be more explicit

[simgrid.git] / include / xbt / Extendable.hpp

diff --git a/include/xbt/Extendable.hpp b/include/xbt/Extendable.hpp
index f158d50..5cf36a9 100644 (file)
--- a/include/xbt/Extendable.hpp
+++ b/include/xbt/Extendable.hpp
@@ -24,7 +24,7 @@ class Extension {
   friend class Extendable<T>;
   constexpr Extension(std::size_t id) : id_(id) {}
 public:
-  constexpr Extension() : id_(INVALID_ID) {}
+  explicit constexpr Extension() : id_(INVALID_ID) {}
   std::size_t id() const { return id_; }
   bool valid() { return id_ != INVALID_ID; }
 };