The ticky_ghc flavour, threaded_rts and RTS ticky counters.
As far as I'm aware:
- The stage2 compiler is always built in the threaded way.
- ghc_ticky is supposed to enable all ticky counters in GHC.
- For the RTS ticky counters we need to #define TICKY_TICKY
- #define TICKY_TICKY is incompatible with the threaded RTS
I don't know why ticky is incompatible with the threaded rts (races on entry updates?). But currently when using ghc_ticky the end result is we don't get the RTS ticky counters.
This is both surprising and very unfortunate. There also isn't an easy way to build a non-threaded stage2 ghc using hadrian as far as I can tell to work around this.