A quick note on the confusion about whether Sun Studio 12 update 1 is a patch-update release of Sun Studio 12 or not.
This particular naming convention has been a source of some major confusion for some customers, so let me come out and say it straight:
"Sun Studio 12 update 1 is NOT a patch update to Sun Studio 12".
They are in fact independent releases (much like Sun Studio 12 and Sun Studio 11 were).
Think of SS12u1 as SS13:
  • Like an independent release, you can install it alongside SS12 in a different partition.
  • Patches made for SS12u1 do NOT apply to SS12
  • Patches made to SS12 have been rolled into SS12u1 as bugfixes, but from the date of SS12u1 release (June 2009) these two maintenance source trees have diverged
  • If an ISV (Oracle apps are included in this) requests a certain patch level for Sun Studio 12 or for Sun Studio 12 update 1, do not assume you can use Sun Studio 12 update 1 instead. You cannot.
  • If an ISV (or other support document) states that "Sun Studio 12 patch xxxxx-nn or higher" is supported or required, do not assume that Sun Studio 12 update 1 will suffice instead, since as you've seen here, those two dont really have anything in common.
This issue gets particularly confusing because Solaris rolls its patches into update releases, so effectively Solaris 10 update 6 (eg) has all the patches created upto a certain cutoff date. Sun Studio does not do this and has never actually produced patch-update releases in the past in this sense.

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