diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 2a08b96dfa4..e5fed46ca37 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -4141,7 +4141,9 @@ let
 
   spin = callPackage ../development/tools/analysis/spin { };
 
-  splint = callPackage ../development/tools/analysis/splint { };
+  splint = callPackage ../development/tools/analysis/splint {
+    flex = flex_2_5_35;
+  };
 
   stm32flash = callPackage ../development/tools/misc/stm32flash { };