6prof fails with "ptrace waitpid: unexpected new tid"

[nigeltao]

$ env | grep GO
GOARCH=amd64
GOROOT=/home/nigeltao/go
GOOS=linux
$ cat main.go
package main
import "net"
func main() {
    net.Dial("unix", "", "/tmp/.X11-unix/X0")
}
$ 6g main.go && 6l main.6
$ 6prof ./6.out
ptrace waitpid: unexpected new tid 8827 status 0x137f

[robpike]

Comment 1:

this appears to be linux-specific

[robpike]

Comment 2:

The issue seems to be that in wait1(), waitpid returns a tid for a process before the
rest of the library has discovered it.  We have an ugly hack to install the new thread
info in libmach's thread list and try again, but a better approach is probably required.
 The origin of the race remains undiscovered.

[robpike]

Comment 3:

Labels changed: removed compilerbug.

[rsc]

Comment 4:

Status changed to Duplicate.

Merged into issue #251.