`intrinsics` -- `as *mut T` not always put on the same line in libarena/lib.rs (on Rust repo)

[Kagamihime]

Hello,

I have tried to submit a PR ( rust-lang/rust#47069 ) on the Rust repo after running rustfmt on the libarena crate but it seems like there are some formatting issues:

• on lines 136-137 the construct intrinsics -- as *mut T has been split on two lines
• but on line 367 the construct intrinsics -- as *mut u8 has been put on the same line and there is a comma added after as *mut u8

It seems as if it is not an expected result, so I've decided to submit this issue (my very first issue).

I've used rustfmt-nightly 0.3.4 without options to get this.

[topecongiro]

Reduced example:

Input

fn main() {
    self.ptr.set(intrinsics::arith_offset(self.ptr.get() as *mut u8, 1) as *mut T);
    self.ptr.set(intrinsics::arith_offset(self.ptr.get(), mem::size_of::<T>() as isize) as *mut u8);
}

Output

fn main() {
    self.ptr
        .set(intrinsics::arith_offset(self.ptr.get() as *mut u8, 1)
            as *mut T);
    self.ptr
        .set(intrinsics::arith_offset(self.ptr.get(), mem::size_of::<T>() as isize) as *mut u8);
}