Re: AC_CHECK_HEADER

[Paolo Bonzini]

> Well, warnings are to show that something is wrong, and protecting
> includes with #error is right, at least in FreeBSD realm. Perhaps it's
> not a bad idea to use AC_INCLUDE_DEFAULTS or some other mechanism when
> checking a header with preprocessor (at least on FreeBSD).

I think that if the presence check makes no sense for this header, the 
four-argument version with AC_INCLUDES_DEFAULT should be used always.

> OK, now to the patch:
>
> 1. It changes word "preprocessor" for "compiler" in AC_CHECK_HEADER
> comment.

Fine.

> 2. places AC_PREPROC_IFELSE before AC_COMPILE_IFELSE in
> _AC_CHECK_HEADER_MONGREL_BODY

I would like the maintainers of Autoconf to come back from holiday and 
comment on this one.

Paolo