diff --git a/include/boost/fiber/fiber.hpp b/include/boost/fiber/fiber.hpp
index 4a1258a7..5ec5d903 100644
--- a/include/boost/fiber/fiber.hpp
+++ b/include/boost/fiber/fiber.hpp
@@ -326,7 +326,7 @@ public:
     { impl_.swap( other.impl_); }
 
     bool joinable() const BOOST_NOEXCEPT
-    { return impl_ && ! impl_->is_terminated(); }
+    { return impl_ /* && ! impl_->is_terminated() */; }
 
     id get_id() const BOOST_NOEXCEPT
     { return impl_ ? impl_->get_id() : id(); }