[GHC] #11784: panic "hscCmmFile: no_mod" with `-v2 and above

[GHC]

#11784: panic "hscCmmFile: no_mod" with `-v2 and above
-------------------------------------+-------------------------------------
        Reporter:  erikd             |                Owner:
            Type:  bug               |               Status:  patch
        Priority:  high              |            Milestone:  8.2.1
       Component:  Compiler          |              Version:  8.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash                              |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D2864
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"222e99d9e6b24c17a67c07d24d05999701b83e96/ghc"
 222e99d9/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="222e99d9e6b24c17a67c07d24d05999701b83e96"
 Make up a module name for c-- files

 Summary:
 We used to pass a bottoming Module to the NCG, which resulted in panics
 when `-v` was used due to debug output (see #11784). Instead we make up
 a module name. This is a bit scary since `PIC.howToAccessLabel` might
 actually use the Module, but if it wasn't crashing before I suppose it's
 fine.

 Test Plan: `touch hi.cmm; ghc -v2 -c -dcmm-lint hi.cmm`

 Reviewers: austin, simonmar

 Reviewed By: simonmar

 Subscribers: thomie

 Differential Revision: https://phabricator.haskell.org/D2864

 GHC Trac Issues: #11784
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11784#comment:5>
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