diff --git a/pkgs/by-name/as/as31/package.nix b/pkgs/by-name/as/as31/package.nix
index 2936f7a79958..d2ba3b530cd1 100644
--- a/pkgs/by-name/as/as31/package.nix
+++ b/pkgs/by-name/as/as31/package.nix
@@ -2,6 +2,7 @@
   lib,
   stdenv,
   fetchurl,
+  fetchpatch,
   bison,
 }:
 
@@ -18,6 +19,12 @@ stdenv.mkDerivation rec {
   patches = [
     # Check return value of getline in run.c
     ./0000-getline-break.patch
+
+    # fix build with gcc14
+    (fetchpatch {
+      url = "https://salsa.debian.org/debian/as31/-/raw/76735fbf1fb00ce70ffd98385137908b7bd9bd5c/debian/patches/update_sizebuf_types.patch";
+      hash = "sha256-ERrPdY0afKwXmdSLoWmWR55nKfvmieGlz+nhwFWRnrM=";
+    })
   ];
 
   postPatch = ''