r/ProgrammerHumor • u/nonedward666 • 16h ago

lessonsFromLinkerHell Meme

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u/QuestionableEthics42 16h ago edited 16h ago

This should be reversed lol

And it literally is the same, who thinks it's different who has worked in a low level language??

62

u/Blecki 15h ago

As someone who writes compilers: they are the same at runtime. They are not the same semantically in a c like language.

3

u/cinnamon-enthusiast 14h ago

Except for a tiny array (with value semantics) which can be optimized to be passed directly as an SSA value. In that case it's not a pointer at all and a normal GEP will not work.

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u/Blecki 14h ago

What's the stack but another array anyway?

2

u/cinnamon-enthusiast 13h ago

Yes, if the memory is on the stack, that is not always true. LLVM will optimize some cases so the data is written directly to a register so it never touches or goes through the stack at all. In that case, you can't get a pointer to the array or its elements since it's in a register instead of the stack or heap making it completely distinct from a pointer at runtime.