Update Cabal to HEAD, IPID renamed to Component ID.

This commit contains a Cabal submodule update which unifies installed
package IDs and package keys under a single notion, a Component ID.
We update GHC to keep follow this unification.  However, this commit
does NOT rename installed package ID to component ID and package key to
unit ID; the plan is to do that in a companion commit.

    - Compiler info now has "Requires unified installed package IDs"

    - 'exposed' is now expected to contain unit keys, not IPIDs.

    - Shadowing is no more.  We now just have a very simple strategy
      to deal with duplicate unit keys in combined package databases:
      if their ABIs are the same, use the latest one; otherwise error.
      Package databases maintain the invariant that there can only
      be one entry of a unit ID.

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Test Plan: validate

Reviewers: simonpj, austin, bgamari, hvr, goldfire

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1184

GHC Trac Issues: #10714

1 files changed, 1 insertions, 0 deletions

diff --git a/testsuite/.gitignore b/testsuite/.gitignore
index a1481ad1ce..a2b645429b 100644
--- a/testsuite/.gitignore
+++ b/testsuite/.gitignore
@@ -128,6 +128,7 @@ mk/ghcconfig*_bin_ghc*.exe.mk
 /tests/cabal/localT1750.package.conf/
 /tests/cabal/localshadow1.package.conf/
 /tests/cabal/localshadow2.package.conf/
+/tests/cabal/localshadow3.package.conf/
 /tests/cabal/package.conf.*/
 /tests/cabal/recache_reexport_db/package.cache
 /tests/cabal/shadow.hs