error in handling download external packages

[Satish Balay]

On Wed, 22 Oct 2008, Barry Smith wrote:

>   I wasn't saying we had to solve this problem, but I do think it
> is a problem.  A users code could easily pick up the wrong include
> for something since we now have hundreds in our arch/include location.

I guess part of the problem is namespace issue [This would be the
primary reason for picking up the wrong include]. In that sense
include/packagename/pkginc.h might be a valid thing. But the package
has to support this internally [as in 'make install' provides
include/pkgname/pkginclude'. And the recommended usage from user code
would be:

#inlcude "package/pkginc.h"

[this model is not in sync with curent PETSc model of supporing both
install in PETSC_DIR-src and 'make install with prefix']. It might be
better to identify the namespace conflicts and ask the packages to fix
the names..

The other kind of conflict is: user installs superlu separately - and
then tries to use PETSc installed with --download-superlu. These 2
versions of superlu will conflict with each other.. The fix in this
case is to not use the duplicate install of superlu anyway...

Satish