+ 

+ == GHC 8.4

+ 

+ The **Haskell** compiler, GHC, has been upgraded to version 8.4.4 in Fedora 30, up from version 8.2.2 in Fedora 29.

+ Haskell packages have bene upgraded to Stackage LTS 12 versions.

+ 

+ Notable changes include:

+ 

+ * Further refinement of `TypeInType`, including significant improvements in error messages.

+ * Improvements in code generation resulting in noticable performance improvements in some types of programs.

+ * Core library improvements, including phase 2 of the Semigroup/Monoid proposal

+ * Many improvements to instance deriving

+ * The resolution of nearly 300 other tickets for the 8.4.1 major release, and further bugfixes in the subsequent stable minor version releases

+ 

+ For details, see upstream release announcements:

+ 

+ * link:https://downloads.haskell.org/~ghc/8.4.1/docs/html/users_guide/8.4.1-notes.html[8.4.1 release notes]

+ * link:https://downloads.haskell.org/~ghc/8.4.2/docs/html/users_guide/8.4.2-notes.html[8.4.2 release notes]

+ * link:https://downloads.haskell.org/~ghc/8.4.3/docs/html/users_guide/8.4.3-notes.html[8.4.3 release notes]

+ * link:https://downloads.haskell.org/~ghc/8.4.4/docs/html/users_guide/8.4.4-notes.html[8.4.4 release notes]