Update .cabal (#182)

* Bump version

* Bump `base` version.

* Add some of the extensions we require.

* Turn off `-feager-blackholing` for GHC 8.2 and above.

* Update changelog

Author: treeowl

CHANGES.md

@@ -1,9 +1,13 @@
-## next
+## 0.2.9.0
 
  * Add `Ord/Ord1/Ord2` instances.
- * Remove support for GHC versions before 7.8. (Thanks, Dmitry Ivanov!)
+
+ * Remove support for GHC versions before 7.8. (Thanks, Dmitry Ivanov)
+
  * Use `SmallArray#` instead of `Array#` for GHC versions 7.10 and above.
-   (Thanks, Dmitry Ivanov!)
+   (Thanks, Dmitry Ivanov)
+
+ * Adjust for `Semigroup => Monoid` proposal implementation.
 
 ## 0.2.8.0
 

unordered-containers.cabal

@@ -1,5 +1,5 @@
 name:           unordered-containers
-version:        0.2.8.0
+version:        0.2.9.0
 synopsis:       Efficient hashing-based container types
 description:
   Efficient hashing-based container types.  The containers have been
@@ -39,15 +39,24 @@ library
     Data.HashMap.UnsafeShift
 
   build-depends:
-    base >= 4 && < 5,
+    base >= 4.7 && < 5,
     deepseq >= 1.1,
     hashable >= 1.0.1.1 && < 1.3
 
+  other-extensions:
+    RoleAnnotations,
+    UnboxedTuples,
+    ScopedTypeVariables,
+    MagicHash,
+    BangPatterns
+
   ghc-options: -Wall -O2 -fwarn-tabs -ferror-spans
-  -- This is absolutely essential for correctness due to the
-  -- referential-transparency-breaking mutability in unsafeInsertWith. See
-  -- #147 and GHC #13615 for details.
-  ghc-options: -feager-blackholing
+
+  if impl (ghc < 8.2)
+    -- This is absolutely necessary (but not sufficient) for correctness due to
+    -- the referential-transparency-breaking mutability in unsafeInsertWith. See
+    -- #147 and GHC #13615 for details. The bug was fixed in GHC 8.2.
+    ghc-options: -feager-blackholing
   if flag(debug)
     cpp-options: -DASSERTS