The GPL actually has a clause agaisnt revocation in section 2:
All rights granted under this License are granted for the
term of copyright on the Program, and are irrevocable
provided the stated conditions are met.
Doesn't this make it illegal to distribute GPL software in France under clause 12?
If conditions are imposed on you (whether by court order, agreement or
otherwise) that contradict the conditions of this License, they do not
excuse you from the conditions of this License. If you cannot convey a
covered work so as to satisfy simultaneously your obligations under this
License and any other pertinent obligations, then as a consequence you may
not convey it at all.
Since allowing the licensor to revoke the licence would be an extra condition.
It doesn't make the distribution illegal per-se, but it does make the license invalid and thus the software unlicensed. Same as "public domain" licensing.
I happen to know about this "France problem" because for a while it affected the OCaml distribution (it has now been resolved by some French-specific legal wrangle).
I don't know how this affects the GPL specifically, but you can be pretty sure that if the GPL doesn't contain France-specific French-language legalese to work around it, then it's likely to be revokable whatever the license says. Of course this only affects you if you're in France or have French contributors.
