diff --git a/pkgs/by-name/os/osmctools/package.nix b/pkgs/by-name/os/osmctools/package.nix
index c40175e388ae..116f0fdfbfe4 100644
--- a/pkgs/by-name/os/osmctools/package.nix
+++ b/pkgs/by-name/os/osmctools/package.nix
@@ -20,6 +20,9 @@ stdenv.mkDerivation rec {
   nativeBuildInputs = [ autoreconfHook ];
   buildInputs = [ zlib ];
 
+  # Fix build with gcc15 (-std=gnu23)
+  env.NIX_CFLAGS_COMPILE = lib.optionalString stdenv.cc.isGNU "-std=gnu17";
+
   meta = {
     description = "Command line tools for transforming Open Street Map files";
     homepage = [