Capture an error in a Go defer function

defer-capture-error.go

import (
	"fmt"
	"io/ioutil"
	"os"
)

func f() (e error) {
	tmpDir, tmpErr := ioutil.TempDir("", "prefix")
	if tmpErr != nil {
		return nil, tmpErr
	}
	defer func() {
		if err := os.RemoveAll(tmpDir); err != nil {
			if e != nil {
				e = fmt.Errorf("%v; %v", e, err)
			} else {
				e = err
			}
		}
	}()
	// ...
	return nil
}