traefik/yaegi@v0.16.1/interp/type.go:898 +0x533f
github.com/traefik/yaegi/interp.nodeType2(0xc0000ff448, 0xc000184c60, 0xc000533cc0, {0xc0006a5320, 0x0, 0x1})
	/home/chris/go/pkg/mod/github.com/traefik/yaegi@v0.16.1/interp/type.go:425 +0x2dda
github.com/traefik/yaegi/interp.nodeType(...)
	/home/chris/go/pkg/mod/github.com/traefik/yaegi@v0.16.1/interp/type.go:400
github.com/traefik/yaegi/interp.(*Interpreter).gta.func1(0xc000533a40)
	/home/chris/go/pkg/mod/github.com/traefik/yaegi@v0.16.1/interp/gta.go:118 +0x1b51
github.com/traefik/yaegi/interp.(*node).Walk(0xc000533a40, 0xc000597c18, 0x0)
	/home/chris/go/pkg/mod/github.com/traefik/yaegi@v0.16.1/interp/interp.go:282 +0x2e
github.com/traefik/yaegi/interp.(*node).Walk(0xc000533900, 0xc000597c18, 0x0)
	/home/chris/go/pkg/mod/github.com/traefik/yaegi@v0.16.1/interp/interp.go:286 +0x6b
github.com/traefik/yaegi/interp.(*node).Walk(0xc000533680, 0xc000597c18, 0x0)
	/home/chris/go/pkg/mod/github.com/traefik/yaegi@v0.16.1/interp/interp.go:286 +0x6b
github.com/traefik/yaegi/interp.(*Interpreter).gta(0xc0000ff448, 0xc000533680, {0xc00048ff08, 0x4}, {0xc00048ff08, 0x4}, {0xc00048ff08, 0x4})
	/home/chris/go/pkg/mod/github.com/trae
fik/yaegi@v0.16.1/interp/gta.go:20 +0x22b
github.com/traefik/yaegi/interp.(*Interpreter).gtaRetry(0xc0000ff448, {0xc000597e00?, 0xc000193860?, 0xc000597d38?}, {0xc00048ff08, 0x4}, {0xc00048ff08, 0x4})
	/home/chris/go/pkg/mod/github.com/traefik/yaegi@v0.16.1/interp/gta.go:395 +0x152
github.com/traefik/yaegi/interp.(*Interpreter).CompileAST(0xc0000ff448, {0x11069e8?, 0xc000193860?})
	/home/chris/go/pkg/mod/github.com/traefik/yaegi@v0.16.1/interp/program.go:92 +0x113
github.com/traefik/yaegi/interp.(*Interpreter).compileSrc(0xc0000ff448, {0xf754e5?, 0x0?}, {0x0?, 0xc00034dd78?}, 0x20?)
	/home/chris/go/pkg/mod/github.com/traefik/yaegi@v0.16.1/interp/program.go:64 +0xaa
github.com/traefik/yaegi/interp.(*Interpreter).eval(0xc0000ff448, {0xf754e5?, 0x0?}, {0x0?, 0x0?}, 0x0?)
	/home/chris/go/pkg/mod/github.com/traefik/yaegi@v0.16.1/interp/interp.go:554 +0x25
github.com/traefik/yaegi/interp.(*Interpreter).Eval(...)
	/home/chris/go/pkg/mod/github.com/traefik/yaegi@v0.16.1/interp/interp.go:496
main.main()
	/home/chris/os_testing/yaegi-test/main.go:21 +0x9d
exit status 2

Yaegi Version

0.16.1

Additional Notes

I have been working on a traefik middleware plugin and recently added the popular github.com/jellydator/ttlcache/v3 package to it. When doing so, my traefik pod would throw yaegi nil reference exceptions when starting up and loading the plugin.

I tried to locally interpret the plugin code with the latest yaegi cli and saw the same result. I then created the sample go program above, and also had the same result there (note that in the sample app, ./src exists with vendored package directory tree inside, to be used as the GOPATH).

The error output doesn't really tell me what went wrong or if there is anything I can do to fix it. I assume that this is some type of bug and should not be occurring.