One of the approaches to freeing memory is to call free right after the last usage of a pointer (in our case it's the loop which calls inline_stack_push(sv_2mortal(newSViv(c_array[i])));) and set it to NULL afterwards.

Setting a pointer to NULL serves double purpose:

  1. Checking for NULL is very easy, checking if non-NULL pointer is valid is very complex at best
  2. If you defensively call free(c_array) in another part of the program, free(NULL) would be safe on modern libcs, while free of a freed pointer causes memory corruption

In reply to Re^3: Wrapping a C shared library with Perl and XS by Anonymous Monk
in thread Wrapping a C shared library with Perl and XS by stevieb

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