illumos.sh references /opt/SUNWspro, I think that should be /opt/sunstudio12.1/
Updated by Rich Lowe about 11 years ago
Nope. The default compiler is Sun Studio 12 (not 12u1) + patches, 12u1+patches is only used for lint. The current default is correct.
Both stock 12u1, and the 12u1+patches formerly available from opensolaris.org to provide lint have known issues involving ON, which would also apply to illumos.