Include <sys/types.h>, so that this file is self-contained.

lib/group-member.h

@@ -19,6 +19,8 @@
 #ifndef GROUP_MEMBER_H_
 # define GROUP_MEMBER_H_ 1
 
+# include <sys/types.h>
+
 int group_member (gid_t);
 
 #endif /* GROUP_MEMBER_H_ */

lib/makepath.h

@@ -19,6 +19,8 @@
 
 /* Written by David MacKenzie <djm@gnu.ai.mit.edu> and Jim Meyering.  */
 
+#include <sys/types.h>
+
 int make_path (const char *_argpath,
 	       int _mode,
 	       int _parent_mode,