[GHC] #9010: TemplateHaskell leads to an "unknown symbol" error

[GHC]

#9010: TemplateHaskell leads to an "unknown symbol" error
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        Reporter:  Feuerbach         |                Owner:
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:
       Component:  Compiler          |              Version:  7.10.2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by basvandijk):

 Regarding the symbol in question, note that according to
 http://demangler.com/ the mangled symbol
 `_ZGVZN2cv9v_invsqrtERKNS_11v_float32x4EE4_0_5` demangles to:

 {{{
    guard variable for cv::v_invsqrt(cv::v_float32x4 const&)::_0_5
 }}}

 It is defined here:
 https://github.com/Itseez/opencv/blob/3.0.0/modules/hal/include/opencv2/hal/intrin_sse.hpp#L683

 And it indeed occurs in `libopencv_hal.a`:

 {{{
  nm /nix/store/1wyif1adq0pb9h08jqr0v5lrykfhdhah-
 opencv-3.0.0/lib/libopencv_hal.a 2>/dev/null | grep
 _ZGVZN2cv9v_invsqrtERKNS_11v_float32x4EE4_0_5
 0000000000000000 u _ZGVZN2cv9v_invsqrtERKNS_11v_float32x4EE4_0_5
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9010#comment:7>
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