diff --git a/pkgs/build-support/bintools-wrapper/default.nix b/pkgs/build-support/bintools-wrapper/default.nix
index 6e33f6189a4a..86b7e8d7af9a 100644
--- a/pkgs/build-support/bintools-wrapper/default.nix
+++ b/pkgs/build-support/bintools-wrapper/default.nix
@@ -100,7 +100,7 @@ in
 stdenv.mkDerivation {
   pname = targetPrefix
     + (if name != "" then name else "${bintoolsName}-wrapper");
-  version = if bintools == null then null else bintoolsVersion;
+  version = if bintools == null then "" else bintoolsVersion;
 
   preferLocalBuild = true;
 
diff --git a/pkgs/build-support/cc-wrapper/default.nix b/pkgs/build-support/cc-wrapper/default.nix
index c614fe0d287a..388e006a88f9 100644
--- a/pkgs/build-support/cc-wrapper/default.nix
+++ b/pkgs/build-support/cc-wrapper/default.nix
@@ -126,7 +126,7 @@ assert nativePrefix == bintools.nativePrefix;
 stdenv.mkDerivation {
   pname = targetPrefix
     + (if name != "" then name else "${ccName}-wrapper");
-  version = if cc == null then null else ccVersion;
+  version = if cc == null then "" else ccVersion;
 
   preferLocalBuild = true;