Loading "lparallel" hangs

Hello,

  can you provide me some hints for the following problem ?

  I've compiled ecl from git on a debian stretch machine.
  Then I've tried to compile the "qt" example,
    which did hang when loading "lparallel"
  So I started "ecl" from a shell,
  and did execute
    (ql:quickload :lparallel)
  which presents me:
  > To load "lparallel":
  > Load 1 ASDF system:
  >   lparallel
  > ; Loading "lparallel"
  then the process fell silent.
  "top" doesn't show "ecl" to consume cpu cycles.
  Its waiting for something and doesn't proceed.

Regards,
  Robert Larice