diff --git a/sys/compat/linuxkpi/common/include/linux/stddef.h b/sys/compat/linuxkpi/common/include/linux/stddef.h
new file mode 100644
index 000000000000..a3bc6b13765e
--- /dev/null
+++ b/sys/compat/linuxkpi/common/include/linux/stddef.h
@@ -0,0 +1,15 @@
+/* Public domain */
+
+#ifndef _LINUXKPI_LINUX_STDDEF_H_
+#define	_LINUXKPI_LINUX_STDDEF_H_
+
+#include <sys/stddef.h>
+
+#define	struct_group(NAME, ...)						\
+    union {								\
+	struct { __VA_ARGS__ };						\
+	struct { __VA_ARGS__ } NAME;					\
+    }
+
+#endif	/* _LINUXKPI_LINUX_STDDEF_H_ */
+