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, 4 insertions, 4 deletions

diff --git a/testsuite/tests/cabal/shadow.stderr b/testsuite/tests/cabal/shadow.stderr
index a0a38cde22..3825896e85 100644
--- a/testsuite/tests/cabal/shadow.stderr
+++ b/testsuite/tests/cabal/shadow.stderr
@@ -1,4 +1,4 @@
-<command line>: cannot satisfy -package shadowdep: 
-    shadowdep-1-XXX is unusable due to missing or recursive dependencies:
-      shadow-1-XXX
-    (use -v for more information)
+<command line>: package db: duplicate packages with incompatible ABIs:
+    shadow-1-XXX has ABIs: aaa, bbb
+<command line>: package db: duplicate packages with incompatible ABIs:
+    shadow-1-XXX has ABIs: aaa, bbb