Eric Blake wrote:
Then you contrast it with AC_CHECK_DECL, which defines
HAVE_FUNC_DECL
to either 0 or 1, but always defines it. If you use #ifdef in those
situations, you lose (you typed 3 more bytes, and you get the wrong result).
Ok.
Just out of curiosity: is there a reason for this behavior of
AC_CHECK_DECLS, which, quoting the manual, is unlike the other
‘AC_CHECK_*S’ macros?
It is a maintenance nightmare to remember which variables are defined as
0 and which are left undefined, and much simpler to blindly use #if than
it is to decide when #ifdef is necessary.
I understand now. Many thanks for your explanations,
Grégoire
