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This C++ program results in segmentation fault. It occurs in func() while trying to dereference a NULL pointer.

#include<iostream>

int *p = NULL;

int func()
{
  return *p;
}

int c = func();

int main()
{
  int a = 5;
  printf("%d",a);
  return 0;
}

Guessing your question is for Java, static blocks are executed before main.

What language and how does it crash?

In C:
- the startup code could be faulty
- gcc compiler allows you to do some funky stuff

In C++:
- define an external static duration object with some funky constructor (e.g., dereference a junk pointer inside the constructor to cause a seg fault)
- all the C stuff from above

Is that the program linked to a dynamic library and it is not available in the machine where the executable is running?

We can even get this program to crash:

int main() {
   return 0;
}

By using LD_LIBRARY_PRELOAD or equivalent.

The gcc compiler links some stuff before giving control to main. It can be found in the crt1.c. They will pass the arguments for the program.. argc and argv. So if something goes wrong here, the program will crash before main.