when one wants to recompile the whole tree with a plugin the easiest way should be to add the necessary -fplugin* switches to CFLAGS. unfortunately setup-allowed-flags strips them away thus i'd like to request $subject. alternatively users should be able to easily extend this whitelist somehow as adding new switches to this list is quite tedious (overlay+forking the eclass).
another issue is that test-flags-PROG in flag-o-matic.eclass will try each flag on its own which will not work for -fplugin-arg* as it's only valid with the corresponding -fplugin=* flag (and the order is important too but at least the test would preserve that much).
I added -fplugin*. Sorry bout the wait, must have missed this one. test-flags only handling one flag at a time is a known thing. It's hard to special case all the flags that only make sense with another.
thanks for the update. i wonder if test-flags could just be taught to not test -fplugin* at all and just add them to flags directly.
