Undocumented Scala 3 compiler options

[Bersier]

Several Scala 3 compiler flags seem to be undocumented.

For example, the only documentation I could find for -Wvalue-discard is on this page, which incorrectly starts with

This doc page is specific to features shipped in Scala 2, which have either been removed in Scala 3 or replaced by an alternative.

Another example is -Wnonunit-statement, which only seems to be unofficially documented in an announcement for Scala 2.13.9...

(Also, there doesn't even seem to be a documentation page for all Scala 3 compiler options.)