[Python-Dev] Re: HAVE_CONFIG_H

[Guido van Rossum]

> > > I see no references to HAVE_CONFIG_H in the source code (except one
> > > #undef in readline.c), yet we #define it on the command line.  Is that
> > > still necessary?
> 
> > It's autoconf tradition to use that; it would replace DEFS to either
> > many -D options, or -DHAVE_CONFIG_H (if AC_CONFIG_HEADER appears).
> 
> > I don't think we need this, and it can safely be removed.
> 
> The many `-D' options which appear when `AC_CONFIG_HEADER' is not used
> are rather inelegant, they create a lot, really a lot of clumsiness in
> `make' output.  The idea, but you surely know it, was to regroup all
> auto-configured definitions into a single header file, and limit the `-D'
> to the sole `HAVE_CONFIG_H', or almost.  While the:
> 
> #if HAVE_CONFIG_H
> # include <config.h>
> #endif
> 
> idiom, for some widely used sources, was to cope with `AC_CONFIG_HEADER'
> being defined in some projects, and not in others.  There is no need to
> include `config.h', nor to create it, if all `#define's have been already
> done through a litany of `-D' options.

Since we don't use this idiom, we can safely remove the
-DHAVE_CONFIG_H (if we can find where it is set).

--Guido van Rossum (home page: http://www.python.org/~guido/)