[GHC] #15279: CPP #includes may result in nonsensical SrcSpans

[GHC]

#15279: CPP #includes may result in nonsensical SrcSpans
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        Reporter:  wz1000            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:  cpp
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Other             |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #14113            |  Differential Rev(s):  Phab:D4866
       Wiki Page:                    |
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Comment (by Krzysztof Gogolewski <krz.gogolewski@…>):

 In [changeset:"f7f9820e8f5601e9a072e504f3d772fd78df6700/ghc" f7f9820/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="f7f9820e8f5601e9a072e504f3d772fd78df6700"
 Check if files are same in combineSrcSpans

 Summary: If this is not checked, SrcSpans are sometimes mangled by CPP.

 Test Plan: ./validate

 Reviewers: bgamari, dfeuer

 Reviewed By: bgamari

 Subscribers: dfeuer, rwbarton, thomie, carter

 GHC Trac Issues: #15279

 Differential Revision: https://phabricator.haskell.org/D4866
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15279#comment:5>
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