diff --git a/lib/stat-size.h b/lib/stat-size.h
index 3462ecdbb..8930bb5c5 100644
--- a/lib/stat-size.h
+++ b/lib/stat-size.h
@@ -66,8 +66,7 @@
    st_blocks ((statbuf).st_size) : 0)
 #endif
 #else
-/* Some systems, like Sequents, return st_blksize of 0 on pipes.
-   Also, when running 'rsh hpux11-system cat any-file', cat would
+/* When running 'rsh hpux11-system cat any-file', cat would
    determine that the output stream had an st_blksize of 2147421096.
    Conversely st_blksize can be 2 GiB (or maybe even larger) with XFS
    on 64-bit hosts.  Somewhat arbitrarily, limit the "optimal" block
diff --git a/m4.include/gnulib/fsusage.m4 b/m4.include/gnulib/fsusage.m4
index f6e683de8..ecf1cc57e 100644
--- a/m4.include/gnulib/fsusage.m4
+++ b/m4.include/gnulib/fsusage.m4
@@ -224,7 +224,7 @@ int check_f_blocks_size[sizeof fsd.f_blocks * CHAR_BIT <= 32 ? -1 : 1];
     if test $fu_cv_sys_stat_statfs4 = yes; then
       ac_fsusage_space=yes
       AC_DEFINE([STAT_STATFS4], [1],
-        [Define if statfs takes 4 args.  (SVR3, Dynix, old Irix)])
+        [Define if statfs takes 4 args.  (SVR3, old Irix)])
     fi
   fi
 
diff --git a/m4.include/gnulib/ls-mntd-fs.m4 b/m4.include/gnulib/ls-mntd-fs.m4
index 735b52ff2..e35e5da70 100644
--- a/m4.include/gnulib/ls-mntd-fs.m4
+++ b/m4.include/gnulib/ls-mntd-fs.m4
@@ -19,8 +19,8 @@ dnl
 AC_DEFUN([AC_FUNC_GETMNTENT],
 [
   # getmntent is in the standard C library on UNICOS, in -lsun on Irix 4,
-  # -lseq on Dynix/PTX, -lgen on Unixware.
-  AC_SEARCH_LIBS([getmntent], [sun seq gen])
+  # -lseq on Unixware.
+  AC_SEARCH_LIBS([getmntent], [sun gen])
   AC_CHECK_FUNCS([getmntent])
 ])
 
@@ -120,7 +120,7 @@ yes
     # Determine whether it's the one-argument variant or the two-argument one.
 
     if test -z "$ac_list_mounted_fs"; then
-      # glibc, HP-UX, IRIX, Cygwin, Android, also (obsolete) 4.3BSD, SunOS, Dynix.
+      # glibc, HP-UX, IRIX, Cygwin, Android, also (obsolete) 4.3BSD, SunOS.
       AC_CACHE_CHECK([for one-argument getmntent function],
         [fu_cv_sys_mounted_getmntent1],
         [AC_COMPILE_IFELSE(
@@ -136,9 +136,6 @@ yes
 # if defined MNT_MNTTAB /* HP-UX.  */
 #  define MOUNTED MNT_MNTTAB
 # endif
-# if defined MNTTABNAME /* Dynix.  */
-#  define MOUNTED MNTTABNAME
-# endif
 #endif
 ]],
               [[struct mntent *mnt = 0; char *table = MOUNTED;
@@ -152,7 +149,7 @@ yes
         AC_DEFINE([MOUNTED_GETMNTENT1], [1],
           [Define if there is a function named getmntent for reading the list
            of mounted file systems, and that function takes a single argument.
-           (4.3BSD, SunOS, HP-UX, Dynix, Irix)])
+           (4.3BSD, SunOS, HP-UX, Irix)])
         AC_CHECK_FUNCS([hasmntopt])
       fi
     fi
diff --git a/src/filemanager/mountlist.c b/src/filemanager/mountlist.c
index 8a0e7c679..6f3ed25db 100644
--- a/src/filemanager/mountlist.c
+++ b/src/filemanager/mountlist.c
@@ -80,7 +80,7 @@
 #endif
 
 #ifdef MOUNTED_GETMNTENT1       /* glibc, HP-UX, IRIX, Cygwin, Android,
-                                   also (obsolete) 4.3BSD, SunOS, Dynix */
+                                   also (obsolete) 4.3BSD, SunOS */
 #include <mntent.h>
 #include <sys/types.h>
 #ifndef MOUNTED
@@ -90,9 +90,6 @@
 #ifdef MNT_MNTTAB               /* HP-UX.  */
 #define MOUNTED MNT_MNTTAB
 #endif
-#ifdef MNTTABNAME               /* Dynix.  */
-#define MOUNTED MNTTABNAME
-#endif
 #endif
 #endif
 
@@ -632,7 +629,7 @@ read_file_system_list (void)
 #endif
 
 #ifdef MOUNTED_GETMNTENT1       /* glibc, HP-UX, IRIX, Cygwin, Android,
-                                   also (obsolete) 4.3BSD, SunOS, Dynix */
+                                   also (obsolete) 4.3BSD, SunOS */
     {
         FILE *fp;
 
@@ -1489,11 +1486,7 @@ get_fs_usage (char const *file, char const *disk, struct fs_usage *fsp)
 
         fsp->fsu_blocksize = PROPAGATE_ALL_ONES (fsd.f_fsize);
 
-#elif defined STAT_STATFS4      /* SVR3, Dynix, old Irix */
-
-#if !defined _SEQUENT_
-#define f_bavail f_bfree
-#endif
+#elif defined STAT_STATFS4      /* SVR3, old Irix */
 
         struct statfs fsd;