[goffice] Fix criticals related to data labels.

[Jean Bréfort <jbrefort src gnome org>]

commit 293476801f9801bee5ee32d6a92b934bd1608193
Author: Jean Brefort <jean brefort normalesup org>
Date:   Fri Dec 13 19:07:23 2019 +0100

    Fix criticals related to data labels.

 ChangeLog                         | 5 +++++
 NEWS                              | 1 +
 goffice/graph/gog-series-labels.c | 2 +-
 3 files changed, 7 insertions(+), 1 deletion(-)
---
diff --git a/ChangeLog b/ChangeLog
index f303c5ca..c80e4bb0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2019-12-13  Jean Brefort  <jean brefort normalesup org>
+
+       * goffice/graph/gog-series-labels.c (gog_series_labels_update):
+       a better fix.
+
 2019-12-13  Jean Brefort  <jean brefort normalesup org>
 
        * goffice/graph/gog-series-labels.c (gog_series_labels_update): fix warnings
diff --git a/NEWS b/NEWS
index f6d075c8..c99db6c9 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,7 @@ goffice 0.10.47:
 
 Jean:
        * Fix crash if a XY plot series has data labels but no valid data. [#426]
+       * Fix criticals related to data labels. [#428]
 
 Morten:
        * Fix library namespace issue.
diff --git a/goffice/graph/gog-series-labels.c b/goffice/graph/gog-series-labels.c
index d17a9ed9..fda796f5 100644
--- a/goffice/graph/gog-series-labels.c
+++ b/goffice/graph/gog-series-labels.c
@@ -1243,7 +1243,7 @@ gog_series_labels_update (GogObject *obj)
                                                        break;
                                                case 'c':
                                                        next = (GO_IS_DATA (labels->custom_labels[0].data) &&
-                                                               go_data_get_vector_size 
(labels->custom_labels[0].data) > 0)?
+                                                               go_data_get_vector_size 
(labels->custom_labels[0].data) > i)?
                                                                        go_data_get_vector_string 
(labels->custom_labels[0].data, i):
                                                                        NULL;
                                                        if (next) {