| 210 | /// Special internal constructor for functors, lambda functions, etc. |
| 211 | template <typename Func, typename Return, typename... Args, typename... Extra> |
| 212 | void initialize(Func &&f, Return (*)(Args...), const Extra &...extra) { |
| 213 | using namespace detail; |
| 214 | struct capture { |
| 215 | remove_reference_t<Func> f; |
| 216 | }; |
| 217 | |
| 218 | /* Store the function including any extra state it might have (e.g. a lambda capture |
| 219 | * object) */ |
| 220 | // The unique_ptr makes sure nothing is leaked in case of an exception. |
| 221 | auto unique_rec = make_function_record(); |
| 222 | auto *rec = unique_rec.get(); |
| 223 | |
| 224 | /* Store the capture object directly in the function record if there is enough space */ |
| 225 | if (sizeof(capture) <= sizeof(rec->data)) { |
| 226 | /* Without these pragmas, GCC warns that there might not be |
| 227 | enough space to use the placement new operator. However, the |
| 228 | 'if' statement above ensures that this is the case. */ |
| 229 | PYBIND11_WARNING_PUSH |
| 230 | |
| 231 | #if defined(__GNUG__) && __GNUC__ >= 6 |
| 232 | PYBIND11_WARNING_DISABLE_GCC("-Wplacement-new") |
| 233 | #endif |
| 234 | |
| 235 | new ((capture *) &rec->data) capture{std::forward<Func>(f)}; |
| 236 | |
| 237 | #if !PYBIND11_HAS_STD_LAUNDER |
| 238 | PYBIND11_WARNING_DISABLE_GCC("-Wstrict-aliasing") |
| 239 | #endif |
| 240 | |
| 241 | // UB without std::launder, but without breaking ABI and/or |
| 242 | // a significant refactoring it's "impossible" to solve. |
| 243 | if (!std::is_trivially_destructible<capture>::value) { |
| 244 | rec->free_data = [](function_record *r) { |
| 245 | auto data = PYBIND11_STD_LAUNDER((capture *) &r->data); |
| 246 | (void) data; |
| 247 | data->~capture(); |
| 248 | }; |
| 249 | } |
| 250 | PYBIND11_WARNING_POP |
| 251 | } else { |
| 252 | rec->data[0] = new capture{std::forward<Func>(f)}; |
| 253 | rec->free_data = [](function_record *r) { delete ((capture *) r->data[0]); }; |
| 254 | } |
| 255 | |
| 256 | /* Type casters for the function arguments and return value */ |
| 257 | using cast_in = argument_loader<Args...>; |
| 258 | using cast_out |
| 259 | = make_caster<conditional_t<std::is_void<Return>::value, void_type, Return>>; |
| 260 | |
| 261 | static_assert( |
| 262 | expected_num_args<Extra...>( |
| 263 | sizeof...(Args), cast_in::args_pos >= 0, cast_in::has_kwargs), |
| 264 | "The number of argument annotations does not match the number of function arguments"); |
| 265 | |
| 266 | /* Dispatch code which converts function arguments and performs the actual function call */ |
| 267 | rec->impl = [](function_call &call) -> handle { |
| 268 | cast_in args_converter; |
| 269 | |