Comment 1 for bug 609803

In MariaDB, we maintain a file support-files/compiler_warnings.supp. This file
is similar to mysql-test/valgrind.supp, it is a list of compiler warnings to
ignore.

This is a compromise between on the one hand eliminating all warnings (so new
ones are easy to spot), and on the other hand not unnecessarily convoluting
the code in cases where a compiler produces a false warning that requires
unnatural code rewrite to eliminate.

The Buildbot setup parses this .supp file to eliminate warnings to be
suppressed. There is a script support-files/ccfilter which can be used to do
similar warning suppressions in a local build.

As far as I can see, the mentioned warnings are already suppressed, and
Buildbot seems to have no non-suppressed compiler warnings on non-windows
platforms.

Of course, it might be that some warnings are needlessly (or wrongly)
suppressed, and such should be fixed; however, I took this bug report to be
simply that we do not have zero warnings. For zero warnings in MariaDB,
currently the policy is that this requires using the compiler_warnings.supp
file.

(Note that the latest MariaDB 5.1 release is 5.1.47).