--- a/lib/AST/DeclBase.cpp	2019-12-11 22:15:30.000000000 +0300
+++ b/lib/AST/DeclBase.cpp	2020-02-21 22:15:30.000000000 +0300
@@ -146,7 +146,9 @@
   // are invalid too.
   if (auto *DD = dyn_cast<DecompositionDecl>(this)) {
     for (auto *Binding : DD->bindings()) {
-      Binding->setInvalidDecl();
+      if (Binding) {
+        Binding->setInvalidDecl();
+      }
     }
   }
 }