Memory leak possibly lost

[無名小伙]

#include <iostream>
#include <pthread.h>
#include <vector>
using namespace std;

void* thread_func(void* args)
{
    int * q = new int;
    return 0;
}

int main(int argc,char *argv[])
{
    if(argc!=2)
    {
        cout<<"Run with:"<<argv[0]<<" thread_count"<<endl;
        return -1;
    }
    unsigned int NUM_THREADS= atoi(argv[1]);
    pthread_t tids[NUM_THREADS];
    for(int i = 0; i < NUM_THREADS; ++i)
    {
        int ret = pthread_create(&tids[i], NULL, thread_func, NULL);
        if (ret != 0)
        {
                sleep(2);
           cout << "pthread_create error: error_code=" << ret << endl;
        }
    }
     pthread_exit(NULL);
}

==================
==26418==
==26418== HEAP SUMMARY:
==26418==     in use at exit: 2,920 bytes in 20 blocks
==26418==   total heap usage: 25 allocs, 5 frees, 5,424 bytes allocated
==26418==
==26418== 40 bytes in 10 blocks are definitely lost in loss record 1 of 2
==26418==    at 0x4C2877F: operator new(unsigned long) (vg_replace_malloc.c:298)
==26418==    by 0x400C31: thread_func(void*) (in /leak)
==26418==    by 0x4E35850: start_thread (in /lib64/libpthread-2.12.so)
==26418==    by 0x58D394C: clone (in /lib64/libc-2.12.so)
==26418==
==26418== 2,880 bytes in 10 blocks are possibly lost in loss record 2 of 2
==26418==    at 0x4C266D5: calloc (vg_replace_malloc.c:593)
==26418==    by 0x4011892: _dl_allocate_tls (in /lib64/ld-2.12.so)
==26418==    by 0x4E35068: pthread_create@@GLIBC_2.2.5 (in /lib64/libpthread-2.12.so)
==26418==    by 0x400BA2: main (in /leak)
==26418==    by 0x5809CDC: __libc_start_main (in /lib64/libc-2.12.so)
==26418==    by 0x400998: ??? (in /leak)
==26418==    by 0x7FF000737: ???
==26418==    by 0x1B: ???
==26418==    by 0x1: ???
==26418==    by 0x7FF0009DA: ???
==26418==    by 0x7FF0009E7: ???
==26418==
==26418== LEAK SUMMARY:
==26418==    definitely lost: 40 bytes in 10 blocks
==26418==    indirectly lost: 0 bytes in 0 blocks
==26418==      possibly lost: 2,880 bytes in 10 blocks
==26418==    still reachable: 0 bytes in 0 blocks
==26418==         suppressed: 0 bytes in 0 blocks
==26418==
==26418== For counts of detected and suppressed errors, rerun with: -v
==26418== ERROR SUMMARY: 2 errors from 2 contexts (suppressed: 0 from 0)

这里的possibly lost: 2,880 bytes in 10 blocks 在什么地方？

[赵4老师]

第8行int * q = new int;里面的new对应哪个delete？

[starytx]

int * q = new int; 你函数中new的这个指针都丢失了何时释放？

[無名小伙]

引用 2 楼 starytx 的回复:

int * q = new int; 你函数中new的这个指针都丢失了何时释放？

有个两个提示: 1. definitely lost: 40 bytes in 10 blocks 这个是new的没有释放 2. possibly lost: 2,880 bytes in 10 blocks 这个呢？

[無名小伙]

#include <iostream>
#include <pthread.h>
#include <vector>
using namespace std;

void* thread_func(void* args)
{
    return 0;
}

int main(int argc,char *argv[])
{
    if(argc!=2)
    {
        cout<<"Run with:"<<argv[0]<<" thread_count"<<endl;
        return -1;
    }
    unsigned int NUM_THREADS= atoi(argv[1]);
    pthread_t tids[NUM_THREADS];
    for(int i = 0; i < NUM_THREADS; ++i)
    {
        int ret = pthread_create(&tids[i], NULL, thread_func, NULL);
        if (ret != 0)
        {
                sleep(2);
           cout << "pthread_create error: error_code=" << ret << endl;
        }
    }
     pthread_exit(NULL);
}

==12919== Memcheck, a memory error detector
==12919== Copyright (C) 2002-2012, and GNU GPL'd, by Julian Seward et al.
==12919== Using Valgrind-3.8.0 and LibVEX; rerun with -h for copyright info
==12919== Command: /etc/SU/leak 10
==12919== Parent PID: 20231
==12919== 
==12919== 
==12919== HEAP SUMMARY:
==12919==     in use at exit: 2,880 bytes in 10 blocks
==12919==   total heap usage: 15 allocs, 5 frees, 5,384 bytes allocated
==12919== 
==12919== 2,880 bytes in 10 blocks are possibly lost in loss record 1 of 1
==12919==    at 0x4C266D5: calloc (vg_replace_malloc.c:593)
==12919==    by 0x4011892: _dl_allocate_tls (in /lib64/ld-2.12.so)
==12919==    by 0x4E35068: pthread_create@@GLIBC_2.2.5 (in /lib64/libpthread-2.12.so)
==12919==    by 0x400B62: main (in /PLATsoftware/cs/sn/SU/leak)
==12919==    by 0x5809CDC: __libc_start_main (in /lib64/libc-2.12.so)
==12919==    by 0x400948: ??? (in /PLATsoftware/cs/sn/SU/leak)
==12919==    by 0x7FF000737: ???
==12919==    by 0x1B: ???
==12919==    by 0x1: ???
==12919==    by 0x7FF0009DA: ???
==12919==    by 0x7FF0009E7: ???
==12919== 
==12919== LEAK SUMMARY:
==12919==    definitely lost: 0 bytes in 0 blocks
==12919==    indirectly lost: 0 bytes in 0 blocks
==12919==      possibly lost: 2,880 bytes in 10 blocks
==12919==    still reachable: 0 bytes in 0 blocks
==12919==         suppressed: 0 bytes in 0 blocks
==12919== 
==12919== For counts of detected and suppressed errors, rerun with: -v
==12919== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 0 from 0)

现在应该是清晰的了吧？大神们，请回答？

[赵4老师]

==12919== 2,880 bytes in 10 blocks are possibly lost in loss record 1 of 1 ==12919== at 0x4C266D5: calloc (vg_replace_malloc.c:593) 看看vg_replace_malloc.c的第593行？

[叶之香]

pthread_create导致的内存泄露 http://www.cnblogs.com/bits/archive/2009/12/04/no_join_or_detach_memory_leak.html

[赵4老师]

试试这个看有没有内存泄漏：

#include <iostream>
#include <pthread.h>
#include <vector>
using namespace std;

void* thread_func(void* args)
{
    pthread_exit(NULL);
}

int main(int argc,char *argv[])
{
    if(argc!=2)
    {
        cout<<"Run with:"<<argv[0]<<" thread_count"<<endl;
        return -1;
    }
    unsigned int NUM_THREADS= atoi(argv[1]);
    pthread_t tids[NUM_THREADS];
    for(int i = 0; i < NUM_THREADS; ++i)
    {
        int ret = pthread_create(&tids[i], NULL, thread_func, NULL);
        if (ret != 0)
        {
                sleep(2);
           cout << "pthread_create error: error_code=" << ret << endl;
        }
    }
    return 0;
}