[GHC] #16378: bkpcabal01 fails with recent Cabal

[GHC]

#16378: bkpcabal01 fails with recent Cabal
-------------------------------------+-------------------------------------
        Reporter:  bgamari           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.8.1
       Component:  Compiler          |              Version:  8.6.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------

Comment (by bgamari):

 Adding `-v2` to the failing `Setup configure` invocation reveals these
 differences:
 {{{#!patch
 --- good        2019-03-05 04:17:02.545005732 +0000
 +++ bad 2019-03-05 04:17:23.240399325 +0000
 @@ -1,39 +1,38 @@
  .
  .
  .
 -+ ./Setup -v2 configure --enable-library-vanilla --disable-shared --with-
 ghc=/nix/store/y6vdn971gmxziv4ryqqbaf1iy814i2z1-ghc-build-
 environment/bin/ghc '--ghc-options=-dcore-lint -dstg-lint -dcmm-lint -no-
 user-package-db -rtsopts  -fno-warn-missed-specialisations -fshow-warning-
 groups -fdiagnostics-color=never -fno-diagnostics-show-caret
 -Werror=compat -dno-debug-output' --package-db=tmp.d
 --prefix=/home/ben/ghc/ghc-8.8/testsuite/tests/backpack/cabal/bkpcabal01/inst
 --cid q-0.1 q
 ++ ./Setup -v2 configure --enable-library-vanilla --disable-shared --with-
 ghc=/home/ben/ghc/ghc-8.8/inplace/bin/ghc-stage2 '--ghc-options=-dcore-
 lint -dstg-lint -dcmm-lint -no-user-package-db -rtsopts  -fno-warn-missed-
 specialisations -fshow-warning-groups -fdiagnostics-color=never -fno-
 diagnostics-show-caret -Werror=compat -dno-debug-output' --package-
 db=tmp.d
 --prefix=/home/ben/ghc/ghc-8.8/testsuite/tests/backpack/cabal/bkpcabal01/inst
 --cid q-0.1 q
  Using Parsec parser
  Configuring library 'q' for bkpcabal01-0.1.0.0..
 -Dependency base -any: using base-4.11.1.0
 +Dependency base -any: using base-4.12.0.0
  Dependency impl -any: using bkpcabal01-0.1.0.0
  Dependency p -any: using bkpcabal01-0.1.0.0
 -
 -on the commandline: warning:
 -    unrecognised warning flag: -Werror=compat
  Source component graph:
      component lib:q
 -        dependency lib:p
          dependency lib:impl
 +        dependency lib:p
  Configured component graph:
      component q-0.1
          include impl-0.1 (H)
 +        include base-4.12.0.0
          include p-0.1
 -        include base-4.11.1.0
  Linked component graph:
      unit q-0.1[I=<I>]
          include impl-0.1 (H)
 +        include base-4.12.0.0
          include p-0.1[H=impl-0.1:H]
 -        include base-4.11.1.0
          Q=q-0.1[I=<I>]:Q
  Ready component graph:
      indefinite q-0.1
          depends impl-0.1
 -        depends p-0.1
 -        depends base-4.11.1.0
 -Using Cabal-2.2.0.1 compiled by ghc-8.4
 -Using compiler: ghc-8.4.3
 -Using install prefix:
 -/home/ben/ghc/ghc-8.8/testsuite/tests/backpack/cabal/bkpcabal01/inst
 +        depends base-4.12.0.0
 +        depends p-0.1+FBOSaiWyMx9DR2UZVI6wQJ
 +CallStack (from HasCallStack):
 +  dieNoWrap, called at
 libraries/Cabal/Cabal/Distribution/Utils/LogProgress.hs:61:9 in
 Cabal-2.5.0.0:Distribution.Utils.LogProgress
 +Error:
 +    The following packages are broken because other packages they depend
 on are missing. These broken packages must be rebuilt before they can be
 used.
 +planned package bkpcabal01-0.1.0.0 is broken due to missing package
 p-0.1+FBOSaiWyMx9DR2UZVI6wQJ
 +
  .
  .
  .

 }}}

 Not particularly illuminating.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16378#comment:3>
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