SCREEN incompatibility between ncurses and ncursesw

[Miroslav Lichvar]

Hi,

after upgrading to a recent ncurses version, applications using narrow
libncurses and wide libtinfo started crashing in _nc_init_acs_sp()
when accessing sp->_acs_map.

It seems the problem is caused by the new fields in SCREEN that are
wrapped in USE_NEW_PAIR, which breaks compatibility between the two
definitions used narrow ncurses and wide tinfo.

I tried moving the fields to the end of the structure close to the
WIDEC fields and it seems it fixed the crash. I'm not sure if this is
the best way to fix it.

--- a/ncurses/curses.priv.h
+++ b/ncurses/curses.priv.h
@@ -1137,11 +1137,6 @@ struct screen {
        int             _pair_count;    /* same as COLOR_PAIRS               */
        int             _pair_limit;    /* actual limit of color-pairs       */
 #if NCURSES_EXT_FUNCS
-#if USE_NEW_PAIR
-       void            *_ordered_pairs; /* index used by alloc_pair()       */
-       int             _pairs_used;    /* actual number of color-pairs used */
-       int             _recent_pair;   /* number for most recent free-pair  */
-#endif
        bool            _assumed_color; /* use assumed colors                */
        bool            _default_color; /* use default colors                */
        bool            _has_sgr_39_49; /* has ECMA default color support    */
@@ -1295,6 +1290,11 @@ struct screen {
        /*
         * ncurses/ncursesw are the same up to this point.
         */
+#if NCURSES_EXT_FUNCS && USE_NEW_PAIR
+       void            *_ordered_pairs; /* index used by alloc_pair()       */
+       int             _pairs_used;    /* actual number of color-pairs used */
+       int             _recent_pair;   /* number for most recent free-pair  */
+#endif
 #if USE_WIDEC_SUPPORT
        /* recent versions of 'screen' have partially-working support for
         * UTF-8, but do not permit ACS at the same time (see tty_update.c).


-- 
Miroslav Lichvar