eigen: fetch source from gitlab

pkgs/development/libraries/eigen/default.nix

@@ -1,16 +1,14 @@
-{stdenv, fetchurl, cmake}:
+{ stdenv, fetchFromGitLab, cmake }:
 
-let
-  version = "3.3.7";
-in
-stdenv.mkDerivation {
+stdenv.mkDerivation rec {
   pname = "eigen";
-  inherit version;
+  version = "3.3.7";
 
-  src = fetchurl {
-    url = "https://bitbucket.org/eigen/eigen/get/${version}.tar.gz";
-    name = "eigen-${version}.tar.gz";
-    sha256 = "1nnh0v82a5xibcjaph51mx06mxbllk77fvihnd5ba0kpl23yz13y";
+  src = fetchFromGitLab {
+    owner = "libeigen";
+    repo = "eigen";
+    rev = version;
+    sha256 = "1i3cvg8d70dk99fl3lrv3wqhfpdnm5kx01fl7r2bz46sk9bphwm1";
   };
 
   patches = [
@@ -22,7 +20,7 @@ stdenv.mkDerivation {
   meta = with stdenv.lib; {
     description = "C++ template library for linear algebra: vectors, matrices, and related algorithms";
     license = licenses.lgpl3Plus;
-    homepage = http://eigen.tuxfamily.org ;
+    homepage = "https://eigen.tuxfamily.org";
     platforms = platforms.unix;
     maintainers = with stdenv.lib.maintainers; [ sander raskin ];
     inherit version;