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Conditional Breakpoints with Pointers


in gdb, how do i set a conditional breakpoint depending on value of pointer keeping in mind that i have to check if pointer is null before dereferencing pointer?

here is an example of code i'm trying to debug:
    #include <iostream>
    using namespace std;
  
    int main () {
      int *i[10];
      int *j = NULL;
      int k;
  
      i[4] = new int;
      *i[4] = 8;
  
      for (k=0; k < 10; k++) {
        j = i[k];
      }
  
      return 0;
    }

i set conditional breakpoint at line "j=i[k]" but i got a seg fault:
    (gdb) b 14 if j && *j == 8
    (gdb) r
    Starting program: /nfs/blahblah/a.out
    Failed to read a valid object file image from memory.
    Program received signal SIGSEGV, Segmentation fault.

does anybody know why there is a segfault?


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