autoscan: Advising that AC_FUNC_REALLOC is not The Right Thing (TM)

[Tim Landscheidt]

Hi,

for background, I'm looking at tackling a bug
(<URI:https://sourceforge.net/tracker/?func=detail&aid=1899047&group_id=97492&atid=618177>)
with flex's build system that seems to stem from the use of
AC_FUNC_REALLOC in configure.in without including gnulib's
(or another) implementation.  I believe this can be fixed by
simply omitting AC_FUNC_REALLOC (on the premise that
realloc(p, 0) is never used).

  The macro was originally added to configure.in on the sug-
gestion of autoscan which basically means that in a few
years some well-meaning developer will probably re-run auto-
scan, re-add the macro and the bug will re-appear.

  So is there a way to advise autoscan that it shouldn't
suggest AC_FUNC_REALLOC?  Another (human) solution would of
course be to add appropriate comments to configure.in and
hope that they will be read, but I'd prefer something more
robust.

TIA,
Tim