How to fix this C++ UBSAN vptr runtime error (runtime error: member call on address)

Question

I enabled ubsan test (-fsanitize=undefined) in my project and found some ubsan runtime errors. Can anyone help me find why it failed here? How to fix this issue on GCC and Clang?

Here is the lib.so module which includes lib.h and lib.cpp.

lib.h:

#ifndef LIB_H
#define LIB_H

#ifdef API_EXPORTS
   #define API __attribute__((visibility("default")))
#else
   #define API 
#endif

class API Exception
{
public:
     virtual ~ Exception() = 0;
     void SetReporter();
};

class API FileException : public Exception
{
public:
   ~FileException();
};

#endif

lib.cpp:

#include "lib.h"

Exception::~Exception() = default;

FileException::~FileException() = default;

void Exception::SetReporter()
{

}

Here is the executable module that will call lib.so module:

main.cpp

#include "lib.h"

int main(void) {
    FileException ex;
    ex.SetReporter();

    return 0;
}

Build the modules (lib.so and main) and run main, there are runtime errors:

build_run_gcc.sh

#!/bin/bash

# Test gcc version
gcc --version

# Build the API library
g++ -fPIC -D API_EXPORTS -o lib.so -shared lib.cpp -fvisibility=hidden -Wall -fsanitize=undefined -lubsan

# Build the main
g++ -o main main.cpp ./lib.so -fvisibility=hidden -Wall -fsanitize=undefined -lubsan

# Test main
./main

Errors:

main.cpp:5:19: runtime error: member call on address 0x7ffcb88a8c60 which does not point to an object of type 'Exception'
0x7ffcb88a8c60: note: object is of type 'FileException'
 14 56 00 00  48 cd 41 3d 14 56 00 00  00 fa 14 fd f4 29 3f 51  60 8d 8a b8 fc 7f 00 00  00 00 00 00
              ^~~~~~~~~~~~~~~~~~~~~~~
              vptr for 'FileException'