我正在将一个库与opencv库链接起来。我注意到当我为该库运行单元测试可执行文件（使用GTest）时，valgrind报告内存泄漏/条件跳转或移动取决于未初始化的值，即使测试根本没有做任何事情（只是空测试方法） ）。
我将这个问题追溯到我的CMakeLists.txt中的一行 - 当我删除与opencv的链接时，内存泄漏消失了。这是一个重要的片段：
find_package(OpenCV REQUIRED)
set(libImageSources src/SourceImageFile.cpp)
add_library(image SHARED ${libImageSources})
# removing this line fixes the leak:
target_link_libraries(image ${OpenCV_LIBS})
否则当runnig空单元测试时，我会收到如下错误：
==18681== Memcheck, a memory error detector
==18681== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
==18681== Using Valgrind-3.11.0 and LibVEX; rerun with -h for copyright info
==18681== Command: ./image_test /Users/max/Documents/playground/cpp/image-server/tests
==18681==
==18681== Conditional jump or move depends on uninitialised value(s)
==18681== at 0x7FFF5FC24A27: bcmp (in /usr/lib/dyld)
==18681== by 0x7FFF5FC11904: ImageLoaderMachO::validateFirstPages(linkedit_data_command const*, int, unsigned char const*, unsigned long, long long, ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC16B7A: ImageLoaderMachOCompressed::instantiateFromFile(char const*, int, unsigned char const*, unsigned long, unsigned long long, unsigned long long, stat const&, unsigned int, unsigned int, linkedit_data_command const*, encryption_info_command const*, ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC10A6E: ImageLoaderMachO::instantiateFromFile(char const*, int, unsigned char const*, unsigned long long, unsigned long long, stat const&, ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC038C2: dyld::loadPhase6(int, stat const&, char const*, dyld::LoadContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC08468: dyld::loadPhase5(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC08188: dyld::loadPhase4(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC07EED: dyld::loadPhase3(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC07642: dyld::loadPhase1(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC0347A: dyld::loadPhase0(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC0315E: dyld::load(char const*, dyld::LoadContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC08705: dyld::libraryLocator(char const*, bool, char const*, ImageLoader::RPathChain const*) (in /usr/lib/dyld)
==18681==
==18681== Use of uninitialised value of size 8
==18681== at 0x7FFF5FC24A3F: bcmp (in /usr/lib/dyld)
==18681== by 0x7FFF5FC11904: ImageLoaderMachO::validateFirstPages(linkedit_data_command const*, int, unsigned char const*, unsigned long, long long, ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC16B7A: ImageLoaderMachOCompressed::instantiateFromFile(char const*, int, unsigned char const*, unsigned long, unsigned long long, unsigned long long, stat const&, unsigned int, unsigned int, linkedit_data_command const*, encryption_info_command const*, ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC10A6E: ImageLoaderMachO::instantiateFromFile(char const*, int, unsigned char const*, unsigned long long, unsigned long long, stat const&, ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC038C2: dyld::loadPhase6(int, stat const&, char const*, dyld::LoadContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC08468: dyld::loadPhase5(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC08188: dyld::loadPhase4(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC07EED: dyld::loadPhase3(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC07642: dyld::loadPhase1(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC0347A: dyld::loadPhase0(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC0315E: dyld::load(char const*, dyld::LoadContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC08705: dyld::libraryLocator(char const*, bool, char const*, ImageLoader::RPathChain const*) (in /usr/lib/dyld)
==18681==
==18681== Use of uninitialised value of size 8
==18681== at 0x7FFF5FC24A44: bcmp (in /usr/lib/dyld)
==18681== by 0x7FFF5FC11904: ImageLoaderMachO::validateFirstPages(linkedit_data_command const*, int, unsigned char const*, unsigned long, long long, ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC16B7A: ImageLoaderMachOCompressed::instantiateFromFile(char const*, int, unsigned char const*, unsigned long, unsigned long long, unsigned long long, stat const&, unsigned int, unsigned int, linkedit_data_command const*, encryption_info_command const*, ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC10A6E: ImageLoaderMachO::instantiateFromFile(char const*, int, unsigned char const*, unsigned long long, unsigned long long, stat const&, ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC038C2: dyld::loadPhase6(int, stat const&, char const*, dyld::LoadContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC08468: dyld::loadPhase5(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC08188: dyld::loadPhase4(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC07EED: dyld::loadPhase3(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC07642: dyld::loadPhase1(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC0347A: dyld::loadPhase0(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC0315E: dyld::load(char const*, dyld::LoadContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC08705: dyld::libraryLocator(char const*, bool, char const*, ImageLoader::RPathChain const*) (in /usr/lib/dyld)
==18681==
==18681== Conditional jump or move depends on uninitialised value(s)
==18681== at 0x7FFF5FC11907: ImageLoaderMachO::validateFirstPages(linkedit_data_command const*, int, unsigned char const*, unsigned long, long long, ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC16B7A: ImageLoaderMachOCompressed::instantiateFromFile(char const*, int, unsigned char const*, unsigned long, unsigned long long, unsigned long long, stat const&, unsigned int, unsigned int, linkedit_data_command const*, encryption_info_command const*, ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC10A6E: ImageLoaderMachO::instantiateFromFile(char const*, int, unsigned char const*, unsigned long long, unsigned long long, stat const&, ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC038C2: dyld::loadPhase6(int, stat const&, char const*, dyld::LoadContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC08468: dyld::loadPhase5(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC08188: dyld::loadPhase4(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC07EED: dyld::loadPhase3(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC07642: dyld::loadPhase1(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC0347A: dyld::loadPhase0(char const*, char const*, dyld::LoadContext const&, std::__1::vector<char const*, std::__1::allocator<char const*> >*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC0315E: dyld::load(char const*, dyld::LoadContext const&) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC08705: dyld::libraryLocator(char const*, bool, char const*, ImageLoader::RPathChain const*) (in /usr/lib/dyld)
==18681== by 0x7FFF5FC0E85D: ImageLoader::recursiveLoadLibraries(ImageLoader::LinkContext const&, bool, ImageLoader::RPathChain const&) (in /usr/lib/dyld)
==18681==
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from ImageProcessingConfigurationService
[ RUN ] ImageProcessingConfigurationService.evaluateConfigurationFile
[ OK ] ImageProcessingConfigurationService.evaluateConfigurationFile (13 ms)
[----------] 1 test from ImageProcessingConfigurationService (28 ms total)
[----------] Global test environment tear-down
[==========] 1 test from 1 test case ran. (114 ms total)
[ PASSED ] 1 test.
==18681==
==18681== HEAP SUMMARY:
==18681== in use at exit: 1,346,030 bytes in 1,453 blocks
==18681== total heap usage: 2,926 allocs, 1,473 frees, 3,045,052 bytes allocated
==18681==
==18681== LEAK SUMMARY:
==18681== definitely lost: 10,580 bytes in 137 blocks
==18681== indirectly lost: 10,032 bytes in 152 blocks
==18681== possibly lost: 9,568 bytes in 183 blocks
==18681== still reachable: 43,598 bytes in 520 blocks
==18681== suppressed: 1,272,252 bytes in 461 blocks
==18681== Rerun with --leak-check=full to see details of leaked memory
==18681==
==18681== For counts of detected and suppressed errors, rerun with: -v
==18681== Use --track-origins=yes to see where uninitialised values come from
==18681== ERROR SUMMARY: 36 errors from 4 contexts (suppressed: 0 from 0)
编译器是clang ++ Apple LLVM版本7.3.0（clang-703.0.31），OS X El Capitan（10.11.1）。
其他人有这样的问题吗？似乎东西仍然有效，但错误会产生我宁愿忽略的噪音，我不确定我是否能解决根本原因。
答案 0 :(得分：0)
这个问题似乎是valgrind报告的误报，我可以忽略它，因为它不是由代码引起的。
我尝试（在撰写本文时）最新的valgrind suppressions file for macOS这对我不起作用，但问题仍然存在。
我让valgrind dump the suppressions需要忽略此错误，使用如下命令：
valgrind --leak-check=full --show-reachable=yes --error-limit=no --gen-suppressions=all --log-file=l.log ./image_test
然后使用a tool to parse the log output（awk脚本对我不起作用，因为它包含语法错误，我使用了perl版本）到一个抑制文件中：
cat l.log | ./parse_valgrind_suppressions.pl > s.supp
现在使用生成的suppresions文件运行测试会忽略内存泄漏：
valgrind --suppressions=./s.supp ./image_test