r/ProgrammerHumor • u/ClipboardCopyPaste • 2d ago

Meme bugIntroducedDebugging

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u/LostgamerFJ 2d ago

I'm not good enough at programming for this. What do the "free" and "malloc" functions do?

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u/LucyShortForLucas 2d ago

They are core C functions. malloc allocates N bytes of memory, free frees that memory. * is t he dereference operator, so *x is trying to dereference freed memory, which is undefined behavior

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u/LostgamerFJ 2d ago

That explains a lot. I mainly code in Java and python, as I'm a beginner and have never touched c

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u/conundorum 2d ago

That makes sense. Java in particular does a lot of this under the hood; anything that isn't a primitive is actually a reference (special C++-style pointer with non-pointer syntax), and new is a combination of malloc() & objection creation. (delete should be a combination of object destruction & free(), but they had to change how it works to accomodate the garbage collector.)

C (and C++) just makes you do the actual bookkeeping yourself.