unused-non-trivial-variable

Warns about unused Qt value classes. Compilers usually only warn when trivial classes are unused and don't emit warnings for non-trivial classes.

This check has a whitelist of common Qt classes such as containers, QFont, QUrl, etc and warns for those too.

See UnusedNonTrivialType::isInterestingType(QualType t) for a list of all types.

It's possible to extend the whitelist with user types, by setting the env variable CLAZY_UNUSED_NON_TRIVIAL_VARIABLE_WHITELIST. It accepts a comma separate name of types.

It's possible to disable the whitelist via exporting CLAZY_EXTRA_OPTIONS=unused-non-trivial-variable-no-whitelist, when this env variable is set clazy will warn for any unused non-trivial type. This will create many false positives, such as RAII classes, but still useful to run at least once on your codebase. When disabling the whitelist this way it's also possible to black list types, by setting a comma separated list of types to CLAZY_UNUSED_NON_TRIVIAL_VARIABLE_BLACKLIST