On Fri, Nov 17, 2006 at 05:12:23PM +0000, Simon Peyton-Jones wrote:
The crash is definitely a bug. The user manual does not claim to allow unboxed tuples in the return type for a foreign call; so GHC should reject the program politely.
You might ask "well, couldn't the above program be accepted?". Perhaps so... but why do you want it. You should find that if you say foreign import ccall unsafe getchar :: IO Int and then do { I# x <- getchar; ...} then no boxing occurs. So maybe this new feature isn't reqd. Let us know
okay, I was hoping that ghc would see that I am giving it the unboxed version right out and not try to unbox/rebox things itself. I thought I saw this in the standard libraries, but looking through it again, the cases I was looking at were actually primitives and not foreign imports. so this isn't a bug. I will do the boxing myself, which is fine, it would be nice to run ghc without its optimizer and still not get the superfluous boxing to get a true test of just how our back-ends compare, but for that kind of control perhaps I will need to spit out ghc external core anyway.
| the other is | | where 'global_argc' is a C symbol. | | > foreign import ccall "&global_argc" argc :: Addr#
What's the problem here? Your mail looks garbled.
yes. sorry about that. I started out asking one question, then decided to give some background that led to another one.
Concerning primitive types, Ian will respond in a few days. We're not sure we understand what you want!
At the moment, I don't think I need anything, I was just misreading certain features. the ghc backend seems to be working fine with the following caveats: * all integral types (even Integer) are flattened to Int#. * ghc -O on my generated programs crashes with the following: ghc-6.6: panic! (the 'impossible' happened) (GHC version 6.6 for i386-unknown-linux): primRepHint:VoidRep http://repetae.net/john/computer/jhc/stuff/HelloWorld_code.hs has this behavior when compiled with ghc -O on another note I have gotten these crashes also, but have been unable to recreate them: jhc: internal error: stg_ap_p_ret (GHC version 6.6 for x86_64_unknown_linux) Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug ghc-6.6: panic! (the 'impossible' happened) (GHC version 6.6 for i386-unknown-linux): hptRules FastMutInt [(Atom, False), (Binary, False), (C.FFI, False), (Doc.DocLike, False), (Doc.PPrint, False), (FastMutInt, False), (FrontEnd.SrcLoc, False), (FrontEnd.Tc.Kind, False), (GenUtil, False), (HsSyn, False), (Name.Name, False), (Name.Names, False), (Name.Prim, False), (Name.VConsts, False), (PackedString, False), (Support.CanType, False), (Support.Unparse, False), (Util.VarName, False)] John -- John Meacham - ⑆repetae.net⑆john⑈