[GHC] #13185: haskell-relational-query: ghc: panic! (the 'impossible' happened)

[GHC]

#13185: haskell-relational-query: ghc: panic! (the 'impossible' happened)
-------------------------------------+-------------------------------------
        Reporter:  LocutusOfBorg     |                Owner:
            Type:  bug               |               Status:  infoneeded
        Priority:  high              |            Milestone:
       Component:  Compiler          |              Version:  8.0.2
      Resolution:                    |             Keywords:
Operating System:  Linux             |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Compile-time      |            Test Case:  build
  crash or panic                     |  relational-query with ghc 8.0.2
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Changes (by mpickering):

 * status:  new => infoneeded


@@ -7,0 +7,1 @@
+ {{{
@@ -29,0 +30,1 @@
+ }}}

New description:

 Hello, this seems a regression of ghc 8.0.2 since 8.0.1 was building it
 fine:
 https://launchpadlibrarian.net/303858976/buildlog_ubuntu-zesty-amd64
 .haskell-relational-query_0.8.3.2-2build1_BUILDING.txt.gz

 as you can see in the build log:
 {{{
 Preprocessing test suite 'sqls' for relational-query-0.8.3.2...
 [1 of 3] Compiling Model            ( test/Model.hs, dist-ghc/build/sqls
 /sqls-tmp/Model.o )
 [2 of 3] Compiling Lex              ( test/Lex.hs, dist-ghc/build/sqls
 /sqls-tmp/Lex.o )
 [3 of 3] Compiling Main             ( test/sqlsEq.hs, dist-ghc/build/sqls
 /sqls-tmp/Main.o )
 ghc: panic! (the 'impossible' happened)
   (GHC version 8.0.2 for x86_64-unknown-linux):
         Simplifier ticks exhausted
   When trying UnfoldingDone runReaderT
   To increase the limit, use -fsimpl-tick-factor=N (default 100)
   If you need to do this, let GHC HQ know, and what factor you needed
   To see detailed counts use -ddump-simpl-stats
   Total ticks: 405365

 Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

 /usr/share/cdbs/1/class/hlibrary.mk:147: recipe for target 'build-ghc-
 stamp' failed
 make: *** [build-ghc-stamp] Error 1
 dpkg-buildpackage: error: debian/rules build gave error exit status 2
 }}}

 thanks,

 Gianfranco

--

Comment:

 Please provide instructions how to reproduce this so we can investigate.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13185#comment:1>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler