I have downloaded gprolog and the newmain Ancestor example. The code compiles and runs, but either generates an error or does not produce the expected results. Loading the newmail.pl file in the gprolog interpreter does work, so I don't think the problem is the .pl file.
The problem seems to be with the Pl_Query_End(PL_RECOVER). I tried changing it to use PL_KEEP_FOR_PROLOG, which runs, but does not give the correct set of solutions.
Has anybody else had this problem? Any recommendations or proposed fixes?
Below, I've provided information regarding the output, versions, source code etc. Any help here is appreciated.