another sample for the problem in global variable definition

[topxeq]

First thanks to you all. The following program sample.go triggers a panic(maybe related to #730 ):

package main

import "strconv"

var optionsG map[string]string

var roundG int = 30

func strToInt(s string, defaultValue int) int {
	n, err := strconv.ParseInt(s, 10, 0)
	if err != nil {
		return defaultValue
	}

	return int(n)
}

func main() {

	optionsG := map[string]string{"round": "12", "b": "one"}

	roundG = strToInt(optionsG["round"], 50)

	println(roundG)

	println(optionsG)
}

Expected result:

$ go run ./sample.go
12
0xc000039e38

Got:

$ yaegi ./sample.go
sample.go:10:12: panic
sample.go:20:32: panic
reflect.Set: value of type int is not assignable to type map[string]string
goroutine 1 [running]:
runtime/debug.Stack(0x1, 0xc000368600, 0x40)
        c:/go/src/runtime/debug/stack.go:24 +0xa4
github.com/containous/yaegi/interp.(*Interpreter).Eval.func1(0xc00008fde0)
        D:/goprjs/src/github.com/containous/yaegi/interp/interp.go:333 +0xc3
panic(0xce3a40, 0xc00018ce90)
        c:/go/src/runtime/panic.go:969 +0x174
github.com/containous/yaegi/interp.runCfg.func1(0xc0003e40a0, 0xc0003f0100)
        D:/goprjs/src/github.com/containous/yaegi/interp/run.go:115 +0x213
panic(0xce3a40, 0xc00018ce90)
        c:/go/src/runtime/panic.go:969 +0x174
github.com/containous/yaegi/interp.runCfg.func1(0xc0003e4140, 0xc0003ee400)
        D:/goprjs/src/github.com/containous/yaegi/interp/run.go:115 +0x213
panic(0xce3a40, 0xc00018ce90)
        c:/go/src/runtime/panic.go:969 +0x174
reflect.Value.assignTo(0xce2f00, 0xc000402040, 0x182, 0xe1ae4b, 0xb, 0xd29d60, 0x0, 0xc000402050, 0x82, 0xc000402050)
        c:/go/src/reflect/value.go:2403 +0x42d
reflect.Value.Set(0xd29d60, 0xc000190288, 0x195, 0xce2f00, 0xc000402040, 0x182)
        c:/go/src/reflect/value.go:1532 +0xc4
github.com/containous/yaegi/interp._return.func1(0xc0003e4140, 0xc00018cce0)
        D:/goprjs/src/github.com/containous/yaegi/interp/run.go:1792 +0x88
github.com/containous/yaegi/interp.runCfg(0xc0003ee400, 0xc0003e4140)
        D:/goprjs/src/github.com/containous/yaegi/interp/run.go:121 +0x74
github.com/containous/yaegi/interp.call.func7(0xc0003e40a0, 0xc0003e1ab0)
        D:/goprjs/src/github.com/containous/yaegi/interp/run.go:991 +0xc49
github.com/containous/yaegi/interp.runCfg(0xc0003f0100, 0xc0003e40a0)
        D:/goprjs/src/github.com/containous/yaegi/interp/run.go:121 +0x74
github.com/containous/yaegi/interp.(*Interpreter).run(0xc0001b61a0, 0xc0003ef500, 0xc0003e4000)
        D:/goprjs/src/github.com/containous/yaegi/interp/run.go:99 +0x240
github.com/containous/yaegi/interp.(*Interpreter).Eval(0xc0001b61a0, 0xc000364340, 0x19f, 0x0, 0x0, 0x0, 0x0, 0x0)
        D:/goprjs/src/github.com/containous/yaegi/interp/interp.go:409 +0x532
main.main()
        D:/goprjs/src/github.com/containous/yaegi/cmd/yaegi/yaegi.go:159 +0x664