[GHC] #10618: HEAD at d71b65f53a panics: ``get_op (--$)''

[GHC]

#10618: HEAD at d71b65f53a panics: ``get_op (--$)''
-------------------------------------+-------------------------------------
              Reporter:  bjmprice    |             Owner:
                  Type:  bug         |            Status:  new
              Priority:  normal      |         Milestone:
             Component:  Compiler    |           Version:  7.11
              Keywords:              |  Operating System:  Linux
          Architecture:  x86_64      |   Type of failure:  Compile-time
  (amd64)                            |  crash
             Test Case:              |        Blocked By:
              Blocking:              |   Related Tickets:
Differential Revisions:              |
-------------------------------------+-------------------------------------
 (Note that 7.10.1 works as expected)

 This one line generates a panic:
 {{{#!hs
 panic = GarbageConstructorName $ a --$ b
 }}}
 (in an otherwise blank file, when passed to {{{ghc }}} or {{{ghci}}}. Just
 the right hand side panics {{{ghci}}} interactively.)

 Error message:
 {{{
 ghc-stage2: panic! (the 'impossible' happened)
   (GHC version 7.11.20150708 for x86_64-unknown-linux):
         get_op (--$)

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

 {{{uname -a: Linux cam-05-unx 3.5.0-54-generic #81~precise1-Ubuntu SMP Tue
 Jul 15 04:02:22 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux}}}
 {{{
 gcc -v:
 Using built-in specs.
 COLLECT_GCC=gcc
 COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/4.6/lto-wrapper
 Target: x86_64-linux-gnu
 Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro
 4.6.3-1ubuntu5' --with-bugurl=file:///usr/share/doc/gcc-4.6/README.Bugs
 --enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr --program-
 suffix=-4.6 --enable-shared --enable-linker-build-id --with-system-zlib
 --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
 --with-gxx-include-dir=/usr/include/c++/4.6 --libdir=/usr/lib --enable-nls
 --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-
 libstdcxx-time=yes --enable-gnu-unique-object --enable-plugin --enable-
 objc-gc --disable-werror --with-arch-32=i686 --with-tune=generic --enable-
 checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu
 --target=x86_64-linux-gnu
 Thread model: posix
 gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5)
 }}}

 With {{{ghc -v}}} (Was built with {{{BuildFlavour = devel2}}}, default
 {{{build.mk}}} otherwise):
 {{{
 Glasgow Haskell Compiler, Version 7.11.20150708, stage 2 booted by GHC
 version 7.8.2
 Using binary package database: /5playpen/t-bepric/ghc-
 build/inplace/lib/package.conf.d/package.cache
 wired-in package ghc-prim mapped to ghc-prim-0.4.0.0-inplace
 wired-in package integer-gmp mapped to integer-gmp-1.0.0.0-inplace
 wired-in package base mapped to base-4.8.2.0-inplace
 wired-in package rts mapped to builtin_rts
 wired-in package template-haskell mapped to template-
 haskell-2.10.0.0-inplace
 wired-in package ghc mapped to ghc-7.11.20150708-inplace
 wired-in package dph-seq not found.
 wired-in package dph-par not found.
 Hsc static flags:
 wired-in package ghc-prim mapped to ghc-prim-0.4.0.0-inplace
 wired-in package integer-gmp mapped to integer-gmp-1.0.0.0-inplace
 wired-in package base mapped to base-4.8.2.0-inplace
 wired-in package rts mapped to builtin_rts
 wired-in package template-haskell mapped to template-
 haskell-2.10.0.0-inplace
 wired-in package ghc mapped to ghc-7.11.20150708-inplace
 wired-in package dph-seq not found.
 wired-in package dph-par not found.
 *** Chasing dependencies:
 Chasing modules from: *GetOpCrash.hs
 Stable obj: []
 Stable BCO: []
 Ready for upsweep
   [NONREC
       ModSummary {
          ms_hs_date = 2015-07-08 15:09:13 UTC
          ms_mod = Main,
          ms_textual_imps = [import (implicit) Prelude]
          ms_srcimps = []
       }]
 *** Deleting temp files:
 Deleting:
 compile: input file GetOpCrash.hs
 Created temporary directory: /tmp/ghc22576_0
 *** Checking old interface for Main:
 [1 of 1] Compiling Main             ( GetOpCrash.hs, GetOpCrash.o )
 *** Parser:
 *** Renamer/typechecker:
 *** Deleting temp files:
 Deleting: /tmp/ghc22576_0/ghc_1.s
 Warning: deleting non-existent /tmp/ghc22576_0/ghc_1.s
 *** Deleting temp dirs:
 Deleting: /tmp/ghc22576_0
 ghc-stage2: panic! (the 'impossible' happened)
   (GHC version 7.11.20150708 for x86_64-unknown-linux):
         get_op (--$)
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10618>
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