Version 3.5.6.

src/ia32/full-codegen-ia32.cc

Index: src/ia32/full-codegen-ia32.cc
diff --git a/src/ia32/full-codegen-ia32.cc b/src/ia32/full-codegen-ia32.cc
index 0056acc953ea477dbab1cf6f09062afcf6873682..bb75b1e6acb22922dd13505981523e1be1e4521d 100644
--- a/src/ia32/full-codegen-ia32.cc
+++ b/src/ia32/full-codegen-ia32.cc
@@ -737,8 +737,10 @@ void FullCodeGenerator::EmitDeclaration(Variable* variable,
         __ push(esi);
         __ push(Immediate(variable->name()));
         // Declaration nodes are always introduced in one of two modes.
-        ASSERT(mode == Variable::VAR || mode == Variable::CONST);
-        PropertyAttributes attr = (mode == Variable::VAR) ? NONE : READ_ONLY;
+        ASSERT(mode == Variable::VAR ||
+               mode == Variable::CONST ||
+               mode == Variable::LET);
+        PropertyAttributes attr = (mode == Variable::CONST) ? READ_ONLY : NONE;
         __ push(Immediate(Smi::FromInt(attr)));
         // Push initial value, if any.
         // Note: For variables we must not push an initial value (such as