diff --git a/libc/include/grp.h b/libc/include/grp.h
index fc4d520..ab90022 100644
--- a/libc/include/grp.h
+++ b/libc/include/grp.h
@@ -54,9 +54,9 @@
 struct group	*getgrgid(gid_t);
 struct group	*getgrnam(const char *);
 #if __POSIX_VISIBLE >= 200112 || __XPG_VISIBLE
-struct group	*getgrent(void);
-void		 setgrent(void);
-void		 endgrent(void);
+struct group	*getgrent(void) __errorattr("This function is meaningless on Android.");
+__errordecl(setgrent, "This function is meaningless on Android.");
+__errordecl(endgrent, "This function is meaningless on Android.");
 int		 getgrgid_r(gid_t, struct group *, char *,
 		    size_t, struct group **);
 int		 getgrnam_r(const char *, struct group *, char *,
diff --git a/libc/include/sys/cdefs.h b/libc/include/sys/cdefs.h
index 48763d7..1d33895 100644
--- a/libc/include/sys/cdefs.h
+++ b/libc/include/sys/cdefs.h
@@ -335,13 +335,15 @@
 #endif
 
 #if __GNUC_PREREQ(4, 3)
-#define __errordecl(name, msg) extern void name(void) __attribute__((__error__(msg)))
+#define __errorattr(msg) __attribute__((__error__(msg)))
 #define __warnattr(msg) __attribute__((__warning__(msg)))
 #else
-#define __errordecl(name, msg) extern void name(void)
+#define __errorattr(msg)
 #define __warnattr(msg)
 #endif
 
+#define __errordecl(name, msg) extern void name(void) __errorattr(msg)
+
 /*
  * Some BSD source needs these macros.
  * Originally they embedded the rcs versions of each source file