Pointers to empty structs behave inconsistently

[lmb]

What version of Go are you using (go version)?

$ go version
go version go1.17 linux/amd64

Reproduced up to 1.14.12.

What did you do?

https://play.golang.org/p/XWirTpyJaDH

	var (
		a = &struct{}{}
		b = &struct{}{}
	)

	fmt.Printf("%p %p %t\n", a, b, a == b)

Prints something like 0x555f30 0x555f30 true. Replacing the Printf with

	fmt.Printf("%p %t\n", a, a == b)

prints 0x555f30 false.

Changing to a non-empty struct like struct { a int } makes the issue go away.

What did you expect to see?

• a != b
• The presence of the Printf should not influence the outcome of a == b

[D1CED]

https://golang.org/ref/spec#Comparison_operators

Pointers to distinct zero-size variables may or may not be equal.

The behavior you are observing while strange is fully compliant with the language specification.