disable incorrect coverity warnings

Co-authored-by: jll63 <5083077+jll63@users.noreply.github.com>

CMakeLists.txt

@@ -37,10 +37,35 @@ set(__ignore__ ${CMAKE_C_COMPILER})
 # Options
 #
 #-------------------------------------------------
-option(BOOST_OPENMETHOD_BUILD_TESTS "Build boost::openmethod tests even if BUILD_TESTING is OFF" OFF)
-option(BOOST_OPENMETHOD_BUILD_EXAMPLES "Build boost::openmethod examples" ${BOOST_OPENMETHOD_IS_ROOT})
-option(BOOST_OPENMETHOD_MRDOCS_BUILD "Build the target for MrDocs: see mrdocs.yml" OFF)
-option(BOOST_OPENMETHOD_WARNINGS_AS_ERRORS "Treat warnings as errors" OFF)
+
+option(
+    BOOST_OPENMETHOD_BUILD_TESTS
+    "Build boost::openmethod tests even if BUILD_TESTING is OFF"
+    ${BOOST_OPENMETHOD_IS_ROOT})
+
+if (BUILD_TESTING)
+    set(BOOST_OPENMETHOD_BUILD_TESTS ON)
+endif ()
+
+option(
+    BOOST_OPENMETHOD_BUILD_EXAMPLES
+    "Build boost::openmethod examples"
+    ${BOOST_OPENMETHOD_IS_ROOT})
+option(
+    BOOST_OPENMETHOD_MRDOCS_BUILD
+    "Build the target for MrDocs: see mrdocs.yml"
+    OFF)
+option(
+    BOOST_OPENMETHOD_WARNINGS_AS_ERRORS
+    "Treat warnings as errors"
+    OFF)
+
+if (BOOST_OPENMETHOD_BUILD_EXAMPLES AND NOT BOOST_OPENMETHOD_BUILD_TESTS)
+    message(
+        WARNING
+        "BOOST_OPENMETHOD_BUILD_EXAMPLES requires BOOST_OPENMETHOD_BUILD_TESTS. Examples will not be built.")
+    set(BOOST_OPENMETHOD_BUILD_EXAMPLES OFF)
+endif()
 
 # Check if environment variable BOOST_SRC_DIR is set
 if (NOT DEFINED BOOST_SRC_DIR AND DEFINED ENV{BOOST_SRC_DIR})
@@ -67,21 +92,30 @@ set(
     Boost::preprocessor
 )
 
+if (BOOST_OPENMETHOD_BUILD_TESTS OR BOOST_OPENMETHOD_MRDOCS_BUILD)
+    list(APPEND BOOST_OPENMETHOD_DEPENDENCIES Boost::smart_ptr)
+endif()
 
 foreach (BOOST_OPENMETHOD_DEPENDENCY ${BOOST_OPENMETHOD_DEPENDENCIES})
     if (BOOST_OPENMETHOD_DEPENDENCY MATCHES "^[ ]*Boost::([A-Za-z0-9_]+)[ ]*$")
         list(APPEND BOOST_OPENMETHOD_INCLUDE_LIBRARIES ${CMAKE_MATCH_1})
     endif ()
 endforeach ()
+
 # Conditional dependencies
+if (BOOST_OPENMETHOD_MRDOCS_BUILD)
+    list(APPEND BOOST_OPENMETHOD_INCLUDE_LIBRARIES smart_ptr)
+endif()
+
 if (NOT BOOST_OPENMETHOD_MRDOCS_BUILD)
-    if (BUILD_TESTING OR BOOST_OPENMETHOD_BUILD_TESTS)
+    if (BOOST_OPENMETHOD_BUILD_TESTS)
         set(BOOST_OPENMETHOD_UNIT_TEST_LIBRARIES test)
-    endif()
-    if (BOOST_OPENMETHOD_BUILD_EXAMPLES)
-        set(BOOST_OPENMETHOD_EXAMPLE_LIBRARIES dll)
+        if (BOOST_OPENMETHOD_BUILD_EXAMPLES)
+            set(BOOST_OPENMETHOD_EXAMPLE_LIBRARIES dll)
+        endif()
     endif()
 endif()
+
 # Complete dependency list
 set(BOOST_INCLUDE_LIBRARIES ${BOOST_OPENMETHOD_INCLUDE_LIBRARIES} ${BOOST_OPENMETHOD_UNIT_TEST_LIBRARIES} ${BOOST_OPENMETHOD_EXAMPLE_LIBRARIES})
 set(BOOST_EXCLUDE_LIBRARIES openmethod)
@@ -175,20 +209,15 @@ endif()
 # Tests
 #
 #-------------------------------------------------
-if (BUILD_TESTING OR BOOST_OPENMETHOD_BUILD_TESTS)
+if (BOOST_OPENMETHOD_BUILD_TESTS)
     enable_testing()
     add_subdirectory(test)
     if (BOOST_OPENMETHOD_IS_ROOT)
         add_custom_target(all_with_tests ALL DEPENDS tests)
     endif()
-endif ()
 
-#-------------------------------------------------
-#
-# Examples
-#
-#-------------------------------------------------
-if (BOOST_OPENMETHOD_BUILD_EXAMPLES)
-    enable_testing()
-    add_subdirectory(doc/modules/ROOT/examples)
+    # Examples
+    if (BOOST_OPENMETHOD_BUILD_EXAMPLES)
+        add_subdirectory(doc/modules/ROOT/examples)
+    endif ()
 endif ()

doc/modules/ROOT/examples/matrix.cpp

@@ -3,146 +3,153 @@
 // See accompanying file LICENSE_1_0.txt
 // or copy at http://www.boost.org/LICENSE_1_0.txt)
 
+// https://godbolt.org/z/r6o4f171r
+
 #include <iostream>
 #include <memory>
 #include <string>
 #include <typeinfo>
 
 #include <boost/openmethod.hpp>
+#include <boost/openmethod/policies/static_rtti.hpp>
 #include <boost/openmethod/initialize.hpp>
-#include <boost/openmethod/interop/std_shared_ptr.hpp>
 
-using std::make_shared;
-using std::shared_ptr;
 using std::string;
 
-using boost::openmethod::make_shared_virtual;
-using boost::openmethod::shared_virtual_ptr;
-using boost::openmethod::virtual_ptr;
+using namespace boost::openmethod::aliases;
 
-struct matrix {
-    virtual ~matrix() {
-    }
-    virtual auto at(int row, int col) const -> double = 0;
-    // ...
+struct abstract {
+    int ref_count = 0;
 };
 
-struct dense_matrix : matrix {
-    virtual auto at(int /*row*/, int /*col*/) const -> double {
-        return 0;
+struct registry
+    : boost::openmethod::registry<boost::openmethod::policies::static_rtti> {};
+
+template<class Rep>
+using matrix_ptr = boost::openmethod::virtual_ptr<Rep, registry>;
+
+BOOST_OPENMETHOD(destroy, (matrix_ptr<abstract>), void, registry);
+
+class matrix {
+    matrix_ptr<abstract> rep_;
+
+    explicit matrix(matrix_ptr<abstract> rep) : rep_(rep) {
+        ++rep_->ref_count;
+
+        if (--rep->ref_count == 0) {
+            destroy(rep);
+        }
+    }
+
+  public:
+    matrix(const matrix&) = default;
+    matrix& operator=(const matrix&) = default;
+
+    auto rep() const -> matrix_ptr<abstract> {
+        return rep_;
+    }
+
+    template<class Rep, class... Args>
+    static matrix make(Args&&... args) {
+        return matrix(
+            boost::openmethod::final_virtual_ptr<registry>(
+                *new Rep(std::forward<Args>(args)...)));
     }
 };
 
-struct diagonal_matrix : matrix {
-    virtual auto at(int /*row*/, int /*col*/) const -> double {
-        return 0;
-    }
+struct dense : abstract {
+    static constexpr const char* type = "dense";
 };
 
-BOOST_OPENMETHOD_CLASSES(matrix, dense_matrix, diagonal_matrix);
-
-BOOST_OPENMETHOD(to_json, (virtual_ptr<const matrix>), string);
-
-BOOST_OPENMETHOD_OVERRIDE(to_json, (virtual_ptr<const dense_matrix>), string) {
-    return "json for dense matrix...";
+BOOST_OPENMETHOD_OVERRIDE(destroy, (matrix_ptr<dense> rep), void) {
+    delete rep.get();
 }
 
-BOOST_OPENMETHOD_OVERRIDE(
-    to_json, (virtual_ptr<const diagonal_matrix>), string) {
-    return "json for diagonal matrix...";
+struct diagonal : abstract {
+    static constexpr const char* type = "diagonal";
+};
+
+BOOST_OPENMETHOD_OVERRIDE(destroy, (matrix_ptr<diagonal> rep), void) {
+    delete rep.get();
 }
 
+BOOST_OPENMETHOD_CLASSES(abstract, dense, diagonal, registry);
+
 // -----------------------------------------------------------------------------
 // matrix * matrix
 
 BOOST_OPENMETHOD(
-    times, (shared_virtual_ptr<const matrix>, shared_virtual_ptr<const matrix>),
-    shared_virtual_ptr<const matrix>);
+    times, (matrix_ptr<abstract>, matrix_ptr<abstract>), matrix, registry);
 
-// catch-all matrix * matrix -> dense_matrix
+// catch-all matrix * matrix -> dense
 BOOST_OPENMETHOD_OVERRIDE(
-    times,
-    (shared_virtual_ptr<const matrix> /*a*/,
-     shared_virtual_ptr<const matrix> /*b*/),
-    shared_virtual_ptr<const dense_matrix>) {
-    return make_shared<const dense_matrix>();
+    times, (matrix_ptr<abstract> /*a*/, matrix_ptr<abstract> /*b*/), matrix) {
+    return matrix::make<dense>();
 }
 
-// diagonal_matrix * diagonal_matrix -> diagonal_matrix
+// diagonal * diagonal -> diagonal
 BOOST_OPENMETHOD_OVERRIDE(
-    times,
-    (shared_virtual_ptr<const diagonal_matrix> /*a*/,
-     shared_virtual_ptr<const diagonal_matrix> /*b*/),
-    shared_virtual_ptr<const diagonal_matrix>) {
-    return make_shared_virtual<diagonal_matrix>();
+    times, (matrix_ptr<diagonal> /*a*/, matrix_ptr<diagonal> /*b*/), matrix) {
+    return matrix::make<diagonal>();
 }
 
-inline auto operator*(shared_ptr<const matrix> a, shared_ptr<const matrix> b)
-    -> shared_virtual_ptr<const matrix> {
-    return times(a, b);
+inline auto operator*(matrix a, matrix b) -> matrix {
+    return times(a.rep(), b.rep());
 }
 
 // -----------------------------------------------------------------------------
 // scalar * matrix
 
-BOOST_OPENMETHOD(
-    times, (double, shared_virtual_ptr<const matrix>),
-    shared_virtual_ptr<const matrix>);
+BOOST_OPENMETHOD(times, (double, matrix_ptr<abstract>), matrix, registry);
 
-// catch-all matrix * scalar -> dense_matrix
+// catch-all matrix * scalar -> dense
 BOOST_OPENMETHOD_OVERRIDE(
-    times, (double /*a*/, shared_virtual_ptr<const matrix> /*b*/),
-    shared_virtual_ptr<const dense_matrix>) {
-    return make_shared_virtual<dense_matrix>();
+    times, (double /*a*/, matrix_ptr<abstract> /*b*/), matrix) {
+    return matrix::make<dense>();
 }
 
 BOOST_OPENMETHOD_OVERRIDE(
-    times, (double /*a*/, shared_virtual_ptr<const diagonal_matrix> /*b*/),
-    shared_virtual_ptr<const diagonal_matrix>) {
-    return make_shared_virtual<diagonal_matrix>();
+    times, (double /*a*/, matrix_ptr<diagonal> /*b*/), matrix) {
+    return matrix::make<diagonal>();
 }
 
 // -----------------------------------------------------------------------------
 // matrix * scalar
 
 // just swap
-inline auto times(shared_virtual_ptr<const matrix> a, double b)
-    -> shared_virtual_ptr<const matrix> {
+inline auto times(matrix_ptr<abstract> a, double b) -> matrix {
     return times(b, a);
 }
 
 // -----------------------------------------------------------------------------
 // main
 
-#define check(expr)                                                            \
-    {                                                                          \
-        if (!(expr)) {                                                         \
-            cerr << #expr << " failed\n";                                      \
-        }                                                                      \
-    }
+BOOST_OPENMETHOD(write, (matrix_ptr<abstract>), string, registry);
+
+inline auto operator<<(std::ostream& os, matrix a) -> std::ostream& {
+    return os << write(a.rep());
+}
+
+BOOST_OPENMETHOD_OVERRIDE(write, (matrix_ptr<dense>), string) {
+    return "a dense matrix";
+}
+
+BOOST_OPENMETHOD_OVERRIDE(write, (matrix_ptr<diagonal>), string) {
+    return "a diagonal matrix";
+}
 
 auto main() -> int {
     using std::cerr;
     using std::cout;
 
-    boost::openmethod::initialize();
+    boost::openmethod::initialize<registry>();
 
-    shared_ptr<const matrix> a = make_shared<dense_matrix>();
-    shared_ptr<const matrix> b = make_shared<diagonal_matrix>();
+    matrix a = matrix::make<dense>();
+    matrix b = matrix::make<diagonal>();
     double s = 1;
 
-#ifdef BOOST_CLANG
-#pragma clang diagnostic ignored "-Wpotentially-evaluated-expression"
-#endif
-
-    check(typeid(*times(a, a)) == typeid(dense_matrix));
-    check(typeid(*times(a, b)) == typeid(dense_matrix));
-    check(typeid(*times(b, b)) == typeid(diagonal_matrix));
-    check(typeid(*times(s, a)) == typeid(dense_matrix));
-    check(typeid(*times(s, b)) == typeid(diagonal_matrix));
-
-    cout << to_json(*a) << "\n"; // json for dense matrix
-    cout << to_json(*b) << "\n"; // json for diagonal matrix
+    cout << a << "\n";
+    cout << b << "\n";
 
     return 0;
 }

doc/modules/ROOT/examples/matrix_intrusive_vptr.cpp

@@ -0,0 +1,150 @@
+// Copyright (c) 2018-2025 Jean-Louis Leroy
+// Distributed under the Boost Software License, Version 1.0.
+// See accompanying file LICENSE_1_0.txt
+// or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+#include <iostream>
+#include <memory>
+#include <string>
+#include <typeinfo>
+
+#include <boost/openmethod.hpp>
+#include <boost/openmethod/initialize.hpp>
+#include <boost/openmethod/interop/boost_intrusive_ptr.hpp>
+
+using std::string;
+
+using namespace boost::openmethod::aliases;
+
+struct abstract {
+    virtual ~abstract() {
+    }
+
+    int ref_count = 0;
+
+    friend void intrusive_ptr_add_ref(abstract* p) {
+        ++p->ref_count;
+    }
+
+    friend void intrusive_ptr_release(abstract* p) {
+        if (--p->ref_count == 0) {
+            delete p;
+        }
+    }
+};
+
+template<class Rep>
+using matrix_ptr = boost::openmethod::boost_intrusive_virtual_ptr<Rep>;
+
+class matrix {
+    matrix_ptr<abstract> rep_;
+
+    explicit matrix(matrix_ptr<abstract> rep) : rep_(rep) {
+    }
+
+  public:
+    matrix(const matrix&) = default;
+    matrix& operator=(const matrix&) = default;
+
+    auto rep() const -> matrix_ptr<abstract> {
+        return rep_;
+    }
+
+    template<class Rep>
+    static matrix make() {
+        return matrix(boost::openmethod::make_boost_intrusive_virtual<Rep>());
+    }
+};
+
+struct dense : abstract {};
+
+struct diagonal : abstract {};
+
+using namespace boost::openmethod::aliases;
+
+BOOST_OPENMETHOD_CLASSES(abstract, dense, diagonal);
+
+BOOST_OPENMETHOD(to_str, (matrix_ptr<abstract>), string);
+
+inline auto operator<<(std::ostream& os, matrix a) -> std::ostream& {
+    return os << to_str(a.rep());
+}
+
+BOOST_OPENMETHOD_OVERRIDE(to_str, (matrix_ptr<dense>), string) {
+    return "a dense matrix";
+}
+
+BOOST_OPENMETHOD_OVERRIDE(to_str, (matrix_ptr<diagonal>), string) {
+    return "a diagonal matrix";
+}
+
+// -----------------------------------------------------------------------------
+// matrix * matrix
+
+BOOST_OPENMETHOD(times, (matrix_ptr<abstract>, matrix_ptr<abstract>), matrix);
+
+// catch-all matrix * matrix -> dense
+BOOST_OPENMETHOD_OVERRIDE(
+    times, (matrix_ptr<abstract> /*a*/, matrix_ptr<abstract> /*b*/), matrix) {
+    return matrix::make<dense>();
+}
+
+// diagonal * diagonal -> diagonal
+BOOST_OPENMETHOD_OVERRIDE(
+    times, (matrix_ptr<diagonal> /*a*/, matrix_ptr<diagonal> /*b*/), matrix) {
+    return matrix::make<diagonal>();
+}
+
+inline auto operator*(matrix a, matrix b) -> matrix {
+    return times(a.rep(), b.rep());
+}
+
+// -----------------------------------------------------------------------------
+// scalar * matrix
+
+BOOST_OPENMETHOD(times, (double, matrix_ptr<abstract>), matrix);
+
+// catch-all matrix * scalar -> dense
+BOOST_OPENMETHOD_OVERRIDE(
+    times, (double /*a*/, matrix_ptr<abstract> /*b*/), matrix) {
+    return matrix::make<dense>();
+}
+
+BOOST_OPENMETHOD_OVERRIDE(
+    times, (double /*a*/, matrix_ptr<diagonal> /*b*/), matrix) {
+    return matrix::make<diagonal>();
+}
+
+// -----------------------------------------------------------------------------
+// matrix * scalar
+
+// just swap
+inline auto times(matrix_ptr<abstract> a, double b) -> matrix {
+    return times(b, a);
+}
+
+// -----------------------------------------------------------------------------
+// main
+
+#define check(expr)                                                            \
+    {                                                                          \
+        if (!(expr)) {                                                         \
+            cerr << #expr << " failed\n";                                      \
+        }                                                                      \
+    }
+
+auto main() -> int {
+    using std::cerr;
+    using std::cout;
+
+    boost::openmethod::initialize();
+
+    matrix a = matrix::make<dense>();
+    matrix b = matrix::make<diagonal>();
+    double s = 1;
+
+    cout << a << "\n";
+    cout << b << "\n";
+
+    return 0;
+}

doc/modules/ROOT/examples/rolex/1/employee.cpp

@@ -14,5 +14,5 @@ BOOST_OPENMETHOD_OVERRIDE(
     return 5000.0;
 }
 
-BOOST_OPENMETHOD_CLASSES(Employee)
+BOOST_OPENMETHOD_CLASSES(Employee);
 // end::content[]

doc/modules/ROOT/examples/rolex/1/salesman.cpp

@@ -14,6 +14,6 @@ BOOST_OPENMETHOD_OVERRIDE(
     return next(emp) + emp->sales * 0.05; // base + commission
 }
 
-BOOST_OPENMETHOD_CLASSES(Employee, Salesman)
+BOOST_OPENMETHOD_CLASSES(Employee, Salesman);
 
 // end::content[]

doc/modules/ROOT/examples/rolex/2/employee.cpp

@@ -12,5 +12,5 @@ BOOST_OPENMETHOD_DEFINE_OVERRIDER(
     return 5000.0;
 }
 
-BOOST_OPENMETHOD_CLASSES(Employee)
+BOOST_OPENMETHOD_CLASSES(Employee);
 // end::content[]

doc/modules/ROOT/examples/rolex/2/salesman.cpp

@@ -16,4 +16,4 @@ BOOST_OPENMETHOD_OVERRIDE(
 }
 // end::content[]
 
-BOOST_OPENMETHOD_CLASSES(Employee, Salesman)
+BOOST_OPENMETHOD_CLASSES(Employee, Salesman);

doc/modules/ROOT/examples/rolex/3/employee.cpp

@@ -7,5 +7,5 @@
 #include "roles.hpp"
 #include <boost/openmethod.hpp>
 
-BOOST_OPENMETHOD_CLASSES(Employee)
+BOOST_OPENMETHOD_CLASSES(Employee);
 // end::content[]

doc/modules/ROOT/examples/rolex/3/salesman.cpp

@@ -16,4 +16,4 @@ BOOST_OPENMETHOD_OVERRIDE(
 }
 // end::content[]
 
-BOOST_OPENMETHOD_CLASSES(Employee, Salesman)
+BOOST_OPENMETHOD_CLASSES(Employee, Salesman);

doc/modules/ROOT/examples/rolex/4/employee.cpp

@@ -7,5 +7,5 @@
 #include "roles.hpp"
 #include <boost/openmethod.hpp>
 
-BOOST_OPENMETHOD_CLASSES(employees::Employee)
+BOOST_OPENMETHOD_CLASSES(employees::Employee);
 // end::content[]

doc/modules/ROOT/examples/rolex/4/salesman.cpp

@@ -17,7 +17,7 @@ BOOST_OPENMETHOD_OVERRIDE(
         emp->sales * 0.05; // base + commission
 }
 
-BOOST_OPENMETHOD_CLASSES(employees::Employee, Salesman)
+BOOST_OPENMETHOD_CLASSES(employees::Employee, Salesman);
 
 } // namespace sales
 // end::content[]

doc/modules/ROOT/examples/rolex/5/main.cpp

@@ -71,7 +71,7 @@ BOOST_OPENMETHOD_OVERRIDE(
 }
 
 // ...and let's not forget to register the classes
-BOOST_OPENMETHOD_CLASSES(Employee, Salesman)
+BOOST_OPENMETHOD_CLASSES(Employee, Salesman);
 // end::overriders[]
 
 // tag::main[]

doc/modules/ROOT/examples/rolex/6/main.cpp

@@ -66,7 +66,7 @@ BOOST_OPENMETHOD_OVERRIDE(
 }
 
 // ...and let's not forget to register the classes
-BOOST_OPENMETHOD_CLASSES(Employee, Salesman)
+BOOST_OPENMETHOD_CLASSES(Employee, Salesman);
 // end::overriders[]
 
 // tag::main[]

doc/modules/ROOT/examples/shared_libs/CMakeLists.txt

@@ -12,7 +12,10 @@ add_compile_definitions(BOOST_OPENMETHOD_ENABLE_RUNTIME_CHECKS)
 
 add_library(boost_openmethod-shared SHARED extensions.cpp)
 target_link_libraries(boost_openmethod-shared Boost::openmethod)
-set_target_properties(boost_openmethod-shared PROPERTIES ENABLE_EXPORTS ON)
+set_target_properties(boost_openmethod-shared PROPERTIES
+    ENABLE_EXPORTS ON
+    OUTPUT_NAME shared
+)
 
 add_executable(boost_openmethod-static static_main.cpp)
 target_link_libraries(boost_openmethod-static Boost::openmethod Boost::dll boost_openmethod-shared)
@@ -36,7 +39,10 @@ add_library(boost_openmethod-indirect_shared SHARED indirect_extensions.cpp)
 target_compile_definitions(
     boost_openmethod-indirect_shared PUBLIC BOOST_OPENMETHOD_DEFAULT_REGISTRY=indirect_registry)
 target_link_libraries(boost_openmethod-indirect_shared PRIVATE Boost::openmethod Boost::dll)
-set_target_properties(boost_openmethod-indirect_shared PROPERTIES ENABLE_EXPORTS ON)
+set_target_properties(boost_openmethod-indirect_shared PROPERTIES
+    ENABLE_EXPORTS ON
+    OUTPUT_NAME indirect_shared
+)
 
 add_executable(boost_openmethod-indirect indirect_main.cpp)
 target_compile_definitions(

doc/modules/ROOT/pages/basics.adoc

@@ -6,7 +6,7 @@ An _open-method_ is a free-standing function that has one or more _virtual_
 _parameters_. When it is called, it forwards to an _overrider_ selected from a
 set by examining the dynamic types of the virtual parameters.
 
-If this sounds like a virtual function, that's because because an open-method
+If this sounds like a virtual function, that's because an open-method
 with one virtual parameter is equivalent to a virtual function - with one big
 difference: it exists outside of classes.
 

doc/modules/ROOT/pages/ref_headers.adoc

@@ -65,6 +65,12 @@ Provides a `virtual_traits` specialization that makes it possible to use a
 Provides a `virtual_traits` specialization that makes it possible to use a
 `std::unique_ptr` in place of a raw pointer or reference in virtual parameters.
 
+[#boost_intrusive_ptr]
+### link:{{BASE_URL}}/include/boost/openmethod/interop/boost_intrusive_ptr.hpp[<boost/openmethod/interop/boost_intrusive_ptr.hpp>]
+
+Provides a `virtual_traits` specialization that makes it possible to use a
+`boost::intrusive_ptr` in place of a raw pointer or reference in virtual parameters.
+
 *The headers below are for advanced use*.
 
 ## Pre-Core Headers

include/boost/openmethod/core.hpp

@@ -2844,14 +2844,21 @@ struct VirtualTraits {
 
     //! Casts a virtual argument.
     //!
-    //! Casts a virtual argument to the type expected by the overrider.
+    //! `cast` is responsible for passing virtual arguments from method to
+    //! overrider. In general, this requires some form of adjustment, because a
+    //! virtual parameter in the overrider usually has a different type than the
+    //! corresponding parameter in the method. Typically, the adjustment
+    //! consists of a cast, performed via `static_cast`, `dynamic_cast`, or
+    //! other means, depending on the type of the argument and the rtti policy
+    //! of the method. `cast` may return the adjusted argument by reference or
+    //! as a temporary value.
     //!
-    //! @tparam T The type of a virtual parameter of a method.
-    //! @tparam U The type of a virtual parameter of an overrider.
-    //! @param arg The argument passed to a method call.
-    //! @return A reference to the argument, cast to `U`.
+    //! @tparam T The type of the virtual parameter in the method.
+    //! @tparam U The type of the virtual parameter in the overrider.
+    //! @param arg The argument passed to the method call.
+    //! @return A value that can be passed as a U.
     template<typename U>
-    static auto cast(T arg) -> U;
+    static auto cast(T arg) -> detail::unspecified;
 
     //! Rebind to a another class (smart pointers only).
     //!

include/boost/openmethod/detail/ostdstream.hpp

@@ -10,6 +10,7 @@
 #include <cstdio>
 #include <charconv>
 #include <random>
+#include <string_view>
 
 namespace boost::openmethod {
 

include/boost/openmethod/detail/static_list.hpp

@@ -127,10 +127,11 @@ class static_list {
 
         friend auto operator==(const iterator& a, const iterator& b) -> bool {
             return a.ptr == b.ptr;
-        };
+        }
+
         friend auto operator!=(const iterator& a, const iterator& b) -> bool {
             return a.ptr != b.ptr;
-        };
+        }
 
       private:
         T* ptr;
@@ -179,11 +180,12 @@ class static_list {
         friend auto
         operator==(const const_iterator& a, const const_iterator& b) -> bool {
             return a.ptr == b.ptr;
-        };
+        }
+
         friend auto
         operator!=(const const_iterator& a, const const_iterator& b) -> bool {
             return a.ptr != b.ptr;
-        };
+        }
 
       private:
         T* ptr;

include/boost/openmethod/interop/boost_intrusive_ptr.hpp

@@ -0,0 +1,150 @@
+// Copyright (c) 2018-2025 Jean-Louis Leroy
+// Distributed under the Boost Software License, Version 1.0.
+// See accompanying file LICENSE_1_0.txt
+// or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+#ifndef BOOST_OPENMETHOD_INTEROP_BOOST_INTRUSIVE_PTR_HPP
+#define BOOST_OPENMETHOD_INTEROP_BOOST_INTRUSIVE_PTR_HPP
+
+#include <boost/openmethod/core.hpp>
+#include <boost/smart_ptr/intrusive_ptr.hpp>
+#include <memory>
+
+namespace boost::openmethod {
+
+//! Specialize virtual_traits for boost::intrusive_ptr.
+//!
+//! @tparam Class A class type, possibly cv-qualified.
+//! @tparam Registry A @ref registry.
+template<typename Class, class Registry>
+struct virtual_traits<boost::intrusive_ptr<Class>, Registry> {
+    //! Rebind to a different element type.
+    //!
+    //! @tparam Other The new element type.
+    template<class Other>
+    using rebind = boost::intrusive_ptr<Other>;
+
+    //! `Class`, stripped from cv-qualifiers.
+    using virtual_type = std::remove_cv_t<Class>;
+
+    //! Return a reference to a non-modifiable `Class` object.
+    //! @param arg A reference to a `boost::intrusive_ptr<Class>`.
+    //! @return A reference to the object pointed to.
+    static auto peek(const boost::intrusive_ptr<Class>& arg) -> const Class& {
+        return *arg;
+    }
+
+    //! Cast method argument to overrider argument.
+    //!
+    //! Cast a `boost::intrusive_ptr` to a `boost::intrusive_ptr` to a derived
+    //! class, using a static cast if possible, and a dynamic cast otherwise.
+    //!
+    //! @tparam OverriderType The type required by the overrider (a
+    //! `boost::intrusive_ptr`).
+    //! @param obj The method's argument..
+    //! @return A `boost::intrusive_ptr` _value_.
+    template<class OverriderType>
+    static auto cast(const boost::intrusive_ptr<Class>& obj) {
+        using element_type = typename OverriderType::element_type;
+
+        if constexpr (detail::requires_dynamic_cast<Class*, element_type*>) {
+            // make it work with custom RTTI
+            return OverriderType(
+                &Registry::rtti::template dynamic_cast_ref<element_type&>(
+                    *obj));
+        } else {
+            return boost::static_pointer_cast<element_type>(obj);
+        }
+    }
+};
+
+//! Specialize virtual_traits for const boost::intrusive_ptr&.
+//!
+//! @tparam Class A class type, possibly cv-qualified.
+//! @tparam Registry A @ref registry.
+template<class Class, class Registry>
+struct virtual_traits<const boost::intrusive_ptr<Class>&, Registry> {
+  public:
+    //! Rebind to a different element type.
+    //!
+    //! @tparam Other The new element type.
+    template<class Other>
+    using rebind = boost::intrusive_ptr<Other>;
+
+    //! `Class`, stripped from cv-qualifiers.
+    using virtual_type = std::remove_cv_t<Class>;
+
+    //! Return a reference to a non-modifiable `Class` object.
+    //! @param arg A reference to a `boost::intrusive_ptr<Class>`.
+    //! @return A reference to the object pointed to.
+    static auto peek(const boost::intrusive_ptr<Class>& arg) -> const Class& {
+        return *arg;
+    }
+
+    //! Cast method argument to overrider argument.
+    //!
+    //! Cast a `boost::intrusive_ptr` to a `boost::intrusive_ptr` to a derived
+    //! class, using a static cast if possible, and a dynamic cast otherwise.
+    //!
+    //! @tparam OverriderType The type required by the overrider (a `const
+    //! boost::intrusive_ptr&`).
+    //! @param obj The method's argument..
+    //! @return A `boost::intrusive_ptr` _value_.
+    template<class OverriderType>
+    static decltype(auto) cast(const boost::intrusive_ptr<Class>& obj) {
+        if constexpr (std::is_same_v<
+                          OverriderType, const boost::intrusive_ptr<Class>&>) {
+            return obj;
+        } else {
+            using element_type =
+                typename std::remove_reference_t<OverriderType>::element_type;
+
+            if constexpr (detail::requires_dynamic_cast<
+                              Class*, element_type*>) {
+                // make it work with custom RTTI
+                return std::remove_const_t<
+                    std::remove_reference_t<OverriderType>>(
+                    &Registry::rtti::template dynamic_cast_ref<element_type&>(
+                        *obj));
+            } else {
+                return boost::static_pointer_cast<element_type>(obj);
+            }
+        }
+    }
+};
+
+//! Alias for a `virtual_ptr<boost::intrusive_ptr<T>>`.
+template<class Class, class Registry = BOOST_OPENMETHOD_DEFAULT_REGISTRY>
+using boost_intrusive_virtual_ptr =
+    virtual_ptr<boost::intrusive_ptr<Class>, Registry>;
+
+//! Create a new object and return a `boost_intrusive_virtual_ptr` to it.
+//!
+//! Create an object using `std::make_shared`, and return a @ref
+//! boost_intrusive_virtual_ptr pointing to it. Since the exact class of the
+//! object is known, the `virtual_ptr` is created using @ref final_virtual_ptr.
+//!
+//! `Class` is _not_ required to be a polymorphic class.
+//!
+//! @tparam Class The class of the object to create.
+//! @tparam Registry A @ref registry.
+//! @tparam T Types of the arguments to pass to the constructor of `Class`.
+//! @param args Arguments to pass to the constructor of `Class`.
+//! @return A `boost_intrusive_virtual_ptr<Class, Registry>` pointing to a newly
+//! created object of type `Class`.
+template<
+    class Class, class Registry = BOOST_OPENMETHOD_DEFAULT_REGISTRY,
+    typename... T>
+inline auto make_boost_intrusive_virtual(T&&... args) {
+    return final_virtual_ptr<Registry>(intrusive_ptr<Class>(
+        new std::remove_cv_t<Class>(std::forward<T>(args)...)));
+}
+
+namespace aliases {
+using boost::openmethod::boost_intrusive_virtual_ptr;
+using boost::openmethod::make_boost_intrusive_virtual;
+} // namespace aliases
+
+} // namespace boost::openmethod
+
+#endif

include/boost/openmethod/interop/std_shared_ptr.hpp

@@ -167,15 +167,20 @@ struct virtual_traits<const std::shared_ptr<Class>&, Registry> {
     //! @return A `std::shared_ptr` to the same object, cast to
     //! `Derived::element_type`.
     template<class Other>
-    static auto cast(const std::shared_ptr<Class>& obj) {
-        using namespace boost::openmethod::detail;
-
-        if constexpr (requires_dynamic_cast<Class*, Other>) {
-            return std::dynamic_pointer_cast<
-                typename shared_ptr_cast_traits<Other>::virtual_type>(obj);
+    static decltype(auto) cast(const std::shared_ptr<Class>& obj) {
+        if constexpr (std::is_same_v<Other, const std::shared_ptr<Class>&>) {
+            // avoid unnecessary copy
+            return obj;
         } else {
-            return std::static_pointer_cast<
-                typename shared_ptr_cast_traits<Other>::virtual_type>(obj);
+            using namespace boost::openmethod::detail;
+
+            if constexpr (requires_dynamic_cast<Class*, Other>) {
+                return std::dynamic_pointer_cast<
+                    typename shared_ptr_cast_traits<Other>::virtual_type>(obj);
+            } else {
+                return std::static_pointer_cast<
+                    typename shared_ptr_cast_traits<Other>::virtual_type>(obj);
+            }
         }
     }
 };

include/boost/openmethod/macros.hpp

@@ -62,8 +62,6 @@ struct va_args<ReturnType> {
         ::boost::openmethod::detail::va_args<__VA_ARGS__>::registry>
 
 #define BOOST_OPENMETHOD(NAME, ARGS, ...)                                      \
-    template<typename...>                                                      \
-    struct BOOST_OPENMETHOD_OVERRIDERS(NAME);                                  \
     struct BOOST_OPENMETHOD_ID(NAME);                                          \
     template<typename... ForwarderParameters>                                  \
     typename ::boost::openmethod::detail::enable_forwarder<                    \
@@ -79,7 +77,9 @@ struct va_args<ReturnType> {
             ForwarderParameters...>::type {                                    \
         return BOOST_OPENMETHOD_TYPE(NAME, ARGS, __VA_ARGS__)::fn(             \
             std::forward<ForwarderParameters>(args)...);                       \
-    }
+    }                                                                          \
+    template<typename...>                                                      \
+    struct BOOST_OPENMETHOD_OVERRIDERS(NAME)
 
 #define BOOST_OPENMETHOD_DETAIL_LOCATE_METHOD(NAME, ARGS)                      \
     template<typename T>                                                       \
@@ -88,7 +88,7 @@ struct va_args<ReturnType> {
     struct boost_openmethod_detail_locate_method_aux<void(A...)> {             \
         using type =                                                           \
             decltype(BOOST_OPENMETHOD_GUIDE(NAME)(std::declval<A>()...));      \
-    };
+    }
 
 #define BOOST_OPENMETHOD_DECLARE_OVERRIDER(NAME, ARGS, ...)                    \
     template<typename...>                                                      \
@@ -136,6 +136,6 @@ struct va_args<ReturnType> {
         -> boost::mp11::mp_back<boost::mp11::mp_list<__VA_ARGS__>>
 
 #define BOOST_OPENMETHOD_CLASSES(...)                                          \
-    BOOST_OPENMETHOD_REGISTER(::boost::openmethod::use_classes<__VA_ARGS__>);
+    BOOST_OPENMETHOD_REGISTER(::boost::openmethod::use_classes<__VA_ARGS__>)
 
 #endif

include/boost/openmethod/policies/vptr_vector.hpp

@@ -183,7 +183,7 @@ struct vptr_vector : vptr {
             } else {
                 detail::vptr_vector_vptrs<Registry>.clear();
             }
-        };
+        }
     };
 };
 

include/boost/openmethod/preamble.hpp

@@ -9,6 +9,7 @@
 #include <stdlib.h>
 #include <vector>
 #include <cstdint>
+#include <string_view>
 
 #ifdef _MSC_VER
 #pragma warning(push)

index.html

@@ -7,10 +7,10 @@ file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 
 <html>
 <head>
-    <meta http-equiv="refresh" content="0; URL=doc/html/index.html">
+    <meta http-equiv="refresh" content="0; URL=doc/html/openmethod/index.html">
 </head>
 <body>
 Automatic redirection failed, please go to
-<a href="doc/html/index.html">doc/html/index.html</a>
+<a href="doc/html/openmethod/index.html">doc/html/openmethod/index.html</a>
 </body>
 </html>

meta/libraries.json

@@ -7,7 +7,7 @@
     "maintainers": [
         "Jean-Louis Leroy"
     ],
-    "description": "Open-methods for C++17 and above.",
+    "description": "Open-methods are free-standing functions that work like virtual functions: they select the b​est overrider from a set, depending on the dynamic type of their arguments. This makes it possible to add polymorphic operations to existing classes, without modifying them. They make patterns like Visitor unnecessary.",
     "category": [
         "Emulation", "Programming"
     ],

test/test_dispatch_intrusive_ptr.cpp

@@ -0,0 +1,169 @@
+// Copyright (c) 2018-2025 Jean-Louis Leroy
+// Distributed under the Boost Software License, Version 1.0.
+// See accompanying file LICENSE_1_0.txt
+// or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+#include <iostream>
+#include <stdexcept>
+#include <string>
+#include <type_traits>
+#include <any>
+
+#include <boost/openmethod.hpp>
+#include <boost/openmethod/interop/boost_intrusive_ptr.hpp>
+#include <boost/openmethod/initialize.hpp>
+#include <boost/smart_ptr/intrusive_ptr.hpp>
+#include <boost/smart_ptr/intrusive_ref_counter.hpp>
+
+#define BOOST_TEST_MODULE openmethod
+#include <boost/test/unit_test.hpp>
+
+using namespace boost::openmethod;
+
+#define MAKE_CLASSES()                                                         \
+    struct Animal : boost::intrusive_ref_counter<Animal> {                     \
+        explicit Animal(std::string str) {                                     \
+            name = std::move(str);                                             \
+        }                                                                      \
+                                                                               \
+        Animal(const Animal&) = delete;                                        \
+        Animal(Animal&&) = default;                                            \
+        virtual ~Animal() = default;                                           \
+                                                                               \
+        std::string name;                                                      \
+    };                                                                         \
+                                                                               \
+    struct Dog : Animal {                                                      \
+        using Animal::Animal;                                                  \
+    };                                                                         \
+                                                                               \
+    struct Cat : virtual Animal {                                              \
+        using Animal::Animal;                                                  \
+    };                                                                         \
+                                                                               \
+    BOOST_OPENMETHOD_CLASSES(Animal, Dog, Cat);
+
+namespace BOOST_OPENMETHOD_GENSYM {
+
+// -----------------------------------------------------------------------------
+// pass virtual args by shared_ptr by value
+
+MAKE_CLASSES();
+
+BOOST_OPENMETHOD(
+    name, (virtual_<boost::intrusive_ptr<const Animal>>), std::string);
+
+BOOST_OPENMETHOD_OVERRIDE(
+    name, (boost::intrusive_ptr<const Cat> cat), std::string) {
+    return cat->name + " the cat";
+}
+
+BOOST_OPENMETHOD_OVERRIDE(
+    name, (boost::intrusive_ptr<const Dog> dog), std::string) {
+    return dog->name + " the dog";
+}
+
+BOOST_AUTO_TEST_CASE(intrusive_ptr_by_value) {
+    initialize();
+
+    auto spot = boost::intrusive_ptr<const Dog>(new Dog("Spot"));
+    BOOST_TEST(name(spot) == "Spot the dog");
+
+    auto felix = boost::intrusive_ptr<const Cat>(new Cat("Felix"));
+    BOOST_TEST(name(felix) == "Felix the cat");
+}
+} // namespace BOOST_OPENMETHOD_GENSYM
+
+namespace BOOST_OPENMETHOD_GENSYM {
+
+// -----------------------------------------------------------------------------
+// pass virtual args by shared_ptr by const&
+
+MAKE_CLASSES();
+
+BOOST_OPENMETHOD(
+    name, (virtual_<const boost::intrusive_ptr<const Animal>&>), std::string);
+
+BOOST_OPENMETHOD_OVERRIDE(
+    name, (const boost::intrusive_ptr<const Cat>& cat), std::string) {
+    return cat->name + " the cat";
+}
+
+BOOST_OPENMETHOD_OVERRIDE(
+    name, (const boost::intrusive_ptr<const Dog>& dog), std::string) {
+    return dog->name + " the dog";
+}
+
+BOOST_AUTO_TEST_CASE(intrusive_ptr_by_const_ref) {
+    initialize();
+
+    auto spot = boost::intrusive_ptr<const Dog>(new Dog("Spot"));
+    BOOST_TEST(name(spot) == "Spot the dog");
+
+    auto felix = boost::intrusive_ptr<const Cat>(new Cat("Felix"));
+    BOOST_TEST(name(felix) == "Felix the cat");
+}
+} // namespace BOOST_OPENMETHOD_GENSYM
+
+namespace BOOST_OPENMETHOD_GENSYM {
+
+// -----------------------------------------------------------------------------
+// virtual_ptr<intrusive_ptr> by value
+
+MAKE_CLASSES();
+
+BOOST_OPENMETHOD(
+    name, (boost_intrusive_virtual_ptr<const Animal>), std::string);
+
+BOOST_OPENMETHOD_OVERRIDE(
+    name, (boost_intrusive_virtual_ptr<const Cat> cat), std::string) {
+    return cat->name + " the cat";
+}
+
+BOOST_OPENMETHOD_OVERRIDE(
+    name, (boost_intrusive_virtual_ptr<const Dog> dog), std::string) {
+    return dog->name + " the dog";
+}
+
+BOOST_AUTO_TEST_CASE(intrusive_virtual_ptr_by_value) {
+    initialize();
+
+    auto spot = make_boost_intrusive_virtual<const Dog>("Spot");
+    BOOST_TEST(name(spot) == "Spot the dog");
+
+    auto felix = make_boost_intrusive_virtual<const Cat>("Felix");
+    BOOST_TEST(name(felix) == "Felix the cat");
+}
+} // namespace BOOST_OPENMETHOD_GENSYM
+
+
+namespace BOOST_OPENMETHOD_GENSYM {
+
+// -----------------------------------------------------------------------------
+// virtual_ptr<intrusive_ptr> by const&
+
+MAKE_CLASSES();
+
+BOOST_OPENMETHOD(
+    name, (const boost_intrusive_virtual_ptr<const Animal>&), std::string);
+
+BOOST_OPENMETHOD_OVERRIDE(
+    name, (const boost_intrusive_virtual_ptr<const Cat>& cat), std::string) {
+    return cat->name + " the cat";
+}
+
+BOOST_OPENMETHOD_OVERRIDE(
+    name, (const boost_intrusive_virtual_ptr<const Dog>& dog), std::string) {
+    return dog->name + " the dog";
+}
+
+BOOST_AUTO_TEST_CASE(intrusive_virtual_ptr_by_const_ref) {
+    initialize();
+
+    auto spot = make_boost_intrusive_virtual<const Dog>("Spot");
+    BOOST_TEST(name(spot) == "Spot the dog");
+
+    auto felix = make_boost_intrusive_virtual<const Cat>("Felix");
+    BOOST_TEST(name(felix) == "Felix the cat");
+}
+} // namespace BOOST_OPENMETHOD_GENSYM

test/test_smart_virtual_ptr_value_semantics.cpp

@@ -0,0 +1,443 @@
+// Copyright (c) 2018-2025 Jean-Louis Leroy
+// Distributed under the Boost Software License, Version 1.0.
+// See accompanying file LICENSE_1_0.txt
+// or q at http://www.boost.org/LICENSE_1_0.txt)
+
+#include <boost/openmethod/interop/std_shared_ptr.hpp>
+#include <boost/openmethod/interop/boost_intrusive_ptr.hpp>
+
+#define BOOST_TEST_MODULE openmethod
+#include <boost/test/unit_test.hpp>
+
+#include <boost/utility/identity_type.hpp>
+
+#include "test_virtual_ptr_value_semantics.hpp"
+
+#include <memory>
+
+#ifdef BOOST_GCC
+#pragma GCC diagnostic ignored "-Wunused-local-typedefs"
+#endif
+
+#ifdef __clang__
+#pragma clang diagnostic ignored "-Wunused-local-typedefs"
+#endif
+
+struct using_shared_ptr {
+    template<class Class>
+    using ptr = std::shared_ptr<Class>;
+
+    template<class Class>
+    using virtual_ptr = shared_virtual_ptr<Class>;
+
+    template<class Class, class... Args>
+    static decltype(auto) make(Args&&... args) {
+        return std::make_shared<Class>(std::forward<Args>(args)...);
+    }
+
+    template<class Class, class... Args>
+    static decltype(auto) make_virtual(Args&&... args) {
+        return make_shared_virtual<Class>(std::forward<Args>(args)...);
+    }
+
+    static bool cast_moves() {
+        initialize();
+
+        ptr<Animal> animal = make<Dog>();
+        (void)std::static_pointer_cast<Dog>(animal);
+
+        return animal.get() == nullptr;
+    }
+};
+
+struct using_boost_intrusive_ptr {
+    template<class Class>
+    using ptr = boost::intrusive_ptr<Class>;
+
+    template<class Class>
+    using virtual_ptr = boost_intrusive_virtual_ptr<Class>;
+
+    template<class Class, class... Args>
+    static auto make(Args&&... args) {
+        return boost::intrusive_ptr<Class>(
+            new Class(std::forward<Args>(args)...));
+    }
+
+    template<class Class, class... Args>
+    static auto make_virtual(Args&&... args) {
+        return make_boost_intrusive_virtual<Class>(std::forward<Args>(args)...);
+    }
+
+    static bool cast_moves() {
+        return false;
+    }
+};
+
+using smart_pointers =
+    boost::mp11::mp_list<using_shared_ptr, using_boost_intrusive_ptr>;
+
+#define USING_DECLARATIONS                                                     \
+    using animal_ptr = typename smart::template ptr<Animal>;                   \
+    using const_animal_ptr = typename smart::template ptr<const Animal>;       \
+    using animal_virtual_ptr = typename smart::template virtual_ptr<Animal>;   \
+    using const_animal_virtual_ptr =                                           \
+        typename smart::template virtual_ptr<const Animal>;                    \
+    using dog_ptr = typename smart::template ptr<Dog>;                         \
+    using const_dog_ptr = typename smart::template ptr<const Dog>;             \
+    using dog_virtual_ptr = typename smart::template virtual_ptr<Dog>;         \
+    using const_dog_virtual_ptr =                                              \
+        typename smart::template virtual_ptr<const Dog>;                       \
+    using cat_ptr = typename smart::template ptr<Cat>;                         \
+    using const_cat_ptr = typename smart::template ptr<const Cat>;             \
+    using cat_virtual_ptr = typename smart::template virtual_ptr<Cat>;         \
+    using const_cat_virtual_ptr =                                              \
+        typename smart::template virtual_ptr<const Cat>;
+
+BOOST_AUTO_TEST_CASE_TEMPLATE(
+    smart_pointer_value_semantics, smart, smart_pointers) {
+    USING_DECLARATIONS;
+
+    static_assert(SameSmartPtr<animal_ptr, dog_ptr, default_registry>);
+    static_assert(
+        !SameSmartPtr<animal_ptr, std::unique_ptr<Dog>, default_registry>);
+    static_assert(
+        std::is_same_v<typename animal_virtual_ptr::element_type, Animal>);
+    static_assert(std::is_same_v<
+                  decltype(std::declval<animal_virtual_ptr>().get()), Animal*>);
+    static_assert(IsSmartPtr<animal_ptr, default_registry>);
+    static_assert(IsSmartPtr<const_animal_ptr, default_registry>);
+    static_assert(
+        std::is_same_v<decltype(*std::declval<animal_virtual_ptr>()), Animal&>);
+
+    initialize();
+
+    // construction and assignment from a plain pointer or reference is not
+    // allowed
+
+    static_assert(!construct_assign_ok<dog_virtual_ptr, Dog>);
+    static_assert(!construct_assign_ok<dog_virtual_ptr, Dog&&>);
+    static_assert(!construct_assign_ok<dog_virtual_ptr, const Dog&>);
+    static_assert(!construct_assign_ok<dog_virtual_ptr, const Dog*>);
+
+    // -------------------------------------------------------------------------
+    // construction and assignment from plain references and pointers
+
+    {
+        dog_virtual_ptr p{nullptr};
+        BOOST_TEST(p.get() == nullptr);
+        BOOST_TEST(p.vptr() == nullptr);
+    }
+
+    {
+        auto snoopy = smart::template make<Dog>();
+        dog_virtual_ptr p(snoopy);
+        BOOST_TEST(p.get() == snoopy.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Dog>);
+
+        p = *&p;
+        BOOST_TEST(p.get() == snoopy.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Dog>);
+
+        auto hector = smart::template make<Dog>();
+        p = hector;
+        BOOST_TEST(p.get() == hector.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Dog>);
+    }
+
+    {
+        auto snoopy = smart::template make<Dog>();
+        animal_virtual_ptr p(snoopy);
+        BOOST_TEST(p.get() == snoopy.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Dog>);
+
+        auto felix = smart::template make<Cat>();
+        p = felix;
+        BOOST_TEST(p.get() == felix.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Cat>);
+    }
+
+    {
+        auto snoopy = smart::template make<const Dog>();
+        const_dog_virtual_ptr p(snoopy);
+        BOOST_TEST(p.get() == snoopy.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Dog>);
+
+        auto hector = smart::template make<const Dog>();
+        p = hector;
+        BOOST_TEST(p.get() == hector.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Dog>);
+    }
+
+    {
+        const auto snoopy = smart::template make<const Dog>();
+        const_animal_virtual_ptr p(snoopy);
+        BOOST_TEST(p.get() == snoopy.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Dog>);
+
+        auto felix = smart::template make<const Cat>();
+        p = felix;
+        BOOST_TEST(p.get() == felix.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Cat>);
+    }
+
+    {
+        auto snoopy = smart::template make<Dog>();
+        dog_virtual_ptr p(snoopy);
+        BOOST_TEST(p.get() == snoopy.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Dog>);
+
+        auto hector = smart::template make<Dog>();
+        p = hector;
+        BOOST_TEST(p.get() == hector.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Dog>);
+    }
+
+    {
+        auto snoopy = smart::template make<Dog>();
+        animal_virtual_ptr p(snoopy);
+        BOOST_TEST(p.get() == snoopy.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Dog>);
+
+        auto felix = smart::template make<Cat>();
+        p = felix;
+        BOOST_TEST(p.get() == felix.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Cat>);
+    }
+
+    {
+        auto snoopy = smart::template make<const Dog>();
+        const_dog_virtual_ptr p(snoopy);
+        BOOST_TEST(p.get() == snoopy.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Dog>);
+
+        auto hector = smart::template make<const Dog>();
+        p = hector;
+        BOOST_TEST(p.get() == hector.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Dog>);
+    }
+
+    {
+        auto snoopy = smart::template make<const Dog>();
+        const_animal_virtual_ptr p(snoopy);
+        BOOST_TEST(p.get() == snoopy.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Dog>);
+
+        auto felix = smart::template make<const Cat>();
+        p = felix;
+        BOOST_TEST(p.get() == felix.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Cat>);
+    }
+
+    // dog_virtual_ptr p{Dog()};
+    static_assert(!construct_assign_ok<dog_virtual_ptr, Dog&&>);
+
+    // -------------------------------------------------------------------------
+    // construction and assignment from other shared_virtual_ptr
+
+    {
+        // dog_virtual_ptr(const dog_virtual_ptr&)
+        auto snoopy = smart::template make<Dog>();
+        const dog_virtual_ptr p(snoopy);
+        dog_virtual_ptr q(p);
+        BOOST_TEST(q.get() == snoopy.get());
+        BOOST_TEST(q.vptr() == default_registry::template static_vptr<Dog>);
+    }
+
+    {
+        // dog_virtual_ptr(dog_virtual_ptr&)
+        auto snoopy = smart::template make<Dog>();
+        dog_virtual_ptr p(snoopy);
+        dog_virtual_ptr q(p);
+        BOOST_TEST(q.get() == snoopy.get());
+        BOOST_TEST(q.vptr() == default_registry::template static_vptr<Dog>);
+    }
+
+    {
+        // dog_virtual_ptr(dog_virtual_ptr&&)
+        auto snoopy = smart::template make<Dog>();
+        dog_virtual_ptr p(snoopy);
+        dog_virtual_ptr q(std::move(p));
+        BOOST_TEST(q.get() == snoopy.get());
+        BOOST_TEST(q.vptr() == default_registry::template static_vptr<Dog>);
+        BOOST_TEST(p.get() == nullptr);
+        BOOST_TEST(p.vptr() == nullptr);
+    }
+
+    {
+        // animal_virtual_ptr(const dog_virtual_ptr&)
+        auto snoopy = smart::template make<Dog>();
+        const dog_virtual_ptr p(snoopy);
+        animal_virtual_ptr base(p);
+        BOOST_TEST(base.get() == snoopy.get());
+        BOOST_TEST(base.vptr() == default_registry::template static_vptr<Dog>);
+    }
+
+    {
+        // shared_virtual_ptr<const Dog>(const dog_virtual_ptr&)
+        auto snoopy = smart::template make<Dog>();
+        const dog_virtual_ptr p(snoopy);
+        const_dog_virtual_ptr const_q(p);
+        BOOST_TEST(const_q.get() == snoopy.get());
+        BOOST_TEST(
+            const_q.vptr() == default_registry::template static_vptr<Dog>);
+    }
+
+    {
+        // shared_virtual_ptr<const Animal>(const dog_virtual_ptr&)
+        auto snoopy = smart::template make<Dog>();
+        const dog_virtual_ptr p(snoopy);
+        const_animal_virtual_ptr const_base_q(p);
+        BOOST_TEST(const_base_q.get() == snoopy.get());
+        BOOST_TEST(
+            const_base_q.vptr() == default_registry::template static_vptr<Dog>);
+    }
+
+    {
+        // dog_virtual_ptr()
+        dog_virtual_ptr p{nullptr};
+        BOOST_TEST(p.get() == nullptr);
+        BOOST_TEST(p.vptr() == nullptr);
+    }
+
+    {
+        dog_virtual_ptr p{dog_ptr()};
+        BOOST_TEST(p.get() == nullptr);
+        BOOST_TEST(p.vptr() == nullptr);
+    }
+
+    // -------------------------------------------------------------------------
+    // assignment
+
+    {
+        dog_virtual_ptr p;
+        auto snoopy = smart::template make<Dog>();
+        p = snoopy;
+        BOOST_TEST(p.get() == snoopy.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Dog>);
+    }
+
+    {
+        dog_virtual_ptr p;
+        auto snoopy = smart::template make<Dog>();
+        p = snoopy;
+        BOOST_TEST(p.get() == snoopy.get());
+        BOOST_TEST(p.vptr() == default_registry::template static_vptr<Dog>);
+    }
+
+    {
+        auto p = smart::template make_virtual<Dog>();
+        p = nullptr;
+        BOOST_TEST(p.get() == nullptr);
+        BOOST_TEST(p.vptr() == nullptr);
+    }
+
+    {
+        auto p = smart::template make_virtual<Dog>();
+        p = dog_ptr();
+        BOOST_TEST(p.get() == nullptr);
+        BOOST_TEST(p.vptr() == nullptr);
+    }
+
+    static_assert(!construct_assign_ok<dog_virtual_ptr, const Dog&>);
+    static_assert(!construct_assign_ok<dog_virtual_ptr, const Dog*>);
+}
+
+BOOST_AUTO_TEST_CASE_TEMPLATE(cast_smart_pointer_value, smart, smart_pointers) {
+    USING_DECLARATIONS;
+
+    initialize();
+
+    animal_ptr animal = smart::template make<Dog>();
+    dog_ptr dog =
+        virtual_traits<animal_ptr, default_registry>::template cast<dog_ptr>(
+            animal);
+    BOOST_TEST(dog.get() == animal.get());
+}
+
+BOOST_AUTO_TEST_CASE_TEMPLATE(
+    cast_smart_ptr_lvalue_reference, smart, smart_pointers) {
+    USING_DECLARATIONS;
+
+    initialize();
+
+    animal_ptr animal = smart::template make<Dog>();
+    dog_ptr dog =
+        virtual_traits<const animal_ptr&, default_registry>::template cast<
+            const dog_ptr&>(animal);
+    BOOST_TEST(dog.get() == animal.get());
+
+    dog_ptr dog2 = virtual_traits<
+        const dog_ptr&, default_registry>::template cast<const dog_ptr&>(dog);
+    BOOST_TEST(dog2.get() == dog.get());
+}
+
+BOOST_AUTO_TEST_CASE_TEMPLATE(
+    cast_smart_ptr_xvalue_reference, smart, smart_pointers) {
+    USING_DECLARATIONS;
+
+    initialize();
+
+    animal_ptr animal = smart::template make<Dog>();
+    auto p = animal.get();
+    auto dog =
+        virtual_traits<animal_ptr, default_registry>::template cast<dog_ptr>(
+            std::move(animal));
+    BOOST_TEST(dog.get() == p);
+
+    if (smart::cast_moves()) {
+        BOOST_TEST(animal.get() == nullptr);
+    }
+}
+
+BOOST_AUTO_TEST_CASE_TEMPLATE(
+    cast_shared_virtual_ptr_value, smart, smart_pointers) {
+    USING_DECLARATIONS;
+
+    initialize();
+
+    animal_virtual_ptr base = smart::template make<Dog>();
+    auto derived = virtual_traits<
+        animal_virtual_ptr, default_registry>::template cast<dog_ptr>(base);
+    BOOST_TEST(derived.get() == base.get());
+    BOOST_TEST(base.vptr() == default_registry::static_vptr<Dog>);
+    BOOST_TEST(derived.vptr() == default_registry::static_vptr<Dog>);
+}
+
+BOOST_AUTO_TEST_CASE_TEMPLATE(
+    cast_shared_virtual_ptr_lvalue_reference, smart, smart_pointers) {
+    USING_DECLARATIONS;
+
+    initialize();
+
+    animal_virtual_ptr base = smart::template make<Dog>();
+    auto derived = virtual_traits<const animal_virtual_ptr&, default_registry>::
+        template cast<const dog_virtual_ptr&>(base);
+    BOOST_TEST(derived.get() == base.get());
+    BOOST_TEST(base.vptr() == default_registry::static_vptr<Dog>);
+    BOOST_TEST(derived.vptr() == default_registry::static_vptr<Dog>);
+}
+
+BOOST_AUTO_TEST_CASE_TEMPLATE(
+    cast_shared_virtual_ptr_xvalue_reference, smart, smart_pointers) {
+    USING_DECLARATIONS;
+
+    initialize();
+
+    animal_virtual_ptr base = smart::template make<Dog>();
+    auto p = base.get();
+    auto derived =
+        virtual_traits<animal_virtual_ptr, default_registry>::template cast<
+            dog_virtual_ptr>(std::move(base));
+    BOOST_TEST(derived.get() == p);
+    BOOST_TEST(derived.vptr() == default_registry::static_vptr<Dog>);
+
+    if (smart::cast_moves()) {
+        BOOST_TEST(base.get() == nullptr);
+    }
+}
+
+template struct check_illegal_smart_ops<
+    std::shared_ptr, std::unique_ptr, direct_vector>;
+
+template struct check_illegal_smart_ops<
+    boost::intrusive_ptr, std::unique_ptr, direct_vector>;

test/test_unique_virtual_ptr_value_semantics.cpp

@@ -116,6 +116,7 @@ BOOST_AUTO_TEST_CASE_TEMPLATE(
         unique_virtual_ptr<Dog, Registry> p(std::make_unique<Dog>());
         auto dog = p.get();
         unique_virtual_ptr<Dog, Registry> q(std::move(p));
+        // coverity[use_after_move]
         BOOST_TEST(q.get() == dog);
         BOOST_TEST(q.vptr() == Registry::template static_vptr<Dog>);
         BOOST_TEST(p.get() == nullptr);
@@ -127,6 +128,7 @@ BOOST_AUTO_TEST_CASE_TEMPLATE(
         unique_virtual_ptr<Dog, Registry> p(std::make_unique<Dog>());
         auto dog = p.get();
         unique_virtual_ptr<Animal, Registry> q(std::move(p));
+        // coverity[use_after_move]
         BOOST_TEST(q.get() == dog);
         BOOST_TEST(q.vptr() == Registry::template static_vptr<Dog>);
         BOOST_TEST(p.get() == nullptr);

test/test_virtual_ptr_value_semantics.cpp

@@ -168,6 +168,7 @@ BOOST_AUTO_TEST_CASE_TEMPLATE(
         Dog snoopy;
         virtual_ptr<Dog, Registry> p(snoopy);
         virtual_ptr<Dog, Registry> q(std::move(p));
+        // coverity[use_after_move]
         BOOST_TEST(q.get() == &snoopy);
         BOOST_TEST(q.vptr() == Registry::template static_vptr<Dog>);
         BOOST_TEST(p.get() == &snoopy);

test/test_virtual_ptr_value_semantics.hpp

@@ -6,10 +6,16 @@
 #ifndef TEST_VIRTUAL_PTR_VALUE_SEMANTICS_HPP
 #define TEST_VIRTUAL_PTR_VALUE_SEMANTICS_HPP
 
+#include <type_traits>
+#include <boost/mp11.hpp>
 #include <boost/openmethod.hpp>
-#include <boost/openmethod/policies/vptr_map.hpp>
 #include <boost/openmethod/initialize.hpp>
+#include <boost/openmethod/policies/vptr_map.hpp>
+#include <boost/openmethod/interop/std_shared_ptr.hpp>
+#include <boost/openmethod/interop/boost_intrusive_ptr.hpp>
 #include <boost/openmethod/interop/std_unique_ptr.hpp>
+#include <boost/smart_ptr/intrusive_ptr.hpp>
+#include <boost/smart_ptr/intrusive_ref_counter.hpp>
 
 #include "test_util.hpp"
 
@@ -19,7 +25,7 @@ using namespace boost::openmethod;
 using namespace policies;
 using namespace detail;
 
-struct Animal {
+struct Animal : boost::intrusive_ref_counter<Animal> {
     virtual ~Animal() {
     }
 
@@ -31,6 +37,12 @@ struct Cat : virtual Animal {};
 
 struct Dog : Animal {};
 
+BOOST_OPENMETHOD_CLASSES(Animal, Cat, Dog);
+
+struct id;
+// without following line, no methods, no v-tables
+auto instantiate_a_method = &method<id, auto(virtual_ptr<Animal>)->void>::fn;
+
 template<class Left, class Right>
 constexpr bool construct_assign_ok =
     std::is_constructible_v<Left, Right> && std::is_assignable_v<Left, Right>;