internal compiler error: walkexpr: switch 1 unknown op CALL

[edsrzf]

1. What is a short input program that triggers the error?
package main

var r = f()

func main() {
    r.m()
}

2. What is the full compiler output?
walk [9738f50]
.   CALL l(6) tc(1)
.   .   DOT l(6) tc(1)
.   .   .   NAME-r G0 u(1) a(1) l(3) x(0+0) class(PEXTERN) tc(1) used(1)
.   .   .   NAME-m G0 u(1) a(1) l(6) x(0+0)
test.go:3: undefined: f
test.go:6: internal compiler error: walkexpr: switch 1 unknown op CALL l(6) tc(1)

3. What version of the compiler are you using?  (Run it with the -V flag.)
8g version weekly.2011-06-16 8838+

[griesemer]

Comment 1:

Here's a slightly simpler version with similar crash:
package main
var r = f
func main() {
    r()
}
6g test.go
walk [100850788]
.   CALL l(4) tc(1)
.   .   NAME-r G0 u(1) a(1) l(2) x(0+0) class(PEXTERN) tc(1) used(1)
test.go:2: undefined: f
test.go:4: internal compiler error: walkexpr: switch 1 unknown op CALL l(4) tc(1)

Labels changed: added compilerbug.

Owner changed to @rsc.

Status changed to Accepted.

[gopherbot]

Comment 2 by m@capitanio.org:

I've got a similar bug:
package main
import (
        //"io"
        "bytes"
)
func blahblah(w io.Writer) {
        w.Write([]byte(""))
}
func blah() {
        blahblah(bytes.NewBuffer(nil))
}
func main() {}
walk [7f96a814ec00]
.   CALL l(9) tc(1)
.   .   DOT l(9) tc(1)
.   .   .   NAME-w G139 u(1) a(1) g(139) l(8) x(0+0) class(PPARAM) f(1) tc(1) used(1)
.   .   .   NAME-Write G0 u(1) a(1) l(9) x(0+0)
.   CALL-list
.   .   ARRAYLIT l(9) tc(1) []uint8
.   .   .   LITERAL-I1 u(1) a(1) l(9) ideal
.   .   ARRAYLIT-list
.   .   .   KEY l(9)
.   .   .   .   LITERAL-I0 u(1) a(1) l(9) tc(1) ideal
.   .   .   .   LITERAL-I63 u(1) a(1) l(9) tc(1) uint8
test.go:8: undefined: io
test.go:9: internal compiler error: walkexpr: switch 1 unknown op CALL l(9) tc(1)

[rsc]

Comment 3:

This issue was closed by revision 2f8190a.

Status changed to Fixed.

[lvdlvd]

Comment 4:

Issue #2000 has been merged into this issue.