c++ - 应用编译器优化时，google breakpad 堆栈跟踪中没有符号

Question

崩溃报告工具的要点，如 Google breakpad是从剥离的二进制文件中生成核心转储或小型转储文件，以便稍后使用调试符号进行处理。通常这些二进制文件是应用了编译器优化的发布版本，也被剥离了。
要在 Linux 上重现该问题:
1.构建+安装google breakpad:

git clone https://chromium.googlesource.com/breakpad/breakpad && cd breakpad
git clone https://chromium.googlesource.com/linux-syscall-support src/third_party/lss
./configure --prefix=/usr/local
make -j$(nproc) && sudo make install

2.代码: CMakeLists.txt :

cmake_minimum_required(VERSION 3.10)

project(BreakPadTest)

set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_VERBOSE_MAKEFILE TRUE)
set(BREAKPAD_DIR "/usr/local/include/breakpad")
   
option(OPTION_WITH_O1 "With -O1" OFF)
if(OPTION_WITH_O1)
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O1 -fno-omit-frame-pointer")
endif()

include_directories(
    ${BREAKPAD_DIR}
    )

add_executable(${PROJECT_NAME} "main.cc")

target_link_libraries(${PROJECT_NAME}
    -lstdc++fs
    -pthread
    libbreakpad_client.a
    )

main.cc :

#include <thread>
#include <experimental/filesystem>

#include <client/linux/handler/exception_handler.h>

namespace breakpad = google_breakpad;
namespace filesystem = std::experimental::filesystem;

static bool DumpCallBack(const breakpad::MinidumpDescriptor& md,
                         void* context,
                         bool success) {
    (void)md;
    (void)context;
    return success;
}

static void fault(unsigned after) {
    std::this_thread::sleep_for(std::chrono::seconds{after});
    delete reinterpret_cast<std::string*>(0xFEE1DEAD);
}

int32_t main(int argc, char** argv) {
    (void)argc;
    (void)argv;

    auto pwd = filesystem::current_path();
    const auto dumpDir = pwd.string() + "/dumps";
    filesystem::create_directory(dumpDir);
    breakpad::MinidumpDescriptor md(dumpDir);
    new google_breakpad::ExceptionHandler(
        md,
        /* FilterCallback */ nullptr,
        DumpCallBack,
        /* callback_context */ nullptr,
        true,
        -1
    );

    fault(1U);

    return EXIT_SUCCESS;
}

dump.sh :

#!/bin/bash

#
# e.g ./dump.sh ./exec $PWD/dumps
#

set -e
set -u

DBG_INFO=$(realpath ${1})
DUMPS_DIR=$(realpath ${2:-$PWD/dumps})
DUMP_SYMS=${3:-~/WorkSpace/libraries/breakpad/src/tools/linux/dump_syms/dump_syms}
STAK_WALK=${4:-~/WorkSpace/libraries/breakpad/src/processor/minidump_stackwalk}

#
# Generate debug symbols
#
base=$(basename $DBG_INFO)
$DUMP_SYMS $DBG_INFO > $DUMPS_DIR/$base.sym

#
# Create dump dir structure
#
list=($(head -n1 $DUMPS_DIR/$base.sym))
hash=${list[3]}
mkdir -p $DUMPS_DIR/symbols/$base/$hash
mv $DUMPS_DIR/$base.sym $DUMPS_DIR/symbols/$base/$hash

#
# Produce stack trace
#
RED='\033[0;36m'
NC='\033[0m' # No Color
tree $DUMPS_DIR
for dmp in $DUMPS_DIR/*.dmp ; do
    filename=$(basename -- "${dmp}")
    filename="${filename%.*}"
    echo -e "generating stack trace for -> ${RED}${dmp}${NC}"
    $STAK_WALK ${dmp} $DUMPS_DIR/symbols > $DUMPS_DIR/${filename}.txt 2>/dev/null
done

3.运行正常 Debug版本:

cmake -DCMAKE_BUILD_TYPE=Debug . && make
./BreakPadTest 

4.处理第 3 阶段生成的小型转储:

./dump.sh ./BreakPadTest ./dumps

stackwalk :

Operating system: Linux
                  0.0.0 Linux 4.19.0-16-amd64 #1 SMP Debian 4.19.181-1 (2021-03-19) x86_64
CPU: amd64
     family 6 model 58 stepping 9
     1 CPU

GPU: UNKNOWN

Crash reason:  SIGSEGV /SEGV_MAPERR
Crash address: 0xfee1dead
Process uptime: not available

Thread 0 (crashed)
 0  BreakPadTest!std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_data() const [basic_string.h : 176 + 0x4]
    rax = 0x00000000fee1dead   rdx = 0x00007ffcfccfcb90
    rcx = 0x00007f5b0cbb4bc1   rbx = 0x0000557d577eb8e0
    rsi = 0x00007ffcfccfcb90   rdi = 0x00000000fee1dead
    rbp = 0x00007ffcfccfcb50   rsp = 0x00007ffcfccfcb50
     r8 = 0x0000000000000000    r9 = 0x0000557d577efaf8
    r10 = 0xfffffffffffff60b   r11 = 0x0000000000000246
    r12 = 0x0000557d56d3d2c0   r13 = 0x00007ffcfccfce50
    r14 = 0x0000000000000000   r15 = 0x0000000000000000
    rip = 0x0000557d56d3dfda
    Found by: given as instruction pointer in context
 1  BreakPadTest!std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_is_local() const [basic_string.h : 211 + 0xc]
    rbx = 0x0000557d577eb8e0   rbp = 0x00007ffcfccfcb80
    rsp = 0x00007ffcfccfcb60   r12 = 0x0000557d56d3d2c0
    r13 = 0x00007ffcfccfce50   r14 = 0x0000000000000000
    r15 = 0x0000000000000000   rip = 0x0000557d56d3e2c5
    Found by: call frame info
 2  BreakPadTest!std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::_M_dispose() [basic_string.h : 220 + 0xc]
    rbx = 0x0000557d577eb8e0   rbp = 0x00007ffcfccfcba0
    rsp = 0x00007ffcfccfcb90   r12 = 0x0000557d56d3d2c0
    r13 = 0x00007ffcfccfce50   r14 = 0x0000000000000000
    r15 = 0x0000000000000000   rip = 0x0000557d56d3dff8
    Found by: call frame info
 3  BreakPadTest!std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::~basic_string() [basic_string.h : 657 + 0xc]
    rbx = 0x0000557d577eb8e0   rbp = 0x00007ffcfccfcbc0
    rsp = 0x00007ffcfccfcbb0   r12 = 0x0000557d56d3d2c0
    r13 = 0x00007ffcfccfce50   r14 = 0x0000000000000000
    r15 = 0x0000000000000000   rip = 0x0000557d56d3d930
    Found by: call frame info
 4  BreakPadTest!fault [main.cc : 19 + 0xa]
    rbx = 0x0000557d577eb8e0   rbp = 0x00007ffcfccfcbf0
    rsp = 0x00007ffcfccfcbd0   r12 = 0x0000557d56d3d2c0
    r13 = 0x00007ffcfccfce50   r14 = 0x0000000000000000
    r15 = 0x0000000000000000   rip = 0x0000557d56d3d3f0
    Found by: call frame info
 5  BreakPadTest!main [main.cc : 39 + 0xa]
    rbx = 0x0000557d577eb8e0   rbp = 0x00007ffcfccfcd70
    rsp = 0x00007ffcfccfcc00   r12 = 0x0000557d56d3d2c0
    r13 = 0x00007ffcfccfce50   r14 = 0x0000000000000000
    r15 = 0x0000000000000000   rip = 0x0000557d56d3d4fd
    Found by: call frame info
 6  libc.so.6 + 0x2409b
    rbx = 0x0000000000000000   rbp = 0x0000557d56d78b80
    rsp = 0x00007ffcfccfcd80   r12 = 0x0000557d56d3d2c0
    r13 = 0x00007ffcfccfce50   r14 = 0x0000000000000000
    r15 = 0x0000000000000000   rip = 0x00007f5b0ca0609b
    Found by: call frame info
 7  BreakPadTest!fault [main.cc : 20 + 0x3]
    rsp = 0x00007ffcfccfcda0   rip = 0x0000557d56d3d402
    Found by: stack scanning
 8  ld-linux-x86-64.so.2 + 0xf476
    rsp = 0x00007ffcfccfce10   rip = 0x00007f5b0cf1c476
    Found by: stack scanning
 9  BreakPadTest!_start + 0x2a
    rsp = 0x00007ffcfccfce40   rip = 0x0000557d56d3d2ea
    Found by: stack scanning
10  0x7ffcfccfce48
    rsp = 0x00007ffcfccfce48   rip = 0x00007ffcfccfce48
    Found by: call frame info

Loaded modules:
0x557d56d34000 - 0x557d56d78fff  BreakPadTest  ???  (main)
0x7f5b0c9e2000 - 0x7f5b0cb4bfff  libc.so.6  ???  (WARNING: No symbols, libc.so.6, A8A9B91823C5CFE5E5B5D946D605D0920)
0x7f5b0cba3000 - 0x7f5b0cbb7fff  libpthread.so.0  ???
0x7f5b0cbc4000 - 0x7f5b0cbd7fff  libgcc_s.so.1  ???
0x7f5b0cbde000 - 0x7f5b0cc89fff  libm.so.6  ???
0x7f5b0cd61000 - 0x7f5b0ce95fff  libstdc++.so.6  ???
0x7f5b0cf0d000 - 0x7f5b0cf2bfff  ld-linux-x86-64.so.2  ???  (WARNING: No symbols, ld-linux-x86-64.so.2, 7BFD5DF2BE95A34B86FD71080ACCAE8C0)
0x7ffcfcdc5000 - 0x7ffcfcdc6fff  linux-gate.so  ???

5.使用 -O1 运行第 3 阶段:

cmake -DCMAKE_BUILD_TYPE=Debug -DOPTION_WITH_O1=ON . && make
./BreakPadTest

6. 像阶段 4 一样处理小型转储: stackwalk :

Operating system: Linux
                  0.0.0 Linux 4.19.0-16-amd64 #1 SMP Debian 4.19.181-1 (2021-03-19) x86_64
CPU: amd64
     family 6 model 58 stepping 9
     1 CPU

GPU: UNKNOWN

Crash reason:  SIGSEGV /SEGV_MAPERR
Crash address: 0xfee1dead
Process uptime: not available

Thread 0 (crashed)
 0  BreakPadTest!main [basic_string.h : 176 + 0x0]
    rax = 0x0000000000000000   rdx = 0x000055bd46f66a40
    rcx = 0x00007f7633ea8bc1   rbx = 0x00007ffde4cc7c40
    rsi = 0x00007ffde4cc7c40   rdi = 0x00007ffde4cc7c40
    rbp = 0x00007ffde4cc7d90   rsp = 0x00007ffde4cc7c20
     r8 = 0x0000000000000000    r9 = 0x000055bd474caaf8
    r10 = 0x0000000000000000   r11 = 0x0000000000000246
    r12 = 0x000055bd474c64f0   r13 = 0x000055bd474c64f0
    r14 = 0x0000000000000000   r15 = 0x0000000000000000
    rip = 0x000055bd46f1b8dd
    Found by: given as instruction pointer in context
 1  libc.so.6 + 0x2409b
    rbx = 0x0000000000000000   rbp = 0x000055bd46f555e0
    rsp = 0x00007ffde4cc7da0   r12 = 0x000055bd46f1b270
    r13 = 0x00007ffde4cc7e70   r14 = 0x0000000000000000
    r15 = 0x0000000000000000   rip = 0x00007f7633cfa09b
    Found by: call frame info
 2  BreakPadTest!DumpCallBack [main.cc : 15 + 0x3]
    rsp = 0x00007ffde4cc7dc0   rip = 0x000055bd46f1b358
    Found by: stack scanning
 3  ld-linux-x86-64.so.2 + 0xf476
    rsp = 0x00007ffde4cc7e30   rip = 0x00007f7634210476
    Found by: stack scanning
 4  BreakPadTest!_start + 0x2a
    rsp = 0x00007ffde4cc7e60   rip = 0x000055bd46f1b29a
    Found by: stack scanning
 5  0x7ffde4cc7e68
    rsp = 0x00007ffde4cc7e68   rip = 0x00007ffde4cc7e68
    Found by: call frame info

Loaded modules:
0x55bd46f14000 - 0x55bd46f55fff  BreakPadTest  ???  (main)
0x7f7633cd6000 - 0x7f7633e3ffff  libc.so.6  ???  (WARNING: No symbols, libc.so.6, A8A9B91823C5CFE5E5B5D946D605D0920)
0x7f7633e97000 - 0x7f7633eabfff  libpthread.so.0  ???
0x7f7633eb8000 - 0x7f7633ecbfff  libgcc_s.so.1  ???
0x7f7633ed2000 - 0x7f7633f7dfff  libm.so.6  ???
0x7f7634055000 - 0x7f7634189fff  libstdc++.so.6  ???
0x7f7634201000 - 0x7f763421ffff  ld-linux-x86-64.so.2  ???  (WARNING: No symbols, ld-linux-x86-64.so.2, 7BFD5DF2BE95A34B86FD71080ACCAE8C0)
0x7ffde4d9a000 - 0x7ffde4d9bfff  linux-gate.so  ???

正如我们所看到的，正确的符号从第 6 阶段的堆栈遍历中消失了。
而在其他工具中，如 GDB即使在阶段 5 中使用 -O1，我们也有正确的跟踪指向正确的位置:

Program received signal SIGSEGV, Segmentation fault.
fault (after=1) at /home/iman/WorkSpace/projects/BreakPadTest/src/main.cc:26
26      delete reinterpret_cast<std::string*>(0xFEE1DEAD);

或者在其他工具中，例如 backward-cpp :

Stack trace (most recent call last):
#3    Object "", at 0xffffffffffffffff, in 
#2    Object "/home/iman/WorkSpace/projects/build-CrashReporter-Desktop_Qt_5_11_3_GCC-Debug/CrashReporter", at 0x55f32a66b579, in _start
#1    Source "/build/glibc-vjB4T1/glibc-2.28/csu/../csu/libc-start.c", line 308, in __libc_start_main [0x7f56288be09a]
#0  | Source "/home/iman/WorkSpace/projects/BreakPadTest/src/main.cc", line 48, in main
    |    46: #endif // WITH_BREAKPAD
    |    47: 
    | >  48:     fault(1U);
    |    49: 
    |    50:     return EXIT_SUCCESS;
    | Source "/home/iman/WorkSpace/projects/BreakPadTest/src/main.cc", line 26, in fault
    |    24: static void fault(unsigned after) {
    |    25:     std::this_thread::sleep_for(std::chrono::seconds{after});
    | >  26:     delete reinterpret_cast<std::string*>(0xFEE1DEAD);
    |    27: }
    | Source "/usr/include/c++/8/bits/basic_string.h", line 657, in 
    |   655:        */
    |   656:       ~basic_string()
    | > 657:       { _M_dispose(); }
    |   658: 
    |   659:       /**
    | Source "/usr/include/c++/8/bits/basic_string.h", line 220, in 
    |   218:       _M_dispose()
    |   219:       {
    | > 220:    if (!_M_is_local())
    |   221:      _M_destroy(_M_allocated_capacity);
    |   222:       }
    | Source "/usr/include/c++/8/bits/basic_string.h", line 211, in 
    |   209:       bool
    |   210:       _M_is_local() const
    | > 211:       { return _M_data() == _M_local_data(); }
    |   212: 
    |   213:       // Create & Destroy
      Source "/usr/include/c++/8/bits/basic_string.h", line 176, in main [0x55f32a66b66c]
        174:       pointer
        175:       _M_data() const
      > 176:       { return _M_dataplus._M_p; }
        177: 
        178:       pointer
        179:       _M_local_data()
Segmentation fault (Address not mapped to object [0xfee1dead])
Segmentation fault

任何想法或提示？

Answer 1

用优化 -O1 几乎所有 std::basic_string函数是内联的。这些函数是内联的，因为 std::basic_string是一个模板并在 heder 文件中定义。