Index: llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
===================================================================
--- llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -11515,6 +11515,9 @@
         // process to keep correct order.
         return Delayed;
       }
+      if (any_of(Entries,
+                 [&](const TreeEntry *E) { return PostponedGathers.count(E); }))
+        PostponedGathers.insert(E);
       assert((Entries.size() == 1 || Entries.size() == 2) &&
              "Expected shuffle of 1 or 2 entries.");
       if (!Resized) {