ghc-8.4.1: un-revert "update to 8.4.1-alpha2"

This commit undoes the revert from a74b0e717d9156c61264e15a1e7fed680a5e4b31.
See https://github.com/NixOS/nixpkgs/issues/34229 and
https://github.com/NixOS/nixpkgs/pull/34232 for further details about why this
build seemed broken.

+3 -3
+3 -3
pkgs/development/compilers/ghc/8.4.1.nix
··· 24 # platform). Static libs are always built. 25 enableShared ? true 26 27 - , version ? "8.4.20180115" 28 }: 29 30 assert !enableIntegerSimple -> gmp != null; ··· 73 74 src = fetchgit { 75 url = "git://git.haskell.org/ghc.git"; 76 - rev = "3e3a096885c0fcd0703edbeffb4e47f5cbd8f4cc"; 77 - sha256 = "06slymbsd7vsfp4hh40v7cxf7nmp0kvlni2wfq7ag5wlqh04slgs"; 78 }; 79 80 enableParallelBuilding = true;
··· 24 # platform). Static libs are always built. 25 enableShared ? true 26 27 + , version ? "8.4.20180122" 28 }: 29 30 assert !enableIntegerSimple -> gmp != null; ··· 73 74 src = fetchgit { 75 url = "git://git.haskell.org/ghc.git"; 76 + rev = "61db0b8941cfb7ed8941ed29bdb04bd8ef3b71a5"; 77 + sha256 = "15sbpgkal4854jc1xn3sprvpnxwdj0fyy43y5am0h9vja3pjhjyi"; 78 }; 79 80 enableParallelBuilding = true;