April 2012 - Glasgow-haskell-users

Installing binary tarball fails on Linux
by Johan Tibell 09 Oct '12

09 Oct '12

Hi, I tried to install the GHC 7.4.1 32-bit binary tarball today and ran into the error below. Are 32-bit GHC's not supported on 64-bit Linuxes? The error: Installing library in /usr/local/lib/ghc-7.4.1/ghc-prim-0.2.0.0 ghc-cabal: Bad interface file: dist-install/build/GHC/Classes.hi magic number mismatch: old/corrupt interface file? (wanted 33214052, got 129742) Full log: $ tar jxf ghc-7.4.1-i386-unknown-linux.tar.bz2 $ cd ghc-7.4.1/ tibell@tibell:ghc-7.4.1$ ./configure --prefix=/usr/local checking for path to top of build tree... /tmp/ghc-7.4.1 Build platform inferred as: i386-unknown-linux Host platform inferred as: i386-unknown-linux Target platform inferred as: i386-unknown-linux GHC build : i386-unknown-linux GHC host : i386-unknown-linux GHC target : i386-unknown-linux checking for perl... /usr/bin/perl checking if your perl works in shell scripts... yes checking for a BSD-compatible install... /usr/bin/install -c checking whether ln -s works... yes checking for gsed... sed checking for gcc... /usr/bin/gcc checking for gcc... /usr/bin/gcc checking whether the C compiler works... yes checking for C compiler default output file name... a.out checking for suffix of executables... checking whether we are cross compiling... no checking for suffix of object files... o checking whether we are using the GNU C compiler... yes checking whether /usr/bin/gcc accepts -g... yes checking for /usr/bin/gcc option to accept ISO C89... none needed checking version of gcc... 4.4.3 checking how to run the C preprocessor... /usr/bin/gcc -E checking whether ld understands --hash-size=31... checking whether ld understands --reduce-memory-overheads... checking for extra options to pass gcc when compiling via C... -fwrapv checking Setting up CFLAGS, LDFLAGS, IGNORE_LINKER_LD_FLAGS and CPPFLAGS... done checking Setting up CONF_CC_OPTS_STAGE0, CONF_GCC_LINKER_OPTS_STAGE0, CONF_LD_LINKER_OPTS_STAGE0 and CONF_CPP_OPTS_STAGE0... done checking Setting up CONF_CC_OPTS_STAGE1, CONF_GCC_LINKER_OPTS_STAGE1, CONF_LD_LINKER_OPTS_STAGE1 and CONF_CPP_OPTS_STAGE1... done checking Setting up CONF_CC_OPTS_STAGE2, CONF_GCC_LINKER_OPTS_STAGE2, CONF_LD_LINKER_OPTS_STAGE2 and CONF_CPP_OPTS_STAGE2... done checking for .subsections_via_symbols... no checking for GNU non-executable stack support... yes checking for grep that handles long lines and -e... /bin/grep checking for egrep... /bin/grep -E checking for ANSI C header files... yes checking for sys/types.h... yes checking for sys/stat.h... yes checking for stdlib.h... yes checking for string.h... yes checking for memory.h... yes checking for strings.h... yes checking for inttypes.h... yes checking for stdint.h... yes checking for unistd.h... yes checking size of void *... 8 checking for ar... /usr/bin/ar checking whether /usr/bin/ar is GNU ar... yes checking for ar arguments... q checking whether ranlib is needed... no configure: creating ./config.status config.status: creating settings config.status: creating mk/config.mk config.status: creating mk/install.mk **************************************************** Configuration done, ready to 'make install' (see README and INSTALL files for more info.) **************************************************** $ sudo make install make -r --no-print-directory -f ghc.mk install BINDIST=YES NO_INCLUDE_DEPS=YES /usr/bin/install -c -m 755 -d "/usr/local/share/man" /usr/bin/install -c -m 755 -d "/usr/local/share/man/man1" /usr/bin/install -c -m 644 docs/man/ghc.1 "/usr/local/share/man/man1" "rm" -f driver/split/dist/ghc-split echo '#!/usr/bin/perl' >> driver/split/dist/ghc-split echo '$TARGETPLATFORM = "i386-unknown-linux";' >> driver/split/dist/ghc-split echo '$TABLES_NEXT_TO_CODE = "YES";' >> driver/split/dist/ghc-split cat driver/split/dist/ghc-split.prl >> driver/split/dist/ghc-split /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1" /usr/bin/install -c -m 755 driver/split/dist/ghc-split "/usr/local/lib/ghc-7.4.1" /usr/bin/install -c -m 755 -d "/usr/local/bin" "rm" -f "/usr/local/bin/ghci-7.4.1" create () { touch "$1" && chmod 755 "$1" ; } && create "/usr/local/bin/ghci-7.4.1" echo '#!/bin/sh' >> "/usr/local/bin/ghci-7.4.1" echo 'exec "/usr/local/bin/ghc-7.4.1" --interactive ${1+"$@"}' >> "/usr/local/bin/ghci-7.4.1" chmod +x "/usr/local/bin/ghci-7.4.1" "rm" -f "/usr/local/bin/ghci" ln -s ghci-7.4.1 "/usr/local/bin/ghci" /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1/include" /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1/include/." && /usr/bin/install -c -m 644 includes/./*.h "/usr/local/lib/ghc-7.4.1/include/./" && /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1/include/rts" && /usr/bin/install -c -m 644 includes/rts/*.h "/usr/local/lib/ghc-7.4.1/include/rts/" && /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1/include/rts/prof" && /usr/bin/install -c -m 644 includes/rts/prof/*.h "/usr/local/lib/ghc-7.4.1/include/rts/prof/" && /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1/include/rts/storage" && /usr/bin/install -c -m 644 includes/rts/storage/*.h "/usr/local/lib/ghc-7.4.1/include/rts/storage/" && /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1/include/stg" && /usr/bin/install -c -m 644 includes/stg/*.h "/usr/local/lib/ghc-7.4.1/include/stg/" && true /usr/bin/install -c -m 644 includes/ghcautoconf.h includes/ghcplatform.h includes/dist-ghcconstants/header/GHCConstants.h includes/dist-derivedconstants/header/DerivedConstants.h "/usr/local/lib/ghc-7.4.1/include/" /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1/include" /usr/bin/install -c -m 644 rts/dist/build/ffi.h rts/dist/build/ffitarget.h "/usr/local/lib/ghc-7.4.1/include/" /usr/bin/install -c -m 755 -d "/usr/local/bin" "rm" -f "/usr/local/bin/haddock-ghc-7.4.1" create () { touch "$1" && chmod 755 "$1" ; } && create "/usr/local/bin/haddock-ghc-7.4.1" echo '#!/bin/sh' >> "/usr/local/bin/haddock-ghc-7.4.1" echo 'exedir="/usr/local/lib/ghc-7.4.1"' >> "/usr/local/bin/haddock-ghc-7.4.1" echo 'exeprog="haddock"' >> "/usr/local/bin/haddock-ghc-7.4.1" echo 'executablename="$exedir/$exeprog"' >> "/usr/local/bin/haddock-ghc-7.4.1" echo 'datadir="/usr/local/share"' >> "/usr/local/bin/haddock-ghc-7.4.1" echo 'bindir="/usr/local/bin"' >> "/usr/local/bin/haddock-ghc-7.4.1" echo 'topdir="/usr/local/lib/ghc-7.4.1"' >> "/usr/local/bin/haddock-ghc-7.4.1" cat utils/haddock/haddock.wrapper >> "/usr/local/bin/haddock-ghc-7.4.1" chmod +x "/usr/local/bin/haddock-ghc-7.4.1" /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1/html/" /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1/html/Classic.theme/" /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1/html/Ocean.std-theme/" /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1/latex/" /usr/bin/install -c -m 644 utils/haddock/html/frames.html "/usr/local/lib/ghc-7.4.1/html/" /usr/bin/install -c -m 644 utils/haddock/html/haddock-util.js "/usr/local/lib/ghc-7.4.1/html/" /usr/bin/install -c -m 644 utils/haddock/html/Classic.theme/haskell_icon.gif "/usr/local/lib/ghc-7.4.1/html/Classic.theme/" /usr/bin/install -c -m 644 utils/haddock/html/Classic.theme/minus.gif "/usr/local/lib/ghc-7.4.1/html/Classic.theme/" /usr/bin/install -c -m 644 utils/haddock/html/Classic.theme/plus.gif "/usr/local/lib/ghc-7.4.1/html/Classic.theme/" /usr/bin/install -c -m 644 utils/haddock/html/Classic.theme/xhaddock.css "/usr/local/lib/ghc-7.4.1/html/Classic.theme/" /usr/bin/install -c -m 644 utils/haddock/html/Ocean.std-theme/hslogo-16.png "/usr/local/lib/ghc-7.4.1/html/Ocean.std-theme/" /usr/bin/install -c -m 644 utils/haddock/html/Ocean.std-theme/minus.gif "/usr/local/lib/ghc-7.4.1/html/Ocean.std-theme/" /usr/bin/install -c -m 644 utils/haddock/html/Ocean.std-theme/ocean.css "/usr/local/lib/ghc-7.4.1/html/Ocean.std-theme/" /usr/bin/install -c -m 644 utils/haddock/html/Ocean.std-theme/plus.gif "/usr/local/lib/ghc-7.4.1/html/Ocean.std-theme/" /usr/bin/install -c -m 644 utils/haddock/html/Ocean.std-theme/synopsis.png "/usr/local/lib/ghc-7.4.1/html/Ocean.std-theme/" /usr/bin/install -c -m 644 utils/haddock/latex/haddock.sty "/usr/local/lib/ghc-7.4.1/latex/" "rm" -f "/usr/local/bin/haddock" ln -s haddock-ghc-7.4.1 "/usr/local/bin/haddock" /usr/bin/install -c -m 755 -d "/usr/local/bin" "rm" -f "/usr/local/bin/hsc2hs" create () { touch "$1" && chmod 755 "$1" ; } && create "/usr/local/bin/hsc2hs" echo '#!/bin/sh' >> "/usr/local/bin/hsc2hs" echo 'exedir="/usr/local/lib/ghc-7.4.1"' >> "/usr/local/bin/hsc2hs" echo 'exeprog="hsc2hs"' >> "/usr/local/bin/hsc2hs" echo 'executablename="$exedir/$exeprog"' >> "/usr/local/bin/hsc2hs" echo 'datadir="/usr/local/share"' >> "/usr/local/bin/hsc2hs" echo 'bindir="/usr/local/bin"' >> "/usr/local/bin/hsc2hs" echo 'topdir="/usr/local/lib/ghc-7.4.1"' >> "/usr/local/bin/hsc2hs" echo 'HSC2HS_EXTRA="--cflag=-fno-stack-protector "' >> "/usr/local/bin/hsc2hs" cat utils/hsc2hs/hsc2hs.wrapper >> "/usr/local/bin/hsc2hs" chmod +x "/usr/local/bin/hsc2hs" /usr/bin/install -c -m 644 utils/hsc2hs/template-hsc.h "/usr/local/lib/ghc-7.4.1" /usr/bin/install -c -m 755 -d "/usr/local/bin" "rm" -f "/usr/local/bin/ghc-pkg-7.4.1" create () { touch "$1" && chmod 755 "$1" ; } && create "/usr/local/bin/ghc-pkg-7.4.1" echo '#!/bin/sh' >> "/usr/local/bin/ghc-pkg-7.4.1" echo 'exedir="/usr/local/lib/ghc-7.4.1"' >> "/usr/local/bin/ghc-pkg-7.4.1" echo 'exeprog="ghc-pkg"' >> "/usr/local/bin/ghc-pkg-7.4.1" echo 'executablename="$exedir/$exeprog"' >> "/usr/local/bin/ghc-pkg-7.4.1" echo 'datadir="/usr/local/share"' >> "/usr/local/bin/ghc-pkg-7.4.1" echo 'bindir="/usr/local/bin"' >> "/usr/local/bin/ghc-pkg-7.4.1" echo 'topdir="/usr/local/lib/ghc-7.4.1"' >> "/usr/local/bin/ghc-pkg-7.4.1" cat utils/ghc-pkg/ghc-pkg.wrapper >> "/usr/local/bin/ghc-pkg-7.4.1" chmod +x "/usr/local/bin/ghc-pkg-7.4.1" /usr/bin/install -c -m 755 -d "/usr/local/bin" "rm" -f "/usr/local/bin/ghc-pkg" ln -s ghc-pkg-7.4.1 "/usr/local/bin/ghc-pkg" /usr/bin/install -c -m 755 -d "/usr/local/bin" "rm" -f "/usr/local/bin/runghc" create () { touch "$1" && chmod 755 "$1" ; } && create "/usr/local/bin/runghc" echo '#!/bin/sh' >> "/usr/local/bin/runghc" echo 'exedir="/usr/local/lib/ghc-7.4.1"' >> "/usr/local/bin/runghc" echo 'exeprog="runghc"' >> "/usr/local/bin/runghc" echo 'executablename="$exedir/$exeprog"' >> "/usr/local/bin/runghc" echo 'datadir="/usr/local/share"' >> "/usr/local/bin/runghc" echo 'bindir="/usr/local/bin"' >> "/usr/local/bin/runghc" echo 'topdir="/usr/local/lib/ghc-7.4.1"' >> "/usr/local/bin/runghc" cat utils/runghc/runghc.wrapper >> "/usr/local/bin/runghc" chmod +x "/usr/local/bin/runghc" "rm" -f "/usr/local/bin/runhaskell" ln -s runghc "/usr/local/bin/runhaskell" /usr/bin/install -c -m 755 -d "/usr/local/bin" "rm" -f "/usr/local/bin/ghc-7.4.1" create () { touch "$1" && chmod 755 "$1" ; } && create "/usr/local/bin/ghc-7.4.1" echo '#!/bin/sh' >> "/usr/local/bin/ghc-7.4.1" echo 'exedir="/usr/local/lib/ghc-7.4.1"' >> "/usr/local/bin/ghc-7.4.1" echo 'exeprog="ghc-stage2"' >> "/usr/local/bin/ghc-7.4.1" echo 'executablename="$exedir/$exeprog"' >> "/usr/local/bin/ghc-7.4.1" echo 'datadir="/usr/local/share"' >> "/usr/local/bin/ghc-7.4.1" echo 'bindir="/usr/local/bin"' >> "/usr/local/bin/ghc-7.4.1" echo 'topdir="/usr/local/lib/ghc-7.4.1"' >> "/usr/local/bin/ghc-7.4.1" echo 'executablename="$exedir/ghc"' >> "/usr/local/bin/ghc-7.4.1" cat ghc/ghc.wrapper >> "/usr/local/bin/ghc-7.4.1" chmod +x "/usr/local/bin/ghc-7.4.1" "rm" -f "/usr/local/bin/ghc" ln -s ghc-7.4.1 "/usr/local/bin/ghc" /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1" for i in driver/ghc-usage.txt driver/ghci-usage.txt rts/dist/build/libHSrts.a rts/dist/build/libHSrts_p.a rts/dist/build/libHSrts-ghc7.4.1.so rts/dist/build/libHSrts_l.a rts/dist/build/libHSrts_debug.a rts/dist/build/libHSrts_thr.a rts/dist/build/libHSrts_thr_debug.a rts/dist/build/libHSrts_thr_l.a rts/dist/build/libHSrts_thr_p.a rts/dist/build/libHSrts_debug-ghc7.4.1.so rts/dist/build/libHSrts_thr-ghc7.4.1.so rts/dist/build/libHSrts_thr_debug-ghc7.4.1.so rts/dist/build/libffi.so rts/dist/build/libffi.so.5 rts/dist/build/libffi.so.5.0.10 settings; do \ case $i in \ *.a) \ /usr/bin/install -c -m 644 $i "/usr/local/lib/ghc-7.4.1"; \ true /usr/local/lib/ghc-7.4.1/`basename $i` ;; \ *.dll) \ /usr/bin/install -c -m 644 -s $i "/usr/local/lib/ghc-7.4.1" ;; \ *.so) \ /usr/bin/install -c -m 755 $i "/usr/local/lib/ghc-7.4.1" ;; \ *.dylib) \ /usr/bin/install -c -m 755 $i "/usr/local/lib/ghc-7.4.1";; \ *) \ /usr/bin/install -c -m 644 $i "/usr/local/lib/ghc-7.4.1"; \ esac; \ done /usr/bin/gcc -E -undef -traditional -P -DINSTALLING -DLIB_DIR='"/usr/local/lib/ghc-7.4.1"' -DINCLUDE_DIR='"/usr/local/lib/ghc-7.4.1/include"' -DPAPI_INCLUDE_DIR="" -DPAPI_LIB_DIR="" -x c -Iincludes rts/package.conf.in -o rts/package.conf.install.raw grep -v '^#pragma GCC' rts/package.conf.install.raw | sed -e 's/""//g' -e 's/:[ ]*,/: /g' >rts/package.conf.install /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1" for i in utils/haddock/dist/build/tmp/haddock utils/hsc2hs/dist-install/build/tmp/hsc2hs utils/ghc-pkg/dist-install/build/tmp/ghc-pkg utils/runghc/dist-install/build/tmp/runghc ghc/stage2/build/tmp/ghc-stage2; do \ /usr/bin/install -c -m 755 $i "/usr/local/lib/ghc-7.4.1"; \ done "mv" "/usr/local/lib/ghc-7.4.1/ghc-stage2" "/usr/local/lib/ghc-7.4.1/ghc" /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1" "rm" -rf "/usr/local/lib/ghc-7.4.1/package.conf.d" /usr/bin/install -c -m 755 -d "/usr/local/lib/ghc-7.4.1/package.conf.d" "/usr/local/lib/ghc-7.4.1/ghc-pkg" --force --global-conf "/usr/local/lib/ghc-7.4.1/package.conf.d" update rts/package.conf.install Reading package info from "rts/package.conf.install" ... done. "utils/ghc-cabal/dist-install/build/tmp/ghc-cabal" install "/usr/local/lib/ghc-7.4.1/ghc" "/usr/local/lib/ghc-7.4.1/ghc-pkg" "strip" "/usr/local/lib/ghc-7.4.1" libraries/ghc-prim dist-install '' '/usr/local' '/usr/local/lib/ghc-7.4.1' '/usr/local/share/doc/ghc/html/libraries' NO Installing library in /usr/local/lib/ghc-7.4.1/ghc-prim-0.2.0.0 ghc-cabal: Bad interface file: dist-install/build/GHC/Classes.hi magic number mismatch: old/corrupt interface file? (wanted 33214052, got 129742) make[1]: *** [install_packages] Error 1 make: *** [install] Error 2 -- Johan

5 8

Type operators in GHC
by Simon Peyton-Jones 19 Sep '12

19 Sep '12

Dear GHC users As part of beefing up the kind system, we plan to implement the "Type operators" proposal for Haskell Prime http://hackage.haskell.org/trac/haskell-prime/wiki/InfixTypeConstructors GHC has had type operators for some kind, so you can say data a :+: b = Left a | Right b but you can only do that for operators which start with ":". As part of the above wiki page you can see the proposal to broaden this to ALL operators, allowing data a + b = Left a | Right b Although this technically inconsistent the value page (as the wiki page discussed), I think the payoff is huge. (And "A foolish consistency is the hobgoblin of little minds", Emerson) This email is (a) to highlight the plan, and (b) to ask about flags. Our preferred approach is to *change* what -XTypeOperators does, to allow type operators that do not start with :. But that will mean that *some* (strange) programs will stop working. The only example I have seen in tc192 of GHC's test suite {-# LANGUAGE TypeOperators #-} comp :: Arrow (~>) => (b~>c, c~>d)~>(b~>d) comp = arr (uncurry (>>>)) Written more conventionally, the signature would look like comp :: Arrow arr => arr (arr b c, arr c d) (arr b d) comp = arr (uncurry (>>>)) or, in infix notation {-# LANGUAGE TypeOperators #-} comp :: Arrow arr => (b `arr` c, c `arr` d) `arr` (b `arr` d) comp = arr (uncurry (>>>)) But tc192 as it stands would become ILLEGAL, because (~>) would be a type *constructor* rather than (as now) a type *variable*. Of course it's easily fixed, as above, but still a breakage is a breakage. It would be possible to have two flags, so as to get - Haskell 98 behaviour - Current TypeOperator behaviuor - New TypeOperator behaviour but it turns out to be Quite Tiresome to do so, and I would much rather not. Can you live with that? http://chrisdone.com/posts/2010-10-07-haskelldb-and-typeoperator-madness.ht…

13 24

recent changes to hsc2hs break wrapping c++
by Evan Laforge 09 Sep '12

09 Sep '12

Recently a change was made to hsc2hs to fix this ticket: http://hackage.haskell.org/trac/ghc/ticket/2897 Unfortunately, the result is I (apparently) can't use it now. Here's how that happens: The change was to remove the dependency on HsFFI.h. However, the solution is to create a little wrapper .c file that includes wrappers around various stdio functions like fputs(). This relies on C allowing implicit casts from void* to e.g. FILE*, and is also happy to let you use undeclared functions. g++ rejects that code. And since I am calling into C++ (via a 'extern "C" { ... }' wrapper) I wind up including C++ headers that contain the structs I want hsc2hs to calculate offsets for. Of course one solution is to use C as hsc2hs expects, but it would be awkward to split my (largish) c++ program's headers into C compatible and C++ only. So meanwhile I've reverted back to an older version of hsc2hs that includes HsFFI.h. Working with c++ headers was maybe not in the original design for hsc2hs, but it's a very useful feature nonetheless. WRT HsFFI.h and the ticket, I added -I(ghc --print-libdir)/include to my hsc2hs rule a long time ago, and it wasn't very hard to do, though I admit it would have been easier had there been documentation about what to do, or a mandatory flag for the HsFFI.h path. It looks like Duncan suggested that already. Or perhaps there's a better way to wrap C++?

3 6

Occasional segfault in GHCi w/ 7.4.1-rc1 and 64bit OS X
by austin seipp 17 Jul '12

17 Jul '12

Hello GHC hackers, I have been trying the recent 7.4.1-rc1 release on my OSX Snow Leopard machine. I am using the 64bit OSX .tar.bz. I used virthualenv/hsenv to set up a virtual environment to test packages with the RC, but I discovered that GHCi seems to segfault somewhat randomly when invoked. I cannot reproduce this problem with 7.0.4 (64bit,) 7.2.2 (64bit,) or 7.5.20111223 (also 64bit.) I have invoked GHCi probably a hundred times each, and have never had it crash. I can crash the RC fairly reliably however. I looked at the shell scripts that invoke GHC and ran GDB with the proper arguments. I got a backtrace like so: $ gdb /Users/a/vh-741-rc1_2/.hsenv/ghc/lib/ghc-7.4.0.20111219/ghc GNU gdb 6.3.50-20050815 (Apple version gdb-1518) (Sat Feb 12 02:52:12 UTC 2011) Copyright 2004 Free Software Foundation, Inc. GDB is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Type "show copying" to see the conditions. There is absolutely no warranty for GDB. Type "show warranty" for details. This GDB was configured as "x86_64-apple-darwin"...Reading symbols for shared libraries .... done warning: Could not find object file "/Users/ian/zz64/ghc-7.4.0.20111219/rts/dist/build/libHSrts_thr.a(ffi64.o)" - no debug information available for "../src/x86/ffi64.c". warning: Could not find object file "/Users/ian/zz64/ghc-7.4.0.20111219/rts/dist/build/libHSrts_thr.a(prep_cif.o)" - no debug information available for "../src/prep_cif.c". warning: Could not find object file "/Users/ian/zz64/ghc-7.4.0.20111219/rts/dist/build/libHSrts_thr.a(types.o)" - no debug information available for "../src/types.c". (gdb) r -B/Users/a/vh-741-rc1_2/.hsenv/ghc/lib/ghc-7.4.0.20111219 --interactive Starting program: /Users/a/vh-741-rc1_2/.hsenv/ghc/lib/ghc-7.4.0.20111219/ghc -B/Users/a/vh-741-rc1_2/.hsenv/ghc/lib/ghc-7.4.0.20111219 --interactive Reading symbols for shared libraries + done GHCi, version 7.4.0.20111219: http://www.haskell.org/ghc/ :? for help Loading package ghc-prim ... linking ... done. Loading package integer-gmp ... linking ... done. Loading package base ... linking ... done. Program received signal EXC_BAD_ACCESS, Could not access memory. Reason: KERN_INVALID_ADDRESS at address: 0x00000000ae21cf68 0x00000001ae2060da in evacuate1 () (gdb) bt #0 0x00000001ae2060da in evacuate1 () #1 0x00000001ae20b868 in scavenge_block1 () Previous frame inner to this frame (gdb could not unwind past this frame) (gdb) So it looks like a GC bug at first glance, but I haven't done rigorous investigation. Again this doesn't happen every time - probably 1/3 the time it crashes, the other 2/3 the time it seems to work fine. This naturally also affects `runghc`. Is this a known issue? Or should I file a bug and investigate further? Perhaps something forgot to get something merged into the 7.4 branch? -- Regards, Austin

7 8

"containing" memory-consuming computations
by Herbert Valerio Riedel 16 Jul '12

16 Jul '12

Hello GHC Devs, One issue that's been bothering me when writing Haskell programs meant to be long-running processes performing computations on external input-data in terms of an event/request-loop (think web-services, SQL-servers, or REPLs), that it is desirable to be able to limit resource-usage and be able to "contain" the effects of computations which exhausts the resource-limits (i.e. w/o crashing and burning the whole process) For the time-dimension, I'm already using functions such as System.Timeout.timeout which I can use to make sure that even a (forced) pure computation doesn't require (significantly) more wall-clock time than I expect it to. But I'm missing a similar facility for constraining the space-dimension. In some other languages such as C, I have (more or less) the ability to check for /local/ out-of-memory conditions (e.g. by checking the return value of e.g. malloc(3) for heap-allocations, or by handling an OOM exception), rollback the computation, and be able to skip to the next computation request (which hopefully requires less memory...) So, is there already any such facility provided by the GHC Platform I've missed so far? ...and if not, would such a memory-limiting facility be reconcilable with the GHC RTS architecture? Cheers, hvr --

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Prelude for type-level programming
by Etienne Laurin 03 Jun '12

03 Jun '12

Hello, To experiment with some of GHC's new features in HEAD, I have started ported part of the Prelude from values and functions to types and constraints. For example: comparing lists. instance Compare '[] '[] EQ instance Compare '[] (x ': xs) LT instance Compare (x ': xs) '[] GT instance (Compare x y o, Case o [ EQ --> Compare xs ys r, o --> o ~ r ]) => Compare (x ': xs) (y ': ys) r Prelude.Type> T :: (Compare '[I 1, I 2] '[I 1, I 3] a) => T a LT Sometimes I get nice error messages. Prelude.Type> T :: If (I 1 == I 2) (a ~ "hello") (a ~ 3) => T a Kind mis-match The left argument of the equality predicate had kind `Symbol', but `3' has kind `Nat' But often GHC refuses to type large constraints when there are too many constraint kinds and free variables. It also gets confused if I pretend to use higher-order kinds. instance ((a >>= Const b) c) => (a >> b) c Kind mis-match The first argument of `>>' should have kind `k0 k1', but `a' has kind `k0 k1' In the instance declaration for `(a >> b) c' I'm not sure yet how this is useful this, but I hope it can at least entertain a few people and stress-test the typechecker. http://code.atnnn.com/projects/type-prelude/repository/entry/Prelude/Type.hs darcs get http://code.atnnn.com/darcs/type-prelude/ Etienne Laurin

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Potential GSoC proposal: Reduce the speed gap between 'ghc -c' and 'ghc --make'
by Mikhail Glushenkov 24 May '12

24 May '12

Hi all, [Hoping it's not too late.] During my work on parallelising 'ghc --make' [1] I encountered a stumbling block: running 'ghc --make' can be often much faster than using separate compile ('ghc -c') and link stages, which means that any parallel build tool built on top of 'ghc -c' will be significantly handicapped [2]. As far as I understand, this is mainly due to the effects of interface file caching - 'ghc --make' only needs to parse and load them once. One potential improvement (suggested by Duncan Coutts [3]) is to produce whole-package interface files and load them in using mmap(). Questions: Would implementing this optimisation be a worthwhile/realistic GSoC project? What are other potential ways to bring 'ghc -c' performance up to par with 'ghc --make'? [1] https://github.com/23Skidoo/ghc-parmake [2] https://gist.github.com/1360470 [3] http://www.reddit.com/r/haskell/comments/qwj5j/the_cabal_of_my_dreams/c41a5… -- () ascii ribbon campaign - against html e-mail /\ www.asciiribbon.org - against proprietary attachments

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trouble building ghc-7.4 on Fedora 18 (devel) ARM
by Jens Petersen 04 May '12

04 May '12

Hi, I have been struggling to build ghc74 on ARM (ideally with llvm3) on Fedora 18 (the current development tree). After applying 4 recent ARM patches from Debian the ghc-7.4.1 build gets to: : "inplace/bin/ghc-stage1" -H32m -O -package-name base-4.5.0.0 -hide-all-packages -i -ilibraries/base/. -ilibraries/base/dist-install/build -ilibraries/base/dist-install/build/autogen -Ilibraries/base/dist-install/build -Ilibraries/base/dist-install/build/autogen -Ilibraries/base/include -optP-DOPTIMISE_INTEGER_GCD_LCM -optP-include -optPlibraries/base/dist-install/build/autogen/cabal_macros.h -package ghc-prim-0.2.0.0 -package integer-gmp-0.4.0.0 -package rts-1.0 -package-name base -XHaskell98 -XCPP -O2 -no-user-package-conf -rtsopts -odir libraries/base/dist-install/build -hidir libraries/base/dist-install/build -stubdir libraries/base/dist-install/build -hisuf hi -osuf o -hcsuf hc -c libraries/base/dist-install/build/GHC/Event/Clock.hs -o libraries/base/dist-install/build/GHC/Event/Clock.o [parallel build line removed] /usr/bin/ld: error: /tmp/ghc5703_0/ghc5703_0.o uses VFP register arguments, libraries/base/dist-install/build/GHC/Event/Clock.o does not /usr/bin/ld: failed to merge target specific data of file /tmp/ghc5703_0/ghc5703_0.o collect2: error: ld returned 1 exit status make[1]: *** [libraries/base/dist-install/build/GHC/Event/Clock.o] Error 1 (full build log at: http://arm.koji.fedoraproject.org/koji/getfile?taskID=723311&name=build.log and more details at http://arm.koji.fedoraproject.org/koji/taskinfo?taskID=723311) I gather that it builds on Debian so I am not quite why it is failing on Fedora. To see if ghc-7.4.2pre is any better I tried building ghc-7.4.1.20120416 too (without any ARM patches), which gets a lot further, to using llvm: "inplace/bin/ghc-stage1" -H32m -O -package-name array-0.4.0.0 -hide-all-packages -i -ilibraries/array/. -ilibraries/array/dist-install/build -ilibraries/array/dist-install/build/autogen -Ilibraries/array/dist-install/build -Ilibraries/array/dist-install/build/autogen -Ilibraries/array/include -optP-include -optPlibraries/array/dist-install/build/autogen/cabal_macros.h -package base-4.5.1.0 -XHaskell98 -XMultiParamTypeClasses -XFlexibleContexts -XFlexibleInstances -XTypeSynonymInstances -XDeriveDataTypeable -XStandaloneDeriving -XRank2Types -XMagicHash -XUnboxedTuples -XForeignFunctionInterface -XUnliftedFFITypes -XCPP -O2 -no-user-package-conf -rtsopts -odir libraries/array/dist-install/build -hidir libraries/array/dist-install/build -stubdir libraries/array/dist-install/build -hisuf hi -osuf o -hcsuf hc -c libraries/array/./Data/Array/IO/Internals.hs -o libraries/array/dist-install/build/Data/Array/IO/Internals.o libraries/array/Data/Array/IO/Internals.hs:2:16: Warning: -#include and INCLUDE pragmas are deprecated: They no longer have any effect Instruction referencing instruction not embedded in a basic block! %ln2ulc = getelementptr inbounds i32* %Sp_Arg, i32 3 %ln2uld = ptrtoint i32* %ln2ulc to i32 Instruction does not dominate all uses! %ln2ulc = getelementptr inbounds i32* %Sp_Arg, i32 3 tail call cc10 void @stg_ap_ppp_fast(i32* %Base_Arg, i32* %ln2ulc, i32* %ln2uk8, i32 %ln2uky, i32 ptrtoint (%templatezmhaskell_LanguageziHaskellziTHziSyntax_zdfDataFunDepzuzddData_closure_struct* @templatezmhaskell_LanguageziHaskellziTHziSyntax_zdfDataFunDepzuzddData_closure to i32), i32 %ln2ul2, i32 %ln2ul6, i32 %SpLim_Arg) nounwind Broken module found, compilation aborted! 0 libLLVM-3.0.so 0x4058f348 1 libLLVM-3.0.so 0x4058f7b4 2 libc.so.6 0x4150a0b0 __default_sa_restorer_v2 + 0 3 libc.so.6 0x41508c7c gsignal + 64 4 libc.so.6 0x4150a2bc abort + 432 5 libLLVM-3.0.so 0x406f88e0 6 libLLVM-3.0.so 0x406e7678 llvm::FPPassManager::runOnFunction(llvm::Function&) + 440 7 libLLVM-3.0.so 0x406e7760 llvm::FPPassManager::runOnModule(llvm::Module&) + 48 8 libLLVM-3.0.so 0x406e733c llvm::MPPassManager::runOnModule(llvm::Module&) + 396 9 libLLVM-3.0.so 0x406e7484 llvm::PassManagerImpl::run(llvm::Module&) + 108 10 opt 0x00014528 main + 2268 11 libc.so.6 0x414f2dd0 __libc_start_main + 272 Stack dump: 0. Program arguments: opt /tmp/ghc22413_0/ghc22413_0.ll -o /tmp/ghc22413_0/ghc22413_0.bc -O2 1. Running pass 'Function Pass Manager' on module '/tmp/ghc22413_0/ghc22413_0.ll'. 2. Running pass 'Module Verifier' on function '@seuH_info' make[1]: *** [libraries/template-haskell/dist-install/build/Language/Haskell/TH/Syntax.o] Error 1 (full log at http://arm.koji.fedoraproject.org/koji/getfile?taskID=746853&name=build.log, more details at http://arm.koji.fedoraproject.org/koji/taskinfo?taskID=746853) I haven't tried HEAD yet though the results at http://darcs.haskell.org/ghcBuilder/builders/kgardas-linux-arm-head/index.h… are not too encouraging. Perhaps I will try building ghc74 on ARM without llvm first, and maybe on Fedora 17 too? Anyway thoughts on how to proceed? Thanks, Jens ps There is actually a proposal to make ARM a Fedora 18 Primary Architecture - though personally I feel it is a bit too early yet - if that happens then this would become a more serious problem, though I know ARM is still not a Tier 1 ghc platform.

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optimizer, spec-constr changes 7.2.2 -> 7.4
by Christian Höner zu Siederdissen 30 Apr '12

30 Apr '12

Hi, I am currently trying to get my ADPfusion library to optimize code using ghc-head (same thing described below happens with 7.4.1). Using ghc-7.2.2, both test programs (Nussinov78 and RNAFold) optimize well, the performance is close to C and ghc-core shows good code. This is mostly to say that optimization using ghc-7.2.2 is not an accident but works reliably. Unfortunately, with ghc-head it seems that constructor specialization does not happen. I see a lot of "case x of, Left -> ..., Right -> ..." and "case x of, Yield -> ..." which leads to really bad (slow) code. As there are some discussions going on regarding the optimizer not optimizing (like the ticks exhausted [1] one), are there other changes in the optimizer that could affect it? spec-constr-count / threshold, simplifier phases, simpl-tick-factor, no-liberate-case I have tried... Thanks, Christian PS: This is a ask-first-try-to-find-a-simple-example-later mail ;-) [1] http://hackage.haskell.org/trac/ghc/ticket/5539

1 0

default instance for IsString
by Greg Weber 25 Apr '12

25 Apr '12

I would like to default IsString to use the Text instance to avoid ambiguous type errors. I see defaulting capability is available for Num. Is there any way to do this for IsString? Thanks, Greg Weber

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