[GHC] #11587: Place shared objects in LIBDIR

[GHC]

#11587: Place shared objects in LIBDIR
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        Reporter:  bgamari           |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.2.1
       Component:  Package system    |              Version:  7.10.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by duncan):

 Note that some more sharing is possible, given typical layouts.

 For example for nix or for cabal new-build we install into a store.

 {{{
 $store/$pkgid-$hash/libHSpkgname-ver.so
 }}}

 (Currently it's actually worse than this since the libname includes hashes
 too, which should be unnecessary given the separated dirs)

 I'm not sure if this is possible with ELF, but if we can include part of
 the directory into the libname / location, and a separate RUN_PATH then we
 could use a scheme like:

 {{{
 RUN_PATH /home/me/.cabal/store
 SO_NEEDED pkgname-ver-hash/libHSpkgname-ver.so
 SO_NEEDED ...
 }}}

 This does appear to be possible with MachO, ie like:
 {{{
 LC_RPATH /home/me/.cabal/store
 LC_LOAD_DYLIB @rpath/pkgname-ver-hash/libHSpkgname-ver.dynlib
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11587#comment:7>
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