[GRASS5] GRASS-header-file locations changed?

[Glynn Clements]

Radim Blazek wrote:

> > > The external packages are using --with-grass only,
> > > not --with-grass-includes/libs.
> >
> > That's a bug.
> 
> Why? GRASS installs everything in GISBASE.
> --with-grass is path to GISBASE.

As a general rule, there's no reason to assume any kind of correlation
between library directories and header directories. The files can
always be moved from their "default" locations, and ultimately you are
going to be defining two different sets of switches in two different
variables.

FWIW, autoconf's built-in AC_PATH_X[TRA] macros produce separate
switches for X:

  --x-includes=DIR        X include files are in DIR
  --x-libraries=DIR       X library files are in DIR

even though the same "optimisation" would have worked on every X
installation I've ever seen (whether /usr/X11R<something>,
/usr/openwin or, with recent versions of X, just /usr).

> > > I still believe that it is a wrong approach to make compilation of
> > > other packages with GRASS support more difficult than it was before.
> >
> > So GRASS' is obliged to install itself according to the demands of
> > third-party packages?
> 
> It breaks compilation for many people. Why we cannot
> support both places untill updated GDAL/QGIS will be available?
> It does not cost anything, until now there were 2 copies of header
> file and it was not problem.

Mostly because I wanted to ensure that GRASS itself wasn't relying
upon multiple copies of the headers. The only practical way to do that
was to ensure that, throughout the compilation process, only one copy
was present, so that anything relying upon additional copies produced
an error.