valgrind试用（1）

valgrind试用（1）

安装程序
sudo apt-get install valgrind

编辑测试程序

gedit test.cpp

#include <string.h>
#include <stdlib.h>


int main(int argc, char *argv[])
{
    char *ptr;

    ptr = (char*) malloc(10);
    strcpy(ptr, "01234567890");

    return 0;
}

编译运行
cutepig@ubuntu:~/testValgrind$ g++ -g -o test test.cpp
cutepig@ubuntu:~/testValgrind$ valgrind --tool=memcheck --leak-check=yes ./test
==13038== Memcheck, a memory error detector
==13038== Copyright (C) 2002-2009, and GNU GPL'd, by Julian Seward et al.
==13038== Using Valgrind-3.5.0-Debian and LibVEX; rerun with -h for copyright info
==13038== Command: ./test
==13038==
==13038== Invalid write of size 1
==13038==    at 0x4026195: memcpy (mc_replace_strmem.c:482)
==13038==    by 0x8048538: main (test.cpp:10)
==13038==  Address 0x42b6032 is 0 bytes after a block of size 10 alloc'd
==13038==    at 0x4024C1C: malloc (vg_replace_malloc.c:195)
==13038==    by 0x8048518: main (test.cpp:9)
==13038==
==13038== Invalid write of size 1
==13038==    at 0x402619E: memcpy (mc_replace_strmem.c:482)
==13038==    by 0x8048538: main (test.cpp:10)
==13038==  Address 0x42b6033 is 1 bytes after a block of size 10 alloc'd
==13038==    at 0x4024C1C: malloc (vg_replace_malloc.c:195)
==13038==    by 0x8048518: main (test.cpp:9)
==13038==
==13038==
==13038== HEAP SUMMARY:
==13038==     in use at exit: 10 bytes in 1 blocks
==13038==   total heap usage: 1 allocs, 0 frees, 10 bytes allocated
==13038==
==13038== 10 bytes in 1 blocks are definitely lost in loss record 1 of 1
==13038==    at 0x4024C1C: malloc (vg_replace_malloc.c:195)
==13038==    by 0x8048518: main (test.cpp:9)
==13038==
==13038== LEAK SUMMARY:
==13038==    definitely lost: 10 bytes in 1 blocks
==13038==    indirectly lost: 0 bytes in 0 blocks
==13038==      possibly lost: 0 bytes in 0 blocks
==13038==    still reachable: 0 bytes in 0 blocks
==13038==         suppressed: 0 bytes in 0 blocks
==13038==
==13038== For counts of detected and suppressed errors, rerun with: -v
==13038== ERROR SUMMARY: 3 errors from 3 contexts (suppressed: 18 from 7)

检查到越界，位于main (test.cpp:10)，泄露，位于main (test.cpp:9)

再写一个没问题的程序
cutepig@ubuntu:~/testValgrind$ gedit test2.cpp

#include <string.h>
#include <stdlib.h>


int main(int argc, char *argv[])
{
    char *ptr;

    ptr = (char*) malloc(100);
    strcpy(ptr, "01234567890");
    free(ptr);

    return 0;
}

cutepig@ubuntu:~/testValgrind$ g++ test2.cpp
cutepig@ubuntu:~/testValgrind$ valgrind --tool=memcheck --leak-check=yes ./a.out
==12949== Memcheck, a memory error detector
==12949== Copyright (C) 2002-2009, and GNU GPL'd, by Julian Seward et al.
==12949== Using Valgrind-3.5.0-Debian and LibVEX; rerun with -h for copyright info
==12949== Command: ./a.out
==12949==
==12949==
==12949== HEAP SUMMARY:
==12949==     in use at exit: 0 bytes in 0 blocks
==12949==   total heap usage: 1 allocs, 1 frees, 100 bytes allocated
==12949==
==12949== All heap blocks were freed -- no leaks are possible
==12949==
==12949== For counts of detected and suppressed errors, rerun with: -v
==12949== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 18 from 7)

ok，没有内存问题
http://www.cnblogs.com/cutepig/archive/2009/08/02/1537180.html