这是什么意思？
- 在那个类中我没有任何动态分配内存？
这是构造函数类似地导致了泄漏。
class memory :public Moudle{
private:
map<string, Moudle*> oData;
string id;
int size;
int currsize;
bool alive;
public:
memory();
memory(int _i,string _id):Moudle(Memory){
id = _id;
size = _i;
alive = true;
currsize = 0;
}
bool isalive(){ return alive; }
void kill(){ alive = false; }
string getid(){ return id; }
virtual void stop();
void del(string id){ oData.erase(id); }
bool find(string id);
Moudle* getMoudle(string id);
void insertFile(string id, Moudle* file);
virtual string read() { return ""; }
virtual void addElem(int index, string val) {}
bool isfull(){ return (currsize>size || currsize == size); }
string print(int mode);
};
这是valgrind的日志输出： 我使用的是Ubuntu Linux，并在g++ 98中编译。
==25429== Memcheck, a memory error detector
==25429== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.
==25429== Using Valgrind-3.10.0.SVN and LibVEX; rerun with -h for copyright info
==25429== Command: ./prog
==25429== Parent PID: 5070
==25429==
==25429==
==25429== HEAP SUMMARY:
==25429== in use at exit: 546 bytes in 12 blocks
==25429== total heap usage: 85 allocs, 73 frees, 13,062 bytes allocated
==25429==
==25429== 546 (88 direct, 458 indirect) bytes in 1 blocks are definitely lost in loss record 11 of 11
==25429== at 0x4C2B0E0: operator new(unsigned long) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==25429== by 0x402D13: create::DoCommand(std::string*, OS&) (in /home/naor_pc/Desktop/1/prog)
==25429== by 0x40ADC1: operatCreate(std::string) (in /home/naor_pc/Desktop/1/prog)
==25429== by 0x40B856: OS::runShell() (in /home/naor_pc/Desktop/1/prog)
==25429== by 0x406CA8: main (in /home/naor_pc/Desktop/1/prog)
==25429==
==25429== LEAK SUMMARY:
==25429== definitely lost: 88 bytes in 1 blocks
==25429== indirectly lost: 458 bytes in 11 blocks
==25429== possibly lost: 0 bytes in 0 blocks
==25429== still reachable: 0 bytes in 0 blocks
==25429== suppressed: 0 bytes in 0 blocks
==25429==
==25429== For counts of detected and suppressed errors, rerun with: -v
==25429== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 0 from 0)
最简单的例子（提交给 bugs.kde.org：https://bugs.kde.org/show_bug.cgi?id=459047）：
void divide2DDoubleArray(double * &block, double ** &subblockdividers, int noofsubblocks, int subblocksize){
/* The starting address of a block of doubles is used to generate
* pointers to subblocks.
*
* block: memory containing the original block of data
* subblockdividers: array of subblock addresses
* noofsubblocks: specify the number of subblocks produced
* subblocksize: specify the size of the subblocks produced
*
* Design by contract: application should make sure the memory
* in block is allocated and initialized properly.
*/
// Build 2D matrix for cols
subblockdividers=new double *[noofsubblocks];
subblockdividers[0]= block;
for (int i=1; i<noofsubblocks; ++i) {
subblockdividers[i] = &subblockdividers[i-1][subblocksize];
}
}
int main(){
double * testarray = new double[16];
double ** pTestarray;
divide2DDoubleArray(testarray, pTestarray, 4, 4);
delete[] pTestarray;
}
编译时使用的：
g++ -g valgrind_error.cpp -o ve.out
并运行
valgrind --leak-check=yes ./ve.out
产生：
==5775== Memcheck, a memory error detector
==5775== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==5775== Using Valgrind-3.15.0 and LibVEX; rerun with -h for copyright info
==5775== Command: ./ve.out
==5775==
==5775==
==5775== HEAP SUMMARY:
==5775== in use at exit: 128 bytes in 1 blocks
==5775== total heap usage: 3 allocs, 2 frees, 72,864 bytes allocated
==5775==
==5775== 128 bytes in 1 blocks are definitely lost in loss record 1 of 1
==5775== at 0x483C583: operator new[](unsigned long) (in /usr/lib/x86_64-linux-gnu/valgrind/vgpreload_memcheck-amd64-linux.so)
==5775== by 0x109283: main (valgrind_error.cpp:25)
==5775==
==5775== LEAK SUMMARY:
==5775== definitely lost: 128 bytes in 1 blocks
==5775== indirectly lost: 0 bytes in 0 blocks
==5775== possibly lost: 0 bytes in 0 blocks
==5775== still reachable: 0 bytes in 0 blocks
==5775== suppressed: 0 bytes in 0 blocks
==5775==
==5775== For lists of detected and suppressed errors, rerun with: -s
==5775== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 0 from 0)
涉及的代码仅使用指向双精度浮点数和指向双重指针的指针。然而，我们发现与“operator new[]（在/ usr / lib / x86_64-linux-gnu / valgrind / vgpreload_memcheck-amd64-linux.so中）相关的内存泄漏”。这不是来自最小示例。