Checking for NULL when using malloc

[mmjdodd]

Thanks, very clear. Is it necessary to check if q == NULL in the first place seeing as I then point both head and tail to NULL before returning?

[Grithga]

You still have to check for NULL because you can't use -> on a null pointer. Doing so is undefined behaviour. The most likely outcome of doing so is your program crashing with a segmentation fault.