selfboot/test_backtrace.cpp

## test_backtrace.cpp
/**
 * traceback for cpp
 *
 *  Created on: 2018-01-27
 *      Author: owent
 *
 *  Released under the MIT license
 *
 *  @note Required flag -rdynamic or addr2line to get the function name when using gcc/clang in unix like system
 *  @note Using addr2line -Cfpe <exe_path> [func_addr...] for more detail when using gcc/clang
 *  @note Required flag /DEBUG /Zi to generate .pdb file when using MSVC
 */

#include <cstdlib>
#include <cstdio>
#include <string>

#ifndef BACKTRACE_MAX_FRAME_NUMBER
#define BACKTRACE_MAX_FRAME_NUMBER 100
#endif

#ifndef USING_WIN_DBG_ENG_COM
#define USING_WIN_DBG_ENG_COM 1
#endif
#ifndef USING_WIN_DBG_HELP
#define USING_WIN_DBG_HELP 1
#endif
#ifndef USING_GNU_UNWIND
#define USING_GNU_UNWIND 1
#endif
#ifndef USING_GNU_EXECINFO
#define USING_GNU_EXECINFO 1
#endif

#ifdef __GLIBCXX__
#include <cxxabi.h>
#define USING_LIBSTDCXX_ABI 1
#elif defined(_LIBCPP_ABI_VERSION)
#include <cxxabi.h>
#define USING_LIBCXX_ABI 1
#endif

#if defined(__cplusplus) && __cplusplus >= 201103L
#define USING_CXX11_NOEXCEPT noexcept
#else
#define USING_CXX11_NOEXCEPT
#endif

#ifdef USING_LIBUNWIND

#include <libunwind.h>

void print_trace() {
    unw_context_t unw_ctx;
    unw_cursor_t unw_cur;
    unw_proc_info_t unw_proc;
    unw_getcontext(&unw_ctx);
    unw_init_local(&unw_cur, &unw_ctx);

    char func_name_cache[256];
    unw_word_t unw_offset;
    int frame_id = 0;
#if defined(USING_LIBSTDCXX_ABI) || defined(USING_LIBCXX_ABI)
    int cxx_abi_status;
    char* realfunc_name;
#endif
    do {
        unw_get_proc_name(&unw_cur, func_name_cache, sizeof(func_name_cache), &unw_offset);
        unw_get_proc_info(&unw_cur, &unw_proc);
        const char* func_name = func_name_cache;
#if defined(USING_LIBSTDCXX_ABI) || defined(USING_LIBCXX_ABI)
        realfunc_name = abi::__cxa_demangle(func_name_cache, 0, 0, &cxx_abi_status);
        if (NULL != realfunc_name) {
            func_name = realfunc_name;
        }
#endif
        printf("Frame #%02d: (%s+0x%lx) [0x%lx]\n", frame_id, func_name, unw_offset, unw_proc.start_ip);

#if defined(USING_LIBSTDCXX_ABI) || defined(USING_LIBCXX_ABI)
        if (NULL != realfunc_name) {
            free(realfunc_name);
            realfunc_name = NULL;
        }
#endif

        int next_res = unw_step(&unw_cur);

        if (0 == next_res) {
            puts("All frames.");
            break;
        }

        if (UNW_EBADFRAME == next_res) {
            puts("Stop with UNW_EBADFRAME");
            break;
        }

        if (UNW_ESTOPUNWIND == next_res) {
            puts("Stop with UNW_ESTOPUNWIND");
            break;
        }

        if (UNW_EINVALIDIP == next_res) {
            puts("Stop with UNW_EINVALIDIP");
            break;
        }

        if (UNW_ENOINFO == next_res) {
            puts("Stop with UNW_ENOINFO");
            break;
        }
        ++ frame_id;
    } while(true);
}

#else

#if defined(_WIN32) && (!defined(__GNUC__) || (!defined(USING_GNU_UNWIND) || !USING_GNU_UNWIND))

#include <Windows.h>

#if defined(USING_WIN_DBG_HELP) && USING_WIN_DBG_HELP
#include <DbgHelp.h>
#endif

#if defined(USING_WIN_DBG_ENG_COM) && USING_WIN_DBG_ENG_COM
#include <DbgEng.h>
#endif

#ifdef _MSC_VER
    #if defined(USING_WIN_DBG_ENG_COM) && USING_WIN_DBG_ENG_COM
        #pragma comment(lib, "ole32.lib")
        #pragma comment(lib, "dbgeng.lib")
    #endif
    #if defined(USING_WIN_DBG_HELP) && USING_WIN_DBG_HELP
        #pragma comment(lib, "dbghelp.lib")
    #endif
#endif

#if defined(USING_WIN_DBG_ENG_COM) && USING_WIN_DBG_ENG_COM
    #ifdef __CRT_UUID_DECL // for __MINGW32__
        __CRT_UUID_DECL(IDebugClient,0x27fe5639,0x8407,0x4f47,0x83,0x64,0xee,0x11,0x8f,0xb0,0x8a,0xc8)
        __CRT_UUID_DECL(IDebugControl,0x5182e668,0x105e,0x416e,0xad,0x92,0x24,0xef,0x80,0x04,0x24,0xba)
        __CRT_UUID_DECL(IDebugSymbols,0x8c31e98c,0x983a,0x48a5,0x90,0x16,0x6f,0xe5,0xd6,0x67,0xa9,0x50)
    #elif defined(DEFINE_GUID) && !defined(BOOST_MSVC)
        DEFINE_GUID(IID_IDebugClient,0x27fe5639,0x8407,0x4f47,0x83,0x64,0xee,0x11,0x8f,0xb0,0x8a,0xc8);
        DEFINE_GUID(IID_IDebugControl,0x5182e668,0x105e,0x416e,0xad,0x92,0x24,0xef,0x80,0x04,0x24,0xba);
        DEFINE_GUID(IID_IDebugSymbols,0x8c31e98c,0x983a,0x48a5,0x90,0x16,0x6f,0xe5,0xd6,0x67,0xa9,0x50);
    #endif

template <class T>
class print_trace_com_holder {
private:
    T* holder_;

private:
    print_trace_com_holder(const print_trace_com_holder&);
    print_trace_com_holder& operator=(const print_trace_com_holder&);

public:
    print_trace_com_holder() USING_CXX11_NOEXCEPT : holder_(NULL) {}
    ~print_trace_com_holder() USING_CXX11_NOEXCEPT {
        if (holder_) {
            holder_->Release();
        }
    }

    T* operator->() const USING_CXX11_NOEXCEPT {
        return holder_;
    }

    PVOID* to_pvoid_ptr()  USING_CXX11_NOEXCEPT {
        return reinterpret_cast<PVOID*>(&holder_);
    }

    bool is_inited() const USING_CXX11_NOEXCEPT {
        return !!holder_;
    }
};
#endif

void print_trace() USING_CXX11_NOEXCEPT {
    void         * stack[ BACKTRACE_MAX_FRAME_NUMBER ];
    unsigned short frames;

    frames = CaptureStackBackTrace( 0, BACKTRACE_MAX_FRAME_NUMBER, stack, NULL );

#if !defined(_MSC_VER)
    for(unsigned short i = 0; i < frames; i++ ) {
        printf( "Frame %02i: () [0x%p]\n", i, stack[ i ]);
    }

#else // MSVC required flag: /DEBUG /Zi
    #if defined(USING_WIN_DBG_HELP) && USING_WIN_DBG_HELP
    SYMBOL_INFO  * symbol;
    HANDLE         process;
    DWORD64        displacement = 0;
    process = GetCurrentProcess();

    // SymSetOptions(SYMOPT_UNDNAME | SYMOPT_DEFERRED_LOADS | SYMOPT_LOAD_LINES);
    SymInitialize( process, NULL, TRUE );

    symbol               = ( SYMBOL_INFO * )malloc(sizeof( SYMBOL_INFO ) + (MAX_SYM_NAME + 1) * sizeof(TCHAR));
    symbol->MaxNameLen   = MAX_SYM_NAME;
    symbol->SizeOfStruct = sizeof( SYMBOL_INFO );

    for(unsigned short i = 0; i < frames; i++ ) {
        if(SymFromAddr( process, reinterpret_cast<ULONG64>(stack[i]), &displacement, symbol )) {
            printf( "Frame %02i: (%s) [0x%p]\n", i, &symbol->Name[0], symbol->Address );
        } else {
            printf( "Frame %02i: () [0x%p]\n", i, stack[i]);
        }
    }

    free(symbol);
    SymCleanup(process);
    #endif

    // ================== Using IDebugClient ==================
    #if defined(USING_WIN_DBG_ENG_COM) && USING_WIN_DBG_ENG_COM
    print_trace_com_holder<IDebugClient> dbg_cli;
    print_trace_com_holder<IDebugControl> dbg_ctrl;
    print_trace_com_holder<IDebugSymbols> dbg_sym;
    if (S_OK != ::DebugCreate(__uuidof(IDebugClient), dbg_cli.to_pvoid_ptr())) {
        return;
    }
    const bool res0 = (S_OK == dbg_cli->QueryInterface(
        __uuidof(IDebugControl),
        dbg_ctrl.to_pvoid_ptr()
    ));
    if (!res0) {
        return;
    }

    const bool res1 = (S_OK == dbg_cli->AttachProcess(
        0,
        ::GetCurrentProcessId(),
        DEBUG_ATTACH_NONINVASIVE | DEBUG_ATTACH_NONINVASIVE_NO_SUSPEND
    ));
    if (!res1) {
        return;
    }

    if (S_OK != dbg_ctrl->WaitForEvent(DEBUG_WAIT_DEFAULT, INFINITE)) {
        return;
    }

    // No cheking: QueryInterface sets the output parameter to NULL in case of error.
    dbg_cli->QueryInterface(__uuidof(IDebugSymbols), dbg_sym.to_pvoid_ptr());

    for(unsigned short i = 0; i < frames; i++ ) {
        if (!dbg_sym.is_inited()) {
            break;
        }

        const ULONG64 offset = reinterpret_cast<ULONG64>(stack[i]);

        char name[256];
        name[0] = '\0';
        ULONG size = 0;
        bool res = (S_OK == dbg_sym->GetNameByOffset(
            offset,
            name,
            sizeof(name),
            &size,
            0
        ));

        std::string result;
        if (!res && size != 0) {
            result.resize(size);
            res = (S_OK == dbg_sym->GetNameByOffset(
                offset,
                &result[0],
                static_cast<ULONG>(result.size()),
                &size,
                0
            ));
        } else if (res) {
            result = name;
        }

        printf( "Frame %02i: (%s) [0x%p]\n", i, result.c_str(), stack[i]);
    }
    #endif
#endif
}

#else

#if defined(USING_GNU_EXECINFO) && USING_GNU_EXECINFO
#include <execinfo.h>
#endif

#if defined(USING_GNU_UNWIND) && USING_GNU_UNWIND
#include <unwind.h>

struct print_trace_unwind_state_t {
    size_t frames_to_skip;
    _Unwind_Word* current;
    _Unwind_Word* end;
};

static _Unwind_Reason_Code print_trace_unwind_callback(::_Unwind_Context* context, void* arg) {
    // Note: do not write `::_Unwind_GetIP` because it is a macro on some platforms.
    // Use `_Unwind_GetIP` instead!
    print_trace_unwind_state_t* const state = reinterpret_cast<print_trace_unwind_state_t*>(arg);
    if (state->frames_to_skip) {
        --state->frames_to_skip;
        return _Unwind_GetIP(context) ? ::_URC_NO_REASON : ::_URC_END_OF_STACK;
    }

    *state->current = _Unwind_GetIP(context);

    ++state->current;
    if (!*(state->current - 1) || state->current == state->end) {
        return ::_URC_END_OF_STACK;
    }

    return ::_URC_NO_REASON;
}

#endif

/* Obtain a backtrace and print it to stdout. */

struct print_trace_symbol_group_t {
    std::string module_name;
    std::string func_name;
    std::string func_offset;
    std::string func_address;
};

static const char* print_trace_skip_space(const char* name) {
    if (NULL == name) {
        return name;
    }

    while (*name && (' ' == *name || '\r' == *name || '\t' == *name || '\r' == *name)) {
        ++name;
    }

    return name;
}

inline bool print_trace_is_number_char(char c) {
    return c >= '0' && c <= '9';
}

inline bool print_trace_is_ident_char(char c) {
    return '_' == c || '$' == c || print_trace_is_number_char(c) || (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c & 0x80);// utf-8 or unicode
}

static const char* print_trace_get_ident_end(const char* name) {
    if (NULL == name) {
        return name;
    }

    while (*name && print_trace_is_ident_char(*name)) {
        ++ name;
    }

    return name;
}

static bool print_trace_pick_ident(const char* name, const char*& start, const char*& end, char& previous_c) {
    previous_c = 0;
    start = name;
    end = name;

    bool ret = false;
    if (NULL == name) {
        return false;
    }

    while(*name) {
        name = print_trace_skip_space(name);

        if (print_trace_is_ident_char(*name)) {
            start = name;
            end = print_trace_get_ident_end(name);
            ret = true;
            break;
        } else {
            previous_c = *name;
            ++name;
        }
    }

    return ret;
}

static void print_trace_pick_symbol_info (const char* name, print_trace_symbol_group_t& out) {
    out.module_name.clear();
    out.func_name.clear();
    out.func_offset.clear();
    out.func_address.clear();

    if (NULL == name || 0 == *name) {
        return;
    }

    name = print_trace_skip_space(name);
    while (name) {
        const char* start;
        char previous_c;

        if (print_trace_pick_ident(name, start, name, previous_c)) {
            if (print_trace_is_number_char(*start)) {
                if ('+' == previous_c) {
                    out.func_offset = "+";
                    out.func_offset.insert(out.func_offset.end(), start, name);
                } else {
                    out.func_address.assign(start, name);
                }
            } else {
                if (out.module_name.empty()) {
                    out.module_name.assign(start, name);
                } else {
                    out.func_name.assign(start, name);
                }
            }
        } else {
            break;
        }

        name = print_trace_skip_space(name);
    }
}

void print_trace () {
#if defined(USING_GNU_EXECINFO) && USING_GNU_EXECINFO
    {
        void *array[BACKTRACE_MAX_FRAME_NUMBER];
        size_t size;
        char **func_name_cache;

        size = backtrace (array, BACKTRACE_MAX_FRAME_NUMBER);
        func_name_cache = backtrace_symbols (array, size);

        for (size_t i = 0; i < size; i++) {
            print_trace_symbol_group_t symbol;
            print_trace_pick_symbol_info(func_name_cache[i], symbol);

    #if defined(USING_LIBSTDCXX_ABI) || defined(USING_LIBCXX_ABI)
            if (!symbol.func_name.empty()) {
                int cxx_abi_status;
                char* realfunc_name = abi::__cxa_demangle(symbol.func_name.c_str(), 0, 0, &cxx_abi_status);
                if (NULL != realfunc_name) {
                    symbol.func_name = realfunc_name;
                }

                if (NULL != realfunc_name) {
                    free(realfunc_name);
                }
            }
    #endif

            printf("Frame #%02d: (%s%s) [%s]\n", static_cast<int>(i), symbol.func_name.c_str(), symbol.func_offset.c_str(), symbol.func_address.c_str());
        }

        free (func_name_cache);
    }
#endif

#if defined(USING_GNU_UNWIND) && USING_GNU_UNWIND
    {
        _Unwind_Word stacks[BACKTRACE_MAX_FRAME_NUMBER];
        print_trace_unwind_state_t state;
        state.frames_to_skip = 0;
        state.current = stacks;
        state.end = stacks + BACKTRACE_MAX_FRAME_NUMBER;

        ::_Unwind_Backtrace(&print_trace_unwind_callback, &state);
        size_t frames_count = state.current - &stacks[0];
        for (size_t i = 0; i < frames_count; ++ i) {
            printf("Frame #%02d: () [0x%lx]\n", static_cast<int>(i), stacks[i]);
        }
    }
#endif
}
#endif

#endif

void func1(int times) {
    if (times > 0) {
        func1(times - 1);
        return;
    }

    print_trace();
}

class functor2 {
public:
    void func2(int times) {
        if (times & 0x01) {
            func2(times - 1);
        } else {
            func1(times - 1);
        }
    }
};

class functor3 {
public:
    static void func3(int times) {
        if (times & 0x01) {
            func3(times - 1);
        } else {
            functor2 f;
            f.func2(times - 1);
        }
    }
};

struct functor4 {
    void operator()(int times) {
        if (times & 0x01) {
            (*this)(times - 1);
        } else {
            functor3::func3(times - 1);
        }
    }
};

static void func5(int times) {
    if (times & 0x01) {
        func5(times - 1);
    } else {
        functor4 f;
        f(times - 1);
    }
}

void func6(int times) {
    if (times & 0x01) {
        func6(times - 1);
    } else {
        func5(times - 1);
    }
}

int main (int argc, char* argv[]) {
    int times = 15;
    if (argc > 1) {
        times = atoi(argv[1]);
    }
    func6(times);
    return 0;
}


## test_backtrace.md

      
    Raw
  

              test_backtrace.md
            
          
    Linux下使用libunwind

g++ -Wall test_backtrace.cpp -O0 -g -ggdb -rdynamic -o test_backtrace.exe -DUSING_LIBUNWIND -lunwind -lunwind-x86_64
clang++ -Wall test_backtrace.cpp -O0 -g -ggdb -rdynamic -o test_backtrace.exe -DUSING_LIBUNWIND -lunwind -lunwind-x86_64
命令和输出:
./test_backtrace.exe

Frame #00: (print_trace()+0x17) [0x400c30]
Frame #01: (func1(int)+0x2c) [0x400e80]
Frame #02: (func1(int)+0x22) [0x400e80]
Frame #03: (func1(int)+0x22) [0x400e80]
Frame #04: (func1(int)+0x22) [0x400e80]
Frame #05: (func1(int)+0x22) [0x400e80]
Frame #06: (func1(int)+0x22) [0x400e80]
Frame #07: (functor2::func2(int)+0x49) [0x401040]
Frame #08: (functor2::func2(int)+0x37) [0x401040]
Frame #09: (functor3::func3(int)+0x3d) [0x400ff0]
Frame #10: (functor3::func3(int)+0x27) [0x400ff0]
Frame #11: (functor4::operator()(int)+0x49) [0x400fa0]
Frame #12: (functor4::operator()(int)+0x37) [0x400fa0]
Frame #13: (func5(int)+0x3d) [0x400f00]
Frame #14: (func5(int)+0x27) [0x400f00]
Frame #15: (func6(int)+0x39) [0x400ec0]
Frame #16: (func6(int)+0x27) [0x400ec0]
Frame #17: (main+0x3f) [0x400f50]
Frame #18: (__libc_start_main+0xf0) [0x7f2d3cf50740]
Frame #19: (_start+0x29) [0x400b30]
Frame #20: (+0x29) [0x0]
All frames.

Linux下使用backtrace

g++ -Wall test_backtrace.cpp -O0 -g -ggdb -rdynamic -o test_backtrace.exe
clang++ -Wall test_backtrace.cpp -O0 -g -ggdb -rdynamic -o test_backtrace.exe
命令和输出:
./test_backtrace.exe

Frame #00: (print_trace()+0x1c) [0x4013ec]
Frame #01: (func1(int)+0x2c) [0x4019dc]
Frame #02: (func1(int)+0x22) [0x4019d2]
Frame #03: (func1(int)+0x22) [0x4019d2]
Frame #04: (func1(int)+0x22) [0x4019d2]
Frame #05: (func1(int)+0x22) [0x4019d2]
Frame #06: (func1(int)+0x22) [0x4019d2]
Frame #07: (functor2::func2(int)+0x49) [0x402189]
Frame #08: (functor2::func2(int)+0x37) [0x402177]
Frame #09: (functor3::func3(int)+0x3d) [0x40212d]
Frame #10: (functor3::func3(int)+0x27) [0x402117]
Frame #11: (functor4::operator()(int)+0x49) [0x4020e9]
Frame #12: (functor4::operator()(int)+0x37) [0x4020d7]
Frame #13: () [0x401a6d]
Frame #14: () [0x401a57]
Frame #15: (func6(int)+0x39) [0x401a29]
Frame #16: (func6(int)+0x27) [0x401a17]
Frame #17: (main+0x3f) [0x401abf]
Frame #18: (__libc_start_main+0xf0) [0x7f7ffc390830]
Frame #19: (_start+0x29) [0x4012f9]

Linux下使用backtrace+addr2line

g++ -Wall test_backtrace.cpp -O0 -g -ggdb -o test_backtrace.exe
clang++ -Wall test_backtrace.cpp -O0 -g -ggdb -o test_backtrace.exe
命令和输出:
./test_backtrace.exe | eval 'while read -r line || [[ -n "$line" ]]; do ADDR=${line/*[}; ADDR=${ADDR%]*}; echo "${line}"; echo "    $(addr2line -Cfpe ./test_backtrace.exe $ADDR)"; done'

Frame #00: () [0x40167a]
    print_trace() at /mnt/d/workspace/test/test_backtrace.cpp:474
Frame #01: () [0x4019dc]
    func1(int) at /mnt/d/workspace/test/test_backtrace.cpp:493 (discriminator 1)
Frame #02: () [0x4019d2]
    func1(int) at /mnt/d/workspace/test/test_backtrace.cpp:489
Frame #03: () [0x4019d2]
    func1(int) at /mnt/d/workspace/test/test_backtrace.cpp:489
Frame #04: () [0x4019d2]
    func1(int) at /mnt/d/workspace/test/test_backtrace.cpp:489
Frame #05: () [0x4019d2]
    func1(int) at /mnt/d/workspace/test/test_backtrace.cpp:489
Frame #06: () [0x4019d2]
    func1(int) at /mnt/d/workspace/test/test_backtrace.cpp:489
Frame #07: () [0x402189]
    functor2::func2(int) at /mnt/d/workspace/test/test_backtrace.cpp:503
Frame #08: () [0x402177]
    functor2::func2(int) at /mnt/d/workspace/test/test_backtrace.cpp:500
Frame #09: () [0x40212d]
    functor3::func3(int) at /mnt/d/workspace/test/test_backtrace.cpp:515
Frame #10: () [0x402117]
    functor3::func3(int) at /mnt/d/workspace/test/test_backtrace.cpp:511
Frame #11: () [0x4020e9]
    functor4::operator()(int) at /mnt/d/workspace/test/test_backtrace.cpp:525
Frame #12: () [0x4020d7]
    functor4::operator()(int) at /mnt/d/workspace/test/test_backtrace.cpp:522
Frame #13: () [0x401a6d]
    func5(int) at /mnt/d/workspace/test/test_backtrace.cpp:535
Frame #14: () [0x401a57]
    func5(int) at /mnt/d/workspace/test/test_backtrace.cpp:531
Frame #15: () [0x401a29]
    func6(int) at /mnt/d/workspace/test/test_backtrace.cpp:543
Frame #16: () [0x401a17]
    func6(int) at /mnt/d/workspace/test/test_backtrace.cpp:540
Frame #17: () [0x401abf]
    main at /mnt/d/workspace/test/test_backtrace.cpp:550
Frame #18: () [0x7f3c44f90830]
    ?? ??:0
Frame #19: () [0x4012f9]
    _start at ??:?
Frame #20: () [0x0]
    ?? ??:0

Windows+MSVC使用dbghelp

cl /nologo /W4 /DEBUG /Zi test_backtrace.cpp
命令和输出:
test_backtrace.exe

Frame 00: (print_trace) [0x00007FF6C75768F0]
Frame 01: (func1) [0x00007FF6C7576EE0]
Frame 02: (func1) [0x00007FF6C7576EE0]
Frame 03: (func1) [0x00007FF6C7576EE0]
Frame 04: (func1) [0x00007FF6C7576EE0]
Frame 05: (func1) [0x00007FF6C7576EE0]
Frame 06: (func1) [0x00007FF6C7576EE0]
Frame 07: (functor2::func2) [0x00007FF6C7578850]
Frame 08: (functor2::func2) [0x00007FF6C7578850]
Frame 09: (functor3::func3) [0x00007FF6C75788A0]
Frame 10: (functor3::func3) [0x00007FF6C75788A0]
Frame 11: (functor4::operator()) [0x00007FF6C7577D20]
Frame 12: (functor4::operator()) [0x00007FF6C7577D20]
Frame 13: (func5) [0x00007FF6C7576F10]
Frame 14: (func5) [0x00007FF6C7576F10]
Frame 15: (func6) [0x00007FF6C7576F50]
Frame 16: (func6) [0x00007FF6C7576F50]
Frame 17: (main) [0x00007FF6C7576F90]
Frame 18: (__scrt_common_main_seh) [0x00007FF6C757A078]
Frame 19: (BaseThreadInitThunk) [0x00007FFCAA081FD0]
Frame 20: (RtlUserThreadStart) [0x00007FFCAC64EF90]

Windows+MSVC使用dbgeng组件

cl /nologo /W4 /DEBUG /Zi test_backtrace.cpp
命令和输出:
test_backtrace.exe

Frame 00: (test_backtrace!print_trace) [0x00007FF6C7576921]
Frame 01: (test_backtrace!func1) [0x00007FF6C7576F03]
Frame 02: (test_backtrace!func1) [0x00007FF6C7576EFC]
Frame 03: (test_backtrace!func1) [0x00007FF6C7576EFC]
Frame 04: (test_backtrace!func1) [0x00007FF6C7576EFC]
Frame 05: (test_backtrace!func1) [0x00007FF6C7576EFC]
Frame 06: (test_backtrace!func1) [0x00007FF6C7576EFC]
Frame 07: (test_backtrace!functor2::func2) [0x00007FF6C7578889]
Frame 08: (test_backtrace!functor2::func2) [0x00007FF6C757887A]
Frame 09: (test_backtrace!functor3::func3) [0x00007FF6C75788D4]
Frame 10: (test_backtrace!functor3::func3) [0x00007FF6C75788C0]
Frame 11: (test_backtrace!functor4::operator()) [0x00007FF6C7577D59]
Frame 12: (test_backtrace!functor4::operator()) [0x00007FF6C7577D4A]
Frame 13: (test_backtrace!func5) [0x00007FF6C7576F44]
Frame 14: (test_backtrace!func5) [0x00007FF6C7576F30]
Frame 15: (test_backtrace!func6) [0x00007FF6C7576F7F]
Frame 16: (test_backtrace!func6) [0x00007FF6C7576F70]
Frame 17: (test_backtrace!main) [0x00007FF6C7576FD0]
Frame 18: (test_backtrace!__scrt_common_main_seh) [0x00007FF6C757A188]
Frame 19: (KERNEL32!BaseThreadInitThunk) [0x00007FFCAA081FE4]
Frame 20: (ntdll!RtlUserThreadStart) [0x00007FFCAC64EFB1]

Windows+Mingw64+addr2line

g++ test_backtrace.cpp -O0 -g -ggdb -o test_backtrace.exe -ldbghelp -ldbgeng -Wall -DUSING_GNU_UNWIND=0
clang++ test_backtrace.cpp -O0 -g -ggdb -o test_backtrace.exe -ldbghelp -ldbgeng -Wall -DUSING_GNU_UNWIND=0
命令和输出:
./test_backtrace.exe | eval 'while read -r line || [[ -n "$line" ]]; do ADDR=${line/*[}; ADDR=${ADDR%]*}; echo "${line}"; echo "    $(addr2line -Cfpe ./test_backtrace.exe $ADDR)"; done'

Frame 00: () [0x00000000004015b4]
    print_trace() 于 D:\workspace\test/test_backtrace.cpp:176
Frame 01: () [0x000000000040163b]
    func1(int) 于 D:\workspace\test/test_backtrace.cpp:353
Frame 02: () [0x0000000000401631]
    func1(int) 于 D:\workspace\test/test_backtrace.cpp:349
Frame 03: () [0x0000000000401631]
    func1(int) 于 D:\workspace\test/test_backtrace.cpp:349
Frame 04: () [0x0000000000401631]
    func1(int) 于 D:\workspace\test/test_backtrace.cpp:349
Frame 05: () [0x0000000000401631]
    func1(int) 于 D:\workspace\test/test_backtrace.cpp:349
Frame 06: () [0x0000000000401631]
    func1(int) 于 D:\workspace\test/test_backtrace.cpp:349
Frame 07: () [0x000000000040189d]
    functor2::func2(int) 于 D:\workspace\test/test_backtrace.cpp:363
Frame 08: () [0x000000000040188a]
    functor2::func2(int) 于 D:\workspace\test/test_backtrace.cpp:360
Frame 09: () [0x000000000040183e]
    functor3::func3(int) 于 D:\workspace\test/test_backtrace.cpp:375
Frame 10: () [0x0000000000401826]
    functor3::func3(int) 于 D:\workspace\test/test_backtrace.cpp:371
Frame 11: () [0x00000000004017ed]
    functor4::operator()(int) 于 D:\workspace\test/test_backtrace.cpp:385
Frame 12: () [0x00000000004017da]
    functor4::operator()(int) 于 D:\workspace\test/test_backtrace.cpp:382
Frame 13: () [0x00000000004016ce]
    func5(int) 于 D:\workspace\test/test_backtrace.cpp:395
Frame 14: () [0x00000000004016b6]
    func5(int) 于 D:\workspace\test/test_backtrace.cpp:391
Frame 15: () [0x0000000000401689]
    func6(int) 于 D:\workspace\test/test_backtrace.cpp:403
Frame 16: () [0x0000000000401676]
    func6(int) 于 D:\workspace\test/test_backtrace.cpp:400
Frame 17: () [0x0000000000401734]
    main 于 D:\workspace\test/test_backtrace.cpp:410
Frame 18: () [0x00000000004013f7]
    __tmainCRTStartup 于 C:/repo/mingw-w64-crt-git/src/mingw-w64/mingw-w64-crt/crt/crtexe.c:343
Frame 19: () [0x000000000040152b]
    mainCRTStartup 于 C:/repo/mingw-w64-crt-git/src/mingw-w64/mingw-w64-crt/crt/crtexe.c:221
Frame 20: () [0x00007ffcaa081fe4]
    ?? ??:0
Frame 21: () [0x00007ffcac64efb1]
    ?? ??:0

Linux+gcc/clang+unwind+addr2line

g++ test_backtrace.cpp -O0 -g -ggdb -o test_backtrace.exe -Wall -DUSING_GNU_EXECINFO=0
clang++ test_backtrace.cpp -O0 -g -ggdb -o test_backtrace.exe -Wall -DUSING_GNU_EXECINFO=0
命令和输出:
./test_backtrace.exe | eval 'while read -r line || [[ -n "$line" ]]; do ADDR=${line/*[}; ADDR=${ADDR%]*}; echo "${line}"; echo "    $(addr2line -Cfpe ./test_backtrace.exe $ADDR)"; done'

Frame 00: () [0x00000000004015b4]
    print_trace() 于 D:\workspace\test/test_backtrace.cpp:176
Frame 01: () [0x000000000040163b]
    func1(int) 于 D:\workspace\test/test_backtrace.cpp:353
Frame 02: () [0x0000000000401631]
    func1(int) 于 D:\workspace\test/test_backtrace.cpp:349
Frame 03: () [0x0000000000401631]
    func1(int) 于 D:\workspace\test/test_backtrace.cpp:349
Frame 04: () [0x0000000000401631]
    func1(int) 于 D:\workspace\test/test_backtrace.cpp:349
Frame 05: () [0x0000000000401631]
    func1(int) 于 D:\workspace\test/test_backtrace.cpp:349
Frame 06: () [0x0000000000401631]
    func1(int) 于 D:\workspace\test/test_backtrace.cpp:349
Frame 07: () [0x000000000040189d]
    functor2::func2(int) 于 D:\workspace\test/test_backtrace.cpp:363
Frame 08: () [0x000000000040188a]
    functor2::func2(int) 于 D:\workspace\test/test_backtrace.cpp:360
Frame 09: () [0x000000000040183e]
    functor3::func3(int) 于 D:\workspace\test/test_backtrace.cpp:375
Frame 10: () [0x0000000000401826]
    functor3::func3(int) 于 D:\workspace\test/test_backtrace.cpp:371
Frame 11: () [0x00000000004017ed]
    functor4::operator()(int) 于 D:\workspace\test/test_backtrace.cpp:385
Frame 12: () [0x00000000004017da]
    functor4::operator()(int) 于 D:\workspace\test/test_backtrace.cpp:382
Frame 13: () [0x00000000004016ce]
    func5(int) 于 D:\workspace\test/test_backtrace.cpp:395
Frame 14: () [0x00000000004016b6]
    func5(int) 于 D:\workspace\test/test_backtrace.cpp:391
Frame 15: () [0x0000000000401689]
    func6(int) 于 D:\workspace\test/test_backtrace.cpp:403
Frame 16: () [0x0000000000401676]
    func6(int) 于 D:\workspace\test/test_backtrace.cpp:400
Frame 17: () [0x0000000000401734]
    main 于 D:\workspace\test/test_backtrace.cpp:410
Frame 18: () [0x00000000004013f7]
    __tmainCRTStartup 于 C:/repo/mingw-w64-crt-git/src/mingw-w64/mingw-w64-crt/crt/crtexe.c:343
Frame 19: () [0x000000000040152b]
    mainCRTStartup 于 C:/repo/mingw-w64-crt-git/src/mingw-w64/mingw-w64-crt/crt/crtexe.c:221
Frame 20: () [0x00007ffcaa081fe4]
    ?? ??:0
Frame 21: () [0x00007ffcac64efb1]
    ?? ??:0
	/**
	* traceback for cpp
	*
	* Created on: 2018-01-27
	* Author: owent
	*
	* Released under the MIT license
	*
	* @note Required flag -rdynamic or addr2line to get the function name when using gcc/clang in unix like system
	* @note Using addr2line -Cfpe <exe_path> [func_addr...] for more detail when using gcc/clang
	* @note Required flag /DEBUG /Zi to generate .pdb file when using MSVC
	*/

	#include <cstdlib>
	#include <cstdio>
	#include <string>

	#ifndef BACKTRACE_MAX_FRAME_NUMBER
	#define BACKTRACE_MAX_FRAME_NUMBER 100
	#endif

	#ifndef USING_WIN_DBG_ENG_COM
	#define USING_WIN_DBG_ENG_COM 1
	#endif
	#ifndef USING_WIN_DBG_HELP
	#define USING_WIN_DBG_HELP 1
	#endif
	#ifndef USING_GNU_UNWIND
	#define USING_GNU_UNWIND 1
	#endif
	#ifndef USING_GNU_EXECINFO
	#define USING_GNU_EXECINFO 1
	#endif

	#ifdef __GLIBCXX__
	#include <cxxabi.h>
	#define USING_LIBSTDCXX_ABI 1
	#elif defined(_LIBCPP_ABI_VERSION)
	#include <cxxabi.h>
	#define USING_LIBCXX_ABI 1
	#endif

	#if defined(__cplusplus) && __cplusplus >= 201103L
	#define USING_CXX11_NOEXCEPT noexcept
	#else
	#define USING_CXX11_NOEXCEPT
	#endif

	#ifdef USING_LIBUNWIND

	#include <libunwind.h>

	void print_trace() {
	unw_context_t unw_ctx;
	unw_cursor_t unw_cur;
	unw_proc_info_t unw_proc;
	unw_getcontext(&unw_ctx);
	unw_init_local(&unw_cur, &unw_ctx);

	char func_name_cache[256];
	unw_word_t unw_offset;
	int frame_id = 0;
	#if defined(USING_LIBSTDCXX_ABI) \|\| defined(USING_LIBCXX_ABI)
	int cxx_abi_status;
	char* realfunc_name;
	#endif
	do {
	unw_get_proc_name(&unw_cur, func_name_cache, sizeof(func_name_cache), &unw_offset);
	unw_get_proc_info(&unw_cur, &unw_proc);
	const char* func_name = func_name_cache;
	#if defined(USING_LIBSTDCXX_ABI) \|\| defined(USING_LIBCXX_ABI)
	realfunc_name = abi::__cxa_demangle(func_name_cache, 0, 0, &cxx_abi_status);
	if (NULL != realfunc_name) {
	func_name = realfunc_name;
	}
	#endif
	printf("Frame #%02d: (%s+0x%lx) [0x%lx]\n", frame_id, func_name, unw_offset, unw_proc.start_ip);

	#if defined(USING_LIBSTDCXX_ABI) \|\| defined(USING_LIBCXX_ABI)
	if (NULL != realfunc_name) {
	free(realfunc_name);
	realfunc_name = NULL;
	}
	#endif

	int next_res = unw_step(&unw_cur);

	if (0 == next_res) {
	puts("All frames.");
	break;
	}

	if (UNW_EBADFRAME == next_res) {
	puts("Stop with UNW_EBADFRAME");
	break;
	}

	if (UNW_ESTOPUNWIND == next_res) {
	puts("Stop with UNW_ESTOPUNWIND");
	break;
	}

	if (UNW_EINVALIDIP == next_res) {
	puts("Stop with UNW_EINVALIDIP");
	break;
	}

	if (UNW_ENOINFO == next_res) {
	puts("Stop with UNW_ENOINFO");
	break;
	}
	++ frame_id;
	} while(true);
	}

	#else

	#if defined(_WIN32) && (!defined(__GNUC__) \|\| (!defined(USING_GNU_UNWIND) \|\| !USING_GNU_UNWIND))

	#include <Windows.h>

	#if defined(USING_WIN_DBG_HELP) && USING_WIN_DBG_HELP
	#include <DbgHelp.h>
	#endif

	#if defined(USING_WIN_DBG_ENG_COM) && USING_WIN_DBG_ENG_COM
	#include <DbgEng.h>
	#endif

	#ifdef _MSC_VER
	#if defined(USING_WIN_DBG_ENG_COM) && USING_WIN_DBG_ENG_COM
	#pragma comment(lib, "ole32.lib")
	#pragma comment(lib, "dbgeng.lib")
	#endif
	#if defined(USING_WIN_DBG_HELP) && USING_WIN_DBG_HELP
	#pragma comment(lib, "dbghelp.lib")
	#endif
	#endif

	#if defined(USING_WIN_DBG_ENG_COM) && USING_WIN_DBG_ENG_COM
	#ifdef __CRT_UUID_DECL // for __MINGW32__
	__CRT_UUID_DECL(IDebugClient,0x27fe5639,0x8407,0x4f47,0x83,0x64,0xee,0x11,0x8f,0xb0,0x8a,0xc8)
	__CRT_UUID_DECL(IDebugControl,0x5182e668,0x105e,0x416e,0xad,0x92,0x24,0xef,0x80,0x04,0x24,0xba)
	__CRT_UUID_DECL(IDebugSymbols,0x8c31e98c,0x983a,0x48a5,0x90,0x16,0x6f,0xe5,0xd6,0x67,0xa9,0x50)
	#elif defined(DEFINE_GUID) && !defined(BOOST_MSVC)
	DEFINE_GUID(IID_IDebugClient,0x27fe5639,0x8407,0x4f47,0x83,0x64,0xee,0x11,0x8f,0xb0,0x8a,0xc8);
	DEFINE_GUID(IID_IDebugControl,0x5182e668,0x105e,0x416e,0xad,0x92,0x24,0xef,0x80,0x04,0x24,0xba);
	DEFINE_GUID(IID_IDebugSymbols,0x8c31e98c,0x983a,0x48a5,0x90,0x16,0x6f,0xe5,0xd6,0x67,0xa9,0x50);
	#endif

	template <class T>
	class print_trace_com_holder {
	private:
	T* holder_;

	private:
	print_trace_com_holder(const print_trace_com_holder&);
	print_trace_com_holder& operator=(const print_trace_com_holder&);

	public:
	print_trace_com_holder() USING_CXX11_NOEXCEPT : holder_(NULL) {}
	~print_trace_com_holder() USING_CXX11_NOEXCEPT {
	if (holder_) {
	holder_->Release();
	}
	}

	T* operator->() const USING_CXX11_NOEXCEPT {
	return holder_;
	}

	PVOID* to_pvoid_ptr() USING_CXX11_NOEXCEPT {
	return reinterpret_cast<PVOID*>(&holder_);
	}

	bool is_inited() const USING_CXX11_NOEXCEPT {
	return !!holder_;
	}
	};
	#endif

	void print_trace() USING_CXX11_NOEXCEPT {
	void * stack[ BACKTRACE_MAX_FRAME_NUMBER ];
	unsigned short frames;

	frames = CaptureStackBackTrace( 0, BACKTRACE_MAX_FRAME_NUMBER, stack, NULL );

	#if !defined(_MSC_VER)
	for(unsigned short i = 0; i < frames; i++ ) {
	printf( "Frame %02i: () [0x%p]\n", i, stack[ i ]);
	}

	#else // MSVC required flag: /DEBUG /Zi
	#if defined(USING_WIN_DBG_HELP) && USING_WIN_DBG_HELP
	SYMBOL_INFO * symbol;
	HANDLE process;
	DWORD64 displacement = 0;
	process = GetCurrentProcess();

	// SymSetOptions(SYMOPT_UNDNAME \| SYMOPT_DEFERRED_LOADS \| SYMOPT_LOAD_LINES);
	SymInitialize( process, NULL, TRUE );

	symbol = ( SYMBOL_INFO * )malloc(sizeof( SYMBOL_INFO ) + (MAX_SYM_NAME + 1) * sizeof(TCHAR));
	symbol->MaxNameLen = MAX_SYM_NAME;
	symbol->SizeOfStruct = sizeof( SYMBOL_INFO );

	for(unsigned short i = 0; i < frames; i++ ) {
	if(SymFromAddr( process, reinterpret_cast<ULONG64>(stack[i]), &displacement, symbol )) {
	printf( "Frame %02i: (%s) [0x%p]\n", i, &symbol->Name[0], symbol->Address );
	} else {
	printf( "Frame %02i: () [0x%p]\n", i, stack[i]);
	}
	}

	free(symbol);
	SymCleanup(process);
	#endif

	// ================== Using IDebugClient ==================
	#if defined(USING_WIN_DBG_ENG_COM) && USING_WIN_DBG_ENG_COM
	print_trace_com_holder<IDebugClient> dbg_cli;
	print_trace_com_holder<IDebugControl> dbg_ctrl;
	print_trace_com_holder<IDebugSymbols> dbg_sym;
	if (S_OK != ::DebugCreate(__uuidof(IDebugClient), dbg_cli.to_pvoid_ptr())) {
	return;
	}
	const bool res0 = (S_OK == dbg_cli->QueryInterface(
	__uuidof(IDebugControl),
	dbg_ctrl.to_pvoid_ptr()
	));
	if (!res0) {
	return;
	}

	const bool res1 = (S_OK == dbg_cli->AttachProcess(
	0,
	::GetCurrentProcessId(),
	DEBUG_ATTACH_NONINVASIVE \| DEBUG_ATTACH_NONINVASIVE_NO_SUSPEND
	));
	if (!res1) {
	return;
	}

	if (S_OK != dbg_ctrl->WaitForEvent(DEBUG_WAIT_DEFAULT, INFINITE)) {
	return;
	}

	// No cheking: QueryInterface sets the output parameter to NULL in case of error.
	dbg_cli->QueryInterface(__uuidof(IDebugSymbols), dbg_sym.to_pvoid_ptr());

	for(unsigned short i = 0; i < frames; i++ ) {
	if (!dbg_sym.is_inited()) {
	break;
	}

	const ULONG64 offset = reinterpret_cast<ULONG64>(stack[i]);

	char name[256];
	name[0] = '\0';
	ULONG size = 0;
	bool res = (S_OK == dbg_sym->GetNameByOffset(
	offset,
	name,
	sizeof(name),
	&size,
	0
	));

	std::string result;
	if (!res && size != 0) {
	result.resize(size);
	res = (S_OK == dbg_sym->GetNameByOffset(
	offset,
	&result[0],
	static_cast<ULONG>(result.size()),
	&size,
	0
	));
	} else if (res) {
	result = name;
	}

	printf( "Frame %02i: (%s) [0x%p]\n", i, result.c_str(), stack[i]);
	}
	#endif
	#endif
	}

	#else

	#if defined(USING_GNU_EXECINFO) && USING_GNU_EXECINFO
	#include <execinfo.h>
	#endif

	#if defined(USING_GNU_UNWIND) && USING_GNU_UNWIND
	#include <unwind.h>

	struct print_trace_unwind_state_t {
	size_t frames_to_skip;
	_Unwind_Word* current;
	_Unwind_Word* end;
	};

	static _Unwind_Reason_Code print_trace_unwind_callback(::_Unwind_Context* context, void* arg) {
	// Note: do not write `::_Unwind_GetIP` because it is a macro on some platforms.
	// Use `_Unwind_GetIP` instead!
	print_trace_unwind_state_t* const state = reinterpret_cast<print_trace_unwind_state_t*>(arg);
	if (state->frames_to_skip) {
	--state->frames_to_skip;
	return _Unwind_GetIP(context) ? ::_URC_NO_REASON : ::_URC_END_OF_STACK;
	}

	*state->current = _Unwind_GetIP(context);

	++state->current;
	if (!*(state->current - 1) \|\| state->current == state->end) {
	return ::_URC_END_OF_STACK;
	}

	return ::_URC_NO_REASON;
	}

	#endif

	/* Obtain a backtrace and print it to stdout. */

	struct print_trace_symbol_group_t {
	std::string module_name;
	std::string func_name;
	std::string func_offset;
	std::string func_address;
	};

	static const char* print_trace_skip_space(const char* name) {
	if (NULL == name) {
	return name;
	}

	while (name && (' ' == name \|\| '\r' == name \|\| '\t' == name \|\| '\r' == *name)) {
	++name;
	}

	return name;
	}

	inline bool print_trace_is_number_char(char c) {
	return c >= '0' && c <= '9';
	}

	inline bool print_trace_is_ident_char(char c) {
	return '_' == c \|\| '$' == c \|\| print_trace_is_number_char(c) \|\| (c >= 'a' && c <= 'z') \|\| (c >= 'A' && c <= 'Z') \|\| (c & 0x80);// utf-8 or unicode
	}

	static const char* print_trace_get_ident_end(const char* name) {
	if (NULL == name) {
	return name;
	}

	while (name && print_trace_is_ident_char(name)) {
	++ name;
	}

	return name;
	}

	static bool print_trace_pick_ident(const char* name, const char& start, const char& end, char& previous_c) {
	previous_c = 0;
	start = name;
	end = name;

	bool ret = false;
	if (NULL == name) {
	return false;
	}

	while(*name) {
	name = print_trace_skip_space(name);

	if (print_trace_is_ident_char(*name)) {
	start = name;
	end = print_trace_get_ident_end(name);
	ret = true;
	break;
	} else {
	previous_c = *name;
	++name;
	}
	}

	return ret;
	}

	static void print_trace_pick_symbol_info (const char* name, print_trace_symbol_group_t& out) {
	out.module_name.clear();
	out.func_name.clear();
	out.func_offset.clear();
	out.func_address.clear();

	if (NULL == name \|\| 0 == *name) {
	return;
	}

	name = print_trace_skip_space(name);
	while (name) {
	const char* start;
	char previous_c;

	if (print_trace_pick_ident(name, start, name, previous_c)) {
	if (print_trace_is_number_char(*start)) {
	if ('+' == previous_c) {
	out.func_offset = "+";
	out.func_offset.insert(out.func_offset.end(), start, name);
	} else {
	out.func_address.assign(start, name);
	}
	} else {
	if (out.module_name.empty()) {
	out.module_name.assign(start, name);
	} else {
	out.func_name.assign(start, name);
	}
	}
	} else {
	break;
	}

	name = print_trace_skip_space(name);
	}
	}

	void print_trace () {
	#if defined(USING_GNU_EXECINFO) && USING_GNU_EXECINFO
	{
	void *array[BACKTRACE_MAX_FRAME_NUMBER];
	size_t size;
	char **func_name_cache;

	size = backtrace (array, BACKTRACE_MAX_FRAME_NUMBER);
	func_name_cache = backtrace_symbols (array, size);

	for (size_t i = 0; i < size; i++) {
	print_trace_symbol_group_t symbol;
	print_trace_pick_symbol_info(func_name_cache[i], symbol);

	#if defined(USING_LIBSTDCXX_ABI) \|\| defined(USING_LIBCXX_ABI)
	if (!symbol.func_name.empty()) {
	int cxx_abi_status;
	char* realfunc_name = abi::__cxa_demangle(symbol.func_name.c_str(), 0, 0, &cxx_abi_status);
	if (NULL != realfunc_name) {
	symbol.func_name = realfunc_name;
	}

	if (NULL != realfunc_name) {
	free(realfunc_name);
	}
	}
	#endif

	printf("Frame #%02d: (%s%s) [%s]\n", static_cast<int>(i), symbol.func_name.c_str(), symbol.func_offset.c_str(), symbol.func_address.c_str());
	}

	free (func_name_cache);
	}
	#endif

	#if defined(USING_GNU_UNWIND) && USING_GNU_UNWIND
	{
	_Unwind_Word stacks[BACKTRACE_MAX_FRAME_NUMBER];
	print_trace_unwind_state_t state;
	state.frames_to_skip = 0;
	state.current = stacks;
	state.end = stacks + BACKTRACE_MAX_FRAME_NUMBER;

	::_Unwind_Backtrace(&print_trace_unwind_callback, &state);
	size_t frames_count = state.current - &stacks[0];
	for (size_t i = 0; i < frames_count; ++ i) {
	printf("Frame #%02d: () [0x%lx]\n", static_cast<int>(i), stacks[i]);
	}
	}
	#endif
	}
	#endif

	#endif

	void func1(int times) {
	if (times > 0) {
	func1(times - 1);
	return;
	}

	print_trace();
	}

	class functor2 {
	public:
	void func2(int times) {
	if (times & 0x01) {
	func2(times - 1);
	} else {
	func1(times - 1);
	}
	}
	};

	class functor3 {
	public:
	static void func3(int times) {
	if (times & 0x01) {
	func3(times - 1);
	} else {
	functor2 f;
	f.func2(times - 1);
	}
	}
	};

	struct functor4 {
	void operator()(int times) {
	if (times & 0x01) {
	(*this)(times - 1);
	} else {
	functor3::func3(times - 1);
	}
	}
	};

	static void func5(int times) {
	if (times & 0x01) {
	func5(times - 1);
	} else {
	functor4 f;
	f(times - 1);
	}
	}

	void func6(int times) {
	if (times & 0x01) {
	func6(times - 1);
	} else {
	func5(times - 1);
	}
	}

	int main (int argc, char* argv[]) {
	int times = 15;
	if (argc > 1) {
	times = atoi(argv[1]);
	}
	func6(times);
	return 0;
	}