We have a commercial application that we build on 32-bit CentOS 4.8 (equivalent to Red Hat Enterprise Linux (RHEL) 4 update 8.
The default gcc compiler is at 3.4.6
We are able to run our binary on both 32- and 64-bit CentOS/RHEL 4 and 5 including completely un-updated RHEL 4.
THE QUESTION: If we update to a newer gcc 4 version, will the binary still run on a completely un-updated RHEL 4
The newest gcc appears to be 4.5.1 and 4.4.5
(And yes there are customers who install the intial version, run on an isolated network with no Internet access, and NEVER update from the as-shipped version.)
This issue has arisen because we are now porting to 64-bit FreeBSD 8.1 for amd64 and the default gcc there is gcc 4.2.1