Accessing a nil *big.Float after v8 is initialized segfaults

[konradreiche]

Accessing a nil *big.Float will cause a segfault after v8 has been initialized.

Minimum Example

// main.go
package main

import (
	"fmt"

	"github.com/augustoroman/v8"
	"github.com/konradreiche/v8/crash"
)

func main() {
        var f *big.Float
	fmt.Println(f)
	_ = v8.NewIsolate().NewContext()
        fmt.Println(f)
}

What did I expect?

<nil>
<nil>

What am I seeing instead?

<nil>
Received signal 11 SEGV_MAPERR 000000000000

==== C stack trace ===============================

 [0x000000d24234]
 [0x7fa5afb8ddd0]
 [0x0000004a32a7]
[end of stack trace]
signal: segmentation fault

[konradreiche]

This seems to happen with any type from Go's big package. I traced the problem to the Go formatter code. Somehow, after initializing the v8, the formatter doesn't detect these fields nil types anymore but instead calls the String() method on that nil pointer.

[konradreiche]

Before v8 is initialized this code from the Go stdlib is run: https://golang.org/src/fmt/print.go#L530
After, this code is not reached anymore and the segfault happens. Somehow the recover/panic mechanism doesn't work with V8 being initialized.