Re: [PATCH] use m4_require to implement AS_REQUIRE

[Ralf Wildenhues]

* Paolo Bonzini wrote on Sun, Oct 12, 2008 at 07:40:58PM CEST:
> 
> >>   ac_c_check_func() {
> >>     if test $ac_cv...; then
> >>       ...
> >>     else
> >>       ac_c_link_ifelse() {
> >>       }
> >>     fi
> >>   }
> >>
> >> which does not work of course.
> > 
> > For me mere mortal, who doesn't wade in the problems you've studied in
> > detail, what exactly is problematic here?
> 
> Suppose you have:
> 
> ac_c_check_func function_that_is_in_cached
> ... some other test that does uses AC_LINK_IFELSE ...
> 
> ac_c_link_ifelse won't be defined.

I still don't quite understand (but at this point have to admit that I
haven't looked at the implementation _at all_).  If AC_CHECK_FUNC
requires the preparation of AC_LINK_IFELSE, then the latter should be
expanded outside and before the body of the former.  No?

Cheers,
Ralf (and yes, just ignore me unless you have extra time to explain)