valgrind 的一个小缺陷
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valgrind 的一个小缺陷
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valgrind 在項目中， 通常被用來做內存泄露的檢查， 性能分析。
近期在使用valgrind做內存泄露， 忽略了此處testcode中的泄露提醒， 結果將代碼提交上去后， 發現還是有內存的泄露， 被同事“嘲笑”了一番。
寫了一小段代碼， 來表述這個問題
?
class A
{
public:
? A(size_t s)
{
m_pdata = new int[s];
}?
private:
int *m_pdata;?
} ;
?nt main()
{A *pa = new A(5);return 0;}?
/*****************************************************/
可以看出， 內存泄露的地方有兩處， 一個出 main中， 一處是?class A 的構造函數中。?
而再看看valgrind的提示信息[tianduo@search041144.sqa.cm4 c++]$ valgrind --leak-check=yes ./a.out ?==4049== Memcheck, a memory error detector.==4049== Copyright (C) 2002-2006, and GNU GPL'd, by Julian Seward et al.==4049== Using LibVEX rev 1658, a library for dynamic binary translation.==4049== Copyright (C) 2004-2006, and GNU GPL'd, by OpenWorks LLP.==4049== Using valgrind-3.2.1, a dynamic binary instrumentation framework.==4049== Copyright (C) 2000-2006, and GNU GPL'd, by Julian Seward et al.==4049== For more details, rerun with: -v==4049==?==4049==?==4049== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 5 from 1)==4049== malloc/free: in use at exit: 28 bytes in 2 blocks.==4049== malloc/free: 2 allocs, 0 frees, 28 bytes allocated.==4049== For counts of detected errors, rerun with: -v==4049== searching for pointers to 2 not-freed blocks.==4049== checked 163,288 bytes.==4049==?==4049== 28 (8 direct, 20 indirect) bytes in 1 blocks are definitely lost in loss record 1 of 2==4049== ? ?at 0x4A06019: operator new(unsigned long) (vg_replace_malloc.c:167)==4049== ? ?by 0x4006AA: main (memory.cpp:14)==4049==?==4049== LEAK SUMMARY:==4049== ? ?definitely lost: 8 bytes in 1 blocks.==4049== ? ?indirectly lost: 20 bytes in 1 blocks.==4049== ? ? ?possibly lost: 0 bytes in 0 blocks.==4049== ? ?still reachable: 0 bytes in 0 blocks.==4049== ? ? ? ? suppressed: 0 bytes in 0 blocks.==4049== Reachable blocks (those to which a pointer was found) are not shown.==4049== To see them, rerun with: --show-reachable=yes?
?粗略一看， 只有 ?main函數的14行， 如果在測試的時候， 認為忽略這一行， 那就遺漏了 class A中的泄露點。
??
轉載于:https://www.cnblogs.com/nosaferyao/archive/2011/12/31/2308781.html
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