Should we check if memory allocations fail?

Question

I\'ve seen a lot of code that checks for NULL pointers whenever an allocation is made. This makes the code verbose, and if it\'s not done consistently, only when the program

Answer 1

Yes, you should check for a null return value from malloc. Even if you can't recover from the failure of memory allocation you should explicitly exit. Carrying on as though memory allocation had succeeded leaves your application in an inconsistent state and is likely to cause "undefined behavior" which should be avoided.

For example, you may end up writing inconsistent data to external storage which may hinder the ability of the next run of the application to recover. It's much safer to exit swiftly in a more controlled fashion.

Many applications that want to exit on allocation failure wrap malloc in a function that checks the return value and explicitly aborts on failure.

Arguably, this is one advantage of the C++ default new approach to throw an exception on allocation failure. It requires no effort to exit on memory allocation failure.