diff --git a/pkgs/by-name/gg/ggz_base_libs/package.nix b/pkgs/by-name/gg/ggz_base_libs/package.nix
index c786301280d5..3defb98d7796 100644
--- a/pkgs/by-name/gg/ggz_base_libs/package.nix
+++ b/pkgs/by-name/gg/ggz_base_libs/package.nix
@@ -14,9 +14,15 @@ stdenv.mkDerivation (finalAttrs: {
 
   src = fetchurl {
     url = "https://mirrors.ibiblio.org/pub/mirrors/ggzgamingzone/ggz/snapshots/ggz-base-libs-snapshot-${finalAttrs.version}.tar.gz";
-    sha256 = "1cw1vg0fbj36zyggnzidx9cbjwfc1yr4zqmsipxnvns7xa2awbdk";
+    hash = "sha256-sy2uhOpH2237jbriT7IPzHG5WOotfvue/2bI5cDbgbM=";
   };
 
+  postPatch = ''
+    substituteInPlace configure \
+      --replace-fail "/usr/local/ssl/include" "${openssl.dev}/include" \
+      --replace-fail "/usr/local/ssl/lib" "${lib.getLib openssl}/lib"
+  '';
+
   nativeBuildInputs = [ intltool ];
   buildInputs = [
     openssl
@@ -24,11 +30,11 @@ stdenv.mkDerivation (finalAttrs: {
     libgcrypt
   ];
 
-  patchPhase = ''
-    substituteInPlace configure \
-      --replace "/usr/local/ssl/include" "${openssl.dev}/include" \
-      --replace "/usr/local/ssl/lib" "${lib.getLib openssl}/lib"
-  '';
+  # gcc 15 errors on incompatible-pointer-types (ggz_tls_openssl.c OPENSSL_sk_* casts) and implicit-function-declaration (configure C99 VLA probe).
+  env.NIX_CFLAGS_COMPILE = toString [
+    "-Wno-error=incompatible-pointer-types"
+    "-Wno-error=implicit-function-declaration"
+  ];
 
   configureFlags = [
     "--with-tls"