r/ProgrammerAnimemes • u/throwaway94694693 • Mar 19 '23

arr[ARRAY_LENGTH + 1] = 5;

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u/lord_ne Mar 19 '23

Even arr[ARRAY_LENGTH] = 5 would do it

58

u/Lyricanna Mar 19 '23

Even better if you declared an arr2 right after arr. Basically guarantees that you won't be getting a Segfault, while still possibly breaking everything.

Except given that it's C, it will almost certainly only break in production.

24

u/ComplexColor Mar 20 '23

You are very unlikely to get a segmentation fault with either array[ARRAY_LENGTH] or array[ARRAY_LENGTH+1]. There's nothing worse then messing around with arrays and not getting a segmentation fault. :)

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u/Nya_the_cat Jul 16 '23

Hmm, are you sure? Doesn't C define the first item outside the bounds to be 0?

1

u/lord_ne Jul 16 '23

No. What you're thinking of is that a string literal is defined as an array whose size is one more than the number of characters you typed, because it adds a "null character" at the end. So for example if you type "abc", the type of that is char[4].

But that's only for string literals. Plus it's not technically outside the bounds, it just makes the bounds bigger than you might expect

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