Re: inttypes.h incompatibility with iostream [#5060]

[Paul Eggert]

> Date: Sun, 9 Dec 2001 19:14:18 -0500 (EST)
> From: Keith Bostic <address@hidden>
> 
> Maybe there should be a way to specify the "Default Includes"
> for autoconf.

Do you really need this as a separate feature?  Why not just
pass the includes that you want to the macros that you want?


>       + Use AC_CHECK_TYPE(u_int) to figure out if you need
>         to declare your own local typedef for u_int.

If you're using your own set of includes, you should use something
like this:

  AC_DEFUN([DB_INCLUDES], [[
  #include <stdio.h>
  #include <sys/types.h>
  ...
  ]])
  AC_CHECK_TYPE(u_int, , ..., [DB_INCLUDES])
  AC_CHECK_TYPE(u_long, , ..., [DB_INCLUDES])
  ...

It may seem a little awkward to pass that extra arg, but I worry about
the alternative of changing the default-includes, an operation that
would have possibly-undesirable side effects.



> Further, even were I willing to include the "Default Includes"
> autoconf uses, it's a nasty problem every time I upgrade.  I
> don't have any way to automatically upgrade my program's list
> of includes, so if I use a different version of autoconf, my
> program's list of includes may suddenly differ from autoconf's
> list, and then my program may not build.

Yes, that's a problem.  But it's not too much of a problem in
practice, as I typically have a "system.h" file that includes those
files.

I believe a system.h-generator is on the todo list for Autoconf
somehwere.

> So, there should probably be a macro that dumps out the list
> of include files that autoconf used, so that changing versions
> of autoconf doesn't result in an out-of-date list of includes
> in the program.

Yup, exactly right: that should go into the system.h-generator.
Good analysis.