[GHC] #7779: building GHC overwrites the installed package database if GHC_PACKAGE_PATH is set

[GHC]

#7779: building GHC overwrites the installed package database if GHC_PACKAGE_PATH
is set
-------------------------------------+------------------------------------
        Reporter:  heatsink          |            Owner:
            Type:  bug               |           Status:  new
        Priority:  normal            |        Milestone:  7.8.1
       Component:  Build System      |          Version:  7.4.2
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Changes (by igloo):

 * owner:  igloo =>


Comment:

 Ah, I suspect you have an old version of `cabal`; it looks like 1.14
 doesn't mind `GHC_PACKAGE_PATH` being set. But in 1.16 it just fails:
 {{{
 $ cabal --version
 cabal-install version 1.16.0.2
 using version 1.16.0 of the Cabal library

 $ export GHC_PACKAGE_PATH=something

 $ cabal install text
 cabal: Use of GHC's environment variable GHC_PACKAGE_PATH is incompatible
 with
 Cabal. Use the flag --package-db to specify a package database (it can be
 used
 multiple times).

 $ echo $?
 1
 }}}

 You can use flags such as `-package-db` and `-global-package-db` with GHC
 too.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7779#comment:4>
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