#8376: Static Executable + GHC API (+ Dynamic Linking?) gives Segfault ----------------------------------+---------------------------------- Reporter: darchon | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.7 Keywords: | Operating System: MacOS X Architecture: x86_64 (amd64) | Type of failure: Runtime crash Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ----------------------------------+---------------------------------- I am getting segfaults when a statically linked executable uses a GHC API. When the same executable is however dynamically linked it runs without error. In case of the statically-linked version, I think that one of GHC API functions that tries to do dynamic-linking is causing the segfault. The reason why I think this, is because the segfault shows up when Template-Haskell is used, or when {{{ {-# ANN ... #-} }}} annotations are used. An example of this strange behaviour can be shown using haddock, and running it on the source-code for the lens library [1]: {{{ ~/Documents/devel/lens/src (master *)$ haddock -v3 Control/Lens/Internal/ByteString.hs Creating interfaces... Haddock coverage: Checking module Control.Lens.Internal.Setter... Creating interface... 100% ( 3 / 3) in 'Control.Lens.Internal.Setter' <MORE LOG MESSAGE> Checking module Control.Lens.Reified... Creating interface... 100% ( 20 / 20) in 'Control.Lens.Reified' Checking module Control.Lens.Setter... Bus error: 10 <-- SEGFAULT }}} And the GDB output: {{{ (gdb) run -v3 Control/Lens/Internal/ByteString.hs Starting program: /Users/christiaan/.ghc- config/cabal/7.7.20130924/bin/haddock -v3 Control/Lens/Internal/ByteString.hs Reading symbols for shared libraries +++.............................. done Creating interfaces... Haddock coverage: Checking module Control.Lens.Internal.Setter... Creating interface... 100% ( 3 / 3) in 'Control.Lens.Internal.Setter' <MORE LOG MESSAGES> Checking module Control.Lens.Reified... Creating interface... 100% ( 20 / 20) in 'Control.Lens.Reified' Checking module Control.Lens.Setter... Program received signal EXC_BAD_ACCESS, Could not access memory. Reason: KERN_PROTECTION_FAILURE at address: 0x000000010828b982 0x000000010828b982 in ?? () }}} I should note that until now I've been unable to produce a _small_ test case that shows the above behaviour. The statically linked haddock actually runs successfully on many packages. The lens[1] package is the first widely used library that I've been able to get haddock to exhibit the above behaviour. Also, when I built a dynamically-linked version of haddock, it runs succesfully for the above test-case (and the other test-cases where the statically-linked version would give a segfault). The source-code for lens[1] contains many {{{ {-# ANN ... #-} }}} annotations; removing all those annotations make the statically-linked version of haddock run successfully, with out segfaults. Halfway through removing the {{{ {-# ANN ... #-} }}} annotation, I also encountered the following error: {{{ Checking module Control.Lens.Fold... haddock: internal error: ARR_WORDS object entered! (GHC version 7.7.20130924 for x86_64_apple_darwin) Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug Abort trap: 6 }}} I've also encountered the segfault while running the statically-linked haddock on my own clash library [2]. In this case I think it might have something to do with the use of template-haskell. Again, running the dynamically-linked version of haddock does not show any problems. Here is some extra information about my development environment:[[BR]] OS: OS X 10.8.5[[BR]] X-Code: XCode CL-Tools 4.6.2[[BR]] GHC: GHC-HEAD (commit 94ab5d2984514f92dd919fbf3611a07d32105546)[[BR]] Output of {{{make show VALUE=GhcLibWays}}}: v dyn[[BR]] build.mk: {{{ SRC_HC_OPTS = -O -H64m GhcStage1HcOpts = -O -fasm GhcStage2HcOpts = -O2 -fasm GhcHcOpts = -Rghc-timing GhcLibHcOpts = -O2 HADDOCK_DOCS = NO }}} I create statically-linked binaries by setting {{{executable-dynamic}}} in {{{.cabal/config}}} to {{{False}}}[[BR]] I create dynamically-linked binaries by setting {{{executable-dynamic}}} in {{{.cabal/config}}} to {{{True}}}[[BR]] I created the {{{haddock}}} executables by running {{{cabal install}}} in {{{"up-to-date build tree of GHC"/utils/haddock}}} [1] https://github.com/ekmett/lens[[BR]] [2] http://hackage.haskell.org/package/clash-lib -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8376 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler