- Glasgow-haskell-users

Duplicate instance declarations of a methodless class
by mm 07 Mar '07

07 Mar '07

Hello, I was thinking that it could maybe be useful to allow duplicate instance declarations, if the class has no methods. From my naive point of view, i can not see problems, scince there are no conflicting methods to choose from. But the following program fails to be compiled by ghc-6.6: > {-# OPTIONS -fglasgow-exts -fallow-undecidable-instances #-} > class GT a b > class Succ a b > data Zero > data One > data Two > data Three > instance Succ One Zero > instance Succ Two One > instance Succ Three Two > instance Succ a b => GT a b > instance (Succ a b, GT b c) => GT a c The former two lines lead to: test5.lhs:22:1: Duplicate instance declarations: instance (Succ a b) => GT a b -- Defined at test5.lhs:22:1 instance (Succ a b, GT b c) => GT a c -- Defined at test5.lhs:23:1

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Re : HDirect and GHC-6.6
by Fernand Lacas 06 Mar '07

06 Mar '07

Hi all, It's been a long time since I had the time to work with haskell, but I have some news about HDirect. I now succeed in compiling "ihc.exe" with the typelib support (see my previous posts on the subject), but I had to bypass the packages. That is, the second compilation stage is made using the object files from the "comlib" rather than the "com" package. I understand that it is rather ugly but I still hope that it may be useful to anyone needing COM support with ghc. If anyone is interested in the source files, feel free to ask me. Sincerely yours, sL ___________________________________________________________________________ Nouveau : téléphonez moins cher avec Yahoo! Messenger ! Découvez les tarifs exceptionnels pour appeler la France et l'international. Téléchargez sur http://fr.messenger.yahoo.com

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Code breaks with '-O', any ideas.
by David Brown 06 Mar '07

06 Mar '07

My program 'harchive' <http://www.davidb.org/darcs/harchive/> breaks if compiled with '-O'. Just wondering if anyone has suggestions on how to figure out what might be causing this. Is is possible to build some files with '-O' and others without? I'm not using unsafePerformIO. Thanks, David

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Query information about installed modules user or system only?
by Marc Weber 05 Mar '07

05 Mar '07

Is there a way to ask ghc-pkg to list all availible packages found in the user lib or system lib or lib given by path? If I have read the documentation corretly it says: no. Is there any reason for this restriction? Can I query ghc-pkg to list pgk-config files (user/ system)? mfg Marc

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Building unregisterised for FreeBSD/amd64
by Gregory Wright 02 Mar '07

02 Mar '07

Hi, I'm trying to get ghc-6.6 running on my FreeBSD/amd64 box. It seems as if the build instructions are stale again. When I run $ cd /tmp/ghc-6.6/rts && gmake boot && gmake it falls over in the RTS, as noted in the documentation. But at the next step, when the libraries are built, $ cd ../libraries $ gmake boot && gmake cabal fails to build because it requires HSrts. This aborts the library build leaving me with an incomplete set of libraries. Is there a simple way to tell the build not to make cabal? Best, Greg

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Registering source files along with .hi and .a files?
by Marc Weber 02 Mar '07

02 Mar '07

I see that there is already haddock-interfaces and haddock-html options contained in package descriptions.. Would it make sense to add a hs-source-files option, too? I'm asking because it would be possible to register the source as well together with tag files. The source files could be used by DrIft. They can be used as reference as well (I think many haskell programmers dive into source when looking at some library features ? At least I do) Or is there already an option to register arbitrary files along with a package? Marc Weber

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Problem compiling GHC
by Cristian Perfumo 02 Mar '07

02 Mar '07

Hi all, I'm having a problem when I try to compile GHC. I did it several times before without any problem but I don't know exactly from which moment it started giving me errors. Anyway, I have some clues: 1) I was modifying some STM stuff and I was receiving errors with (I think) out of date information. Then I did "make clean" in "compiler" and in "libraries/base". 2) I don't know if this has to do but some time ago I installed FilePath library and I hadn't executed "make clean" from this moment on. I insist, these two items are only more information but I'm not sure they're related with the error. So, what I did, to be sure that the error had nothing to do with my modification, was to download GHC again and try to build the original version. But I still get the same error (that I paste below this message). Thank you very much in advance for any help. Regards. Cristian Perfumo ------------------------------------------------------------------------ == make boot -r; in /home/cperfumo/ghc/ghc-6.6-original/ghc-6.6/includes ------------------------------------------------------------------------ ../utils/mkdependC/mkdependC -f .depend -- -O -I. -I../rts -- mkDerivedConstants.c ------------------------------------------------------------------------ == make boot -r; in /home/cperfumo/ghc/ghc-6.6-original/ghc-6.6/compat ------------------------------------------------------------------------ ../utils/mkdependC/mkdependC -f .depend -I. -Iinclude -I../includes -- -O -I. -Iinclude -D__GHC_PATCHLEVEL__=0 -I../libraries/base/cbits -I../libraries/base/include -- cbits/directory.c cbits/rawSystem.c cbits/unicode.c /usr/local/bin/ghc -M -optdep-f -optdep.depend -osuf o -optdep--exclude-module=System.Directory.Internals -H16m -O -I. -Iinclude -Rghc-timing -ignore-package Cabal -I../libraries -fglasgow-exts -no-recomp Compat/Directory.hs Compat/RawSystem.hs Compat/Unicode.hs Distribution/Compat/FilePath.hs Distribution/Compat/ReadP.hs Distribution/Compiler.hs Distribution/GetOpt.hs Distribution/InstalledPackageInfo.hs Distribution/License.hs Distribution/Package.hs Distribution/ParseUtils.hs Distribution/Version.hs Language/Haskell/Extension.hs Compat/Directory.hs:42:7: Could not find module `System.Directory': Use -v to see a list of the files searched for. <<ghc: 8676376 bytes, 5 GCs, 84456/84456 avg/max bytes residency (1 samples), 17M in use, 0.00 INIT (0.00 elapsed), 0.01 MUT (0.12 elapsed), 0.00 GC (0.01 elapsed) :ghc>> make[1]: *** [depend] Error 1 make: *** [stage1] Error 1

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Problems with -caf-all
by R Hayes 02 Mar '07

02 Mar '07

I get the following error message when I try to compile with -caf-all. /tmp/ghc583_0/ghc583_0.s:6482:0: FATAL:Symbol _Mainmain_CAF_cc_ccs already defined. My command line looks like this: ghc --make PriceHisto.hs -ljudy -prof -auto-all -caf-all I also tried the following command line and got the same error: ghc --make PriceHisto.hs -ljudy -prof -caf-all Any ideas as to what I'm doing wrong? R Hayes rfhayes<>@</>reillyhayes.com

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Linker error when building GHC HEAD on Mac OS
by Stefan Holdermans 02 Mar '07

02 Mar '07

I'm trying to build GHC HEAD on Mac OS 10.4.8 (PowerPC), but end up with a linker error: ../compiler/stage1/ghc-inplace -o stage2/ghc-6.7.20070228 -H16m -O -package ghc -Istage2 -cpp -fglasgow-exts -fno-generics -Rghc-timing - I. -IcodeGen -InativeGen -Iparser -Rghc-timing -DGHCI -DDEBUGGER - threaded -fforce-recomp stage2/main/Main.o /usr/bin/ld: warning multiple definitions of symbol _UP /usr/lib/gcc/powerpc-apple-darwin8/4.0.1/../../../libreadline.dylib (terminal.so) definition of _UP /usr/lib/gcc/powerpc-apple-darwin8/4.0.1/../../../libncurses.dylib (lib_termcap.o) definition of _UP /usr/bin/ld: warning multiple definitions of symbol _BC /usr/lib/gcc/powerpc-apple-darwin8/4.0.1/../../../libreadline.dylib (terminal.so) definition of _BC /usr/lib/gcc/powerpc-apple-darwin8/4.0.1/../../../libncurses.dylib (lib_termcap.o) definition of _BC /usr/bin/ld: warning multiple definitions of symbol _PC /usr/lib/gcc/powerpc-apple-darwin8/4.0.1/../../../libreadline.dylib (terminal.so) definition of _PC /usr/lib/gcc/powerpc-apple-darwin8/4.0.1/../../../libncurses.dylib (lib_tputs.o) definition of _PC /usr/bin/ld: Undefined symbols: _stg_interp_constr1_entry _stg_interp_constr2_entry _stg_interp_constr3_entry _stg_interp_constr4_entry _stg_interp_constr5_entry _stg_interp_constr6_entry _stg_interp_constr7_entry _stg_interp_constr8_entry collect2: ld returned 1 exit status <<ghc: 19070104 bytes, 4 GCs, 120108/120108 avg/max bytes residency (1 samples), 16M in use, 0.01 INIT (0.00 elapsed), 0.10 MUT (4.20 elapsed), 0.05 GC (0.08 elapsed) :ghc>> make[3]: *** [stage2/ghc-6.7.20070228] Error 1 make[2]: *** [stage2/ghc-6.7.20070228] Error 2 make[1]: *** [stage2] Error 2 make: *** [bootstrap2] Error 2 Anyone any pointers? Cheers, Stefan

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ghc -fasm declared not too shabby
by dons＠cse.unsw.edu.au 01 Mar '07

01 Mar '07

Got some initial nobench numbers for ghc head -fvia-C versus -fasm, on amd64: http://www.cse.unsw.edu.au/~dons/nobench/x86_64/results.html Overall all of nobench, ghc -fasm averages 3% slower. Not too shabby! There's some wider variation on the microbenchmarks in the imaginary class: one case 20% faster, another 30% slower, average 2% slower. On real programs though, 3% slower on average. The big benefit of course, no perl, no gcc and faster compilation times. -- Don

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