Bugs item #1225368, was opened at 2005-06-22 08:29 Message generated for change (Settings changed) made by simonpj You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=108032&aid=1225368&group_id=8032
Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: Compiler (Type checker) Group: None >Status: Closed >Resolution: Fixed Priority: 5 Submitted By: Einar Karttunen (ekarttun) Assigned to: Nobody/Anonymous (nobody) Summary: Typechecker loop and stack overflow in 6.4 Initial Comment: The following seems to trigger an loop in the typechecker, which does from stack overflow after a while. The example is quite pointless but shows the bug. newtype PRef a = PRef a type Drop1 a = a class Ref a r | a -> r where readRef :: a -> r instance Ref (PRef a) (Drop1 a) where readRef (PRef v) = v Here is a dump from the test (bug.hs contains the above code): [EMAIL PROTECTED] ~/work/pcl/hpclc $ ghci -v -fglasgow-exts bug.hs ___ ___ _ / _ \ /\ /\/ __(_) / /_\// /_/ / / | | GHC Interactive, version 6.4, for Haskell 98. / /_\/ __ / /___| | http://www.haskell.org/ghc/ \____/\/ /_/\____/|_| Type :? for help. Using package config file: /usr/lib/ghc-6.4/package.conf Using package config file: /home/e/.ghc/i386-linux-6.4/package.conf Hsc static flags: -static *** Parser: *** Desugar: *** Simplify: *** CorePrep: *** ByteCodeGen: Loading package base-1.0 ... linking ... done. *** Parser: *** Desugar: *** Simplify: *** CorePrep: *** ByteCodeGen: *** Chasing dependencies: unload: retaining objs [] unload: retaining bcos [] Stable modules: unload: retaining objs [] unload: retaining bcos [] *** Compiling Main ( bug.hs, interpreted ): compile: input file bug.hs *** Checking old interface for Main: Compiling Main ( bug.hs, interpreted ) *** Parser: *** Renamer/typechecker: *** Exception: stack overflow ---------------------------------------------------------------------- Comment By: Simon Peyton Jones (simonpj) Date: 2005-06-28 09:36 Message: Logged In: YES user_id=50165 Excellent point. Now fixed. tc195.hs tests this case. Thank you for the report ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=108032&aid=1225368&group_id=8032 _______________________________________________ Glasgow-haskell-bugs mailing list [email protected] http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
