December 2010 - jhc - Haskell.org

foreign ptr bugs
by Korcan Hussein 01 Jan '11

01 Jan '11

Hi I mentioned this briefly in the past before, there is a bug when there are multiple foreign pointers in the same lexical scope obtained from (different) foreign binding functions. The pointer values end up having the same address this typically happens when GCC optimizations are enabled for which most of the time I can make code work correctly by adding -fdebug option to jhc. I've attached some test code which prints out pointer values while trying to blit a loaded image to screen, you'll need to grab my modified version of the SDL Haskell bindings ( darcs get http://patch-tag.com/r/snk_kid/jhc-sdl there is a makefile in jhc folder just make, make install). If you first try building the test code with the command: jhc -p SDL test.hs -o test --optc='-lSDL' and then see the result and output of the program running then try with adding "-fdebug" you should see the difference. Another problem I've been having is erroneous C code generated with the same test code when I set the flag "-fno-global-optimize". I'm using fedora, jhc-0.7.6 The image can be found here: https://github.com/snkkid/LazyFooHaskell/blob/master/lesson01/hello.bmp

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What are these garbage-collectors?
by Robert Clausecker 20 Dec '10

20 Dec '10

Hi guys! Since a while I'm playing around with JHC and wanted to ask something about the garbage collector(s). First, what is this "Boehm" thing? Is it some other garbage collector written by somebody else? I can't run it on my machine. The other thing: When I compile this* program with GC enabled, the output is random crap or it segfaults. What happens here? I should dig into it deeper. Possibly someone can give my some adivise, I guess it's mostly a matter of the arrays or something else. Yours, Robert Clausecker *: The program is available here: https://github.com/fuzxxl/BWInf in the folder Aufgabe4. Make shure to checkout the "performance" branch. I changed some stuff to make it compile with JHC, and reverted it afterwards. Sorry, as this was pure homework for some competition, I coded in German. I can try to translate it, but maybe it's understandable as is. The program calculates the expected result of some game or may play for n times. Given no parameters, it will analyze, with "-n -c ###" it will play n games. On GHC, it will run in constant space and 1000000 games are done in about 6 seconds. JHC is much worse.

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darcs patch: pre-initialize GC caches to avoid check in allocator g...
by John Meacham 12 Dec '10

12 Dec '10

Tue Dec 7 04:17:05 PST 2010 John Meacham <john(a)repetae.net> * pre-initialize GC caches to avoid check in allocator gaining a couple percent in speed.

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darcs patch: don't increment allocation count when we arn't using i...
by John Meacham 12 Dec '10

12 Dec '10

Mon Dec 6 21:03:22 PST 2010 John Meacham <john(a)repetae.net> * don't increment allocation count when we arn't using it for status updates.

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darcs patch: fix bug where the static argument transf... (and 1 more)
by John Meacham 06 Dec '10

06 Dec '10

Mon Dec 6 19:15:57 PST 2010 John Meacham <john(a)repetae.net> * fix bug where the static argument transformation would clear rules. clean up a lot of code. Mon Dec 6 19:33:58 PST 2010 John Meacham <john(a)repetae.net> * remove quadratic behavior in programSetDs'

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darcs patch: fix type checker bug that occasionally r... (and 1 more)
by John Meacham 06 Dec '10

06 Dec '10

Mon Dec 6 04:04:51 PST 2010 John Meacham <john(a)repetae.net> * fix type checker bug that occasionally reported false erros Mon Dec 6 04:25:55 PST 2010 John Meacham <john(a)repetae.net> * clean ups and remove unused module, make selftest work with the new ghc

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darcs patch: fix pretty printing fixity of core to reduce ambiguity
by John Meacham 06 Dec '10

06 Dec '10

Sat Dec 4 15:18:05 PST 2010 John Meacham <john(a)repetae.net> * fix pretty printing fixity of core to reduce ambiguity

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darcs patch: Fix a lot of compiler warnings, clean up dependencies.
by John Meacham 03 Dec '10

03 Dec '10

Fri Dec 3 19:59:31 PST 2010 John Meacham <john(a)repetae.net> * Fix a lot of compiler warnings, clean up dependencies.

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