I suspect this could interact badly with embedded methods too.

For example, the program in https://play.golang.org/p/xeyW_fDeo9 dereferences a nil pointer in an autogenerated method (see #18617), which might result in a panic trace showing no frames.

(And the workaround of using runtime.FuncForPC would not work for the nil-panic case.)

That's a good example. Amusingly, when run on tip we get a larger stack trace because the first attempt doesn't get any frames, so we retry with runtime frames enabled. But that's clearly not ideal. :)

I have some issue latest version.

1.9.2 => called from # 1

devel => called from # 0

▶ tree
.
├── main.go
└── runtimetest
└── init.go

1 directory, 2 files

main.go

package main
import (
	"fmt"
	t "./runtimetest"
)
func main() {
	fmt.Println(t.File)
}

runtimetest/init.go

package runtimetest

import (
	"fmt"
	"runtime"
)

var File string

func init() {

	_, file, no, ok := runtime.Caller(1)
	if ok {
		fmt.Printf("called from %s#%d\n", file, no)
	}
	File = file
}

brew install go

▶ go version
go version go1.9.2 darwin/amd64
▶ go run main.go
called from <autogenerated>#1

brew install --HEAD go

▶ go version
go version devel +0153a4130d Mon Oct 30 19:55:02 2017 +0000 darwin/amd64
▶ go run main.go
called from #0

@s4l1h, what's the issue? init doesn't have a caller, so arguably HEAD is giving the right answer and 1.9 wasn't.

@aclements
I want to get filename with runtime.
if change the caller skip param 1 to 0.
1.8rc3, 1.9.2 and head version work perfect.

runtime.Caller(1) => runtime.Caller(0)

https://github.com/akmyazilim/assetmanager/blob/master/example/modules/t1/init.go#L17

if change the caller skip param 1 to 0.

Right. I'm still unclear on what you were expecting. Using Caller(1) in an init function is definitely depending on an implementation detail that could easily change for any number of reasons. If you want to find out information on the function that calls Caller(), you should use a skip of 0.

Change https://golang.org/cl/76770 mentions this issue: runtime: don't elide wrapper functions that call panic or at TOS