Removal pass for anonymous parameters

Removes occurences of anonymous parameters from the
rustc codebase, as they are to be deprecated.

See issue #41686 and RFC 1685.

src/libcore/convert.rs

@@ -276,7 +276,7 @@ pub trait Into<T>: Sized {
 pub trait From<T>: Sized {
     /// Performs the conversion.
     #[stable(feature = "rust1", since = "1.0.0")]
-    fn from(T) -> Self;
+    fn from(t: T) -> Self;
 }
 
 /// An attempted conversion that consumes `self`, which may or may not be

src/libcore/hash/sip.rs

@@ -403,8 +403,8 @@ impl<S: Sip> Default for Hasher<S> {
 
 #[doc(hidden)]
 trait Sip {
-    fn c_rounds(&mut State);
-    fn d_rounds(&mut State);
+    fn c_rounds(_: &mut State);
+    fn d_rounds(_: &mut State);
 }
 
 #[derive(Debug, Clone, Default)]

src/libcore/ops.rs

@@ -2878,10 +2878,10 @@ pub trait Carrier {
     type Error;
 
     /// Create a `Carrier` from a success value.
-    fn from_success(Self::Success) -> Self;
+    fn from_success(_: Self::Success) -> Self;
 
     /// Create a `Carrier` from an error value.
-    fn from_error(Self::Error) -> Self;
+    fn from_error(_: Self::Error) -> Self;
 
     /// Translate this `Carrier` to another implementation of `Carrier` with the
     /// same associated types.