Moving the kernel to modern C [LWN.net]

Moving the kernel to modern C

Posted Feb 27, 2022 16:04 UTC (Sun) by marcH (subscriber, #57642)
In reply to: Moving the kernel to modern C by camhusmj38
Parent article: Moving the kernel to modern C

Why would be the purpose of a declaration without an explicit type?

How would a typeless declaration help the people in this thread who complain about not finding declarations? If not the type, what else are they looking for?

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Moving the kernel to modern C

Posted Feb 27, 2022 18:55 UTC (Sun) by camhusmj38 (subscriber, #99234) [Link] (1 responses)

The declaration has a type - it’s inferred from the initialiser. It’s really only appropriate with local variables.

Moving the kernel to modern C

Posted Feb 27, 2022 20:49 UTC (Sun) by marcH (subscriber, #57642) [Link]

I see nothing factually wrong in your last two comments above but I really don't understand why they're posted as replies to mine. I'm afraid you're misunderstanding my points and questions.

Moving the kernel to modern C

Posted Feb 27, 2022 19:06 UTC (Sun) by mathstuf (subscriber, #69389) [Link]

In Rust, it can move the lifetime of a variable around. So if I have some code that needs to live for the outer scope, but is only "known" in some nested place, I can use `let somename;` on a block in the right place, initialize it where the data is available, and continue on. I've used this before to keep a string alive long enough for a context where it may have been either allocated (and therefore need a place to hang its destructor) or came from some other string that lived longer than the function anyways.