Index: lib/Target/WebAssembly/WebAssemblyLateEHPrepare.cpp
===================================================================
--- lib/Target/WebAssembly/WebAssemblyLateEHPrepare.cpp
+++ lib/Target/WebAssembly/WebAssemblyLateEHPrepare.cpp
@@ -91,12 +91,17 @@
   SmallVector<MachineBasicBlock *, 8> WL(MBBs.begin(), MBBs.end());
   while (!WL.empty()) {
     MachineBasicBlock *MBB = WL.pop_back_val();
+    SmallVector<MachineBasicBlock *, 4> Preds, Succs;
     for (auto *Pred : MBB->predecessors())
+      Preds.push_back(Pred);
+    for (auto *Pred : Preds)
       Pred->removeSuccessor(MBB);
     for (auto *Succ : MBB->successors()) {
+      Succs.push_back(Succ);
       WL.push_back(Succ);
-      MBB->removeSuccessor(Succ);
     }
+    for (auto *Succ : Succs)
+      MBB->removeSuccessor(Succ);
     MBB->eraseFromParent();
   }
 }