pkg/40735: native vs. pkgsrc expat

[joern.clausen%uni-bielefeld.de@localhost]

>Number:         40735
>Category:       pkg
>Synopsis:       native vs. pkgsrc expat
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Feb 24 13:20:00 +0000 2009
>Originator:     Jörn Clausen
>Release:        
>Organization:
University of Bielefeld
>Environment:
SunOS opensolaris 5.11 snv_101b i86pc i386 i86pc

>Description:
On OpenSolaris 11, expat seems to be considered a native package. When X11_TYPE 
is set to "modular" and PREFER_PKGSRC is defined (in the current case it 
contains "zlib"), the definition of PREFER_PKGSRC in mk/defaults/mk.conf 
(containing expat) is overridden. This causes devel/apr0 to fail:

checking for Expat in /usr... no
configure: error: Expat was not found (or recognized) in "/usr"

Installing textproc/expat manually or adding it to PREFER_PKGSRC solves this 
issue.

I am unsure, what the real problem is:

 - The pkgsrc guide allows to define PREFER_PKGSRC, but fails to mention that 
under certain conditions, it already contains some defaults. Maybe it should 
suggest a syntax that appends packages to a possibly already defined list.

 - textproc/expat/builtin.mk checks for the presence of a native expat, which 
then does not satisfy the requirements of devel/apr0. Maybe the test is not 
sufficient?
>How-To-Repeat:

>Fix: