[rustc.git] / src / librustc_error_codes / error_codes / E0669.md

Cannot convert inline assembly operand to a single LLVM value.

Erroneous code example:

```compile_fail,E0669
#![feature(llvm_asm)]

fn main() {
    unsafe {
        llvm_asm!("" :: "r"("")); // error!
    }
}
```

This error usually happens when trying to pass in a value to an input inline
assembly operand that is actually a pair of values. In particular, this can
happen when trying to pass in a slice, for instance a `&str`. In Rust, these
values are represented internally as a pair of values, the pointer and its
length. When passed as an input operand, this pair of values can not be
coerced into a register and thus we must fail with an error.
Commit	Line	Data
60c5eb7d XL	1	Cannot convert inline assembly operand to a single LLVM value.
60c5eb7d XL	2
f9f354fc XL	3	Erroneous code example:
	4
	5	```compile_fail,E0669
	6	#![feature(llvm_asm)]
	7
	8	fn main() {
	9	unsafe {
	10	llvm_asm!("" :: "r"("")); // error!
	11	}
	12	}
	13	```
	14
60c5eb7d XL	15	This error usually happens when trying to pass in a value to an input inline
	16	assembly operand that is actually a pair of values. In particular, this can
	17	happen when trying to pass in a slice, for instance a `&str`. In Rust, these
	18	values are represented internally as a pair of values, the pointer and its
	19	length. When passed as an input operand, this pair of values can not be
	20	coerced into a register and thus we must fail with an error.