Minimum gcc version requirements on Linux

Hi,

what is the minimum version of gcc to build Pegasus 2.9.1 on Linux?

The support page

   http://www.openpegasus.org/pp/uploads/40/18363/ReleaseNotes.htm#Supported Platforms

suggests 2.9x, but makes no version statement about Linux on Itanium.

I'm asking this, we because we recently faced exception handling issues
with Pegasus 2.5.4 on Itanium using gcc-2.96. These vanished when
either using a newer gcc, or the old gcc with newer Pegasus 2.9.1.

We are now wondering whether this is considered a defect of
particular Pegasus version 2.5.4, that has been fixed with 2.9.1
also for Itanium? Or whether the latter is coincidence?

In other words: when stretching support for old Linux distributions
as far as possible, but aiming to use the same gcc version across
i386, x86_64, and Itanium, what is the oldest gcc version supported
and recommended?

Thanks a lot for your help!
Cheers!
Michael