--- a/bootstrap	Fri May 14 08:12:42 2021 -0700
+++ b/bootstrap	Fri May 14 12:51:17 2021 -0400
@@ -1,6 +1,6 @@
 #! /bin/sh
 # Print a version string.
-scriptversion=2021-01-10.00; # UTC
+scriptversion=2021-04-11.09; # UTC
 
 # Bootstrap this package from checked-out sources.
 
@@ -115,6 +115,12 @@
 EOF
 }
 
+copyright_year=`echo "$scriptversion" | sed -e 's/[^0-9].*//'`
+copyright="Copyright (C) ${copyright_year} Free Software Foundation, Inc.
+License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
+This is free software: you are free to change and redistribute it.
+There is NO WARRANTY, to the extent permitted by law."
+
 # warnf_ FORMAT-STRING ARG1...
 warnf_ ()
 {
@@ -337,6 +343,12 @@
   --help)
     usage
     exit;;
+  --version)
+    set -e
+    echo "bootstrap $scriptversion"
+    echo "$copyright"
+    exit 0
+    ;;
   --gnulib-srcdir=*)
     GNULIB_SRCDIR=${option#--gnulib-srcdir=};;
   --skip-po)
@@ -686,16 +698,12 @@
       git clone $shallow ${GNULIB_URL:-$default_gnulib_url} "$gnulib_path" \
         || cleanup_gnulib
 
+      trap - 1 2 13 15
+
     elif test -n "$GNULIB_REVISION" \
          && ! git --git-dir="$gnulib_path"/.git cat-file \
               commit "$GNULIB_REVISION"; then
-      # This is a local change in GNU Octave to allow automatic updates.
-      # This change has not (yet) been accepted upstream. Manually merge it
-      # when updating gnulib.
-      # See: https://lists.gnu.org/archive/html/bug-gnulib/2020-08/msg00150.html
       git --git-dir="$gnulib_path"/.git fetch
-
-      trap - 1 2 13 15
     fi
     GNULIB_SRCDIR=$gnulib_path
     ;;
@@ -730,6 +738,10 @@
 
   if test -d "$GNULIB_SRCDIR"/.git && test -n "$GNULIB_REVISION" \
      && ! git_modules_config submodule.gnulib.url >/dev/null; then
+    if ! git --git-dir="$GNULIB_SRCDIR"/.git cat-file \
+         commit "$GNULIB_REVISION"; then
+      git --git-dir="$GNULIB_SRCDIR"/.git fetch
+    fi
     (cd "$GNULIB_SRCDIR" && git checkout "$GNULIB_REVISION") || cleanup_gnulib
   fi
 

--- a/bootstrap.conf	Fri May 14 08:12:42 2021 -0700
+++ b/bootstrap.conf	Fri May 14 12:51:17 2021 -0400
@@ -188,15 +188,18 @@
 source_base="libgnu"
 
 # Go to https://git.savannah.gnu.org/cgit/gnulib.git to find out the latest
-# revision ID.  Paste it below and run
+# revision ID.  Paste it below and then run
 #
 #   ./bootstrap --bootstrap-sync
+#
+# to update the ./bootstrap file from the selected gnulib revision,
+# followed by
+#
 #   patch -p1 -u < ./build-aux/gnulib-bootstrap-git-fetch.diff
 #
-# To update the ./bootstrap file with that from ./gnulib/build-aux/bootstrap
-# and apply local changes.
+# to apply local changes from build-aux/gnulib-bootstrap-git-fetch.diff
 
-: ${GNULIB_REVISION=372b1f317894d6916a94cd3fd08361fe270206b2}
+: ${GNULIB_REVISION=57e8c5005244df16e681428986c3bf0426050814}
 
 # Don't check for translations since we don't have any in Octave yet.
 # This avoids the need for sha1sum or compatible utility in bootstrap.