race.slide:

Demo

* Hello

.play race.go

race.go:

package main

import "fmt"

func main() {
    fmt.Println("hello, race")
}

Compile present using Go 1.4, open the demo, and hit Run repeatedly. Result: "hello, race" displays consistently.

Compile present using Go tip, open the demo, and hit Run repeatedly. Result: "hello, race" displays maybe one time in three, although the program claims to have exited successfully.

This is probably a logical race in present or playground that the scheduler changes have exposed.

This is probably a high priority, in that I wouldn't want any GopherCon presenters to do a last minute present upgrade and have any unpleasant discoveries.