diff --git a/pkgs/by-name/t4/t4kcommon/package.nix b/pkgs/by-name/t4/t4kcommon/package.nix
index ab98679d6bc2..4a6475884463 100644
--- a/pkgs/by-name/t4/t4kcommon/package.nix
+++ b/pkgs/by-name/t4/t4kcommon/package.nix
@@ -40,7 +40,7 @@ stdenv.mkDerivation (finalAttrs: {
   # gcc-10. Otherwise build fails as:
   #   ld: CMakeFiles/t4k_common.dir/t4k_throttle.c.o:(.bss+0x0): multiple definition of
   #     `wrapped_lines'; CMakeFiles/t4k_common.dir/t4k_audio.c.o:(.bss+0x0): first defined here
-  env.NIX_CFLAGS_COMPILE = "-fcommon -DGNULIB_UNISTR_U8_MBTOUC_UNSAFE -Wno-incompatible-pointer-types";
+  env.NIX_CFLAGS_COMPILE = "-fcommon -DGNULIB_UNISTR_U8_MBTOUC_UNSAFE -Wno-incompatible-pointer-types -std=gnu17";
 
   nativeBuildInputs = [
     cmake