[GHC] #12504: Windows: Using hsc2hs in combination with inline-c generates the .c files with invalid paths

[GHC]

#12504: Windows: Using hsc2hs in combination with inline-c generates the .c files
with invalid paths
-------------------------------------+-------------------------------------
        Reporter:  rcook             |                Owner:
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  hsc2hs            |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Windows           |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Other             |            Test Case:
                                     |  /testsuite/tests/hsc2hs/T12504/path/to/T12504.hsc
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D2478
       Wiki Page:                    |
-------------------------------------+-------------------------------------

Comment (by Ben Gamari <ben@…>):

 In [changeset:"2ee1db60ab29258fa9f8ab820f778bd0bb7f87a4/ghc"
 2ee1db60/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="2ee1db60ab29258fa9f8ab820f778bd0bb7f87a4"
 Fixes #12504: Double-escape paths used to build call to hsc_line

 In outHsLine, paths passed to construct invocations of hsc_line must be
 escaped twice in order to generate a properly escaped string literal
 that will end up in the eventual LINE pragma emitted by this code. This
 is especially important on Windows paths, where backslashes would
 otherwise be treated as C escape sequences and result in the incorrect
 Windows paths.

 Adds test case to verify that hsc2hs properly escapes file paths in LINE
 pragmas

 Updates the hsc2hs submodule.

 See https://ghc.haskell.org/trac/ghc/ticket/12504

 Reviewers: erikd, hvr, austin, bgamari, Phyx

 Reviewed By: erikd, Phyx

 Subscribers: thomie, Phyx, mpickering

 Differential Revision: https://phabricator.haskell.org/D2478

 GHC Trac Issues: #12504
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12504#comment:10>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler