C++ 释放共享库中动态分配的 memory 导致崩溃

Question

I have a shared library mod.so and it has a function getptr to return pointer to a dynamically allocated memory.It also has a function Unload which frees the memory which was allocated. The main program loads this shared library at runtime and gets the pointer from getptr function but when Unload function is called it gives me Segmentation Fault.

main.cpp

    #include <iostream>
#include <dlfcn.h>
using namespace std;
int main()
{
  void* module = dlopen("mod.so",RTLD_LAZY);
  typedef int*(*func)();
  typedef void(*func1)();
  func f = (func)dlsym(module,"getptr");
  func1 b = (func1)dlsym(module,"Unload");
  int* p = f();
  b();
}

mod.cpp

    #include <iostream>
#include <vector>
using namespace std;
vector<int*> allocated;
extern "C"
{
  int* getptr()
  {
    int* p = new int;
    *p = 1024;
    allocated.push_back(p);
    return p;
  }
  void Unload()
  {
    for(auto e: allocated)
      delete e;
  }
}

The mod.cpp is compiled as:

g++ -shared mod.cpp -o mod.so -fPIC

Answer 1

dlopen("mod.so",RTLD_LAZY) returns NULL. Try this:

void* module = dlopen("./mod.so",RTLD_LAZY);
if (!module) {
    fprintf(stderr, "error in dlopen: %s\n", dlerror());
    return 1;
}