diff --git a/source/blender/makesrna/intern/rna_rna.c b/source/blender/makesrna/intern/rna_rna.c
index 507262675b3..6cd748c0026 100644
--- a/source/blender/makesrna/intern/rna_rna.c
+++ b/source/blender/makesrna/intern/rna_rna.c
@@ -335,7 +335,7 @@ static void rna_Struct_property_tags_begin(CollectionPropertyIterator *iter, Poi
 	/* here ptr->data should always be the same as iter->parent.type */
 	StructRNA *srna = (StructRNA *)ptr->data;
 	const EnumPropertyItem *tag_defines = RNA_struct_property_tag_defines(srna);
-	unsigned int tag_count = RNA_enum_items_count(tag_defines);
+	unsigned int tag_count = tag_defines ? RNA_enum_items_count(tag_defines) : 0;
 
 	rna_iterator_array_begin(iter, (void *)tag_defines, sizeof(EnumPropertyItem), tag_count, 0, NULL);
 }