Re: Why conditionally include config.h?

[Bob Friesenhahn]

On Thu, 13 Sep 2012, Kip Warner wrote:

> Why do many autoconfiscated projects bracket inclusion of the generated
> config.h with #if HAVE_CONFIG_H / #endif. Assuming the build
> environment was configured, why shouldn't the source just always
> unconditionally include config.h? I mean if it isn't there, typically
> that means the user didn't configure first which ought to be an error
> anyways, no?

Since subsequent responses are not yet adequate ...

It is not necessary to have a configuration header when Autoconf is 
used.   If a configuration header is not used, then all definitions 
appear on the compiler command line and HAVE_CONFIG_H is not defined.

However, it is a bug for #if HAVE_CONFIG_H to be used in any installed 
header file because it might apply to any package, including some 
other package.

Bob
--
Bob Friesenhahn
address@hidden, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/