casting unsafe.Pointer to *foo

[gopherbot]

by kai.backman2:

repro on both 6g/darwin and 5g:

package main

import (
    "unsafe"
)

func main() {

    // works
    addr := uintptr(0xfffff400)
    _ = (*int)(unsafe.Pointer(addr))

    // fails
    _ = (*int)(unsafe.Pointer(uintptr(0xfffff400)))
}

[rsc]

Comment 1:

added test/bugs/bug246.go

Status changed to Accepted.

[rsc]

Comment 2:

I think we agree that (*int)(unsafe.Pointer(uintptr(0xfffff400))) should work.
It's not clear to me whether making it work is a bug fix or a language change.

Labels changed: added languagechange.

[robpike]

Comment 3:

the spec says
Any pointer or value of type uintptr can be converted into a Pointer and vice versa.
that says to me: not a language change but a bug.

[gopherbot]

Comment 4 by kai.backman2:

fixed labels

Labels changed: removed languagechange.

[gopherbot]

Comment 5 by kai.backman2:

Owner changed to ---.

[rsc]

Comment 6:

Owner changed to r...@golang.org.

Status changed to Fixed.