SPECIALIZE silently fails to apply
There seem to be two problems:
- The active
SPECIALIZEpragma should be applied, but isn't. This can be seen by comparing the core and runtimes of
vtTest(fast). I need this version of the pragma in my real code as the phantom type
mis reified, so I need to specialize the vector code without specifying the phantom type.
- I can get
fcTestto run fast if I use the commented-out
SPECIALIZEpragma instead. However, that pragma seems very straightforward to me (all types are concrete). The docs indicate that GHC should automatically specialize in most cases, why does it not specialize to the commented-out signature automatically?
This problem is also posted here: http://stackoverflow.com/questions/21071706/specialization-with-constraints