Update GCC compiler & friends
gcc used by ghc is now about 1.5 years old. It's going to take some time for a new GHC release as well. Would be good to update gcc too. Probably it's backwards compatible with old gcc so would be easy to patch.
source code also points to other tools of which some have newer versions.
Packages can be browsed here http://repo.msys2.org/mingw/x86_64/