Tcl package Thread source code

When the following script is evaluated in a core-8-branch build, threaderror is called twice, once for the "worker" interpreter and once for the "main" interpreter. If the variable name (resvar in this example) is removed, there is only one call to threaderror. In each case there should be only one call to an error handler.

threaderrorcode

package require Thread
 
proc handle_result args {
    puts [list {variable is changed} $args]
}
 
proc threaderror {tid msg} {
    puts [list {thread error} $tid $msg]
}
 
proc main thread {
    thread::send -async $thread {error {an error}} resvar
}
 
 
thread::errorproc threaderror
interp create t1
set thread [thread::create]
 
after 0 [list [namespace which main] $thread]
 
vwait forever