Valgrind——堆统计很奇怪：内存泄漏？答案

【问题标题】：Valgrind — heap stats are weird: memory leak?Valgrind——堆统计很奇怪：内存泄漏？
【发布时间】：2015-12-01 00:25:53
【问题描述】：

Valgrind 给了我非常高的空闲、分配和分配的字节数，并且没有意识到我已经释放了堆中的内存。

#include <stdio.h>
#include <stdlib.h>

int main(){
    return 0;
}

gcc -std=c99 -g -Werror -Wextra -pedantic valgrind.c
valgrind --leak-check=full ./a.out
==44611== Memcheck, a memory error detector
==44611== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
==44611== Using Valgrind-3.11.0 and LibVEX; rerun with -h for copyright info
==44611== Command: ./a.out
==44611== 
==44611== 
==44611== HEAP SUMMARY:
==44611==     in use at exit: 22,223 bytes in 183 blocks
==44611==   total heap usage: 259 allocs, 76 frees, 28,335 bytes allocated
==44611== 
==44611== LEAK SUMMARY:
==44611==    definitely lost: 0 bytes in 0 blocks
==44611==    indirectly lost: 0 bytes in 0 blocks
==44611==      possibly lost: 0 bytes in 0 blocks
==44611==    still reachable: 0 bytes in 0 blocks
==44611==         suppressed: 22,223 bytes in 183 blocks
==44611== 
==44611== For counts of detected and suppressed errors, rerun with: -v
==44611== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 16 from 16)

它告诉我我有259 allocs, 76 frees, 28,335 bytes allocated，当我的程序中几乎没有任何内容时，这太疯狂了。我很害怕我以前从未释放分配空间的日子造成了内存泄漏。如果是这样，知道如何在我的 Mac 上回收以前分配的内存吗？我正在使用 El Capitan。

【问题讨论】：

你return 在free 之前。编译器应该告诉你free 是不可访问的。
感谢您解决这部分问题
欢迎使用 Mac OS X。使用 --leak-check=full（可能与 --num-callers=100）检查泄漏是否超出您的控制，然后使用 --gen-suppressions=all 将抑制生成到文件中，然后然后用--suppressions=suppresions-file 重新运行，看看它们都已经消失了。 OSX 启动代码完成了大量内存分配。
@JonathanLeffler 这会释放所有分配的内存吗？我在 valgrind 中输入这个吗？
你看到的数字是C库实现使用的静态对象，不用担心

标签： c macos memory-leaks valgrind

【解决方案1】：

正如我在评论中指出的，这对于 Mac OS X 来说是半正常的，至少在您调整系统之前是这样。我不得不为 El Capitan 添加很多抑制（由 Valgrind 生成）。

首先要注意的是您的代码不分配内存，因此您的代码不可能泄漏任何内存。任何泄露或可能泄露的内容都是由操作系统在您的程序启动之前完成的。

接下来要注意的是，即使您决定担心它，也无需担心太多，或者您可以做些什么。到目前为止，您最好的选择是让 Valgrind 知道您知道这一点并继续生活。

那么，你如何告诉 Valgrind？

Stage 1 使用 --leak-check=full 和 --num-callers=100 运行 Valgrind。例如，在我的 El Capitan 上运行你的程序为leaks.c，我得到：

==43058== Memcheck, a memory error detector
==43058== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.
==43058== Using Valgrind-3.11.0.SVN and LibVEX; rerun with -h for copyright info
==43058== Command: leaks
==43058== 
--43058-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option
--43058-- UNKNOWN fcntl 97!
--43058-- UNKNOWN fcntl 97! (repeated 2 times)
--43058-- UNKNOWN fcntl 97! (repeated 4 times)
--43058-- UNKNOWN fcntl 97! (repeated 8 times)
--43058-- UNKNOWN fcntl 97! (repeated 16 times)
--43058-- UNKNOWN fcntl 97! (repeated 32 times)
--43058-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option (repeated 2 times)
--43058-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option (repeated 4 times)
--43058-- UNKNOWN task message [id 3406, to mach_task_self(), reply 0x60f]
--43058-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option (repeated 8 times)
--43058-- UNKNOWN host message [id 412, to mach_host_self(), reply 0x60f]
--43058-- UNKNOWN host message [id 222, to mach_host_self(), reply 0x60f]
--43058-- UNKNOWN task message [id 3410, to mach_task_self(), reply 0x60f]
==43058== 
==43058== HEAP SUMMARY:
==43058==     in use at exit: 22,245 bytes in 187 blocks
==43058==   total heap usage: 263 allocs, 76 frees, 28,341 bytes allocated
==43058== 
==43058== LEAK SUMMARY:
==43058==    definitely lost: 4,416 bytes in 4 blocks
==43058==    indirectly lost: 2,288 bytes in 6 blocks
==43058==      possibly lost: 7,096 bytes in 68 blocks
==43058==    still reachable: 8,445 bytes in 109 blocks
==43058==         suppressed: 0 bytes in 0 blocks
==43058== Rerun with --leak-check=full to see details of leaked memory
==43058== 
==43058== For counts of detected and suppressed errors, rerun with: -v
==43058== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)

我不喜欢那些UNKNOWN 消息，但这可能意味着我需要重建。请注意，我从 SVN 获得了代码——查看版本号。

现在，再次运行：

$ valgrind --num-callers=100 --leak-check=full ./leaks

==43059== Memcheck, a memory error detector
==43059== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.
==43059== Using Valgrind-3.11.0.SVN and LibVEX; rerun with -h for copyright info
==43059== Command: ./leaks
==43059== 
--43059-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option
--43059-- UNKNOWN fcntl 97!
--43059-- UNKNOWN fcntl 97! (repeated 2 times)
--43059-- UNKNOWN fcntl 97! (repeated 4 times)
--43059-- UNKNOWN fcntl 97! (repeated 8 times)
--43059-- UNKNOWN fcntl 97! (repeated 16 times)
--43059-- UNKNOWN fcntl 97! (repeated 32 times)
--43059-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option (repeated 2 times)
--43059-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option (repeated 4 times)
--43059-- UNKNOWN task message [id 3406, to mach_task_self(), reply 0x60f]
--43059-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option (repeated 8 times)
--43059-- UNKNOWN host message [id 412, to mach_host_self(), reply 0x60f]
--43059-- UNKNOWN host message [id 222, to mach_host_self(), reply 0x60f]
--43059-- UNKNOWN task message [id 3410, to mach_task_self(), reply 0x60f]
==43059== 
==43059== HEAP SUMMARY:
==43059==     in use at exit: 22,245 bytes in 187 blocks
==43059==   total heap usage: 263 allocs, 76 frees, 28,341 bytes allocated
==43059== 
==43059== 24 bytes in 1 blocks are possibly lost in loss record 9 of 62
==43059==    at 0x100006355: malloc_zone_calloc (vg_replace_malloc.c:632)
==43059==    by 0x1004FE4B1: NXHashInsert (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x1004FE1BE: NXCreateHashTableFromZone (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x1004FE053: NXCreateHashTable (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x1004FD037: _read_images (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x1004FBB4D: map_images_nolock (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x1004FB538: map_2_images (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x7FFF5FC047CF: dyld::notifyBatchPartial(dyld_image_states, bool, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC04516: dyld::registerImageStateBatchChangeHandler(dyld_image_states, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==43059==    by 0x10016689D: dyld_register_image_state_change_handler (in /usr/lib/system/libdyld.dylib)
==43059==    by 0x1004FB07A: _objc_init (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x10010EC4B: _os_object_init (in /usr/lib/system/libdispatch.dylib)
==43059==    by 0x10010EC37: libdispatch_init (in /usr/lib/system/libdispatch.dylib)
==43059==    by 0x100010A01: libSystem_initializer (in /usr/lib/libSystem.B.dylib)
==43059==    by 0x7FFF5FC12F1A: ImageLoaderMachO::doModInitFunctions(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC13093: ImageLoaderMachO::doInitialization(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC0F6CC: ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC0F661: ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC0F552: ImageLoader::processInitializers(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC0F7C2: ImageLoader::runInitializers(ImageLoader::LinkContext const&, ImageLoader::InitializerTimingList&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC020AA: dyld::initializeMainExecutable() (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC05D46: dyld::_main(macho_header const*, unsigned long, int, char const**, char const**, char const**, unsigned long*) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC01275: dyldbootstrap::start(macho_header const*, int, char const**, long, macho_header const*, unsigned long*) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC01035: _dyld_start (in /usr/lib/dyld)
==43059== 
==43059== 24 bytes in 1 blocks are possibly lost in loss record 10 of 62
==43059==    at 0x100006355: malloc_zone_calloc (vg_replace_malloc.c:632)
==43059==    by 0x1004FE4B1: NXHashInsert (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x100500223: realizeClass(objc_class*) (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x1004FD90C: _read_images (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x1004FBB4D: map_images_nolock (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x1004FB538: map_2_images (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x7FFF5FC047CF: dyld::notifyBatchPartial(dyld_image_states, bool, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC04516: dyld::registerImageStateBatchChangeHandler(dyld_image_states, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==43059==    by 0x10016689D: dyld_register_image_state_change_handler (in /usr/lib/system/libdyld.dylib)
==43059==    by 0x1004FB07A: _objc_init (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x10010EC4B: _os_object_init (in /usr/lib/system/libdispatch.dylib)
==43059==    by 0x10010EC37: libdispatch_init (in /usr/lib/system/libdispatch.dylib)
==43059==    by 0x100010A01: libSystem_initializer (in /usr/lib/libSystem.B.dylib)
==43059==    by 0x7FFF5FC12F1A: ImageLoaderMachO::doModInitFunctions(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC13093: ImageLoaderMachO::doInitialization(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC0F6CC: ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC0F661: ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC0F552: ImageLoader::processInitializers(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC0F7C2: ImageLoader::runInitializers(ImageLoader::LinkContext const&, ImageLoader::InitializerTimingList&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC020AA: dyld::initializeMainExecutable() (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC05D46: dyld::_main(macho_header const*, unsigned long, int, char const**, char const**, char const**, unsigned long*) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC01275: dyldbootstrap::start(macho_header const*, int, char const**, long, macho_header const*, unsigned long*) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC01035: _dyld_start (in /usr/lib/dyld)
==43059== 

…lots of text missing…

==43059== 
==43059== 4,096 bytes in 1 blocks are definitely lost in loss record 62 of 62
==43059==    at 0x100007110: malloc_zone_memalign (vg_replace_malloc.c:769)
==43059==    by 0x100504D71: (anonymous namespace)::AutoreleasePoolPage::autoreleaseNoPage(objc_object*) (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x100504CF5: objc_autoreleasePoolPush (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x100504998: call_load_methods (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x100501B9D: load_images (in /usr/lib/libobjc.A.dylib)
==43059==    by 0x7FFF5FC01DE0: dyld::notifySingle(dyld_image_states, ImageLoader const*) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC0F6B9: ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC0F552: ImageLoader::processInitializers(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC0F580: ImageLoader::processInitializers(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC0F7C2: ImageLoader::runInitializers(ImageLoader::LinkContext const&, ImageLoader::InitializerTimingList&) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC020AA: dyld::initializeMainExecutable() (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC05D46: dyld::_main(macho_header const*, unsigned long, int, char const**, char const**, char const**, unsigned long*) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC01275: dyldbootstrap::start(macho_header const*, int, char const**, long, macho_header const*, unsigned long*) (in /usr/lib/dyld)
==43059==    by 0x7FFF5FC01035: _dyld_start (in /usr/lib/dyld)
==43059== 
==43059== LEAK SUMMARY:
==43059==    definitely lost: 4,416 bytes in 4 blocks
==43059==    indirectly lost: 2,288 bytes in 6 blocks
==43059==      possibly lost: 7,096 bytes in 68 blocks
==43059==    still reachable: 8,445 bytes in 109 blocks
==43059==         suppressed: 0 bytes in 0 blocks
==43059== Reachable blocks (those to which a pointer was found) are not shown.
==43059== To see them, rerun with: --leak-check=full --show-leak-kinds=all
==43059== 
==43059== For counts of detected and suppressed errors, rerun with: -v
==43059== ERROR SUMMARY: 17 errors from 17 contexts (suppressed: 0 from 0)

当您查看这些堆栈跟踪时，您会发现其中没有main 的条目。这表明问题不在您的代码中；它在系统代码中。因此，您再次使用 --gen-suppressions=all 重新运行 Valgrind，并获得如下输出：

$ valgrind --gen-suppressions=all --num-callers=100 --leak-check=full ./leaks
==43060== Memcheck, a memory error detector
==43060== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.
==43060== Using Valgrind-3.11.0.SVN and LibVEX; rerun with -h for copyright info
==43060== Command: ./leaks
==43060== 
--43060-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option
--43060-- UNKNOWN fcntl 97!
--43060-- UNKNOWN fcntl 97! (repeated 2 times)
--43060-- UNKNOWN fcntl 97! (repeated 4 times)
--43060-- UNKNOWN fcntl 97! (repeated 8 times)
--43060-- UNKNOWN fcntl 97! (repeated 16 times)
--43060-- UNKNOWN fcntl 97! (repeated 32 times)
--43060-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option (repeated 2 times)
--43060-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option (repeated 4 times)
--43060-- UNKNOWN task message [id 3406, to mach_task_self(), reply 0x60f]
--43060-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option (repeated 8 times)
--43060-- UNKNOWN host message [id 412, to mach_host_self(), reply 0x60f]
--43060-- UNKNOWN host message [id 222, to mach_host_self(), reply 0x60f]
--43060-- UNKNOWN task message [id 3410, to mach_task_self(), reply 0x60f]
==43060== 
==43060== HEAP SUMMARY:
==43060==     in use at exit: 22,245 bytes in 187 blocks
==43060==   total heap usage: 263 allocs, 76 frees, 28,341 bytes allocated
==43060== 
==43060== 24 bytes in 1 blocks are possibly lost in loss record 9 of 62
==43060==    at 0x100006355: malloc_zone_calloc (vg_replace_malloc.c:632)
==43060==    by 0x1004FE4B1: NXHashInsert (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x1004FE1BE: NXCreateHashTableFromZone (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x1004FE053: NXCreateHashTable (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x1004FD037: _read_images (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x1004FBB4D: map_images_nolock (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x1004FB538: map_2_images (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x7FFF5FC047CF: dyld::notifyBatchPartial(dyld_image_states, bool, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC04516: dyld::registerImageStateBatchChangeHandler(dyld_image_states, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==43060==    by 0x10016689D: dyld_register_image_state_change_handler (in /usr/lib/system/libdyld.dylib)
==43060==    by 0x1004FB07A: _objc_init (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x10010EC4B: _os_object_init (in /usr/lib/system/libdispatch.dylib)
==43060==    by 0x10010EC37: libdispatch_init (in /usr/lib/system/libdispatch.dylib)
==43060==    by 0x100010A01: libSystem_initializer (in /usr/lib/libSystem.B.dylib)
==43060==    by 0x7FFF5FC12F1A: ImageLoaderMachO::doModInitFunctions(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC13093: ImageLoaderMachO::doInitialization(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC0F6CC: ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC0F661: ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC0F552: ImageLoader::processInitializers(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC0F7C2: ImageLoader::runInitializers(ImageLoader::LinkContext const&, ImageLoader::InitializerTimingList&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC020AA: dyld::initializeMainExecutable() (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC05D46: dyld::_main(macho_header const*, unsigned long, int, char const**, char const**, char const**, unsigned long*) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC01275: dyldbootstrap::start(macho_header const*, int, char const**, long, macho_header const*, unsigned long*) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC01035: _dyld_start (in /usr/lib/dyld)
==43060== 
{
   <insert_a_suppression_name_here>
   Memcheck:Leak
   match-leak-kinds: possible
   fun:malloc_zone_calloc
   fun:NXHashInsert
   fun:NXCreateHashTableFromZone
   fun:NXCreateHashTable
   fun:_read_images
   fun:map_images_nolock
   fun:map_2_images
   fun:_ZN4dyldL18notifyBatchPartialE17dyld_image_statesbPFPKcS0_jPK15dyld_image_infoE
   fun:_ZN4dyld36registerImageStateBatchChangeHandlerE17dyld_image_statesPFPKcS0_jPK15dyld_image_infoE
   fun:dyld_register_image_state_change_handler
   fun:_objc_init
   fun:_os_object_init
   fun:libdispatch_init
   fun:libSystem_initializer
   fun:_ZN16ImageLoaderMachO18doModInitFunctionsERKN11ImageLoader11LinkContextE
   fun:_ZN16ImageLoaderMachO16doInitializationERKN11ImageLoader11LinkContextE
   fun:_ZN11ImageLoader23recursiveInitializationERKNS_11LinkContextEjRNS_21InitializerTimingListERNS_15UninitedUpwardsE
   fun:_ZN11ImageLoader23recursiveInitializationERKNS_11LinkContextEjRNS_21InitializerTimingListERNS_15UninitedUpwardsE
   fun:_ZN11ImageLoader19processInitializersERKNS_11LinkContextEjRNS_21InitializerTimingListERNS_15UninitedUpwardsE
   fun:_ZN11ImageLoader15runInitializersERKNS_11LinkContextERNS_21InitializerTimingListE
   fun:_ZN4dyld24initializeMainExecutableEv
   fun:_ZN4dyld5_mainEPK12macho_headermiPPKcS5_S5_Pm
   fun:_ZN13dyldbootstrap5startEPK12macho_headeriPPKclS2_Pm
   fun:_dyld_start
}
==43060== 24 bytes in 1 blocks are possibly lost in loss record 10 of 62
==43060==    at 0x100006355: malloc_zone_calloc (vg_replace_malloc.c:632)
==43060==    by 0x1004FE4B1: NXHashInsert (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x100500223: realizeClass(objc_class*) (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x1004FD90C: _read_images (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x1004FBB4D: map_images_nolock (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x1004FB538: map_2_images (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x7FFF5FC047CF: dyld::notifyBatchPartial(dyld_image_states, bool, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC04516: dyld::registerImageStateBatchChangeHandler(dyld_image_states, char const* (*)(dyld_image_states, unsigned int, dyld_image_info const*)) (in /usr/lib/dyld)
==43060==    by 0x10016689D: dyld_register_image_state_change_handler (in /usr/lib/system/libdyld.dylib)
==43060==    by 0x1004FB07A: _objc_init (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x10010EC4B: _os_object_init (in /usr/lib/system/libdispatch.dylib)
==43060==    by 0x10010EC37: libdispatch_init (in /usr/lib/system/libdispatch.dylib)
==43060==    by 0x100010A01: libSystem_initializer (in /usr/lib/libSystem.B.dylib)
==43060==    by 0x7FFF5FC12F1A: ImageLoaderMachO::doModInitFunctions(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC13093: ImageLoaderMachO::doInitialization(ImageLoader::LinkContext const&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC0F6CC: ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC0F661: ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC0F552: ImageLoader::processInitializers(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC0F7C2: ImageLoader::runInitializers(ImageLoader::LinkContext const&, ImageLoader::InitializerTimingList&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC020AA: dyld::initializeMainExecutable() (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC05D46: dyld::_main(macho_header const*, unsigned long, int, char const**, char const**, char const**, unsigned long*) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC01275: dyldbootstrap::start(macho_header const*, int, char const**, long, macho_header const*, unsigned long*) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC01035: _dyld_start (in /usr/lib/dyld)
==43060== 

…lots of material omitted again…

==43060== 4,096 bytes in 1 blocks are definitely lost in loss record 62 of 62
==43060==    at 0x100007110: malloc_zone_memalign (vg_replace_malloc.c:769)
==43060==    by 0x100504D71: (anonymous namespace)::AutoreleasePoolPage::autoreleaseNoPage(objc_object*) (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x100504CF5: objc_autoreleasePoolPush (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x100504998: call_load_methods (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x100501B9D: load_images (in /usr/lib/libobjc.A.dylib)
==43060==    by 0x7FFF5FC01DE0: dyld::notifySingle(dyld_image_states, ImageLoader const*) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC0F6B9: ImageLoader::recursiveInitialization(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC0F552: ImageLoader::processInitializers(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC0F580: ImageLoader::processInitializers(ImageLoader::LinkContext const&, unsigned int, ImageLoader::InitializerTimingList&, ImageLoader::UninitedUpwards&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC0F7C2: ImageLoader::runInitializers(ImageLoader::LinkContext const&, ImageLoader::InitializerTimingList&) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC020AA: dyld::initializeMainExecutable() (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC05D46: dyld::_main(macho_header const*, unsigned long, int, char const**, char const**, char const**, unsigned long*) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC01275: dyldbootstrap::start(macho_header const*, int, char const**, long, macho_header const*, unsigned long*) (in /usr/lib/dyld)
==43060==    by 0x7FFF5FC01035: _dyld_start (in /usr/lib/dyld)
==43060== 
{
   <insert_a_suppression_name_here>
   Memcheck:Leak
   match-leak-kinds: definite
   fun:malloc_zone_memalign
   fun:_ZN12_GLOBAL__N_119AutoreleasePoolPage17autoreleaseNoPageEP11objc_object
   fun:objc_autoreleasePoolPush
   fun:call_load_methods
   fun:load_images
   fun:_ZN4dyldL12notifySingleE17dyld_image_statesPK11ImageLoader
   fun:_ZN11ImageLoader23recursiveInitializationERKNS_11LinkContextEjRNS_21InitializerTimingListERNS_15UninitedUpwardsE
   fun:_ZN11ImageLoader19processInitializersERKNS_11LinkContextEjRNS_21InitializerTimingListERNS_15UninitedUpwardsE
   fun:_ZN11ImageLoader19processInitializersERKNS_11LinkContextEjRNS_21InitializerTimingListERNS_15UninitedUpwardsE
   fun:_ZN11ImageLoader15runInitializersERKNS_11LinkContextERNS_21InitializerTimingListE
   fun:_ZN4dyld24initializeMainExecutableEv
   fun:_ZN4dyld5_mainEPK12macho_headermiPPKcS5_S5_Pm
   fun:_ZN13dyldbootstrap5startEPK12macho_headeriPPKclS2_Pm
   fun:_dyld_start
}
==43060== LEAK SUMMARY:
==43060==    definitely lost: 4,416 bytes in 4 blocks
==43060==    indirectly lost: 2,288 bytes in 6 blocks
==43060==      possibly lost: 7,096 bytes in 68 blocks
==43060==    still reachable: 8,445 bytes in 109 blocks
==43060==         suppressed: 0 bytes in 0 blocks
==43060== Reachable blocks (those to which a pointer was found) are not shown.
==43060== To see them, rerun with: --leak-check=full --show-leak-kinds=all
==43060== 
==43060== For counts of detected and suppressed errors, rerun with: -v
==43060== ERROR SUMMARY: 17 errors from 17 contexts (suppressed: 0 from 0)
$

然后你将抑制收集到一个文件中，用更有用的东西替换<insert_a_suppression_name_here>。比如我之前创建了一个入口：

{
   Mac-OS-X-El-Capitan-System-Leak.019
   Memcheck:Leak
   match-leak-kinds: definite
   fun:malloc_zone_memalign
   fun:_ZN12_GLOBAL__N_119AutoreleasePoolPage17autoreleaseNoPageEP11objc_object
   fun:objc_autoreleasePoolPush
   fun:call_load_methods
   fun:load_images
   fun:_ZN4dyldL12notifySingleE17dyld_image_statesPK11ImageLoader
   fun:_ZN11ImageLoader23recursiveInitializationERKNS_11LinkContextEjRNS_21InitializerTimingListERNS_15UninitedUpwardsE
   fun:_ZN11ImageLoader19processInitializersERKNS_11LinkContextEjRNS_21InitializerTimingListERNS_15UninitedUpwardsE
   fun:_ZN11ImageLoader19processInitializersERKNS_11LinkContextEjRNS_21InitializerTimingListERNS_15UninitedUpwardsE
   fun:_ZN11ImageLoader15runInitializersERKNS_11LinkContextERNS_21InitializerTimingListE
   fun:_ZN4dyld24initializeMainExecutableEv
   fun:_ZN4dyld5_mainEPK12macho_headermiPPKcS5_S5_Pm
}

保存在文件suppressions 中。如果我使用以前的抑制文件（我恰好与leaks 代码位于同一目录中）运行代码，我会得到：

$ valgrind --suppressions=suppressions --leak-check=full --num-callers=100 ./leaks
==43063== Memcheck, a memory error detector
==43063== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.
==43063== Using Valgrind-3.11.0.SVN and LibVEX; rerun with -h for copyright info
==43063== Command: ./leaks
==43063== 
--43063-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option
--43063-- UNKNOWN fcntl 97!
--43063-- UNKNOWN fcntl 97! (repeated 2 times)
--43063-- UNKNOWN fcntl 97! (repeated 4 times)
--43063-- UNKNOWN fcntl 97! (repeated 8 times)
--43063-- UNKNOWN fcntl 97! (repeated 16 times)
--43063-- UNKNOWN fcntl 97! (repeated 32 times)
--43063-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option (repeated 2 times)
--43063-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option (repeated 4 times)
--43063-- UNKNOWN task message [id 3406, to mach_task_self(), reply 0x60f]
--43063-- UNKNOWN mach_msg unhandled MACH_SEND_TRAILER option (repeated 8 times)
--43063-- UNKNOWN host message [id 412, to mach_host_self(), reply 0x60f]
--43063-- UNKNOWN host message [id 222, to mach_host_self(), reply 0x60f]
--43063-- UNKNOWN task message [id 3410, to mach_task_self(), reply 0x60f]
==43063== 
==43063== HEAP SUMMARY:
==43063==     in use at exit: 22,245 bytes in 187 blocks
==43063==   total heap usage: 263 allocs, 76 frees, 28,341 bytes allocated
==43063== 
==43063== LEAK SUMMARY:
==43063==    definitely lost: 0 bytes in 0 blocks
==43063==    indirectly lost: 2,288 bytes in 6 blocks
==43063==      possibly lost: 0 bytes in 0 blocks
==43063==    still reachable: 8,445 bytes in 109 blocks
==43063==         suppressed: 11,512 bytes in 72 blocks
==43063== Reachable blocks (those to which a pointer was found) are not shown.
==43063== To see them, rerun with: --leak-check=full --show-leak-kinds=all
==43063== 
==43063== For counts of detected and suppressed errors, rerun with: -v
==43063== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 17 from 17)
$

你可以看到我需要做一些工作来抑制一些分配，但没有任何泄漏声称。

这也大致是您需要做的。您应该能够与 Valgrind 一起安装抑制功能，这样您就不必每次都指定 --suppressions=suppressions。

（我不得不修剪输出以适应 SO 的 30,000 个字符限制。）

【讨论】：