diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index ce3c5257e7114..423ed86ef41e2 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -10174,6 +10174,8 @@ bool RecordExprEvaluator::VisitCXXStdInitializerListExpr(
   if (!EvaluateLValue(E->getSubExpr(), Array, Info))
     return false;
 
+  assert(ArrayType && "unexpected type for array initializer");
+
   // Get a pointer to the first element of the array.
   Array.addArray(Info, E, ArrayType);