/* * yosys -- Yosys Open SYnthesis Suite * * Copyright (C) 2012 Clifford Wolf * * Permission to use, copy, modify, and/or distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. * */ #include "kernel/register.h" #include "kernel/log.h" #include #include YOSYS_NAMESPACE_BEGIN extern void proc_clean_case(RTLIL::CaseRule *cs, bool &did_something, int &count, int max_depth); YOSYS_NAMESPACE_END USING_YOSYS_NAMESPACE PRIVATE_NAMESPACE_BEGIN void proc_clean_switch(RTLIL::SwitchRule *sw, RTLIL::CaseRule *parent, bool &did_something, int &count, int max_depth) { if (sw->signal.size() > 0 && sw->signal.is_fully_const()) { int found_matching_case_idx = -1; for (int i = 0; i < int(sw->cases.size()) && found_matching_case_idx < 0; i++) { RTLIL::CaseRule *cs = sw->cases[i]; if (cs->compare.size() == 0) break; for (int j = 0; j < int(cs->compare.size()); j++) { RTLIL::SigSpec &val = cs->compare[j]; if (!val.is_fully_const()) continue; if (val == sw->signal) { cs->compare.clear(); found_matching_case_idx = i; break; } else cs->compare.erase(cs->compare.begin()+(j--)); } if (cs->compare.size() == 0 && found_matching_case_idx < 0) { sw->cases.erase(sw->cases.begin()+(i--)); delete cs; } } while (found_matching_case_idx >= 0 && int(sw->cases.size()) > found_matching_case_idx+1) { delete sw->cases.back(); sw->cases.pop_back(); } if (found_matching_case_idx == 0) sw->signal = RTLIL::SigSpec(); } if (parent->switches.front() == sw && sw->cases.size() == 1 && (sw->signal.size() == 0 || sw->cases[0]->compare.empty())) { did_something = true; for (auto &action : sw->cases[0]->actions) parent->actions.push_back(action); for (auto sw2 : sw->cases[0]->switches) parent->switches.push_back(sw2); sw->cases[0]->switches.clear(); delete sw->cases[0]; sw->cases.clear(); } else { bool all_fully_def = true; for (auto cs : sw->cases) { if (max_depth != 0) proc_clean_case(cs, did_something, count, max_depth-1); int size = 0; for (auto cmp : cs->compare) { size += cmp.size(); if (!cmp.is_fully_def()) all_fully_def = false; } if (sw->signal.size() != size) all_fully_def = false; } if (all_fully_def) { for (auto cs = sw->cases.begin(); cs != sw->cases.end();) { if ((*cs)->empty()) { did_something = true; delete *cs; cs = sw->cases.erase(cs); } else ++cs; } } else { while (!sw->cases.empty() && sw->cases.back()->empty()) { did_something = true; delete sw->cases.back(); sw->cases.pop_back(); } } } } PRIVATE_NAMESPACE_END YOSYS_NAMESPACE_BEGIN void proc_clean_case(RTLIL::CaseRule *cs, bool &did_something, int &count, int max_depth) { for (size_t i = 0; i < cs->actions.size(); i++) { if (cs->actions[i].first.size() == 0) { did_something = true; cs->actions.erase(cs->actions.begin() + (i--)); } } for (size_t i = 0; i < cs->switches.size(); i++) { RTLIL::SwitchRule *sw = cs->switches[i]; if (sw->empty()) { cs->switches.erase(cs->switches.begin() + (i--)); did_something = true; delete sw; count++; } else if (max_depth != 0) proc_clean_switch(sw, cs, did_something, count, max_depth-1); } } YOSYS_NAMESPACE_END PRIVATE_NAMESPACE_BEGIN void proc_clean(RTLIL::Module *mod, RTLIL::Process *proc, int &total_count, bool quiet) { int count = 0; bool did_something = true; for (size_t i = 0; i < proc->syncs.size(); i++) { for (size_t j = 0; j < proc->syncs[i]->actions.size(); j++) if (proc->syncs[i]->actions[j].first.size() == 0) proc->syncs[i]->actions.erase(proc->syncs[i]->actions.begin() + (j--)); if (proc->syncs[i]->actions.size() == 0) { delete proc->syncs[i]; proc->syncs.erase(proc->syncs.begin() + (i--)); } } while (did_something) { did_something = false; proc_clean_case(&proc->root_case, did_something, count, -1); } if (count > 0 && !quiet) log("Found and cleaned up %d empty switch%s in `%s.%s'.\n", count, count == 1 ? "" : "es", mod->name.c_str(), proc->name.c_str()); total_count += count; } struct ProcCleanPass : public Pass { ProcCleanPass() : Pass("proc_clean", "remove empty parts of processes") { } void help() YS_OVERRIDE { // |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---| log("\n"); log(" proc_clean [options] [selection]\n"); log("\n"); log(" -quiet\n"); log(" do not print any messages.\n"); log("\n"); log("This pass removes empty parts of processes and ultimately removes a process\n"); log("if it contains only empty structures.\n"); log("\n"); } void execute(std::vector args, RTLIL::Design *design) YS_OVERRIDE { int total_count = 0; bool quiet = false; if (find(args.begin(), args.end(), "-quiet") == args.end()) log_header(design, "Executing PROC_CLEAN pass (remove empty switches from decision trees).\n"); size_t argidx; for (argidx = 1; argidx < args.size(); argidx++) { if (args[argidx] == "-quiet") { quiet = true; continue; } } extra_args(args, argidx, design); for (auto mod : design->modules()) { std::vector delme; if (!design->selected(mod)) continue; for (auto &proc_it : mod->processes) { if (!design->selected(mod, proc_it.second)) continue; proc_clean(mod, proc_it.second, total_count, quiet); if (proc_it.second->syncs.size() == 0 && proc_it.second->root_case.switches.size() == 0 && proc_it.second->root_case.actions.size() == 0) { if (!quiet) log("Removing empty process `%s.%s'.\n", log_id(mod), proc_it.second->name.c_str()); delme.push_back(proc_it.first); } } for (auto &id : delme) { delete mod->processes[id]; mod->processes.erase(id); } } if (!quiet) log("Cleaned up %d empty switch%s.\n", total_count, total_count == 1 ? "" : "es"); } } ProcCleanPass; PRIVATE_NAMESPACE_END 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 
/*
    tests/test_factory_constructors.cpp -- tests construction from a factory function
                                           via py::init_factory()

    Copyright (c) 2017 Jason Rhinelander <jason@imaginary.ca>

    All rights reserved. Use of this source code is governed by a
    BSD-style license that can be found in the LICENSE file.
*/

#include "pybind11_tests.h"
#include "constructor_stats.h"
#include <cmath>
#include <new>

// Classes for testing python construction via C++ factory function:
// Not publicly constructible, copyable, or movable:
class TestFactory1 {
    friend class TestFactoryHelper;
    TestFactory1() : value("(empty)") { print_default_created(this); }
    TestFactory1(int v) : value(std::to_string(v)) { print_created(this, value); }
    TestFactory1(std::string v) : value(std::move(v)) { print_created(this, value); }
    TestFactory1(TestFactory1 &&) = delete;
    TestFactory1(const TestFactory1 &) = delete;
    TestFactory1 &operator=(TestFactory1 &&) = delete;
    TestFactory1 &operator=(const TestFactory1 &) = delete;
public:
    std::string value;
    ~TestFactory1() { print_destroyed(this); }
};
// Non-public construction, but moveable:
class TestFactory2 {
    friend class TestFactoryHelper;
    TestFactory2() : value("(empty2)") { print_default_created(this); }
    TestFactory2(int v) : value(std::to_string(v)) { print_created(this, value); }
    TestFactory2(std::string v) : value(std::move(v)) { print_created(this, value); }
public:
    TestFactory2(TestFactory2 &&m) { value = std::move(m.value); print_move_created(this); }
    TestFactory2 &operator=(TestFactory2 &&m) { value = std::move(m.value); print_move_assigned(this); return *this; }
    std::string value;
    ~TestFactory2() { print_destroyed(this); }
};
// Mixed direct/factory construction:
class TestFactory3 {
protected:
    friend class TestFactoryHelper;
    TestFactory3() : value("(empty3)") { print_default_created(this); }
    TestFactory3(int v) : value(std::to_string(v)) { print_created(this, value); }
public:
    TestFactory3(std::string v) : value(std::move(v)) { print_created(this, value); }
    TestFactory3(TestFactory3 &&m) { value = std::move(m.value); print_move_created(this); }
    TestFactory3 &operator=(TestFactory3 &&m) { value = std::move(m.value); print_move_assigned(this); return *this; }
    std::string value;
    virtual ~TestFactory3() { print_destroyed(this); }
};
// Inheritance test
class TestFactory4 : public TestFactory3 {
public:
    TestFactory4() : TestFactory3() { print_default_created(this); }
    TestFactory4(int v) : TestFactory3(v) { print_created(this, v); }
    ~TestFactory4() override { print_destroyed(this); }
};
// Another class for an invalid downcast test
class TestFactory5 : public TestFactory3 {
public:
    TestFactory5(int i) : TestFactory3(i) { print_created(this, i); }
    ~TestFactory5() override { print_destroyed(this); }
};

class TestFactory6 {
protected:
    int value;
    bool alias = false;
public:
    TestFactory6(int i) : value{i} { print_created(this, i); }
    TestFactory6(TestFactory6 &&f) { print_move_created(this); value = f.value; alias = f.alias; }
    TestFactory6(const TestFactory6 &f) { print_copy_created(this); value = f.value; alias = f.alias; }
    virtual ~TestFactory6() { print_destroyed(this); }
    virtual int get() { return value; }
    bool has_alias() { return alias; }
};
class PyTF6 : public TestFactory6 {
public:
    // Special constructor that allows the factory to construct a PyTF6 from a TestFactory6 only
    // when an alias is needed:
    PyTF6(TestFactory6 &&base) : TestFactory6(std::move(base)) { alias = true; print_created(this, "move", value); }
    PyTF6(int i) : TestFactory6(i) { alias = true; print_created(this, i); }
    PyTF6(PyTF6 &&f) : TestFactory6(std::move(f)) { print_move_created(this); }
    PyTF6(const PyTF6 &f) : TestFactory6(f) { print_copy_created(this); }
    PyTF6(std::string s) : TestFactory6((int) s.size()) { alias = true; print_created(this, s); }
    ~PyTF6() override { print_destroyed(this); }
    int get() override { PYBIND11_OVERRIDE(int, TestFactory6, get, /*no args*/); }
};

class TestFactory7 {
protected:
    int value;
    bool alias = false;
public:
    TestFactory7(int i) : value{i} { print_created(this, i); }
    TestFactory7(TestFactory7 &&f) { print_move_created(this); value = f.value; alias = f.alias; }
    TestFactory7(const TestFactory7 &f) { print_copy_created(this); value = f.value; alias = f.alias; }
    virtual ~TestFactory7() { print_destroyed(this); }
    virtual int get() { return value; }
    bool has_alias() { return alias; }
};
class PyTF7 : public TestFactory7 {
public:
    PyTF7(int i) : TestFactory7(i) { alias = true; print_created(this, i); }
    PyTF7(PyTF7 &&f) : TestFactory7(std::move(f)) { print_move_created(this); }
    PyTF7(const PyTF7 &f) : TestFactory7(f) { print_copy_created(this); }
    ~PyTF7() override { print_destroyed(this); }
    int get() override { PYBIND11_OVERRIDE(int, TestFactory7, get, /*no args*/); }
};


class TestFactoryHelper {
public:
    // Non-movable, non-copyable type:
    // Return via pointer:
    static TestFactory1 *construct1() { return new TestFactory1(); }
    // Holder:
    static std::unique_ptr<TestFactory1> construct1(int a) { return std::unique_ptr<TestFactory1>(new TestFactory1(a)); }
    // pointer again
    static TestFactory1 *construct1_string(std::string a) { return new TestFactory1(a); }

    // Moveable type:
    // pointer:
    static TestFactory2 *construct2() { return new TestFactory2(); }
    // holder:
    static std::unique_ptr<TestFactory2> construct2(int a) { return std::unique_ptr<TestFactory2>(new TestFactory2(a)); }
    // by value moving:
    static TestFactory2 construct2(std::string a) { return TestFactory2(a); }

    // shared_ptr holder type:
    // pointer:
    static TestFactory3 *construct3() { return new TestFactory3(); }
    // holder:
    static std::shared_ptr<TestFactory3> construct3(int a) { return std::shared_ptr<TestFactory3>(new TestFactory3(a)); }
};

TEST_SUBMODULE(factory_constructors, m) {

    // Define various trivial types to allow simpler overload resolution:
    py::module_ m_tag = m.def_submodule("tag");
#define MAKE_TAG_TYPE(Name) \
    struct Name##_tag {}; \
    py::class_<Name##_tag>(m_tag, #Name "_tag").def(py::init<>()); \
    m_tag.attr(#Name) = py::cast(Name##_tag{})
    MAKE_TAG_TYPE(pointer);
    MAKE_TAG_TYPE(unique_ptr);
    MAKE_TAG_TYPE(move);
    MAKE_TAG_TYPE(shared_ptr);
    MAKE_TAG_TYPE(derived);
    MAKE_TAG_TYPE(TF4);
    MAKE_TAG_TYPE(TF5);
    MAKE_TAG_TYPE(null_ptr);
    MAKE_TAG_TYPE(null_unique_ptr);
    MAKE_TAG_TYPE(null_shared_ptr);
    MAKE_TAG_TYPE(base);
    MAKE_TAG_TYPE(invalid_base);
    MAKE_TAG_TYPE(alias);
    MAKE_TAG_TYPE(unaliasable);
    MAKE_TAG_TYPE(mixed);

    // test_init_factory_basic, test_bad_type
    py::class_<TestFactory1>(m, "TestFactory1")
        .def(py::init([](unique_ptr_tag, int v) { return TestFactoryHelper::construct1(v); }))
        .def(py::init(&TestFactoryHelper::construct1_string)) // raw function pointer
        .def(py::init([](pointer_tag) { return TestFactoryHelper::construct1(); }))
        .def(py::init([](py::handle, int v, py::handle) { return TestFactoryHelper::construct1(v); }))
        .def_readwrite("value", &TestFactory1::value)
        ;
    py::class_<TestFactory2>(m, "TestFactory2")
        .def(py::init([](pointer_tag, int v) { return TestFactoryHelper::construct2(v); }))
        .def(py::init([](unique_ptr_tag, std::string v) { return TestFactoryHelper::construct2(v); }))
        .def(py::init([](move_tag) { return TestFactoryHelper::construct2(); }))
        .def_readwrite("value", &TestFactory2::value)
        ;

    // Stateful & reused:
    int c = 1;
    auto c4a = [c](pointer_tag, TF4_tag, int a) { (void) c; return new TestFactory4(a);};

    // test_init_factory_basic, test_init_factory_casting
    py::class_<TestFactory3, std::shared_ptr<TestFactory3>>(m, "TestFactory3")
        .def(py::init([](pointer_tag, int v) { return TestFactoryHelper::construct3(v); }))
        .def(py::init([](shared_ptr_tag) { return TestFactoryHelper::construct3(); }))
        .def("__init__", [](TestFactory3 &self, std::string v) { new (&self) TestFactory3(v); }) // placement-new ctor

        // factories returning a derived type:
        .def(py::init(c4a)) // derived ptr
        .def(py::init([](pointer_tag, TF5_tag, int a) { return new TestFactory5(a); }))
        // derived shared ptr:
        .def(py::init([](shared_ptr_tag, TF4_tag, int a) { return std::make_shared<TestFactory4>(a); }))
        .def(py::init([](shared_ptr_tag, TF5_tag, int a) { return std::make_shared<TestFactory5>(a); }))

        // Returns nullptr:
        .def(py::init([](null_ptr_tag) { return (TestFactory3 *) nullptr; }))
        .def(py::init([](null_unique_ptr_tag) { return std::unique_ptr<TestFactory3>(); }))
        .def(py::init([](null_shared_ptr_tag) { return std::shared_ptr<TestFactory3>(); }))

        .def_readwrite("value", &TestFactory3::value)
        ;

    // test_init_factory_casting
    py::class_<TestFactory4, TestFactory3, std::shared_ptr<TestFactory4>>(m, "TestFactory4")
        .def(py::init(c4a)) // pointer
        ;

    // Doesn't need to be registered, but registering makes getting ConstructorStats easier:
    py::class_<TestFactory5, TestFactory3, std::shared_ptr<TestFactory5>>(m, "TestFactory5");

    // test_init_factory_alias
    // Alias testing
    py::class_<TestFactory6, PyTF6>(m, "TestFactory6")
        .def(py::init([](base_tag, int i) { return TestFactory6(i); }))
        .def(py::init([](alias_tag, int i) { return PyTF6(i); }))
        .def(py::init([](alias_tag, std::string s) { return PyTF6(s); }))
        .def(py::init([](alias_tag, pointer_tag, int i) { return new PyTF6(i); }))
        .def(py::init([](base_tag, pointer_tag, int i) { return new TestFactory6(i); }))
        .def(py::init([](base_tag, alias_tag, pointer_tag, int i) { return (TestFactory6 *) new PyTF6(i); }))

        .def("get", &TestFactory6::get)
        .def("has_alias", &TestFactory6::has_alias)

        .def_static("get_cstats", &ConstructorStats::get<TestFactory6>, py::return_value_policy::reference)
        .def_static("get_alias_cstats", &ConstructorStats::get<PyTF6>, py::return_value_policy::reference)
        ;

    // test_init_factory_dual
    // Separate alias constructor testing
    py::class_<TestFactory7, PyTF7, std::shared_ptr<TestFactory7>>(m, "TestFactory7")
        .def(py::init(
            [](int i) { return TestFactory7(i); },
            [](int i) { return PyTF7(i); }))
        .def(py::init(
            [](pointer_tag, int i) { return new TestFactory7(i); },
            [](pointer_tag, int i) { return new PyTF7(i); }))
        .def(py::init(
            [](mixed_tag, int i) { return new TestFactory7(i); },
            [](mixed_tag, int i) { return PyTF7(i); }))
        .def(py::init(
            [](mixed_tag, std::string s) { return TestFactory7((int) s.size()); },
            [](mixed_tag, std::string s) { return new PyTF7((int) s.size()); }))
        .def(py::init(
            [](base_tag, pointer_tag, int i) { return new TestFactory7(i); },
            [](base_tag, pointer_tag, int i) { return (TestFactory7 *) new PyTF7(i); }))
        .def(py::init(
            [](alias_tag, pointer_tag, int i) { return new PyTF7(i); },
            [](alias_tag, pointer_tag, int i) { return new PyTF7(10*i); }))
        .def(py::init(
            [](shared_ptr_tag, base_tag, int i) { return std::make_shared<TestFactory7>(i); },
            [](shared_ptr_tag, base_tag, int i) { auto *p = new PyTF7(i); return std::shared_ptr<TestFactory7>(p); }))
        .def(py::init(
            [](shared_ptr_tag, invalid_base_tag, int i) { return std::make_shared<TestFactory7>(i); },
            [](shared_ptr_tag, invalid_base_tag, int i) { return std::make_shared<TestFactory7>(i); })) // <-- invalid alias factory

        .def("get", &TestFactory7::get)
        .def("has_alias", &TestFactory7::has_alias)

        .def_static("get_cstats", &ConstructorStats::get<TestFactory7>, py::return_value_policy::reference)
        .def_static("get_alias_cstats", &ConstructorStats::get<PyTF7>, py::return_value_policy::reference)
        ;

    // test_placement_new_alternative
    // Class with a custom new operator but *without* a placement new operator (issue #948)
    class NoPlacementNew {
    public:
        NoPlacementNew(int i) : i(i) { }
        static void *operator new(std::size_t s) {
            auto *p = ::operator new(s);
            py::print("operator new called, returning", reinterpret_cast<uintptr_t>(p));
            return p;
        }
        static void operator delete(void *p) {
            py::print("operator delete called on", reinterpret_cast<uintptr_t>(p));
            ::operator delete(p);
        }
        int i;
    };
    // As of 2.2, `py::init<args>` no longer requires placement new
    py::class_<NoPlacementNew>(m, "NoPlacementNew")
        .def(py::init<int>())
        .def(py::init([]() { return new NoPlacementNew(100); }))
        .def_readwrite("i", &NoPlacementNew::i)
        ;


    // test_reallocations
    // Class that has verbose operator_new/operator_delete calls
    struct NoisyAlloc {
        NoisyAlloc(const NoisyAlloc &) = default;
        NoisyAlloc(int i) { py::print(py::str("NoisyAlloc(int {})").format(i)); }
        NoisyAlloc(double d) { py::print(py::str("NoisyAlloc(double {})").format(d)); }
        ~NoisyAlloc() { py::print("~NoisyAlloc()"); }

        static void *operator new(size_t s) { py::print("noisy new"); return ::operator new(s); }
        static void *operator new(size_t, void *p) { py::print("noisy placement new"); return p; }
        static void operator delete(void *p, size_t) { py::print("noisy delete"); ::operator delete(p); }
        static void operator delete(void *, void *) { py::print("noisy placement delete"); }
#if defined(_MSC_VER) && _MSC_VER < 1910
        // MSVC 2015 bug: the above "noisy delete" isn't invoked (fixed in MSVC 2017)
        static void operator delete(void *p) { py::print("noisy delete"); ::operator delete(p); }
#endif
    };
    py::class_<NoisyAlloc>(m, "NoisyAlloc")
        // Since these overloads have the same number of arguments, the dispatcher will try each of
        // them until the arguments convert.  Thus we can get a pre-allocation here when passing a
        // single non-integer:
        .def("__init__", [](NoisyAlloc *a, int i) { new (a) NoisyAlloc(i); }) // Regular constructor, runs first, requires preallocation
        .def(py::init([](double d) { return new NoisyAlloc(d); }))

        // The two-argument version: first the factory pointer overload.
        .def(py::init([](int i, int) { return new NoisyAlloc(i); }))
        // Return-by-value:
        .def(py::init([](double d, int) { return NoisyAlloc(d); }))
        // Old-style placement new init; requires preallocation
        .def("__init__", [](NoisyAlloc &a, double d, double) { new (&a) NoisyAlloc(d); })
        // Requires deallocation of previous overload preallocated value:
        .def(py::init([](int i, double) { return new NoisyAlloc(i); }))
        // Regular again: requires yet another preallocation
        .def("__init__", [](NoisyAlloc &a, int i, std::string) { new (&a) NoisyAlloc(i); })
        ;




    // static_assert testing (the following def's should all fail with appropriate compilation errors):
#if 0
    struct BadF1Base {};
    struct BadF1 : BadF1Base {};
    struct PyBadF1 : BadF1 {};
    py::class_<BadF1, PyBadF1, std::shared_ptr<BadF1>> bf1(m, "BadF1");
    // wrapped factory function must return a compatible pointer, holder, or value
    bf1.def(py::init([]() { return 3; }));
    // incompatible factory function pointer return type
    bf1.def(py::init([]() { static int three = 3; return &three; }));
    // incompatible factory function std::shared_ptr<T> return type: cannot convert shared_ptr<T> to holder
    // (non-polymorphic base)
    bf1.def(py::init([]() { return std::shared_ptr<BadF1Base>(new BadF1()); }));
#endif
}