Question

Hey all, just wondering whether the following would cause a memory leak?

char* a = "abcd"
char* b = new char[80];

strcpy(b, a);

delete[] b;

Will it delete the whole block of 80 or just the 4 characters copied into it by strcpy? Thanks!

Answer 1

You allocated 80 bytes into b, so delete[] will free 80 bytes. What you did with the array in the meantime is irrelevant.

(Unless, of course, you corrupted the heap, in which case delete[] will probably crash.)

EDIT: As others have pointed out, since b is an array, you need to use delete[] b; instead of delete b;. Some implementations might let you get away with that, but others won’t, and it would still be wrong.