[gnugo-devel] unsigned bug in semeai code

[Arend Bayer]

This seems to be a serious bug in do_owl_analyze_semeai to me:

    /* FIXME: This is kind of quick and dirty. */
    probable_eyes_a.b -= matches_found;

proable_eyes_a.b is an unsigned char.

(Haven't checked the effects of fixing this yet.)

Curiously, this is also almost the only time that the struct eyevalue is
directly accessed outside the helper functions in optics.c designed to
do this (set_eyevalue() and friends).
But unfortunately letting struct eyevalue be an incomplete (only
pre-declared type) for owl.c (to make such bugs impossible) is a little
too drastic.

Arend