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Valgrind是一款用于内存调试、内存泄漏检测以及性能分析的神器，能够帮助我们快速定位到程序的内存问题，比如内存泄漏导致的 段错误 (核心已转储)

包含以下工具：

• Memcheck：检查程序中的内存问题，如泄漏、越界、非法指针等
• Callgrind：主要用来检查程序中函数调用过程中出现的问题。
• Cachegrind：分析CPU的cache命中率、丢失率，用于进行代码优化。
• Helgrind：主要用来检查多线程程序中出现的竞争问题。
• Massif：主要用来检查程序中堆栈使用中出现的问题。
• Extension：可利用core提供的功能，自己编写特定的内存调试工具

使用语法如下：

 valgrind [options]  ./prog_fileusage: valgrind [options] prog-and-argstool-selection option, with default in [ ]:--tool=<name>             use the Valgrind tool named <name> [memcheck]basic user options for all Valgrind tools, with defaults in [ ]:-h --help                 show this message--help-debug              show this message, plus debugging options--version                 show version-q --quiet                run silently; only print error msgs-v --verbose              be more verbose -- show misc extra info--trace-children=no|yes   Valgrind-ise child processes (follow execve)? [no]--trace-children-skip=patt1,patt2,...    specifies a list of executablesthat --trace-children=yes should not trace into--trace-children-skip-by-arg=patt1,patt2,...   same as --trace-children-skip=but check the argv[] entries for children, ratherthan the exe name, to make a follow/no-follow decision--child-silent-after-fork=no|yes omit child output between fork & exec? [no]--vgdb=no|yes|full        activate gdbserver? [yes]full is slower but provides precise watchpoint/step--vgdb-error=<number>     invoke gdbserver after <number> errors [999999999]to get started quickly, use --vgdb-error=0and follow the on-screen directions--vgdb-stop-at=event1,event2,... invoke gdbserver for given events [none]where event is one of:startup exit valgrindabexit all none--track-fds=no|yes        track open file descriptors? [no]--time-stamp=no|yes       add timestamps to log messages? [no]--log-fd=<number>         log messages to file descriptor [2=stderr]--log-file=<file>         log messages to <file>--log-socket=ipaddr:port  log messages to socket ipaddr:portuser options for Valgrind tools that report errors:--xml=yes                 emit error output in XML (some tools only)--xml-fd=<number>         XML output to file descriptor--xml-file=<file>         XML output to <file>--xml-socket=ipaddr:port  XML output to socket ipaddr:port--xml-user-comment=STR    copy STR verbatim into XML output--demangle=no|yes         automatically demangle C++ names? [yes]--num-callers=<number>    show <number> callers in stack traces [12]--error-limit=no|yes      stop showing new errors if too many? [yes]--error-exitcode=<number> exit code to return if errors found [0=disable]--error-markers=<begin>,<end> add lines with begin/end markers before/aftereach error output in plain text mode [none]--show-below-main=no|yes  continue stack traces below main() [no]--default-suppressions=yes|noload default suppressions [yes]--suppressions=<filename> suppress errors described in <filename>--gen-suppressions=no|yes|all    print suppressions for errors? [no]--input-fd=<number>       file descriptor for input [0=stdin]--dsymutil=no|yes         run dsymutil on Mac OS X when helpful? [yes]--max-stackframe=<number> assume stack switch for SP changes largerthan <number> bytes [2000000]--main-stacksize=<number> set size of main thread's stack (in bytes)[min(max(current 'ulimit' value,1MB),16MB)]user options for Valgrind tools that replace malloc:--alignment=<number>      set minimum alignment of heap allocations [16]--redzone-size=<number>   set minimum size of redzones added before/afterheap blocks (in bytes). [16]--xtree-memory=none|allocs|full   profile heap memory in an xtree [none]and produces a report at the end of the executionnone: no profiling, allocs: current allocatedsize/blocks, full: profile current and cumulativeallocated size/blocks and freed size/blocks.--xtree-memory-file=<file>   xtree memory report file [xtmemory.kcg.%p]uncommon user options for all Valgrind tools:--fullpath-after=         (with nothing after the '=')show full source paths in call stacks--fullpath-after=string   like --fullpath-after=, but only show thepart of the path after 'string'.  Allows removalof path prefixes.  Use this flag multiple timesto specify a set of prefixes to remove.--extra-debuginfo-path=path    absolute path to search for additionaldebug symbols, in addition to existing defaultwell known search paths.--debuginfo-server=ipaddr:port    also query this server(valgrind-di-server) for debug symbols--allow-mismatched-debuginfo=no|yes  [no]for the above two flags only, accept debuginfoobjects that don't "match" the main object--smc-check=none|stack|all|all-non-file [all-non-file]checks for self-modifying code: none, only forcode found in stacks, for all code, or for allcode except that from file-backed mappings--read-inline-info=yes|no read debug info about inlined function callsand use it to do better stack traces.  [yes]on Linux/Android/Solaris for Memcheck/Helgrind/DRDonly.  [no] for all other tools and platforms.--read-var-info=yes|no    read debug info on stack and global variablesand use it to print better error messages intools that make use of it (Memcheck, Helgrind,DRD) [no]--vgdb-poll=<number>      gdbserver poll max every <number> basic blocks [5000] --vgdb-shadow-registers=no|yes   let gdb see the shadow registers [no]--vgdb-prefix=<prefix>    prefix for vgdb FIFOs [/tmp/vgdb-pipe]--run-libc-freeres=no|yes free up glibc memory at exit on Linux? [yes]--run-cxx-freeres=no|yes  free up libstdc++ memory at exit on Linuxand Solaris? [yes]--sim-hints=hint1,hint2,...  activate unusual sim behaviours [none] where hint is one of:lax-ioctls lax-doors fuse-compatible enable-outerno-inner-prefix no-nptl-pthread-stackcache fallback-llsc none--fair-sched=no|yes|try   schedule threads fairly on multicore systems [no]--kernel-variant=variant1,variant2,...handle non-standard kernel variants [none]where variant is one of:bproc android-no-hw-tlsandroid-gpu-sgx5xx android-gpu-adreno3xx none--merge-recursive-frames=<number>  merge frames between identicalprogram counters in max <number> frames) [0]--num-transtab-sectors=<number> size of translated code cache [32]more sectors may increase performance, but use more memory.--avg-transtab-entry-size=<number> avg size in bytes of a translatedbasic block [0, meaning use tool provided default]--aspace-minaddr=0xPP     avoid mapping memory below 0xPP [guessed]--valgrind-stacksize=<number> size of valgrind (host) thread's stack(in bytes) [1048576]--show-emwarns=no|yes     show warnings about emulation limits? [no]--require-text-symbol=:sonamepattern:symbolpattern    abort run if thestated shared object doesn't have the statedtext symbol.  Patterns can contain ? and *.--soname-synonyms=syn1=pattern1,syn2=pattern2,... synonym sonamespecify patterns for function wrapping or replacement.To use a non-libc malloc library that isin the main exe:  --soname-synonyms=somalloc=NONEin libxyzzy.so:   --soname-synonyms=somalloc=libxyzzy.so--sigill-diagnostics=yes|no  warn about illegal instructions? [yes]--unw-stack-scan-thresh=<number>   Enable stack-scan unwind if fewerthan <number> good frames found  [0, meaning "disabled"]NOTE: stack scanning is only available on arm-linux.--unw-stack-scan-frames=<number>   Max number of frames that can berecovered by stack scanning [5]--resync-filter=no|yes|verbose [yes on MacOS, no on other OSes]attempt to avoid expensive address-space-resync operations--max-threads=<number>    maximum number of threads that valgrind canhandle [500]user options for Memcheck:--leak-check=no|summary|full     search for memory leaks at exit?  [summary]--leak-resolution=low|med|high   differentiation of leak stack traces [high]--show-leak-kinds=kind1,kind2,.. which leak kinds to show?[definite,possible]--errors-for-leak-kinds=kind1,kind2,..  which leak kinds are errors?[definite,possible]where kind is one of:definite indirect possible reachable all none--leak-check-heuristics=heur1,heur2,... which heuristics to use forimproving leak search false positive [all]where heur is one of:stdstring length64 newarray multipleinheritance all none--show-reachable=yes             same as --show-leak-kinds=all--show-reachable=no --show-possibly-lost=yessame as --show-leak-kinds=definite,possible--show-reachable=no --show-possibly-lost=nosame as --show-leak-kinds=definite--xtree-leak=no|yes              output leak result in xtree format? [no]--xtree-leak-file=<file>         xtree leak report file [xtleak.kcg.%p]--undef-value-errors=no|yes      check for undefined value errors [yes]--track-origins=no|yes           show origins of undefined values? [no]--partial-loads-ok=no|yes        too hard to explain here; see manual [yes]--expensive-definedness-checks=no|yesUse extra-precise definedness tracking [no]--freelist-vol=<number>          volume of freed blocks queue     [20000000]--freelist-big-blocks=<number>   releases first blocks with size>= [1000000]--workaround-gcc296-bugs=no|yes  self explanatory [no].  Deprecated.Use --ignore-range-below-sp instead.--ignore-ranges=0xPP-0xQQ[,0xRR-0xSS]   assume given addresses are OK--ignore-range-below-sp=<number>-<number>  do not report errors foraccesses at the given offsets below SP--malloc-fill=<hexnumber>        fill malloc'd areas with given value--free-fill=<hexnumber>          fill free'd areas with given value--keep-stacktraces=alloc|free|alloc-and-free|alloc-then-free|nonestack trace(s) to keep for malloc'd/free'd areas       [alloc-and-free]--show-mismatched-frees=no|yes   show frees that don't match the allocator? [yes]

博主最常用的是内存诊断工具，使用方法如下：

valgrid --tool=memcheck ./test_file

注意： 编译时添加-g选项，使用memcheck检查时的错误信息可精确到行。