Notice: Undefined property: stdClass::$field_tags

Thanks for your report. Are you able to debug what field type causes this issue? I have not seen this myself yet, but I may missed this as I'm not using preview very often. field_tags is not something from linkchecker, too.

1539 foreach (field_info_instances($entity_type, $bundle_name) as $field_name => $instance) {
1540   $field = field_info_field($field_name);
1541   $entity_field = $entity->$field['field_name'];
1542
1543   switch ($field['type']) {

A repro plan on a new system would be great.

I do have the same problem. It happens will adding content. The error appears for empty reference fields. It only happens while adding the content, not while editing.

@evelien: Thanks for your report. Are you able to debug it to it's root cause, please? Please also note your core versions.

Same issue here, only when adding new content without tags. If I add new content with tag, issue doesn't appear.

Drupal 7.21
Link checker 7.x-1.1

This patch adds a workaround for this notice. For me it's not clear what core is doing here with the tags field. It may be a core bug as the tags field is completely missing in the entity if the form has been submitted with an empty tag list. This requires this bad catch logics.

I'm going to open a core issue to get an idea if this is a core fault or linkchecker need to expect this. If someone knows why - shed some light, please.

#1953804: field_tags is missing in $entity if field is empty on "node/add"

Just for the notes. These notice is functionality wise harmless. Nothing is or get's broken.

Changed to isset() per #1953804: field_tags is missing in $entity if field is empty on "node/add" and committed it to D7. Backport to D6 is not required.

See http://drupalcode.org/project/linkchecker.git/commit/0e7fc34

Same problem here with the current stable.

Would it perhaps make sense to release a new stable version? The patch works great for me!

Re-roll of the patch in #10 to apply against the current stable version of the module: 1.1.

#15 is working for me. Thanks.

Whoops. Didn't mean to reopen.

10# Works, thanks :)

15: linkchecker-notice-undefined-property-stdClass-field_tags-1923328-15.patch queued for re-testing.

Re-roll of the patch from #15 to apply against the current 7.x-1.x branch.