From 096a28607fb80c91e6e2ca64d9ef44c4e550e96c Mon Sep 17 00:00:00 2001
From: Niko Matsakis <niko@alum.mit.edu>
Date: Fri, 5 Dec 2014 17:01:33 -0800
Subject: librustc: Make `Copy` opt-in.

This change makes the compiler no longer infer whether types (structures
and enumerations) implement the `Copy` trait (and thus are implicitly
copyable). Rather, you must implement `Copy` yourself via `impl Copy for
MyType {}`.

A new warning has been added, `missing_copy_implementations`, to warn
you if a non-generic public type has been added that could have
implemented `Copy` but didn't.

For convenience, you may *temporarily* opt out of this behavior by using
`#![feature(opt_out_copy)]`. Note though that this feature gate will never be
accepted and will be removed by the time that 1.0 is released, so you should
transition your code away from using it.

This breaks code like:

    #[deriving(Show)]
    struct Point2D {
        x: int,
        y: int,
    }

    fn main() {
        let mypoint = Point2D {
            x: 1,
            y: 1,
        };
        let otherpoint = mypoint;
        println!("{}{}", mypoint, otherpoint);
    }

Change this code to:

    #[deriving(Show)]
    struct Point2D {
        x: int,
        y: int,
    }

    impl Copy for Point2D {}

    fn main() {
        let mypoint = Point2D {
            x: 1,
            y: 1,
        };
        let otherpoint = mypoint;
        println!("{}{}", mypoint, otherpoint);
    }

This is the backwards-incompatible part of #13231.

Part of RFC #3.

[breaking-change]
---
 src/libstd/io/net/addrinfo.rs | 11 +++++++++++
 src/libstd/io/net/ip.rs       |  5 +++++
 2 files changed, 16 insertions(+)

(limited to 'src/libstd/io/net')

diff --git a/src/libstd/io/net/addrinfo.rs b/src/libstd/io/net/addrinfo.rs
index fea8372733c..fc81ab7b57a 100644
--- a/src/libstd/io/net/addrinfo.rs
+++ b/src/libstd/io/net/addrinfo.rs
@@ -22,6 +22,7 @@ pub use self::Protocol::*;
 use iter::IteratorExt;
 use io::{IoResult};
 use io::net::ip::{SocketAddr, IpAddr};
+use kinds::Copy;
 use option::Option;
 use option::Option::{Some, None};
 use sys;
@@ -32,6 +33,8 @@ pub enum SocketType {
     Stream, Datagram, Raw
 }
 
+impl Copy for SocketType {}
+
 /// Flags which can be or'd into the `flags` field of a `Hint`. These are used
 /// to manipulate how a query is performed.
 ///
@@ -46,12 +49,16 @@ pub enum Flag {
     V4Mapped,
 }
 
+impl Copy for Flag {}
+
 /// A transport protocol associated with either a hint or a return value of
 /// `lookup`
 pub enum Protocol {
     TCP, UDP
 }
 
+impl Copy for Protocol {}
+
 /// This structure is used to provide hints when fetching addresses for a
 /// remote host to control how the lookup is performed.
 ///
@@ -64,6 +71,8 @@ pub struct Hint {
     pub flags: uint,
 }
 
+impl Copy for Hint {}
+
 pub struct Info {
     pub address: SocketAddr,
     pub family: uint,
@@ -72,6 +81,8 @@ pub struct Info {
     pub flags: uint,
 }
 
+impl Copy for Info {}
+
 /// Easy name resolution. Given a hostname, returns the list of IP addresses for
 /// that hostname.
 pub fn get_host_addresses(host: &str) -> IoResult<Vec<IpAddr>> {
diff --git a/src/libstd/io/net/ip.rs b/src/libstd/io/net/ip.rs
index 3fa6f4a6091..f59dd37c0da 100644
--- a/src/libstd/io/net/ip.rs
+++ b/src/libstd/io/net/ip.rs
@@ -18,6 +18,7 @@
 pub use self::IpAddr::*;
 
 use fmt;
+use kinds::Copy;
 use io::{mod, IoResult, IoError};
 use io::net;
 use iter::{Iterator, IteratorExt};
@@ -36,6 +37,8 @@ pub enum IpAddr {
     Ipv6Addr(u16, u16, u16, u16, u16, u16, u16, u16)
 }
 
+impl Copy for IpAddr {}
+
 impl fmt::Show for IpAddr {
     fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
         match *self {
@@ -67,6 +70,8 @@ pub struct SocketAddr {
     pub port: Port,
 }
 
+impl Copy for SocketAddr {}
+
 impl fmt::Show for SocketAddr {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         match self.ip {
-- 
cgit 1.4.1-3-g733a5