Re: Patch: FYI: more doc updates

[Tim Van Holder]

> +With Autoconf 2.13 and earlier, you must explicitly use @code{AC_EXEEXT}
> +to get this support.  With Autoconf 2.50, @code{AC_EXEEXT} is implicit.

In 2.13, I think you could just have AC_EXEEXT, and that would pull in
the compiler checks - with 2.50, AC_EXEEXT is pulled in automatically in
the compiler check (so it only gets run if a compiler is checked).
So, to assist the common-sensically challenged, I'd change the last
sentence to:

 With Autoconf 2.50, @code{AC_EXEEXT} is run automatically if you configure
 a compiler (say, through @code{AC_PROG_CC}).