Build errors in master branch snapshot

[Neil Jerram]

Apologies for having been mostly offline recently...

I see that since the morning of 1st December, the master branch
snapshot has been failing to build.  Full log can be seen at
http://www.ossau.uklinux.net/guile/snapshots; the errors are as below.

Does this just mean that I need a gnulib update or re-import, or
something?  If so, would it make sense to add something to autogen.sh
to do this?

Regards,
       Neil

=== ./autogen.sh
...
configure:7313: error: possibly undefined macro: gl_SAFE_READ
      If this token and others are legitimate, please use m4_pattern_allow.
      See the Autoconf documentation.
configure:7314: error: possibly undefined macro: gl_SAFE_WRITE
configure:7775: error: possibly undefined macro: gl_UNISTD_H
configure:7897: error: possibly undefined macro: gl_FUNC_WRITE
configure:7898: error: possibly undefined macro: gl_UNISTD_MODULE_INDICATOR
autoreconf: /usr/bin/autoconf failed with exit status: 1

=== ./configure --with-threads
...
./configure: line 7313: gl_SAFE_READ: command not found
./configure: line 7314: gl_SAFE_WRITE: command not found
./configure: line 7315: gt_TYPE_SSIZE_T: command not found
...
./configure: line 7775: gl_UNISTD_H: command not found
...
./configure: line 7897: gl_FUNC_WRITE: command not found
./configure: line 7898: syntax error near unexpected token `write'
./configure: line 7898: `  gl_UNISTD_MODULE_INDICATOR(write)'