Re: How to force -fPIC on package builds?

I've made more explicit how to setup the docker container in the issue tracker: https://github.com/tweag/HaskellR/issues/257#issuecomment-239759880 -- Mathieu Boespflug Founder at http://tweag.io. On 14 August 2016 at 23:49, Dominick Samperi wrote:

Thanks for looking into this Mathieu. I have been using this hsc2hs flag all along, and it has enabled me to build inline-r, but the build of H fails (using ghc-8.0.1). As you mention in your issue tracker, the new twist is to add ghc-options: -dynamic to the cabal file for H (and for any binary that links to inline-r).

BTW, how can I compare my results with yours if all I know is that you have used "a docker container"? Wouldn't I need to know what repository and snapshot you are using?

...

I was able to reproduce in a docker container and tracked down the

On Sun, Aug 14, 2016 at 2:55 PM, Boespflug, Mathieu wrote: source of

...

the issue: https://github.com/tweag/HaskellR/issues/257

The executive summary is that if Cabal is asking hsc2hs to link to a dynamic library, then it should pass --cflag=-fPIC to hsc2hs. Otherwise hsc2hs might fail, because then it might be impossible to link the temporary object files that it creates with the shared library.

A workaround is to set "cc-options: -fPIC" in the .cabal file. But in my mind this is probably a Cabal bug.

-- Mathieu Boespflug Founder at http://tweag.io.

On 14 August 2016 at 06:12, Dominick Samperi wrote:

...

I should add that H builds and runs nicely under Windows and MacOS (using ghc 8.0.1), so this is indeed a Fedora Linux issue.

On Sat, Aug 13, 2016 at 10:22 AM, Dominick Samperi

...

wrote:

...

Hello Mathieu,

I'm using Fedora 23. The default Haskell Platform here provides ghc 7.8.4, and this seems to have even more problems. Thus I have been trying to use ghc 8.0.1 compiled from source. I think the red herring bit may apply to 32 bit builds, but I am attempting a 64 bit build. The problem may be related to the way modules are randomly relocated for security reasons, Fedora security policies, and confusion/bugs in the linker(s).

Cheers, Dominick

On Sat, Aug 13, 2016 at 7:43 AM, Boespflug, Mathieu wrote:

...

Hi Dominick,

which version of Fedora Linux are you on? The -fPIC message from the linker may well be a red herring. AFAIR generating PIC is the default in GHC, at least for dynamic libraries.

Best,

-- Mathieu Boespflug Founder at http://tweag.io.

On 13 August 2016 at 05:55, Dominick Samperi wrote:

...

Hello,

I am getting relocation errors when building an executable (specifically, the "H" executable -- part of haskellR) under Fedora Linux, and the message says to "recompile with -fPIC".

The FAQ associated with H suggests that I switch to the gold linker (ld.gold) due to bugs in the default linker (ld.bfd), but this only changes the wording of the relocation error messages.

I have tried several strategies for satisfying the -fPIC

requirement:

...

1. In cabal files I insert cc-options: and ghc-options: lines including -fPIC 2. To the 'cabal install' command line I add: --ghc-option=-fPIC --hsc2hs-option=-cflag=-fPIC 3. When building ghc 8.0.1 from source I modify config.mk by including: CONF_CC_OPTS += -fPIC SRC_HSC2HS_OPTS += --cflag=-fPIC CONF_CC_OPTS_STAGE0 = -fno-stack-protector -fPIC [same for STAGE1 and STAGE2]

All of this doesn't fix the problem, and the error messages still say "recompile with -fPIC".

This may be a bug, but I'm not sure where. Any ideas?

Thanks, Dominick _______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs