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vbezhenar | 9 days ago

One small nitpick: you don't need check before `free` call, using `free(NULL)` is fine.

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t43562|9 days ago

You're right that it's not needed in my example but sometimes the thing that you're freeing has pointers inside it which themselves have to be freed first and in that case you need the if.

There are several other issues I haven't shown like what happens if you need to free something only when the return code is "FALSE" indicating that something failed.

This is not as nice as defer but up till now it was a comparatively nice way to deal with those functions which were really large and complicated and had many exit points.

Arch-TK|9 days ago

If you have something which contains pointers, you should have a destructor function for it, which itself should check if the pointer is not NULL before attempting to free any fields.

jagged-chisel|9 days ago

But it does keep one in the habit of using NULL checks.

david-gpu|9 days ago

It is pointless, because in Linux all you get is a virtual address. Physical backing is only allocated on first use.

In other words, the first time you access a "freshly allocated" non-null pointer you may get a page fault due to insufficient physical memory.