c++ - 自定义分配器的奇怪行为

Question

如果我运行该程序，它将返回 SIGSEGV。如果我对其进行分解和调试，我会看到它在函数 dCAllocator::free() 开始时崩溃。

#include <cstdlib>

class dCAllocator
{
public:
    void * alloc(unsigned long size)
    {
        return malloc(size);
    }
    void free(void * p)
    {
        free(p);
    }
};
int main()
{
    dCAllocator dalloc;
    int * arr = (int*)dalloc.alloc(sizeof(int)*40);
    for (int i=0; i<40; ++i)
        arr[i] = i*2;
    for (int i=0; i<40; ++i)
        cout << arr[i] << ", ";
    cout << endl;
    cout << "END" << endl;
    dalloc.free(arr);  // There is SIGSEGV
    cout << "OF DEALLOCATION" << endl;
    return 0;
}

Answer 1

您的 free() 成员将调用自身，直到用完堆栈空间。您可能打算调用 ::free():

void dCAllocator::free(void* ptr) {
    ::free(ptr);
}