Revert "ghc-pkg: recompute `abi-depends` for updated packages"

This reverts commit 1cdc14f9c014f1a520638f7c0a01799ac6d104e6.

This is causing non-deterministic testsuite output.

11 files changed, 9 insertions, 82 deletions

diff --git a/testsuite/tests/backpack/cabal/bkpcabal02/bkpcabal02.stdout b/testsuite/tests/backpack/cabal/bkpcabal02/bkpcabal02.stdout
index 1e51c3c4ac..2f17fdffcd 100644
--- a/testsuite/tests/backpack/cabal/bkpcabal02/bkpcabal02.stdout
+++ b/testsuite/tests/backpack/cabal/bkpcabal02/bkpcabal02.stdout
@@ -1,11 +1,6 @@
-ignoring (possibly broken) abi-depends field for packages
-ignoring (possibly broken) abi-depends field for packages
 Preprocessing library 'p' for bkpcabal01-0.1.0.0..
 Building library 'p' instantiated with H = <H>
 for bkpcabal01-0.1.0.0..
-ignoring (possibly broken) abi-depends field for packages
 Preprocessing library 'q' for bkpcabal01-0.1.0.0..
 Building library 'q' instantiated with H = <H>
 for bkpcabal01-0.1.0.0..
-ignoring (possibly broken) abi-depends field for packages
-ignoring (possibly broken) abi-depends field for packages
diff --git a/testsuite/tests/cabal/T12485a.stdout b/testsuite/tests/cabal/T12485a.stdout
index af722c524a..ee83ab293c 100644
--- a/testsuite/tests/cabal/T12485a.stdout
+++ b/testsuite/tests/cabal/T12485a.stdout
@@ -1,4 +1,3 @@
-ignoring (possibly broken) abi-depends field for packages
 should SUCCEED
 should SUCCEED
 should SUCCEED
diff --git a/testsuite/tests/cabal/T5442d.stdout b/testsuite/tests/cabal/T5442d.stdout
index 0cb7375fbf..f3214578d2 100644
--- a/testsuite/tests/cabal/T5442d.stdout
+++ b/testsuite/tests/cabal/T5442d.stdout
@@ -1,7 +1,6 @@
 Reading package info from "shadow1.pkg" ... done.
 Reading package info from "shadow4.pkg" ... done.
 Reading package info from "shadow2.pkg" ... done.
-ignoring (possibly broken) abi-depends field for packages
 global (should be empty):
 user:
 shadow-2
diff --git a/testsuite/tests/cabal/cabal01/cabal01.stdout b/testsuite/tests/cabal/cabal01/cabal01.stdout
index 1378031cb1..e828cbe68a 100644
--- a/testsuite/tests/cabal/cabal01/cabal01.stdout
+++ b/testsuite/tests/cabal/cabal01/cabal01.stdout
@@ -1,4 +1,3 @@
-ignoring (possibly broken) abi-depends field for packages
 install1:
 bin
 lib
diff --git a/testsuite/tests/cabal/cabal06/cabal06.stdout b/testsuite/tests/cabal/cabal06/cabal06.stdout
index 381363977c..e5ff042302 100644
--- a/testsuite/tests/cabal/cabal06/cabal06.stdout
+++ b/testsuite/tests/cabal/cabal06/cabal06.stdout
@@ -1,7 +1,3 @@
-ignoring (possibly broken) abi-depends field for packages
-ignoring (possibly broken) abi-depends field for packages
-ignoring (possibly broken) abi-depends field for packages
-ignoring (possibly broken) abi-depends field for packages
 Does the first instance of q depend on p-1.0?
 1
 Does the second instance of q depend on p-1.0?
diff --git a/testsuite/tests/cabal/cabal08/cabal08.stdout b/testsuite/tests/cabal/cabal08/cabal08.stdout
index d70d778151..06a164b150 100644
--- a/testsuite/tests/cabal/cabal08/cabal08.stdout
+++ b/testsuite/tests/cabal/cabal08/cabal08.stdout
@@ -1,5 +1,3 @@
-ignoring (possibly broken) abi-depends field for packages
-ignoring (possibly broken) abi-depends field for packages
 [1 of 1] Compiling Main             ( Main.hs, Main.o )
 Linking Main ...
 p2
diff --git a/testsuite/tests/cabal/shadow.stdout b/testsuite/tests/cabal/shadow.stdout
index c70767da1d..a47ce15795 100644
--- a/testsuite/tests/cabal/shadow.stdout
+++ b/testsuite/tests/cabal/shadow.stdout
@@ -1,4 +1,3 @@
-ignoring (possibly broken) abi-depends field for packages
 databases 1 and 2:
 localshadow1.package.conf
     (shadow-1)
diff --git a/testsuite/tests/driver/recomp007/recomp007.stdout b/testsuite/tests/driver/recomp007/recomp007.stdout
index d5da3dae18..d8343152e0 100644
--- a/testsuite/tests/driver/recomp007/recomp007.stdout
+++ b/testsuite/tests/driver/recomp007/recomp007.stdout
@@ -1,5 +1,3 @@
-ignoring (possibly broken) abi-depends field for packages
-ignoring (possibly broken) abi-depends field for packages
 Preprocessing executable 'test' for b-1.0..
 Building executable 'test' for b-1.0..
 [1 of 2] Compiling B                ( B.hs, dist/build/test/test-tmp/B.o ) [A changed]
diff --git a/testsuite/tests/safeHaskell/check/pkg01/safePkg01.stdout b/testsuite/tests/safeHaskell/check/pkg01/safePkg01.stdout
index 8d6378430b..59886cd378 100644
--- a/testsuite/tests/safeHaskell/check/pkg01/safePkg01.stdout
+++ b/testsuite/tests/safeHaskell/check/pkg01/safePkg01.stdout
@@ -1,53 +1,49 @@
-ignoring (possibly broken) abi-depends field for packages
 pdb.safePkg01/local.db
     safePkg01-1.0
 
 trusted: False
 
 M_SafePkg
-package dependencies: base-4.11.0.0* ghc-prim-0.5.2.0 integer-gmp-1.0.1.0
+package dependencies: base-4.9.0.0* ghc-prim-0.5.0.0 integer-gmp-1.0.0.0
 trusted: safe
 require own pkg trusted: False
 
 M_SafePkg2
-package dependencies: base-4.11.0.0 ghc-prim-0.5.2.0 integer-gmp-1.0.1.0
+package dependencies: base-4.9.0.0 ghc-prim-0.5.0.0 integer-gmp-1.0.0.0
 trusted: trustworthy
 require own pkg trusted: False
 
 M_SafePkg3
-package dependencies: base-4.11.0.0* ghc-prim-0.5.2.0 integer-gmp-1.0.1.0
+package dependencies: base-4.9.0.0* ghc-prim-0.5.0.0 integer-gmp-1.0.0.0
 trusted: safe
 require own pkg trusted: True
 
 M_SafePkg4
-package dependencies: base-4.11.0.0* ghc-prim-0.5.2.0 integer-gmp-1.0.1.0
+package dependencies: base-4.9.0.0* ghc-prim-0.5.0.0 integer-gmp-1.0.0.0
 trusted: safe
 require own pkg trusted: True
 
 M_SafePkg5
-package dependencies: base-4.11.0.0* ghc-prim-0.5.2.0 integer-gmp-1.0.1.0
+package dependencies: base-4.9.0.0* ghc-prim-0.5.0.0 integer-gmp-1.0.0.0
 trusted: safe
 require own pkg trusted: True
 
 M_SafePkg6
-package dependencies: array-0.5.2.0 base-4.11.0.0* bytestring-0.10.8.2* deepseq-1.4.3.0 ghc-prim-0.5.2.0 integer-gmp-1.0.1.0
+package dependencies: array-0.5.1.0 base-4.9.0.0* bytestring-0.10.7.0* deepseq-1.4.2.0 ghc-prim-0.5.0.0 integer-gmp-1.0.0.0
 trusted: trustworthy
 require own pkg trusted: False
 
 M_SafePkg7
-package dependencies: array-0.5.2.0 base-4.11.0.0* bytestring-0.10.8.2* deepseq-1.4.3.0 ghc-prim-0.5.2.0 integer-gmp-1.0.1.0
+package dependencies: array-0.5.1.0 base-4.9.0.0* bytestring-0.10.7.0* deepseq-1.4.2.0 ghc-prim-0.5.0.0 integer-gmp-1.0.0.0
 trusted: safe
 require own pkg trusted: False
 
 M_SafePkg8
-package dependencies: array-0.5.2.0 base-4.11.0.0 bytestring-0.10.8.2* deepseq-1.4.3.0 ghc-prim-0.5.2.0 integer-gmp-1.0.1.0
+package dependencies: array-0.5.1.0 base-4.9.0.0 bytestring-0.10.7.0* deepseq-1.4.2.0 ghc-prim-0.5.0.0 integer-gmp-1.0.0.0
 trusted: trustworthy
 require own pkg trusted: False
 
 Testing setting trust
-ignoring (possibly broken) abi-depends field for packages
 trusted: True
-ignoring (possibly broken) abi-depends field for packages
 trusted: False
-ignoring (possibly broken) abi-depends field for packages
 trusted: False
diff --git a/testsuite/tests/typecheck/T13168/T13168.stdout b/testsuite/tests/typecheck/T13168/T13168.stdout
index 32eec3e002..a935d2ffb3 100644
--- a/testsuite/tests/typecheck/T13168/T13168.stdout
+++ b/testsuite/tests/typecheck/T13168/T13168.stdout
@@ -1,3 +1 @@
-ignoring (possibly broken) abi-depends field for packages
-ignoring (possibly broken) abi-depends field for packages
 Window
diff --git a/utils/ghc-pkg/Main.hs b/utils/ghc-pkg/Main.hs
index b2efbb87c4..a32252139f 100644
--- a/utils/ghc-pkg/Main.hs
+++ b/utils/ghc-pkg/Main.hs
@@ -1211,18 +1211,7 @@ updateDBCache verbosity db = do
       pkgsCabalFormat = packages db
 
       pkgsGhcCacheFormat :: [PackageCacheFormat]
-      pkgsGhcCacheFormat
-        = map (recomputeValidAbiDeps pkgsCabalFormat) -- Note [Recompute abi-depends]
-        $ map convertPackageInfoToCacheFormat
-          pkgsCabalFormat
-
-      hasAnyAbiDepends :: InstalledPackageInfo -> Bool
-      hasAnyAbiDepends x = length (abiDepends x) > 0
-
-  -- warn when we find any (possibly-)bogus abi-depends fields;
-  -- Note [Recompute abi-depends]
-  when (any hasAnyAbiDepends pkgsCabalFormat) $
-      infoLn "ignoring (possibly broken) abi-depends field for packages"
+      pkgsGhcCacheFormat = map convertPackageInfoToCacheFormat pkgsCabalFormat
 
   when (verbosity > Normal) $
       infoLn ("writing cache " ++ filename)
@@ -1245,45 +1234,6 @@ type PackageCacheFormat = GhcPkg.InstalledPackageInfo
                             ModuleName
                             OpenModule
 
-{- Note [Recompute abi-depends]
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-Like most fields, `ghc-pkg` relies on who-ever is performing package
-registration to fill in fields; this includes the `abi-depends` field present
-for the package.
-
-However, this was likely a mistake, and is not very robust; in certain cases,
-versions of Cabal may use bogus abi-depends fields for a package when doing
-builds. Why? Because package database information is aggressively cached; it is
-possible to work Cabal into a situation where it uses a cached version of
-`abi-depends`, rather than the one in the actual database after it has been
-recomputed.
-
-However, there is an easy fix: ghc-pkg /already/ knows the `abi-depends` of a
-package, because they are the ABIs of the packages pointed at by the `depends`
-field. So it can simply look up the abi from the dependencies in the original
-database, and ignore whatever the system registering gave it.
-
-So, instead, we do two things here:
-
-  - We throw away the information for a registered package's `abi-depends` field.
-
-  - We recompute it: we simply look up the unit ID of the package in the original
-    database, and use *its* abi-depends.
-
-See Trac #14381, and Cabal issue #4728.
-
--}
-
-recomputeValidAbiDeps :: [InstalledPackageInfo] -> PackageCacheFormat -> PackageCacheFormat
-recomputeValidAbiDeps db pkg = pkg { GhcPkg.abiDepends = catMaybes (newAbiDeps) }
-  where
-    newAbiDeps = flip map (GhcPkg.abiDepends pkg) $ \(k, _) ->
-      case filter (\d -> installedUnitId d == k) db of
-        []  -> Nothing
-        [x] -> Just (k, unAbiHash (abiHash x))
-        _   -> Nothing -- ???
-
 convertPackageInfoToCacheFormat :: InstalledPackageInfo -> PackageCacheFormat
 convertPackageInfoToCacheFormat pkg =
     GhcPkg.InstalledPackageInfo {