#### Note: this error code is no longer emitted by the compiler
The `instruction_set` attribute was malformed.

Erroneous code example:

```compile_fail
#![feature(isa_attribute)]

#[instruction_set()] // error: expected one argument
pub fn something() {}
fn main() {}
```

The parenthesized `instruction_set` attribute requires the parameter to be
specified:

```
#![feature(isa_attribute)]

#[cfg_attr(all(target_arch="arm", target_os="none"), instruction_set(arm::a32))]
fn something() {}
```

or:

```
#![feature(isa_attribute)]

#[cfg_attr(all(target_arch="arm", target_os="none"), instruction_set(arm::t32))]
fn something() {}
```

For more information see the [`instruction_set` attribute][isa-attribute]
section of the Reference.

[isa-attribute]: https://doc.rust-lang.org/reference/attributes/codegen.html
