[ghemical-devel] Private configure tokens in public headers

[Jean Bréfort]

Le jeudi 19 octobre 2006 à 22:18 -0400, Daniel Macks a écrit :
> On Thu, Oct 19, 2006 at 10:00:56PM -0400, Daniel Macks wrote:
> > When I #include the public headers for libghemical-2.10, I wind up
> > polluting my namespace with lots of #define tokens that seems like
> > they should be restricted to libghemical's own source-building
> > process. For example, why should "a library that links against
> > libghemical" see:
> > 
> > /* This is the version of libghemical to be built--it is set in the
> >    configure.ac */
> > #define LIBVERSION "2.10"
> > 
> > (from from libghemicalconfig2.h)? It's the library version of
> > libghemical, not of the library being built against it. The token name
> > is generic enough that it's likely to conflict with my own library's
> > tokens. Likewise, all the autoconf tokens at best cause a slew of
> > redefined warnings due to my own config.h also having them.
> > 
> > Executive summary: restrict header things that are used by the
> > libghemical build process to being private to the build process.  For
> > example, have the libghemical sources #include libghemicalconfig2.h
> > directly instead of having libghemicaldefine.h #include it, and don't
> > install the config header publicly.
> 
> On closer examination, slight mis-diagnosis here. The private config
> should not be installed, but a secondary culprit is ghemical-2.01,
> which #includes it as well as its own config header. Ghemical itself
> should just test for [whatever] instead of relying on libghemical's
> conf tests.

That's not a so good idea. If libghemical and ghemical went to be built
in different environments (something might have been updated between the
two builds), ghemical might be broken.
A better solution would be to have to configuration files. One used in
libghemical cpp files and another one to be included from ghemical
(might be libghemical-features.h). See libgoffice for the implementation
of such a solution (Tommi, I volunteer to do the job if you agree).


>  Here's what happens when compiling ghemical:
> 
> g++-3.3 -DHAVE_CONFIG_H -I. -I. -I.   -I/sw/include -I/sw/include/glib-2.0 -I/sw/lib/glib-2.0/include -I/sw/include/pango-1.0 -I/usr/X11R6/include -I/usr/X11R6/include/freetype2 -I/sw/include/gtk-2.0 -I/sw/include/atk-1.0 -I/sw/lib/gtk-2.0/include   -I/sw/include/glib-2.0 -I/sw/lib/glib-2.0/include -I/sw/include/pango-1.0 -I/usr/X11R6/include -I/usr/X11R6/include/freetype2 -I/sw/include/gtk-2.0 -I/sw/include/atk-1.0 -I/sw/lib/gtk-2.0/include -I/sw/include/gtkglext-1.0 -I/sw/lib/gtkglext-1.0/include   -I/sw/include/glib-2.0 -I/sw/lib/glib-2.0/include -I/sw/include/pango-1.0 -I/usr/X11R6/include -I/usr/X11R6/include/freetype2 -I/sw/include/gtk-2.0 -I/sw/include/atk-1.0 -I/sw/lib/gtk-2.0/include -I/sw/include/libxml2 -I/sw/include -I/sw/include/libglade-2.0   -I/sw/include/glib-2.0 -I/sw/lib/glib-2.0/include   -I/sw/include/ghemical    -g -O2 -c -o fileio.o fileio.cpp
> In file included from project.h:14,
>                  from fileio.cpp:10:
> /sw/include/ghemical/libghemicalconfig2.h:88:1: warning: "VERSION" redefined
> In file included from project.h:13,
>                  from fileio.cpp:10:
> ghemicalconfig2.h:103:1: warning: this is the location of the previous definition
> In file included from filetrans.h:14,
>                  from project.h:51,
>                  from fileio.cpp:10:
> ghemicalconfig2.h:103:1: warning: "VERSION" redefined
> In file included from filetrans.h:13,
>                  from project.h:51,
>                  from fileio.cpp:10:
> /sw/include/ghemical/libghemicalconfig2.h:88:1: warning: this is the location of the previous definition
> In file included from /sw/include/ghemical/eng2_qm_mm.h:13,
>                  from fileio.cpp:18:
> /sw/include/ghemical/libghemicalconfig2.h:88:1: warning: "VERSION" redefined
> In file included from filetrans.h:14,
>                  from project.h:51,
>                  from fileio.cpp:10:
> ghemicalconfig2.h:103:1: warning: this is the location of the previous definition
> 
> dan
>