method _start {} {
        global HEAD current_branch remote_url
+       global _last_merged_branch
 
        set name [_rev $this]
        if {$name eq {}} {
        regsub ^refs/heads/ $branch {} branch
        puts $fh "$cmit\t\tbranch '$branch' of $remote"
        close $fh
+       set _last_merged_branch $branch
 
        set cmd [list git]
        lappend cmd merge