From fd8265e28d019914b3e654b63a0552ec0b44efea Mon Sep 17 00:00:00 2001 From: Dustin Spicuzza Date: Wed, 26 Jan 2022 22:02:49 -0500 Subject: [PATCH] Fix smart_holder multiple inheritance tests (#3635) The original pybind11 holder supported multiple inheritance by recursively creating type casters until it finds one for the source type, then converting each value in turn to the next type via typeinfo->implicit_cast The smart_holder only stored the last implicit_cast, which was incorrect. This commit changes it to create a list of implicit_cast functions that are appended to during the recursive type caster creation, and when the time comes to cast to the destination type, it calls all of them in the correct order. --- .../pybind11/detail/smart_holder_type_casters.h | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/include/pybind11/detail/smart_holder_type_casters.h b/include/pybind11/detail/smart_holder_type_casters.h index c76ce9f4a..9ff79e7b1 100644 --- a/include/pybind11/detail/smart_holder_type_casters.h +++ b/include/pybind11/detail/smart_holder_type_casters.h @@ -99,7 +99,9 @@ public: } loaded_v_h = sub_caster.loaded_v_h; loaded_v_h_cpptype = cast.first; - implicit_cast = cast.second; + // the sub_caster is being discarded, so steal its vector + implicit_casts = std::move(sub_caster.implicit_casts); + implicit_casts.emplace_back(cast.second); return true; } } @@ -180,7 +182,7 @@ public: } loaded_v_h = foreign_loader->loaded_v_h; loaded_v_h_cpptype = foreign_loader->loaded_v_h_cpptype; - implicit_cast = foreign_loader->implicit_cast; + implicit_casts = foreign_loader->implicit_casts; // SMART_HOLDER_WIP: should this be a copy or move? return true; } return false; @@ -286,7 +288,7 @@ public: void *unowned_void_ptr_from_direct_conversion = nullptr; void *unowned_void_ptr_from_void_ptr_capsule = nullptr; const std::type_info *loaded_v_h_cpptype = nullptr; - void *(*implicit_cast)(void *) = nullptr; + std::vector implicit_casts; value_and_holder loaded_v_h; bool reinterpret_cast_deemed_ok = false; // Magic number intentionally hard-coded, to guard against class_ holder mixups. @@ -567,8 +569,10 @@ private: T *convert_type(void *void_ptr) const { if (void_ptr != nullptr && load_impl.loaded_v_h_cpptype != nullptr - && !load_impl.reinterpret_cast_deemed_ok && load_impl.implicit_cast != nullptr) { - void_ptr = load_impl.implicit_cast(void_ptr); + && !load_impl.reinterpret_cast_deemed_ok && !load_impl.implicit_casts.empty()) { + for (auto implicit_cast: load_impl.implicit_casts) { + void_ptr = implicit_cast(void_ptr); + } } return static_cast(void_ptr); }