diff --git a/pkgs/applications/graphics/ImageMagick/default.nix b/pkgs/applications/graphics/ImageMagick/default.nix
index 55b61fb5169d..77e1adeb619b 100644
--- a/pkgs/applications/graphics/ImageMagick/default.nix
+++ b/pkgs/applications/graphics/ImageMagick/default.nix
@@ -47,13 +47,13 @@ in
 
 stdenv.mkDerivation (finalAttrs: {
   pname = "imagemagick";
-  version = "7.1.1-10";
+  version = "7.1.1-11";
 
   src = fetchFromGitHub {
     owner = "ImageMagick";
     repo = "ImageMagick";
     rev = finalAttrs.version;
-    hash = "sha256-W7s/j4R4C22hYVhye8TjDYHtDq/1Q4GGu/9lxyjk6sA=";
+    hash = "sha256-/CZRnNy/p87sEcH94RkRYgYXexFSU0Bm809pcvDFdV4=";
   };
 
   outputs = [ "out" "dev" "doc" ]; # bin/ isn't really big
diff --git a/pkgs/top-level/make-tarball.nix b/pkgs/top-level/make-tarball.nix
index 61ed61192d5c..0d9a89d0e3fa 100644
--- a/pkgs/top-level/make-tarball.nix
+++ b/pkgs/top-level/make-tarball.nix
@@ -19,7 +19,7 @@ pkgs.releaseTools.sourceTarball {
   versionSuffix = "pre${
     if nixpkgs ? lastModified
     then builtins.substring 0 8 (nixpkgs.lastModifiedDate or nixpkgs.lastModified)
-    else toString nixpkgs.revCount}.${nixpkgs.shortRev or "dirty"}";
+    else toString (nixpkgs.revCount or 0)}.${nixpkgs.shortRev or "dirty"}";
 
   buildInputs = with pkgs; [ nix.out jq lib-tests brotli ];