Fix buffer overflow issue in Epics 3.15

["Soltani Farani, Bushra via Tech-talk" <tech-talk at aps.anl.gov>]

Dear Tech-Talk, 

I have a question regarding the buffer overflow issue caused by
_FORTIFY_SOURCE=3 in Ubuntu 24.04.
I have seen that in EPICS 7.0.8.1, this problem was worked around by
redefining _FORTIFY_SOURCE to 2. Then, in EPICS 7.0.9, the flag was reset
to 3, but the issue was fixed in the code.
By comparing the two versions, I see a lot of changes, mostly in .c files,
and I assume most of them are related to fixing the buffer overflow issue.
First, I want to know if I understood this correctly.
Secondly, what is the solution for R3.15.9? Is setting -D_FORTIFY_SOURCE=2
enough? Or will there be a fix for this in a future R3.15.9 release?

Best regards
Bushra