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Comment by strictfp | Hacker News Reader

Abort and terminate? Jokes aside, error checking in c is important since if you don't do it you get "On error resume next" behavior.

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What does malloc() return if it fails?

    volatile char *x = 0;

And what happens if you write to that address?

    *x = 69;

The answers to these questions, whilst not defined by the C language, are portable enough.

The difference is in the error message you get. Adding "if (x == NULL) abort()" will display a backtrace near the error. To understand the cause of the segfault, you will have to follow the data flow in your favorite debugger.

What about the more common situation where the thing to be allocated is a (potentially large) array? These aren't always accessed sequentially. And the offset might be (indirectly) controlled by untrusted data from the wild.

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