Merge pull request #38 from iris-cpp/fix-destructible

Fix `Cpp17Destructible` for pointer-to-class type

Author: saki7

include/iris/requirements.hpp

@@ -1,4 +1,4 @@
-#ifndef IRIS_REQUIREMENTS_HPP
+#ifndef IRIS_REQUIREMENTS_HPP
 #define IRIS_REQUIREMENTS_HPP
 
 // SPDX-License-Identifier: MIT
@@ -87,9 +87,8 @@ concept Cpp17CopyAssignable = Cpp17MoveAssignable<T> && requires {
 
 // https://eel.is/c++draft/utility.requirements#tab:cpp17.destructible
 template<class T>
-concept Cpp17Destructible = (!std::is_array_v<T>) && std::is_object_v<T> && requires(T u) {
-    { u.~T() };
-};
+concept Cpp17Destructible = std::is_object_v<T> && !std::is_array_v<T> && std::is_destructible_v<T>;
+// MSVC 2026 cannot compile `a.~T()` for pointer-to-class types (needs upstream bugfix)
 
 // https://eel.is/c++draft/swappable.requirements#5
 template<class X>

test/core.cpp

@@ -323,6 +323,11 @@ TEST_CASE("Cpp17CopyAssignable")
     }
 }
 
+template<class T>
+concept Cpp17Destructible_expr = requires(T a) {
+    a.~T();
+};
+
 TEST_CASE("Cpp17Destructible")
 {
     STATIC_REQUIRE(iris::req::Cpp17Destructible<int>);
@@ -369,6 +374,13 @@ TEST_CASE("Cpp17Destructible")
         STATIC_REQUIRE(!std::destructible<void>);
         STATIC_REQUIRE( std::destructible<int&>);
     }
+    {
+        // Pointer types *should* be destructible
+        STATIC_REQUIRE(iris::req::Cpp17Destructible<int*>);
+
+        struct Class;
+        STATIC_REQUIRE(iris::req::Cpp17Destructible<Class*>);
+    }
 }
 
 namespace {