diff --git a/src/sdf/context.h b/src/sdf/context.h
index dbf5090d7..b67e4d438 100644
--- a/src/sdf/context.h
+++ b/src/sdf/context.h
@@ -28,8 +28,8 @@ struct Operand {
   bool isConst() const { return id <= -4; }
   bool isResult() const { return id > 0; }
   bool isNone() const { return id == 0; }
-  int toConstIndex() const { return -(id + 4); }
-  int toInstIndex() const { return id - 1; }
+  size_t toConstIndex() const { return static_cast<size_t>(-(id + 4)); }
+  size_t toInstIndex() const { return static_cast<size_t>(id - 1); }
   bool operator==(const Operand& other) const { return id == other.id; }
   bool operator!=(const Operand& other) const { return id != other.id; }
 };
diff --git a/src/sdf/tape.h b/src/sdf/tape.h
index 0f2aec70c..e80695b8a 100644
--- a/src/sdf/tape.h
+++ b/src/sdf/tape.h
@@ -115,11 +115,11 @@ struct EvalContext {
         Domain x = operand(tape[i + 2]);
         operand(tape[i + 1]) = handle_unary(current, x);
         i += 3;
-      // } else if (current == OpCode::CONST) {
-      //   double x;
-      //   std::memcpy(&x, tape.data() + i + 2, sizeof(x));
-      //   operand(tape[i + 1]) = x;
-      //   i += 2 + sizeof(x);
+        // } else if (current == OpCode::CONST) {
+        //   double x;
+        //   std::memcpy(&x, tape.data() + i + 2, sizeof(x));
+        //   operand(tape[i + 1]) = x;
+        //   i += 2 + sizeof(x);
       } else if (current == OpCode::RETURN) {
         return operand(tape[i + 1]);
       } else {