* subversion/libsvn_client/conflicts.c
(resolve_incoming_move_dir_merge): Handle the case where yca_loc is NULL.
@@ -7847,6 +7847,22 @@ resolve_incoming_move_dir_merge(svn_client_conflict_option_t *option,
ctx, scratch_pool, scratch_pool);
if (err)
goto unlock_wc;
+
+ if (yca_loc == NULL)
+ {
+ err = svn_error_createf(SVN_ERR_WC_CONFLICT_RESOLVER_FAILURE, NULL,
+ _("Cannot resolve tree conflict on '%s' "
+ "(could not find common ancestor of '%s' "
+ " and '%s')"),
+ svn_dirent_local_style(local_abspath,
+ scratch_pool),
+ svn_dirent_local_style(victim_repos_relpath,
+ scratch_pool),
+ svn_dirent_local_style(moved_to_abspath,
+ scratch_pool));
+ goto unlock_wc;
+ }
+
yca_opt_rev.kind = svn_opt_revision_number;
yca_opt_rev.value.number = yca_loc->rev;
