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请教内存释放，怕大牛们看不到，令发一帖吧

2008/5/28镜像同步5 回复

请教达人解释下：（1）下面程序没有发现内存泄露，请问其中的"==2885== Mismatched free() / delete / delete "是什么意思？是说编译器自己发现new [] 和 delete mismatched? 然后自己进行了new[] 和delete []匹配？ [root@hotter test]# cat mem1.c #include <iostream> using namespace std; int main() { int * a = new int[10]; delete a; return 0; } [root@hotter test]# g++ -o mem1 mem1.c [root@hotter test]# valgrind --tool=memcheck ./mem1 ==2885== Memcheck, a memory error detector. ==2885== Copyright (C) 2002-2006, and GNU GPL'd, by Julian Seward et al. ==2885== Using LibVEX rev 1658, a library for dynamic binary translation. ==2885== Copyright (C) 2004-2006, and GNU GPL'd, by OpenWorks LLP. ==2885== Using valgrind-3.2.1, a dynamic binary instrumentation framework. ==2885== Copyright (C) 2000-2006, and GNU GPL'd, by Julian Seward et al. ==2885== For more details, rerun with: -v ==2885== ==2885== Mismatched free() / delete / delete [] ==2885== at 0x4004D31: operator delete(void*) (vg_replace_malloc.c:244) ==2885== by 0x80485F0: main (in /root/test/mem1) ==2885== Address 0x401F028 is 0 bytes inside a block of size 40 alloc'd ==2885== at 0x4005835: operator new[](unsigned) (vg_replace_malloc.c:195) ==2885== by 0x80485E2: main (in /root/test/mem1) ==2885== ==2885== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 15 from 1) ==2885== malloc/free: in use at exit: 0 bytes in 0 blocks. ==2885== malloc/free: 1 allocs, 1 frees, 40 bytes allocated. ==2885== For counts of detected errors, rerun with: -v ==2885== All heap blocks were freed -- no leaks are possible. （2）但是下面这个程序为什么结果很不一样呢，结果泄露了124个bytes 10*12+4 = 124(传说中的标识分配空间的4个字节也被泄露了?) [root@hotter test]# cat mem3.c #pragma /* Edited by zhaotong */ #include <iostream> using std::cout; using std::endl; class A { public: A():n(2){cout<<"Call default constructor of A"<<endl;} explicit A(int k):n(2){i = k; cout<<"Call constructor of A: one parameter"<<endl;} inline virtual void fun1(){cout<<"fun1 of A: void"<<endl;} void fun2(int t ){cout<<"fun2 of A: int"<<endl;} void fun2(int t) const {cout<<"fun2 of A: const"<<endl;} virtual ~A(){cout<<"Call destructor of A"<<endl;} protected: int i; private: static int k; const static int m = 2; const int n; }; int A::k = 0; int main() { cout<<"sizeof A = "<<sizeof(A)<<endl; A * p = new A[10]; delete p; return 0; } [root@hotter test]# g++ -o mem3 mem3.c [root@hotter test]# valgrind --tool=memcheck ./mem3 ==3005== Memcheck, a memory error detector. ==3005== Copyright (C) 2002-2006, and GNU GPL'd, by Julian Seward et al. ==3005== Using LibVEX rev 1658, a library for dynamic binary translation. ==3005== Copyright (C) 2004-2006, and GNU GPL'd, by OpenWorks LLP. ==3005== Using valgrind-3.2.1, a dynamic binary instrumentation framework. ==3005== Copyright (C) 2000-2006, and GNU GPL'd, by Julian Seward et al. ==3005== For more details, rerun with: -v ==3005== sizeof A = 12 Call default constructor of A Call default constructor of A Call default constructor of A Call default constructor of A Call default constructor of A Call default constructor of A Call default constructor of A Call default constructor of A Call default constructor of A Call default constructor of A Call destructor of A ==3005== Invalid free() / delete / delete[] ==3005== at 0x4004D31: operator delete(void*) (vg_replace_malloc.c:244) ==3005== by 0x80489DD: A::~A() (in /root/test/mem3) ==3005== by 0x8048919: main (in /root/test/mem3) ==3005== Address 0x401F02C is 4 bytes inside a block of size 124 alloc'd ==3005== at 0x4005835: operator new[](unsigned) (vg_replace_malloc.c:195) ==3005== by 0x8048847: main (in /root/test/mem3) ==3005== ==3005== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 15 from 1) ==3005== malloc/free: in use at exit: 124 bytes in 1 blocks. ==3005== malloc/free: 1 allocs, 1 frees, 124 bytes allocated. ==3005== For counts of detected errors, rerun with: -v ==3005== searching for pointers to 1 not-freed blocks. ==3005== checked 88,380 bytes. ==3005== ==3005== LEAK SUMMARY: ==3005== definitely lost: 124 bytes in 1 blocks. ==3005== possibly lost: 0 bytes in 0 blocks. ==3005== still reachable: 0 bytes in 0 blocks. ==3005== suppressed: 0 bytes in 0 blocks. ==3005== Use --leak-check=full to see details of leaked memory. (3) 大牛们能真正权威解释下上面class A中的 inline virtual void fun1(){cout<<"fun1 of A: void"<<endl;} 在多态时的内联展开和虚函数指针到底冲突是怎么解决的吗？

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