Declaring empty external functions #291

jmintb · 2023-08-21T18:51:38Z

jmintb
Aug 21, 2023

Hi

I am attempting to call printf and I believe that requires me to declare it, so something like this:

func @printf(i8)

I am a bit stuck on how to do that with melior. I have tried a few things with melior::dialect::func::func with no success.

Thanks for the awesome crate!

TLDR: How can I declare external functions?

Answered by raviqqe

You can pass an empty region as a body of the func.func operation (i.e. Region::new().) BTW, the example in the documentation seems to be wrong as FAQ and symbol visibility documentation actually says external function definitions must have private visibility. https://mlir.llvm.org/getting_started/Faq/#whats-with-op-symbol-declaration-cannot-have-public-visibility

You can pass an empty region as a body of the func.func operation (i.e. Region::new().) BTW, the example in the documentation seems to be wrong as FAQ and symbol visibility documentation actually says external function definitions must have private visibility. https://mlir.llvm.org/getting_started/Faq/#whats-with-op-symbol-declaration-cannot-have-public-visibility

Awesome thanks!