[plorkyeran]

There are no old warnings because the commits introducing them would have been rejected. Obviously a prerequisite of this is that you get your codebase to the point where it has no warnings. It is sort of like asking how the build server should differentiate between new test failures and existing test failures.

[Am4TIfIsER0ppos]

You update the compiler and suddenly the same code now generates warnings. Are these old warnings or new warnings? I have seen that with printing an integer in a loop 0..99. Old compilers didn't understand the limit so warned that my buffer was not big enough. Middle aged compilers were silent because I assume they understood the range. New compilers started warning again that the range was -2147483648..99 dumb shits.

Or are you one of those to never update a working system, which I completely agree with.

[plorkyeran]

You should test new compiler versions before updating your CI setup. If you get new warnings, you fix them before deploying.