GHC-3.01 can generate some really useful warnings, but some of those
generated by -fwarn-unused-binds (which is switched on via -Wall, too)
are plainly wrong. Silly, but short example:
-- Foo.hs ----------------------
module Foo(Bar(..)) where
data Bar = MkBar
instance Show Bar where
showsPrec _ = baz
baz :: Bar -> ShowS
baz MkBar = showString "MkBar"
-------------------------------
panne@liesl:> ghc -fwarn-unused-binds -c Foo.hs
Foo.hs:9: Warning: `baz' is bound but not used
ghc: module version changed to 1; reason: no old .hi file
GHC doesn't seem to take instance declarations into account when
complaining... :-(
--
Sven Panne Tel.: +49/89/2178-2235
LMU, Institut fuer Informatik FAX : +49/89/2178-2211
LFE Programmier- und Modellierungssprachen Oettingenstr. 67
mailto:[EMAIL PROTECTED] D-80538 Muenchen
http://www.pms.informatik.uni-muenchen.de/mitarbeiter/panne
