| > Deriving costs a lot and we just need someone to figure out what's | > going on. | | are you sure that deriving itself costs a lot? I would expect that | deriving itself is reasonably cheap, but results in a lot of | complicated (e.g. recursive) code that later analyzes have to go | through... I think that's right. But somehow the code generated by 'deriving' tickles some non-linearity (I guess) in the rest of the compiler. It would be great to know what it was. Simon | -----Original Message----- | From: ghc-devs [mailto:ghc-devs-bounces@haskell.org] On Behalf Of | Joachim Breitner | Sent: 30 March 2016 08:11 | To: ghc-devs@haskell.org | Subject: Re: Initial compile time benchmarks | | Hi, | | Am Dienstag, den 29.03.2016, 15:29 -0700 schrieb Edward Z. Yang: | > This ticket may be of interest: | > | > https://ghc.haskell.org/trac/ghc/ticket/9630 | > | > Deriving costs a lot and we just need someone to figure out what's | > going on. | | are you sure that deriving itself costs a lot? I would expect that | deriving itself is reasonably cheap, but results in a lot of | complicated (e.g. recursive) code that later analyzes have to go | through... | | https://na01.safelinks.protection.outlook.com/?url=http%3a%2f%2fghc.has | kell.org%2ftrac%2fghc%2fticket%2f9557&data=01%7c01%7csimonpj%40064d.mgd | .microsoft.com%7c209ce28b44644d1603d408d3586a7ea2%7c72f988bf86f141af91a | b2d7cd011db47%7c1&sdata=7NJ%2fd7z98HtnTvPqQvR5o%2bGr5U6RewWBNlRudH4xZvY | %3d and tickets linked from there are also relevant. In fact, there is | even a keyword for this | meta-issue: | https://ghc.haskell.org/trac/ghc/query?status=!closed&keywords=~derivin | g-perf | | Greetings, | Joachim | | | -- | Joachim “nomeata” Breitner | mail@joachim-breitner.de • | https://na01.safelinks.protection.outlook.com/?url=https%3a%2f%2fwww.jo | achim- | breitner.de%2f&data=01%7c01%7csimonpj%40064d.mgd.microsoft.com%7c209ce2 | 8b44644d1603d408d3586a7ea2%7c72f988bf86f141af91ab2d7cd011db47%7c1&sdata | =bIiW5fIZ9Wnv2IWkDGjTU3PMuA6nmitgcHmBdY5q31Q%3d | XMPP: nomeata@joachim-breitner.de • OpenPGP-Key: 0xF0FBF51F | Debian Developer: nomeata@debian.org