diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 1f7422cb1256..4df6e675d681 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -6206,8 +6206,7 @@ let
 
   gmp4 = callPackage ../development/libraries/gmp/4.3.2.nix { }; # required by older GHC versions
   gmp5 = callPackage ../development/libraries/gmp/5.1.x.nix { };
-  gmp6 = callPackage ../development/libraries/gmp/6.x.nix { };
-  gmp = gmp6;
+  gmp = gmp5;
   gmpxx = appendToName "with-cxx" (gmp.override { cxx = true; });
 
   #GMP ex-satellite, so better keep it near gmp