diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index a49fcec77a81..b64f03511956 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -21729,7 +21729,10 @@ with pkgs;
   gnatcoll-iconv = callPackage ../development/libraries/ada/gnatcoll/bindings.nix { component = "iconv"; };
   gnatcoll-lzma = callPackage ../development/libraries/ada/gnatcoll/bindings.nix { component = "lzma"; };
   gnatcoll-omp = callPackage ../development/libraries/ada/gnatcoll/bindings.nix { component = "omp"; };
-  gnatcoll-python3 = callPackage ../development/libraries/ada/gnatcoll/bindings.nix { component = "python3"; };
+  gnatcoll-python3 = callPackage ../development/libraries/ada/gnatcoll/bindings.nix {
+    component = "python3";
+    python3 = python39;
+  };
   gnatcoll-readline = callPackage ../development/libraries/ada/gnatcoll/bindings.nix { component = "readline"; };
   gnatcoll-syslog = callPackage ../development/libraries/ada/gnatcoll/bindings.nix { component = "syslog"; };
   gnatcoll-zlib = callPackage ../development/libraries/ada/gnatcoll/bindings.nix { component = "zlib"; };