#3273: memory leak due to optimisation
-----------------------------+----------------------------------------------
Reporter: sebf | Owner:
Type: bug | Status: new
Priority: normal | Component: Compiler
Version: 6.10.1 | Severity: normal
Keywords: | Testcase:
Os: Unknown/Multiple | Architecture: Unknown/Multiple
-----------------------------+----------------------------------------------
Short summary:
The attached programs use lots of space when compiled with -O and run in
constant space without -O.
condensed.hs runs in constant space with -O too, if you remove any
occurrence of 'id'.
original.hs uses a lot of space without -O too, if an alternative
definition of 'iterDepth' is used (see comment there).
I could reproduce this behaviour with ghc-6.8.2 under Linux as well as
ghc-6.10.1 and ghc-6.11.20090331 under Mac OS X 10.5.7.
Full description:
This ticket has an attached tar file with two source files -- original.hs
and condensed.hs -- that can be compiled with and without -O to reproduce
the bug:
{{{
$ ghc -fforce-recomp --make original
[1 of 1] Compiling Main ( original.hs, original.o )
Linking original ...
$ ./original
^C <constant space usage>
$ ghc -v -dcore-lint -O -fforce-recomp --make original
Glasgow Haskell Compiler, Version 6.10.1, for Haskell 98, stage 2 booted
by GHC version 6.8.3
Using package config file:
/Library/Frameworks/GHC.framework/Versions/610/usr/lib/ghc-6.10.1/./package.conf
Using package config file:
/Users/sebf/.ghc/i386-darwin-6.10.1/package.conf
hiding package HTTP-3001.1.3 to avoid conflict with later version
HTTP-3001.1.4
hiding package haddock-2.3.0 to avoid conflict with later version
haddock-2.4.1
hiding package base-3.0.3.0 to avoid conflict with later version
base-4.0.0.0
hiding package old-time-1.0.0.1 to avoid conflict with later version old-
time-1.0.0.2
hiding package filepath-1.1.0.1 to avoid conflict with later version
filepath-1.1.0.2
hiding package process-1.0.1.0 to avoid conflict with later version
process-1.0.1.1
hiding package Cabal-1.6.0.1 to avoid conflict with later version
Cabal-1.6.0.2
hiding package regex-base-0.72.0.2 to avoid conflict with later version
regex-base-0.93.1
hiding package regex-posix-0.72.0.3 to avoid conflict with later version
regex-posix-0.93.2
hiding package regex-compat-0.71.0.1 to avoid conflict with later version
regex-compat-0.92
hiding package network-2.2.0.1 to avoid conflict with later version
network-2.2.1.2
hiding package QuickCheck-1.2.0.0 to avoid conflict with later version
QuickCheck-2.1.0.1
hiding package time-1.1.2.2 to avoid conflict with later version
time-1.1.2.3
hiding package zlib-0.4.0.4 to avoid conflict with later version
zlib-0.5.0.0
hiding package HTTP-3001.1.4 to avoid conflict with later version
HTTP-3001.1.5
hiding package regex-posix-0.93.2 to avoid conflict with later version
regex-posix-0.94.1
hiding package utf8-string-0.3.3 to avoid conflict with later version
utf8-string-0.3.4
hiding package binary-0.4.3.1 to avoid conflict with later version
binary-0.4.4
hiding package zip-archive-0.1.1.1 to avoid conflict with later version
zip-archive-0.1.1.3
hiding package binary-0.4.4 to avoid conflict with later version
binary-0.5
hiding package haddock-2.4.1 to avoid conflict with later version
haddock-2.4.2
hiding package HTTP-3001.1.5 to avoid conflict with later version
HTTP-4000.0.0
hiding package hscolour-1.10.1 to avoid conflict with later version
hscolour-1.11
hiding package HTTP-4000.0.0 to avoid conflict with later version
HTTP-4000.0.1
hiding package haskell-src-exts-0.4.6 to avoid conflict with later version
haskell-src-exts-0.4.8
hiding package HTTP-4000.0.1 to avoid conflict with later version
HTTP-4000.0.4
hiding package digest-0.0.0.1 to avoid conflict with later version
digest-0.0.0.2
hiding package level-monad-0.2.1 to avoid conflict with later version
level-monad-0.3
hiding package HTTP-4000.0.4 to avoid conflict with later version
HTTP-4000.0.7
hiding package digest-0.0.0.2 to avoid conflict with later version
digest-0.0.0.4
hiding package terminfo-0.2.2.1 to avoid conflict with later version
terminfo-0.3.0.2
hiding package stream-monad-0.1 to avoid conflict with later version
stream-monad-0.1.1.0
hiding package tree-monad-0.1 to avoid conflict with later version tree-
monad-0.1.1
hiding package parallel-tree-search-0.2.1 to avoid conflict with later
version parallel-tree-search-0.4
hiding package explicit-sharing-0.2 to avoid conflict with later version
explicit-sharing-0.3.1.1
hiding package tree-monad-0.1.1 to avoid conflict with later version tree-
monad-0.2
hiding package tree-monad-0.2 to avoid conflict with later version tree-
monad-0.2.1
hiding package parallel-tree-search-0.4 to avoid conflict with later
version parallel-tree-search-0.4.1
hiding package level-monad-0.3 to avoid conflict with later version level-
monad-0.3.1
hiding package explicit-sharing-0.3.1.1 to avoid conflict with later
version explicit-sharing-0.3.1.2
hiding package explicit-sharing-0.3.1.2 to avoid conflict with later
version explicit-sharing-0.3.1.3
hiding package explicit-sharing-0.3.1.3 to avoid conflict with later
version explicit-sharing-0.4.0
hiding package explicit-sharing-0.4.0 to avoid conflict with later version
explicit-sharing-0.5.0
wired-in package ghc-prim mapped to ghc-prim-0.1.0.0
wired-in package integer mapped to integer-0.1.0.0
wired-in package base mapped to base-4.0.0.0
wired-in package rts mapped to rts-1.0
wired-in package haskell98 mapped to haskell98-1.0.1.0
wired-in package syb mapped to syb-0.1.0.0
wired-in package template-haskell mapped to template-haskell-2.3.0.0
wired-in package dph-seq mapped to dph-seq-0.3
wired-in package dph-par mapped to dph-par-0.3
Hsc static flags: -static
*** Chasing dependencies:
Chasing modules from: *original.hs
Stable obj: [Main]
Stable BCO: []
Ready for upsweep
[NONREC
ModSummary {
ms_hs_date = Thu Jun 4 13:23:20 CEST 2009
ms_mod = main:Main,
ms_imps = [Control.Monad.Cont]
ms_srcimps = []
}]
compile: input file original.hs
Created temporary directory:
/var/folders/uZ/uZjvUnuPHNmMwDWLlrsGT++++TI/-Tmp-//ghc13029_0
*** Checking old interface for main:Main:
[1 of 1] Compiling Main ( original.hs, original.o )
*** Parser:
*** Renamer/typechecker:
*** Desugar:
Result size = 753
*** Core Linted result of Desugar:
*** Simplify:
Result size = 290
*** Core Linted result of Simplifier phase gentle, iteration 1 out of 4:
Result size = 280
*** Core Linted result of Simplifier phase gentle, iteration 2 out of 4:
Result size = 280
*** Core Linted result of Simplify phase gentle done:
*** Specialise:
Result size = 331
*** Core Linted result of Specialise:
*** Float out (not lambdas, not constants):
Result size = 351
*** Core Linted result of Float out (not lambdas, not constants):
*** Float inwards:
Result size = 351
*** Core Linted result of Float inwards:
*** Simplify:
Result size = 587
*** Core Linted result of Simplifier phase 2 [main], iteration 1 out of 4:
Result size = 390
*** Core Linted result of Simplifier phase 2 [main], iteration 2 out of 4:
Result size = 304
*** Core Linted result of Simplify phase 2 [main] done:
*** Simplify:
Result size = 287
*** Core Linted result of Simplifier phase 1 [main], iteration 1 out of 4:
Result size = 287
*** Core Linted result of Simplify phase 1 [main] done:
*** Simplify:
Result size = 330
*** Core Linted result of Simplifier phase 0 [main], iteration 1 out of 4:
Result size = 310
*** Core Linted result of Simplifier phase 0 [main], iteration 2 out of 4:
Result size = 304
*** Core Linted result of Simplifier phase 0 [main], iteration 3 out of 4:
Result size = 304
*** Core Linted result of Simplify phase 0 [main] done:
*** Demand analysis:
Result size = 304
*** Core Linted result of Demand analysis:
*** Worker Wrapper binds:
Result size = 330
*** Core Linted result of Worker Wrapper binds:
*** GlomBinds:
*** Simplify:
Result size = 345
*** Core Linted result of Simplifier phase 0 [post-worker-wrapper],
iteration 1 out of 4:
Result size = 345
*** Core Linted result of Simplify phase 0 [post-worker-wrapper] done:
*** Float out (not lambdas, constants):
Result size = 353
*** Core Linted result of Float out (not lambdas, constants):
*** Common sub-expression:
Result size = 352
*** Core Linted result of Common sub-expression:
*** Float inwards:
Result size = 352
*** Core Linted result of Float inwards:
*** Simplify:
Result size = 353
*** Core Linted result of Simplifier phase 0 [final], iteration 1 out of
4:
Result size = 353
*** Core Linted result of Simplify phase 0 [final] done:
*** Tidy Core:
Result size = 353
*** Core Linted result of Tidy Core:
writeBinIface: 49 Names
writeBinIface: 98 dict entries
*** CorePrep:
Result size = 430
*** Core Linted result of CorePrep:
*** Stg2Stg:
*** CodeGen:
*** CodeOutput:
*** Assembler:
gcc -I. -c
/var/folders/uZ/uZjvUnuPHNmMwDWLlrsGT++++TI/-Tmp-//ghc13029_0/ghc13029_0.s
-o original.o
*** Deleting temp files:
Deleting:
/var/folders/uZ/uZjvUnuPHNmMwDWLlrsGT++++TI/-Tmp-//ghc13029_0/ghc13029_0.s
Upsweep completely successful.
*** Deleting temp files:
Deleting:
link: linkables are ...
LinkableM (Thu Jun 4 13:55:23 CEST 2009) main:Main
[DotO original.o]
Linking original ...
*** Linker:
gcc -v -o original -DDONT_WANT_WIN32_DLL_SUPPORT original.o
-L/Library/Frameworks/GHC.framework
/Versions/610/usr/lib/ghc-6.10.1/mtl-1.1.0.2
-L/Library/Frameworks/GHC.framework/Versions/610/usr
/lib/ghc-6.10.1/base-4.0.0.0
-L/Library/Frameworks/GHC.framework/Versions/610/usr/lib/ghc-6.10.1/
integer-0.1.0.0
-L/Library/Frameworks/GHC.framework/Versions/610/usr/lib/ghc-6.10.1/ghc-
prim-0.1.0.0
-L/Library/Frameworks/GHC.framework/Versions/610/usr/lib/ghc-6.10.1
-lHSmtl-1.1.0.2 -lHSbase-4.0.0.0
-lHSinteger-0.1.0.0 -lHSghc-prim-0.1.0.0 -lHSrts -lm -lffi -lgmp -ldl -u
_ghczmprim_GHCziTypes_Izh_static_info
-u _ghczmprim_GHCziTypes_Czh_static_info -u
_ghczmprim_GHCziTypes_Fzh_static_info
-u _ghczmprim_GHCziTypes_Dzh_static_info -u _base_GHCziPtr_Ptr_static_info
-u _base_GHCziWord_Wzh_static_info
-u _base_GHCziInt_I8zh_static_info -u _base_GHCziInt_I16zh_static_info -u
_base_GHCziInt_I32zh_static_info
-u _base_GHCziInt_I64zh_static_info -u _base_GHCziWord_W8zh_static_info
-u _base_GHCziWord_W16zh_static_info
-u _base_GHCziWord_W32zh_static_info -u _base_GHCziWord_W64zh_static_info
-u _base_GHCziStable_StablePtr_static_info
-u _ghczmprim_GHCziTypes_Izh_con_info -u
_ghczmprim_GHCziTypes_Czh_con_info -u _ghczmprim_GHCziTypes_Fzh_con_info
-u _ghczmprim_GHCziTypes_Dzh_con_info -u _base_GHCziPtr_Ptr_con_info -u
_base_GHCziPtr_FunPtr_con_info
-u _base_GHCziStable_StablePtr_con_info -u
_ghczmprim_GHCziBool_False_closure -u _ghczmprim_GHCziBool_True_closure
-u _base_GHCziPack_unpackCString_closure -u
_base_GHCziIOBase_stackOverflow_closure
-u _base_GHCziIOBase_heapOverflow_closure -u
_base_ControlziExceptionziBase_nonTermination_closure
-u _base_GHCziIOBase_blockedOnDeadMVar_closure -u
_base_GHCziIOBase_blockedIndefinitely_closure
-u _base_ControlziExceptionziBase_nestedAtomically_closure -u
_base_GHCziWeak_runFinalizzerBatch_closure
-u _base_GHCziTopHandler_runIO_closure -u
_base_GHCziTopHandler_runNonIO_closure
-u _base_GHCziConc_ensureIOManagerIsRunning_closure
-Wl,-search_paths_first
Using built-in specs.
Target: i686-apple-darwin9
Configured with: /var/tmp/gcc/gcc-5488~2/src/configure --disable-checking
-enable-werror --prefix=/usr
--mandir=/share/man --enable-languages=c,objc,c++,obj-c++ --program-
transform-name=/^[cg][^.-]*$/s/$/-4.0/
--with-gxx-include-dir=/include/c++/4.0.0 --with-slibdir=/usr/lib
--build=i686-apple-darwin9 --with-arch=apple
--with-tune=generic --host=i686-apple-darwin9 --target=i686-apple-darwin9
Thread model: posix
gcc version 4.0.1 (Apple Inc. build 5488)
/usr/libexec/gcc/i686-apple-darwin9/4.0.1/collect2 -dynamic -arch i386
-macosx_version_min 10.5.7
-weak_reference_mismatches non-weak -u
_ghczmprim_GHCziTypes_Izh_static_info
-u _ghczmprim_GHCziTypes_Czh_static_info -u
_ghczmprim_GHCziTypes_Fzh_static_info
-u _ghczmprim_GHCziTypes_Dzh_static_info -u
_base_GHCziPtr_Ptr_static_info -u _base_GHCziWord_Wzh_static_info
-u _base_GHCziInt_I8zh_static_info -u _base_GHCziInt_I16zh_static_info -u
_base_GHCziInt_I32zh_static_info
-u _base_GHCziInt_I64zh_static_info -u _base_GHCziWord_W8zh_static_info
-u _base_GHCziWord_W16zh_static_info
-u _base_GHCziWord_W32zh_static_info -u _base_GHCziWord_W64zh_static_info
-u _base_GHCziStable_StablePtr_static_info
-u _ghczmprim_GHCziTypes_Izh_con_info -u
_ghczmprim_GHCziTypes_Czh_con_info -u _ghczmprim_GHCziTypes_Fzh_con_info
-u _ghczmprim_GHCziTypes_Dzh_con_info -u _base_GHCziPtr_Ptr_con_info -u
_base_GHCziPtr_FunPtr_con_info
-u _base_GHCziStable_StablePtr_con_info -u
_ghczmprim_GHCziBool_False_closure -u _ghczmprim_GHCziBool_True_closure
-u _base_GHCziPack_unpackCString_closure -u
_base_GHCziIOBase_stackOverflow_closure
-u _base_GHCziIOBase_heapOverflow_closure -u
_base_ControlziExceptionziBase_nonTermination_closure
-u _base_GHCziIOBase_blockedOnDeadMVar_closure -u
_base_GHCziIOBase_blockedIndefinitely_closure
-u _base_ControlziExceptionziBase_nestedAtomically_closure -u
_base_GHCziWeak_runFinalizzerBatch_closure
-u _base_GHCziTopHandler_runIO_closure -u
_base_GHCziTopHandler_runNonIO_closure
-u _base_GHCziConc_ensureIOManagerIsRunning_closure -o original
-lcrt1.10.5.o -L/Library/Frameworks/GHC.framework/
Versions/610/usr/lib/ghc-6.10.1/mtl-1.1.0.2
-L/Library/Frameworks/GHC.framework/Versions/610/usr/lib/ghc-6.10.1/base-4.0.0.0
-L/Library/Frameworks/GHC.framework/Versions/610/usr/lib/ghc-6.10.1/integer-0.1.0.0
-L/Library/Frameworks/GHC.framework
/Versions/610/usr/lib/ghc-6.10.1/ghc-prim-0.1.0.0
-L/Library/Frameworks/GHC.framework/Versions/610/usr/lib/ghc-6.10.1
-L/usr/lib/i686-apple-darwin9/4.0.1 -L/usr/lib/gcc/i686-apple-
darwin9/4.0.1 -L/usr/lib/gcc/i686-apple-darwin9/4.0.1
-L/usr/lib/gcc/i686-apple-darwin9/4.0.1/../../../i686-apple-darwin9/4.0.1
-L/usr/lib/gcc/i686-apple-darwin9/4.0.1
/../../.. original.o -lHSmtl-1.1.0.2 -lHSbase-4.0.0.0 -lHSinteger-0.1.0.0
-lHSghc-prim-0.1.0.0 -lHSrts -lm
-lffi -lgmp -ldl -search_paths_first -lgcc_s.10.5 -lgcc -lSystem
link: done
*** Deleting temp files:
Deleting:
*** Deleting temp dirs:
Deleting: /var/folders/uZ/uZjvUnuPHNmMwDWLlrsGT++++TI/-Tmp-//ghc13029_0
$ ./original
^C <increasing space usage>
$ ghc -fforce-recomp --make condensed
[1 of 1] Compiling Main ( condensed.hs, condensed.o )
Linking condensed ...
$ ./condensed
^C <constant space>
13:50 memleak$ ghc -O -fforce-recomp --make condensed
[1 of 1] Compiling Main ( condensed.hs, condensed.o )
Linking condensed ...
$ ./condensed
^C <increasing space usage>
}}}
I have checked with ghc-6.8.2 on "Linux 2.6.27-11-generic 1 SMP Wed Apr 1
20:53:41 UTC 2009 x86_64 GNU/Linux" and with ghc-6.10.1 and 6.11.200903331
on "Darwin 9.7.0 Darwin Kernel Version 9.7.0: Tue Mar 31 22:52:17 PDT
2009; root:xnu-1228.12.14~1/RELEASE_I386 i386"
Here are some more runs with -fno-full-laziness and/or -fno-cse. Neither
switch affects the memory requirements with -O:
{{{
$ ghc -fno-full-laziness -O -fforce-recomp --make condensed
[1 of 1] Compiling Main ( condensed.hs, condensed.o )
Linking condensed ...
$ ./condensed
^C <increasing memory usage>
$ ghc -fno-cse -O -fforce-recomp --make condensed
[1 of 1] Compiling Main ( condensed.hs, condensed.o )
Linking condensed ...
$ ./condensed
^C <increasing memory usage>
$ ghc -fno-full-laziness -fno-cse -O -fforce-recomp --make condensed
[1 of 1] Compiling Main ( condensed.hs, condensed.o )
Linking condensed ...
$ ./condensed
^C <increasing memory usage>
}}}
The program original.hs contains an alternative implementation of
'iterDepth' that seems to hint at the problem. I think, the argument of
'runDepthBound' is held in memory for a good reason there.
The program condensed.hs contains four superflous occurrences of 'id' that
seem to play together to cause the memory leak. If all of them are present
then the program uses lots of space with -O, if either one is missing it
runs in constant space. The program always runs in constant space without
-O. I think, the space leak is caused by holding the arguments of 'id' in
memory. If that is true, however, I don't see why *all* occurrences of
'id' are necessary to cause the leak.
I think the original program and all versions of the condensed program
should run in constant space with and without -O. It would be nice if the
alternative version of the original program would run in constant space
too but I see that there is sharing that may prevent this.
--
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3273>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler_______________________________________________
Glasgow-haskell-bugs mailing list
[email protected]
http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
