Index: tiffcomposite.cpp
===================================================================
--- tiffcomposite.cpp	(revision 2561)
+++ tiffcomposite.cpp	(revision 2562)
@@ -1689,11 +1689,19 @@
 
         if (elements_.empty()) return 0;
 
+        // Remaining assumptions:
+        // - array elements don't "overlap"
+        // - no duplicate tags in the array
         uint32_t idx = 0;
+        uint32_t sz = cfg()->tagStep();
         for (Components::const_iterator i = elements_.begin(); i != elements_.end(); ++i) {
-            idx = EXV_MAX(idx, (*i)->tag() * cfg()->tagStep());
-            idx += (*i)->size();
+            if ((*i)->tag() > idx) {
+                idx = (*i)->tag();
+                sz = (*i)->size();
+            }
         }
+        idx = idx * cfg()->tagStep() + sz;
+
         if (cfg()->hasFillers_ && def()) {
             const ArrayDef* lastDef = def() + defSize() - 1;
             uint16_t lastTag = static_cast<uint16_t>(lastDef->idx_ / cfg()->tagStep());