diff --git a/src/ast/scopes.cc b/src/ast/scopes.cc
index eebaa5c3bf..bb3793b396 100644
--- a/src/ast/scopes.cc
+++ b/src/ast/scopes.cc
@@ -1187,7 +1187,7 @@ Declaration* DeclarationScope::CheckConflictingVarDeclarations() {
         // anything, so we can't conflict with anything either. The one
         // exception is the binding variable in catch scopes, which is handled
         // by the if above.
-        if (!IsLexicalVariableMode(other_var->mode())) return nullptr;
+        if (!IsLexicalVariableMode(other_var->mode())) break;
         return decl;
       }
       current = current->outer_scope();
diff --git a/test/mjsunit/regress/regress-1038588.js b/test/mjsunit/regress/regress-1038588.js
new file mode 100644
index 0000000000..ffa787a7dd
--- /dev/null
+++ b/test/mjsunit/regress/regress-1038588.js
@@ -0,0 +1,9 @@
+// Copyright 2020 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+function foo(arg){
+  const x = 0;
+  eval("var arg, x;");
+}
+assertThrows(foo, SyntaxError);