Thanks.  Since you didn't answer soon, and since I did get other info
about non-free software needed for OpenSolaris, I already asked for a
correction in the interview.  I made it general so that I won't have
to go into these specifics.  But I would like to know more about the
need for Devpro:

    Not free development environment that is REQUIRED to compile Solaris.

Someone else showed me some text which seems to say that you can
also compile it with GCC.  From http://opensolaris.org/os/downloads/on/:

    You will then need to download the compilers specific to your
    platform . Choose either:

	* The Sun Studio Compilers (Recommended). NOTE: Sun
    Studio 11 is required for building Build 45 and higher....

	-or-

	* The GCC Compiler found in Solaris Express, Community
    Edition build 22 or later. (Please see the gcc tools page for
    more information if choosing this option.) 

However, I don't know precisely what question that is the answer to.
Maybe it doesn't apply to ALL the OpenSolaris software.

Is there text that says that certain components can compile only
with Devpro?