racy_2_prints.md

the program

https://go.dev/play/p/x5zlgzvtSYP

package main

var x int = 0

func main() {
	go func() {
		x = 1
	}()
	println(x) // 1
	println(x) // 0
}

I have another question regarding the Go Memory Model.

(1) Can this program print "10", according to the Memory Model?
(2) If that is forbidden, which part of the Go Memory Model excludes such behavior?

https://go.dev/play/p/Fn5I0fjSiKj

package main

var x int = 0

func main() {
	go func() {
		x = 1
	}()
	print(x) // first read: 1
	print(x) // second read: 0
}

I draw a picture of the happens-before relation of this program.
https://gist.github.com/nobishino/8150346c30101e2ca409ed83c6c25add?permalink_comment_id=4388680#gistcomment-4388680

I think the answer to (1) is yes.
Both reads are concurrent with x = 1, so each read can observe both x = 0 and x = 1.
And there is no constraint between the results of the first read and the second read.
So the second read can observe x = 0 even if the first read observes x = 0.

But I'm not sure. Is this understanding correct?