Hi, I found that some performance tests cases fail in some setting, and not in another, and after a while I found the cause: The default settings (i.e. no mk/build.mk) have GhcLibHcOpts=-O2, while most development profiles (e.g. devel2) _and the validate settings_ have GhcLibHcOpts=-O1. It doesn’t make a lot of sense to have performance tests cases without fixing this parameter. And I think we really should be validating the settings that we actually used in the final build that we release. Hence three questions: 1. Are the default settings really the settings used when producing the final build? 2. Do we want to use GhcLibHcOpts=-O2 or GhcLibHcOpts=-O for releases? 3. Once 2. is answered, may I change the validate settings to that value, and update the performance tests to expect the number produced with that value? (This was first observed in https://ghc.haskell.org/trac/ghc/ticket/9315#comment:5 but I wanted to the wider audience of the mailing list for such a design decision.) Thanks, Joachim -- Joachim Breitner e-Mail: mail@joachim-breitner.de Homepage: http://www.joachim-breitner.de Jabber-ID: nomeata@joachim-breitner.de