1 files changed, 3 insertions, 2 deletions
diff --git a/src/mbgl/style/expression/length.cpp b/src/mbgl/style/expression/length.cpp
index 258353ae4e..ad7a15675a 100644
--- a/src/mbgl/style/expression/length.cpp
+++ b/src/mbgl/style/expression/length.cpp
@@ -6,7 +6,7 @@ namespace style {
 namespace expression {
 
 Length::Length(std::unique_ptr<Expression> input_)
-    : Expression(type::Number),
+    : Expression(Kind::Length, type::Number),
       input(std::move(input_)) {
 }
 
@@ -30,7 +30,8 @@ void Length::eachChild(const std::function<void(const Expression&)>& visit) cons
 }
 
 bool Length::operator==(const Expression& e) const {
-    if (auto eq = dynamic_cast<const Length*>(&e)) {
+    if (e.getKind() == Kind::Length) {
+        auto eq = static_cast<const Length*>(&e);
         return *eq->input == *input;
     }
     return false;