diff --git a/pkgs/build-support/fetchurl/default.nix b/pkgs/build-support/fetchurl/default.nix
index 3cd64ed1c02f..a7c76737e1ad 100644
--- a/pkgs/build-support/fetchurl/default.nix
+++ b/pkgs/build-support/fetchurl/default.nix
@@ -87,6 +87,7 @@ in
 
 assert builtins.isList urls;
 assert (urls == []) != (url == "");
+assert sha512 != "" -> builtins.compareVersions "1.11" builtins.nixVersion <= 0;
 
 
 let