Bug/misfeature with autoloaded TRAPxxx functions

[Bart Schaefer <schaefer@xxxxxxxxxxxxxxxx>]

zagzig% echo $ZSH_VERSION
4.2.0-dev-1
zagzig% print $-
569XZfims
zagzig% autoload TRAPALRM
zagzig% functions
TRAPALRM () {
        # undefined
        builtin autoload -X
}
zagzig% unfunction TRAPALRM
unfunction: no such hash table element: TRAPALRM
zagzig% functions
TRAPALRM () {
        # undefined
        builtin autoload -X
}
zagzig% trap
zagzig% 


It's impossible to delete TRAPALRM without first defining it.  Also, no
attempt to autoload the function is made when the ALRM signal arrives:

zagzig% kill -ALRM $$
zsh: timeout

(The shell has now exited.)