gistfile1.md

panic stacktrace inlined vs not-inlined.

For this code:

package main

var x map[string]string

func add(a, b string) {
	x[a] = b
}

func main() {
	add("foo", "bar")
}

This is the output:

panic: runtime error: assignment to entry in nil map

goroutine 1 [running]:
runtime.panic(0x422a20, 0x45a2dd)
	/home/geertjohan/Applications/go/src/pkg/runtime/panic.c:266 +0xb6
main.main()
	/home/geertjohan/Workspaces/Go/devpath/src/github.com/GeertJohan/ango/bla/stuff.go:10 +0x65

Whereas for this code:

package main

import (
	"fmt"
)

var x map[string]string

func add(a, b string) {
	hello := "hello, world"
	fmt.Println(hello)
	x[a] = b
}

func main() {
	add("foo", "bar")
}

This is the output:

hello, world
panic: runtime error: assignment to entry in nil map

goroutine 1 [running]:
runtime.panic(0x499d00, 0x56679d)
	/home/geertjohan/Applications/go/src/pkg/runtime/panic.c:266 +0xb6
main.add(0x4aeb20, 0x3, 0x4adf80, 0x3)
	/home/geertjohan/Workspaces/Go/devpath/src/github.com/GeertJohan/ango/bla/stuff.go:12 +0xf5
main.main()
	/home/geertjohan/Workspaces/Go/devpath/src/github.com/GeertJohan/ango/bla/stuff.go:16 +0x4b

Note the extra stack frame showing the add function