diff --git a/src/buffer.c b/src/buffer.c
index 51be9e1a..a48547d6 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -1815,7 +1815,7 @@ simple_flush_read (void)
 
 /* Simple flush write (no multi-volume or label extensions) */
 static void
-simple_flush_write (MAYBE_UNUSED idx_t level)
+simple_flush_write (idx_t UNNAMED (level))
 {
   idx_t status = _flush_write ();
   if (status != record_size)
diff --git a/src/compare.c b/src/compare.c
index 40c9b4dc..59b094b8 100644
--- a/src/compare.c
+++ b/src/compare.c
@@ -78,7 +78,7 @@ report_difference (struct tar_stat_info *st, const char *fmt, ...)
 
 /* Take a buffer returned by read_and_process and do nothing with it.  */
 static bool
-process_noop (MAYBE_UNUSED idx_t size, MAYBE_UNUSED char *data)
+process_noop (idx_t UNNAMED (size), char *UNNAMED (data))
 {
   return true;
 }
diff --git a/src/exclist.c b/src/exclist.c
index ab2dd0e0..eee27416 100644
--- a/src/exclist.c
+++ b/src/exclist.c
@@ -188,7 +188,7 @@ excluded_name (char const *name, struct tar_stat_info *st)
 
 static void
 cvs_addfn (struct exclude *ex, char const *pattern, int options,
-	   MAYBE_UNUSED void *data)
+	   void *UNNAMED (data))
 {
   struct wordsplit ws;
 
@@ -204,7 +204,7 @@ cvs_addfn (struct exclude *ex, char const *pattern, int options,
 
 static void
 git_addfn (struct exclude *ex, char const *pattern, int options,
-	   MAYBE_UNUSED void *data)
+	   void *UNNAMED (data))
 {
   while (c_isspace (*pattern))
     ++pattern;
@@ -217,7 +217,7 @@ git_addfn (struct exclude *ex, char const *pattern, int options,
 
 static void
 bzr_addfn (struct exclude *ex, char const *pattern, int options,
-	   MAYBE_UNUSED void *data)
+	   void *UNNAMED (data))
 {
   while (c_isspace (*pattern))
     ++pattern;
diff --git a/src/extract.c b/src/extract.c
index f9623a45..dab1f328 100644
--- a/src/extract.c
+++ b/src/extract.c
@@ -1564,7 +1564,7 @@ create_placeholder_file (char *file_name, bool is_symlink, bool *interdir_made)
 }
 
 static bool
-extract_link (char *file_name, MAYBE_UNUSED char typeflag)
+extract_link (char *file_name, char UNNAMED (typeflag))
 {
   bool interdir_made = false;
   char const *link_name;
@@ -1639,7 +1639,7 @@ extract_link (char *file_name, MAYBE_UNUSED char typeflag)
 }
 
 static bool
-extract_symlink (char *file_name, MAYBE_UNUSED char typeflag)
+extract_symlink (char *file_name, char typeflag)
 {
   bool interdir_made = false;
 
diff --git a/src/sparse.c b/src/sparse.c
index 6c41f96b..a8f2b23e 100644
--- a/src/sparse.c
+++ b/src/sparse.c
@@ -741,7 +741,7 @@ enum oldgnu_add_status
   };
 
 static bool
-oldgnu_sparse_member_p (MAYBE_UNUSED struct tar_sparse_file *file)
+oldgnu_sparse_member_p (struct tar_sparse_file *UNNAMED (file))
 {
   return current_header->header.typeflag == GNUTYPE_SPARSE;
 }
@@ -883,7 +883,7 @@ static struct tar_sparse_optab const oldgnu_optab = {
 /* Star */
 
 static bool
-star_sparse_member_p (MAYBE_UNUSED struct tar_sparse_file *file)
+star_sparse_member_p (struct tar_sparse_file *UNNAMED (file))
 {
   return current_header->header.typeflag == GNUTYPE_SPARSE;
 }
diff --git a/src/tar.c b/src/tar.c
index 9376b59b..1ee5ed41 100644
--- a/src/tar.c
+++ b/src/tar.c
@@ -1210,7 +1210,7 @@ report_textual_dates (struct tar_args *args)
 
 
 static char *
-tar_help_filter (int key, const char *text, MAYBE_UNUSED void *input)
+tar_help_filter (int key, const char *text, void *UNNAMED (input))
 {
   struct obstack stk;
   char *s;
diff --git a/src/xheader.c b/src/xheader.c
index 4dddc536..05f905ed 100644
--- a/src/xheader.c
+++ b/src/xheader.c
@@ -719,8 +719,7 @@ xheader_decode (struct tar_stat_info *st)
 }
 
 static void
-decg (void *data, char const *keyword, char const *value,
-      MAYBE_UNUSED idx_t size)
+decg (void *data, char const *keyword, char const *value, idx_t size)
 {
   struct keyword_list **kwl = data;
   struct xhdr_tab const *tab = locate_handler (keyword);
@@ -1090,24 +1089,24 @@ decode_num (uintmax_t *num, char const *arg, uintmax_t maxval,
 }
 
 static void
-dummy_coder (MAYBE_UNUSED struct tar_stat_info const *st,
-	     MAYBE_UNUSED char const *keyword,
-	     MAYBE_UNUSED struct xheader *xhdr,
-	     MAYBE_UNUSED void const *data)
+dummy_coder (struct tar_stat_info const *UNNAMED (st),
+	     char const *UNNAMED (keyword),
+	     struct xheader *UNNAMED (xhdr),
+	     void const *UNNAMED (data))
 {
 }
 
 static void
-dummy_decoder (MAYBE_UNUSED struct tar_stat_info *st,
-	       MAYBE_UNUSED char const *keyword,
-	       MAYBE_UNUSED char const *arg,
-	       MAYBE_UNUSED idx_t size)
+dummy_decoder (struct tar_stat_info *UNNAMED (st),
+	       char const *UNNAMED (keyword),
+	       char const *UNNAMED (arg),
+	       idx_t UNNAMED (size))
 {
 }
 
 static void
 atime_coder (struct tar_stat_info const *st, char const *keyword,
-	     struct xheader *xhdr, MAYBE_UNUSED void const *data)
+	     struct xheader *xhdr, void const *UNNAMED (data))
 {
   code_time (st->atime, keyword, xhdr);
 }
@@ -1116,7 +1115,7 @@ static void
 atime_decoder (struct tar_stat_info *st,
 	       char const *keyword,
 	       char const *arg,
-	       MAYBE_UNUSED idx_t size)
+	       idx_t UNNAMED (size))
 {
   struct timespec ts;
   if (decode_time (&ts, arg, keyword))
@@ -1125,7 +1124,7 @@ atime_decoder (struct tar_stat_info *st,
 
 static void
 gid_coder (struct tar_stat_info const *st, char const *keyword,
-	   struct xheader *xhdr, MAYBE_UNUSED void const *data)
+	   struct xheader *xhdr, void const *UNNAMED (data))
 {
   code_signed_num (st->stat.st_gid, keyword,
 		   TYPE_MINIMUM (gid_t), TYPE_MAXIMUM (gid_t), xhdr);
@@ -1135,7 +1134,7 @@ static void
 gid_decoder (struct tar_stat_info *st,
 	     char const *keyword,
 	     char const *arg,
-	     MAYBE_UNUSED idx_t size)
+	     idx_t UNNAMED (size))
 {
   intmax_t u;
   if (decode_signed_num (&u, arg, TYPE_MINIMUM (gid_t),
@@ -1145,39 +1144,39 @@ gid_decoder (struct tar_stat_info *st,
 
 static void
 gname_coder (struct tar_stat_info const *st, char const *keyword,
-	     struct xheader *xhdr, MAYBE_UNUSED void const *data)
+	     struct xheader *xhdr, void const *UNNAMED (data))
 {
   code_string (st->gname, keyword, xhdr);
 }
 
 static void
 gname_decoder (struct tar_stat_info *st,
-	       MAYBE_UNUSED char const *keyword,
+	       char const *UNNAMED (keyword),
 	       char const *arg,
-	       MAYBE_UNUSED idx_t size)
+	       idx_t UNNAMED (size))
 {
   decode_string (&st->gname, arg);
 }
 
 static void
 linkpath_coder (struct tar_stat_info const *st, char const *keyword,
-		struct xheader *xhdr, MAYBE_UNUSED void const *data)
+		struct xheader *xhdr, void const *UNNAMED (data))
 {
   code_string (st->link_name, keyword, xhdr);
 }
 
 static void
 linkpath_decoder (struct tar_stat_info *st,
-		  MAYBE_UNUSED char const *keyword,
+		  char const *UNNAMED (keyword),
 		  char const *arg,
-		  MAYBE_UNUSED idx_t size)
+		  idx_t UNNAMED (size))
 {
   decode_string (&st->link_name, arg);
 }
 
 static void
 ctime_coder (struct tar_stat_info const *st, char const *keyword,
-	     struct xheader *xhdr, MAYBE_UNUSED void const *data)
+	     struct xheader *xhdr, void const *UNNAMED (data))
 {
   code_time (st->ctime, keyword, xhdr);
 }
@@ -1186,7 +1185,7 @@ static void
 ctime_decoder (struct tar_stat_info *st,
 	       char const *keyword,
 	       char const *arg,
-	       MAYBE_UNUSED idx_t size)
+	       idx_t UNNAMED (size))
 {
   struct timespec ts;
   if (decode_time (&ts, arg, keyword))
@@ -1205,7 +1204,7 @@ static void
 mtime_decoder (struct tar_stat_info *st,
 	       char const *keyword,
 	       char const *arg,
-	       MAYBE_UNUSED idx_t size)
+	       idx_t UNNAMED (size))
 {
   struct timespec ts;
   if (decode_time (&ts, arg, keyword))
@@ -1214,7 +1213,7 @@ mtime_decoder (struct tar_stat_info *st,
 
 static void
 path_coder (struct tar_stat_info const *st, char const *keyword,
-	    struct xheader *xhdr, MAYBE_UNUSED void const *data)
+	    struct xheader *xhdr, void const *UNNAMED (data))
 {
   code_string (st->file_name, keyword, xhdr);
 }
@@ -1233,9 +1232,9 @@ raw_path_decoder (struct tar_stat_info *st, char const *arg)
 
 static void
 path_decoder (struct tar_stat_info *st,
-	      MAYBE_UNUSED char const *keyword,
+	      char const *UNNAMED (keyword),
 	      char const *arg,
-	      MAYBE_UNUSED idx_t size)
+	      idx_t UNNAMED (size))
 {
   if (! st->sparse_name_done)
     raw_path_decoder (st, arg);
@@ -1243,9 +1242,9 @@ path_decoder (struct tar_stat_info *st,
 
 static void
 sparse_path_decoder (struct tar_stat_info *st,
-		     MAYBE_UNUSED char const *keyword,
+		     char const *UNNAMED (keyword),
                      char const *arg,
-		     MAYBE_UNUSED idx_t size)
+		     idx_t UNNAMED (size))
 {
   st->sparse_name_done = true;
   raw_path_decoder (st, arg);
@@ -1253,7 +1252,7 @@ sparse_path_decoder (struct tar_stat_info *st,
 
 static void
 size_coder (struct tar_stat_info const *st, char const *keyword,
-	    struct xheader *xhdr, MAYBE_UNUSED void const *data)
+	    struct xheader *xhdr, void const *UNNAMED (data))
 {
   code_num (st->stat.st_size, keyword, xhdr);
 }
@@ -1262,7 +1261,7 @@ static void
 size_decoder (struct tar_stat_info *st,
 	      char const *keyword,
 	      char const *arg,
-	      MAYBE_UNUSED idx_t size)
+	      idx_t UNNAMED (size))
 {
   uintmax_t u;
   if (decode_num (&u, arg, TYPE_MAXIMUM (off_t), keyword))
@@ -1271,7 +1270,7 @@ size_decoder (struct tar_stat_info *st,
 
 static void
 uid_coder (struct tar_stat_info const *st, char const *keyword,
-	   struct xheader *xhdr, MAYBE_UNUSED void const *data)
+	   struct xheader *xhdr, void const *UNNAMED (data))
 {
   code_signed_num (st->stat.st_uid, keyword,
 		   TYPE_MINIMUM (uid_t), TYPE_MAXIMUM (uid_t), xhdr);
@@ -1281,7 +1280,7 @@ static void
 uid_decoder (struct tar_stat_info *st,
 	     char const *keyword,
 	     char const *arg,
-	     MAYBE_UNUSED idx_t size)
+	     idx_t UNNAMED (size))
 {
   intmax_t u;
   if (decode_signed_num (&u, arg, TYPE_MINIMUM (uid_t),
@@ -1291,16 +1290,16 @@ uid_decoder (struct tar_stat_info *st,
 
 static void
 uname_coder (struct tar_stat_info const *st, char const *keyword,
-	     struct xheader *xhdr, MAYBE_UNUSED void const *data)
+	     struct xheader *xhdr, void const *UNNAMED (data))
 {
   code_string (st->uname, keyword, xhdr);
 }
 
 static void
 uname_decoder (struct tar_stat_info *st,
-	       MAYBE_UNUSED char const *keyword,
+	       char const *UNNAMED (keyword),
 	       char const *arg,
-	       MAYBE_UNUSED idx_t size)
+	       idx_t UNNAMED (size))
 {
   decode_string (&st->uname, arg);
 }
@@ -1316,7 +1315,7 @@ static void
 sparse_size_decoder (struct tar_stat_info *st,
 		     char const *keyword,
 		     char const *arg,
-		     MAYBE_UNUSED idx_t size)
+		     idx_t UNNAMED (size))
 {
   uintmax_t u;
   if (decode_num (&u, arg, TYPE_MAXIMUM (off_t), keyword))
@@ -1329,7 +1328,7 @@ sparse_size_decoder (struct tar_stat_info *st,
 static void
 sparse_numblocks_coder (struct tar_stat_info const *st, char const *keyword,
 			struct xheader *xhdr,
-			MAYBE_UNUSED void const *data)
+			void const *UNNAMED (data))
 {
   code_num (st->sparse_map_avail, keyword, xhdr);
 }
@@ -1338,7 +1337,7 @@ static void
 sparse_numblocks_decoder (struct tar_stat_info *st,
 			  char const *keyword,
 			  char const *arg,
-			  MAYBE_UNUSED idx_t size)
+			  idx_t UNNAMED (size))
 {
   uintmax_t u;
   if (decode_num (&u, arg, SIZE_MAX, keyword))
@@ -1361,7 +1360,7 @@ static void
 sparse_offset_decoder (struct tar_stat_info *st,
 		       char const *keyword,
 		       char const *arg,
-		       MAYBE_UNUSED idx_t size)
+		       idx_t UNNAMED (size))
 {
   uintmax_t u;
   if (decode_num (&u, arg, TYPE_MAXIMUM (off_t), keyword))
@@ -1386,7 +1385,7 @@ static void
 sparse_numbytes_decoder (struct tar_stat_info *st,
 			 char const *keyword,
 			 char const *arg,
-			 MAYBE_UNUSED idx_t size)
+			 idx_t UNNAMED (size))
 {
   uintmax_t u;
   if (decode_num (&u, arg, TYPE_MAXIMUM (off_t), keyword))
@@ -1403,7 +1402,7 @@ static void
 sparse_map_decoder (struct tar_stat_info *st,
 		    char const *keyword,
 		    char const *arg,
-		    MAYBE_UNUSED idx_t size)
+		    idx_t UNNAMED (size))
 {
   bool offset = true;
   struct sp_array e;
@@ -1472,7 +1471,7 @@ sparse_map_decoder (struct tar_stat_info *st,
 }
 
 static void
-dumpdir_coder (MAYBE_UNUSED struct tar_stat_info const *st, char const *keyword,
+dumpdir_coder (struct tar_stat_info const *UNNAMED (st), char const *keyword,
 	       struct xheader *xhdr, void const *data)
 {
   xheader_print_n (xhdr, keyword, data, dumpdir_size (data));
@@ -1480,7 +1479,7 @@ dumpdir_coder (MAYBE_UNUSED struct tar_stat_info const *st, char const *keyword,
 
 static void
 dumpdir_decoder (struct tar_stat_info *st,
-		 MAYBE_UNUSED char const *keyword,
+		 char const *UNNAMED (keyword),
 		 char const *arg,
 		 idx_t size)
 {
@@ -1489,7 +1488,7 @@ dumpdir_decoder (struct tar_stat_info *st,
 }
 
 static void
-volume_label_coder (MAYBE_UNUSED struct tar_stat_info const *st,
+volume_label_coder (struct tar_stat_info const *UNNAMED (st),
 		    char const *keyword,
 		    struct xheader *xhdr, void const *data)
 {
@@ -1497,16 +1496,16 @@ volume_label_coder (MAYBE_UNUSED struct tar_stat_info const *st,
 }
 
 static void
-volume_label_decoder (MAYBE_UNUSED struct tar_stat_info *st,
-		      MAYBE_UNUSED char const *keyword,
+volume_label_decoder (struct tar_stat_info *UNNAMED (st),
+		      char const *UNNAMED (keyword),
 		      char const *arg,
-		      MAYBE_UNUSED idx_t size)
+		      idx_t UNNAMED (size))
 {
   decode_string (&volume_label, arg);
 }
 
 static void
-volume_size_coder (MAYBE_UNUSED struct tar_stat_info const *st,
+volume_size_coder (struct tar_stat_info const *UNNAMED (st),
 		   char const *keyword,
 		   struct xheader *xhdr, void const *data)
 {
@@ -1515,9 +1514,9 @@ volume_size_coder (MAYBE_UNUSED struct tar_stat_info const *st,
 }
 
 static void
-volume_size_decoder (MAYBE_UNUSED struct tar_stat_info *st,
+volume_size_decoder (struct tar_stat_info *UNNAMED (st),
 		     char const *keyword,
-		     char const *arg, MAYBE_UNUSED idx_t size)
+		     char const *arg, idx_t UNNAMED (size))
 {
   uintmax_t u;
   if (decode_num (&u, arg, TYPE_MAXIMUM (off_t), keyword))
@@ -1526,7 +1525,7 @@ volume_size_decoder (MAYBE_UNUSED struct tar_stat_info *st,
 
 /* FIXME: Merge with volume_size_coder */
 static void
-volume_offset_coder (MAYBE_UNUSED struct tar_stat_info const *st,
+volume_offset_coder (struct tar_stat_info const *UNNAMED (st),
 		     char const *keyword,
 		     struct xheader *xhdr, void const *data)
 {
@@ -1535,9 +1534,9 @@ volume_offset_coder (MAYBE_UNUSED struct tar_stat_info const *st,
 }
 
 static void
-volume_offset_decoder (MAYBE_UNUSED struct tar_stat_info *st,
+volume_offset_decoder (struct tar_stat_info *UNNAMED (st),
 		       char const *keyword,
-		       char const *arg, MAYBE_UNUSED idx_t size)
+		       char const *arg, idx_t UNNAMED (size))
 {
   uintmax_t u;
   if (decode_num (&u, arg, TYPE_MAXIMUM (off_t), keyword))
@@ -1545,39 +1544,39 @@ volume_offset_decoder (MAYBE_UNUSED struct tar_stat_info *st,
 }
 
 static void
-volume_filename_decoder (MAYBE_UNUSED struct tar_stat_info *st,
-			 MAYBE_UNUSED char const *keyword,
+volume_filename_decoder (struct tar_stat_info *UNNAMED (st),
+			 char const *UNNAMED (keyword),
 			 char const *arg,
-			 MAYBE_UNUSED idx_t size)
+			 idx_t UNNAMED (size))
 {
   decode_string (&continued_file_name, arg);
 }
 
 static void
 xattr_selinux_coder (struct tar_stat_info const *st, char const *keyword,
-		     struct xheader *xhdr, MAYBE_UNUSED void const *data)
+		     struct xheader *xhdr, void const *UNNAMED (data))
 {
   code_string (st->cntx_name, keyword, xhdr);
 }
 
 static void
 xattr_selinux_decoder (struct tar_stat_info *st,
-		       MAYBE_UNUSED char const *keyword, char const *arg,
-		       MAYBE_UNUSED idx_t size)
+		       char const *UNNAMED (keyword), char const *arg,
+		       idx_t UNNAMED (size))
 {
   decode_string (&st->cntx_name, arg);
 }
 
 static void
 xattr_acls_a_coder (struct tar_stat_info const *st , char const *keyword,
-		    struct xheader *xhdr, MAYBE_UNUSED void const *data)
+		    struct xheader *xhdr, void const *UNNAMED (data))
 {
   xheader_print_n (xhdr, keyword, st->acls_a_ptr, st->acls_a_len);
 }
 
 static void
 xattr_acls_a_decoder (struct tar_stat_info *st,
-		      MAYBE_UNUSED char const *keyword,
+		      char const *UNNAMED (keyword),
 		      char const *arg, idx_t size)
 {
   st->acls_a_ptr = xmemdup (arg, size + 1);
@@ -1586,14 +1585,14 @@ xattr_acls_a_decoder (struct tar_stat_info *st,
 
 static void
 xattr_acls_d_coder (struct tar_stat_info const *st , char const *keyword,
-		    struct xheader *xhdr, MAYBE_UNUSED void const *data)
+		    struct xheader *xhdr, void const *UNNAMED (data))
 {
   xheader_print_n (xhdr, keyword, st->acls_d_ptr, st->acls_d_len);
 }
 
 static void
 xattr_acls_d_decoder (struct tar_stat_info *st,
-		      MAYBE_UNUSED char const *keyword, char const *arg,
+		      char const *UNNAMED (keyword), char const *arg,
 		      idx_t size)
 {
   st->acls_d_ptr = xmemdup (arg, size + 1);
@@ -1629,7 +1628,7 @@ xattr_decoder (struct tar_stat_info *st,
 
 static void
 sparse_major_coder (struct tar_stat_info const *st, char const *keyword,
-		    struct xheader *xhdr, MAYBE_UNUSED void const *data)
+		    struct xheader *xhdr, void const *UNNAMED (data))
 {
   code_num (st->sparse_major, keyword, xhdr);
 }
@@ -1638,7 +1637,7 @@ static void
 sparse_major_decoder (struct tar_stat_info *st,
 		      char const *keyword,
 		      char const *arg,
-		      MAYBE_UNUSED idx_t size)
+		      idx_t UNNAMED (size))
 {
   uintmax_t u;
   if (decode_num (&u, arg, INTMAX_MAX, keyword))
@@ -1647,7 +1646,7 @@ sparse_major_decoder (struct tar_stat_info *st,
 
 static void
 sparse_minor_coder (struct tar_stat_info const *st, char const *keyword,
-		    struct xheader *xhdr, MAYBE_UNUSED void const *data)
+		    struct xheader *xhdr, void const *UNNAMED (data))
 {
   code_num (st->sparse_minor, keyword, xhdr);
 }
@@ -1656,7 +1655,7 @@ static void
 sparse_minor_decoder (struct tar_stat_info *st,
 		      char const *keyword,
 		      char const *arg,
-		      MAYBE_UNUSED idx_t size)
+		      idx_t UNNAMED (size))
 {
   uintmax_t u;
   if (decode_num (&u, arg, INTMAX_MAX, keyword))