Yes, we know about this one. It'll be fixed in the upcoming patch
release.
Thanks for reporting it.
Workaround: expand type synonyms in data type and class decls.
Simon
| -----Original Message-----
| From: Louis Madon [mailto:[EMAIL PROTECTED]]
| Sent: 05 May 2001 01:37
| To: [EMAIL PROTECTED]
| Subject: ghc 5.00 - panic! type def causes <<loop>>
|
|
| The following code snippet duplicates a problem I'm getting
| with the new compiler. Previous versions (ghc 4.08.x) and
| Hugs do not have the problem:
|
|
| module Bug
| where
|
| class CExpr c where
| count :: TEnv c -> Int
|
| data CExpr c => Expr c = Subexpr [Expr c] | Constant Char
|
| data CExpr c => Env c = EnvData c
|
| type TEnv c = Env c
|
|
|
|
| Attempting to compile the above code causes the following error:
|
| ghc-5.00: panic! (the `impossible' happened, GHC version 5.00):
| <<loop>>
|
| Please report it as a compiler bug to
| [EMAIL PROTECTED],
| or http://sourceforge.net/projects/ghc/.
|
|
|
| If I expand out the use of TEnv and just use Env directly the
| problem goes away. For the above example this is no problem,
| but in my real code it would be nice to not have to do this
| as the type has to be expanded out in quite a few places and
| the rhs is much more complex.
|
|
| I'm running ghc 5 on FreeBSD 3.2 with gcc 2.7.2.1
|
| Here's a typescript of the compile session:
|
|
| Script started on Sat May 5 10:14:53 2001
| sh-2.03$ ghc -v -c Bug.hs
| Glasgow Haskell Compiler, Version 5.00, for Haskell 98,
| compiled by GHC version 5.00 Using package config file:
| /usr/local/lib/ghc-5.00/package.conf
| Hsc static
| flags: -static -fignore-interface-pragmas
| -fomit-interface-pragmas -fdo-lamb da-eta-expansion -flet-no-escape
| *** Ineffective C pre-processor
| echo '{-# LINE 1 "Bug.hs" #-}' > /tmp/ghc51808.hspp && cat
| Bug.hs >> /tmp/ghc51808.hspp
|
| *** Checking old interface for hs = Just "Bug.hs", hspp = Just
| "/tmp/ghc51808.hspp":
| Compiling Bug ( Bug.hs, Bug.o )
| *** Parser:
| *** Renamer:
| *** Typechecker:
| Removing: /tmp/ghc51808.s
| Warning: can't remove tmp file /tmp/ghc51808.s
| Removing: /tmp/ghc51808.hspp
| ghc-5.00: panic! (the `impossible' happened, GHC version
| 5.00): <<loop>>
|
| Please report it as a compiler bug to
| [EMAIL PROTECTED], or
| http://sourceforge.net/projects/ghc/.
|
| sh-2.03$ exit
| exit
|
|
| Script done on Sat May 5 10:15:08 2001
|
|
|
| _______________________________________________
| Glasgow-haskell-bugs mailing list
| [EMAIL PROTECTED]
| http://www.haskell.org/mailman/listinfo/glasgow-| haskell-bugs
|
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