Subversion 1.8.x on Solaris 10 x86

Hi there
Our Solaris 10 x86 build box blew up and I'm attempting to build a new one.
I've got it building 1.9.6 fine but when I attempt anything 1.8.18 or
1.8.17 I get this error:

cd subversion/svn && /bin/bash
/home/jenkins/SVN-Build/subversion-packaging/solaris/subversion-1.8.18/libtool
--tag=CC --silent --mode=link suncc -Werror=unknown-warning-option
-I/opt/WANdisco/include -fast -xO5 -xunroll=20 -L/opt/WANdisco/lib
-R/opt/WANdisco/lib -L/opt/WANdisco/lib -L/opt/csw//lib
-L/opt/WANdisco//lib -rpath /opt/WANdisco/lib -o svn add-cmd.lo
blame-cmd.lo cat-cmd.lo changelist-cmd.lo checkout-cmd.lo cl-conflicts.lo
cleanup-cmd.lo commit-cmd.lo conflict-callbacks.lo copy-cmd.lo
delete-cmd.lo deprecated.lo diff-cmd.lo export-cmd.lo file-merge.lo
help-cmd.lo import-cmd.lo info-cmd.lo list-cmd.lo lock-cmd.lo log-cmd.lo
merge-cmd.lo mergeinfo-cmd.lo mkdir-cmd.lo move-cmd.lo notify.lo
patch-cmd.lo propdel-cmd.lo propedit-cmd.lo propget-cmd.lo proplist-cmd.lo
props.lo propset-cmd.lo relocate-cmd.lo resolve-cmd.lo resolved-cmd.lo
revert-cmd.lo status-cmd.lo status.lo svn.lo switch-cmd.lo unlock-cmd.lo
update-cmd.lo upgrade-cmd.lo util.lo ../../subversion/libsvn_client/
libsvn_client-1.la ../../subversion/libsvn_wc/libsvn_wc-1.la
../../subversion/libsvn_ra/libsvn_ra-1.la ../../subversion/libsvn_delta/
libsvn_delta-1.la ../../subversion/libsvn_diff/libsvn_diff-1.la
../../subversion/libsvn_subr/libsvn_subr-1.la -L/opt/WANdisco/lib
-laprutil-1 -L/opt/WANdisco/lib -lapr-1 -lsocket
ld: warning: file ../../subversion/libsvn_wc/.libs/libsvn_wc-1.so: linked
to
/home/jenkins/SVN-Build/subversion-packaging/solaris/subversion-1.8.18/subversion/libsvn_wc/.libs/libsvn_wc-1.so:
attempted multiple inclusion of file
ld: warning: file ../../subversion/libsvn_ra/.libs/libsvn_ra-1.so: linked
to
/home/jenkins/SVN-Build/subversion-packaging/solaris/subversion-1.8.18/subversion/libsvn_ra/.libs/libsvn_ra-1.so:
attempted multiple inclusion of file
ld: warning: file ../../subversion/libsvn_delta/.libs/libsvn_delta-1.so:
linked to
/home/jenkins/SVN-Build/subversion-packaging/solaris/subversion-1.8.18/subversion/libsvn_delta/.libs/libsvn_delta-1.so:
attempted multiple inclusion of file
ld: warning: file ../../subversion/libsvn_diff/.libs/libsvn_diff-1.so:
linked to
/home/jenkins/SVN-Build/subversion-packaging/solaris/subversion-1.8.18/subversion/libsvn_diff/.libs/libsvn_diff-1.so:
attempted multiple inclusion of file
ld: warning: file ../../subversion/libsvn_subr/.libs/libsvn_subr-1.so:
linked to
/home/jenkins/SVN-Build/subversion-packaging/solaris/subversion-1.8.18/subversion/libsvn_subr/.libs/libsvn_subr-1.so:
attempted multiple inclusion of file
Undefined first referenced
 symbol in file
__sync_add_and_fetch
 /home/jenkins/SVN-Build/subversion-packaging/solaris/subversion-1.8.18/subversion/libsvn_subr/.libs/libsvn_subr-1.so
__sync_val_compare_and_swap
/home/jenkins/SVN-Build/subversion-packaging/solaris/subversion-1.8.18/subversion/libsvn_subr/.libs/libsvn_subr-1.so
__sync_lock_test_and_set
 /home/jenkins/SVN-Build/subversion-packaging/solaris/subversion-1.8.18/subversion/libsvn_subr/.libs/libsvn_subr-1.so
ld: fatal: symbol referencing errors. No output written to .libs/svn
*** Error code 2
make: Fatal error: Command failed for target `subversion/svn/svn'
+ fatal 'error compiling subversion'
+ echo '[FATAL]: error compiling subversion'
[FATAL]: error compiling subversion
+ exit -1

This is attempting to build with Oracle Developer Studio 12.6 and the
following dependencies built:
apr-1.6.2
apr-util-1.6.0
db-6.2.32
expat-2.2.2
httpd-2.2.34
neon-0.30.2
openssl-1.0.2l
pcre-8.41
sqlite-autoconf-3200000
zlib-1.2.11

Any idea what's wrong?

Thanks
Ian

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