rust-lang/rust — pull request #15356 by pcwalton (2014-07-02 22:40:25+00:00)
Title: librustc: Take the parameter space into account when combining type

parameters.

This can break code that mistakenly used type parameters in place of
`Self`. For example, this will break:

trait Foo {
fn bar(u: X) -> Self {
u
}
}

Change this code to not contain a type error. For example:

trait Foo {
fn bar(_: X) -> Self {
self
}
}

Closes #15172.

[breaking-change]

r? @alexcrichton