Re: as for Calc and the math library

[Richard Stallman <rms@gnu.org>]

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  > >No.  What we need is the declaration _by_the_library_ being loaded
  > >that it complies.  It is not an agreement between Emacs and the
  > >library, it's a _requirement_ on our part that only the library itself
  > >can fulfill.

  > I have seen your previous answers to others, and I do understand
  > the point you make, but I think the argument fails because a
  > module can be just a proxy to a non-free library. If I can put it
  > in other words, I wonder if it is a "false sense of security",
  > because it is a guarantee by the person who writes the C module,
  > not the 3rd party library they link to. Of course they are
  > violating the license if they link to a non-free library, but that
  > we are agreeing about we can't prevent.

You're right, and this is a possible problem, but it raises a real
copyleft compliance issue only in a specific kind of occasion: when
someone writes such an intermediary module that loads a nonfree
library, _and distributes that intermediary module_ for such use.

Just writing such an intermediary module and using it oneself does not
raise a copyleft compliance issue, because GPLv3 says one can make any
sort of modificatoin and use it privately -- even actually copying in
nonfree code.  Where the copyleft requirement comes into pkay is for
making a modified version and distributing it to others.

So it could be good to keep an eye on the modules that people are
releasing, to make sure they do not load in other nonfree code.
If they do, the FSF should tell their distributors to stop.

Given this situation, a spcial label as a flag for "this library is
free" might be useful, We just have to remember taht such a flag label
is not proof of anything.  Its presence is only a statement (which can
be false) of intent that the module be entirely GPL3-compatible free
code and that it link in only GPL3-compatible other modules.

-- 
Dr Richard Stallman (https://stallman.org)
Chief GNUisance of the GNU Project (https://gnu.org)
Founder, Free Software Foundation (https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)