Rename PackageId to PackageKey, distinguishing it from Cabal's PackageId.

Summary:
Previously, both Cabal and GHC defined the type PackageId, and we expected
them to be roughly equivalent (but represented differently).  This refactoring
separates these two notions.

A package ID is a user-visible identifier; it's the thing you write in a
Cabal file, e.g. containers-0.9.  The components of this ID are semantically
meaningful, and decompose into a package name and a package vrsion.

A package key is an opaque identifier used by GHC to generate linking symbols.
Presently, it just consists of a package name and a package version, but
pursuant to #9265 we are planning to extend it to record other information.
Within a single executable, it uniquely identifies a package.  It is *not* an
InstalledPackageId, as the choice of a package key affects the ABI of a package
(whereas an InstalledPackageId is computed after compilation.)  Cabal computes
a package key for the package and passes it to GHC using -package-name (now
*extremely* misnamed).

As an added bonus, we don't have to worry about shadowing anymore.

As a follow on, we should introduce -current-package-key having the same role as
-package-name, and deprecate the old flag.  This commit is just renaming.

The haddock submodule needed to be updated.

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

Test Plan: validate

Reviewers: simonpj, simonmar, hvr, austin

Subscribers: simonmar, relrod, carter

Differential Revision: https://phabricator.haskell.org/D79

Conflicts:
	compiler/main/HscTypes.lhs
	compiler/main/Packages.lhs
	utils/haddock

1 files changed, 2 insertions, 2 deletions

diff --git a/compiler/cmm/CmmParse.y b/compiler/cmm/CmmParse.y
index 49143170c3..803333001c 100644
--- a/compiler/cmm/CmmParse.y
+++ b/compiler/cmm/CmmParse.y
@@ -573,7 +573,7 @@ importName
 
         -- A label imported with an explicit packageId.
         | STRING NAME
-        { ($2, mkCmmCodeLabel (fsToPackageId (mkFastString $1)) $2) }
+        { ($2, mkCmmCodeLabel (fsToPackageKey (mkFastString $1)) $2) }
         
         
 names   :: { [FastString] }
@@ -1101,7 +1101,7 @@ profilingInfo dflags desc_str ty_str
     else ProfilingInfo (stringToWord8s desc_str)
                        (stringToWord8s ty_str)
 
-staticClosure :: PackageId -> FastString -> FastString -> [CmmLit] -> CmmParse ()
+staticClosure :: PackageKey -> FastString -> FastString -> [CmmLit] -> CmmParse ()
 staticClosure pkg cl_label info payload
   = do dflags <- getDynFlags
        let lits = mkStaticClosure dflags (mkCmmInfoLabel pkg info) dontCareCCS payload [] [] []