Another i386 problem

[Jasper Taylor]

Using Ubuntu Xenial 32-bit which is old enough not to have the issue I 
reported recently, I found that building the current git gprolog 
produces problems with the is/2 predicate, for instance:

 ?- P is 2+9.

P = 2

yes
| ?- P is 8*8*8.

Fatal Error: Segmentation Violation (bad address: (nil))

However, earlier gprolog releases build and run OK, so I did a git 
bisect with the following result: (note that I was building with 
--disable-fd-solver for speed)

4e40b31c2b0527e03d09e2344b43259e626a1b50 is the first bad commit
commit 4e40b31c2b0527e03d09e2344b43259e626a1b50
Author: Daniel Diaz <didou.diaz@gmail.com>
Date:   Wed Mar 22 16:58:50 2023 +0100

    fixes for clang-15 warning (ptr to fct needs arg specified) + 
updates in FD (fd2c, fd_to_c.h)

:040000 040000 ea2364251789b502fc9871217c08383403ed0b0a 
898a248669b5491eaf14e79875451738b206baa3 M    src

Regards Jasper