[GHC] #9620: libffi.a is put in the wrong folder

[GHC]

#9620: libffi.a is put in the wrong folder
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              Reporter:  rezb1t      |            Owner:
                  Type:  bug         |           Status:  new
              Priority:  normal      |        Milestone:  7.10.1
             Component:  Build       |          Version:  7.9
  System                             |         Keywords:  libffi lib64
            Resolution:              |     Architecture:  Unknown/Multiple
      Operating System:  Linux       |       Difficulty:  Unknown
       Type of failure:  Building    |       Blocked By:
  GHC failed                         |  Related Tickets:
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
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Comment (by rwbarton):

 Well it's not accidental. ghc's build system configures libffi with
 `--libdir=$(TOP)/libffi/build/inst/lib` with the intention that libffi
 should install its libraries into `libffi/build/inst/lib`. However libffi
 insists on installing its libraries into this mysterious "toolexeclibdir"
 instead.

 Seems like Gentoo ran into the same issue when packaging libffi:
 https://sourceware.org/ml/libffi-discuss/2014/msg00016.html

 Maybe we can adopt their workaround of `sed -i
 's:@toolexeclibdir@:$(libdir):g' Makefile.in` before running libffi's
 configure script.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9620#comment:7>
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