rust/src/librustc_error_codes/error_codes/E0661.md

338 B

An invalid syntax was passed to the second argument of an asm macro line.

Erroneous code example:

let a;
asm!("nop" : "r"(a));

Considering that this would be a long explanation, we instead recommend you to take a look at the unstable book: https://doc.rust-lang.org/unstable-book/language-features/asm.html