The only GNU Prolog version that is known to work with the PPL is a
patched version of the "unstable version" available at

  ftp://ftp.inria.fr/INRIA/Projects/contraintes/gprolog/unstable/gprolog-20040608.tgz

(which unpacks to a directory called `gprolog-1.2.18').
The patch to be applied is given below.

So that it can be used with the GNU Prolog PPL interface (and, for
that matter, with any foreign code), the GNU Prolog installation must
be configured with the `--disable-regs' option.


*** gprolog-1.2.18/src/TopComp/top_comp.c.orig	Fri Jun  4 18:05:02 2004
--- gprolog-1.2.18/src/TopComp/top_comp.c	Sun Jul  3 11:24:36 2005
***************
*** 1085,1091 ****
  	      if (++i >= argc)
  		Fatal_Error("FILE missing after %s option", last_opt);

! 	      cmd_cc.exe_name = argv[i];
  	      continue;
  	    }

--- 1085,1091 ----
  	      if (++i >= argc)
  		Fatal_Error("FILE missing after %s option", last_opt);

! 	      cmd_cc.exe_name = cmd_link.exe_name = argv[i];
  	      continue;
  	    }

