---

yaml
---
r: 234905
b: refs/heads/stable
c: 8cf22b5
h: refs/heads/master
i:
  234903: 610d11d
v: v3

Author: bors

[refs]

@@ -29,7 +29,7 @@ refs/heads/tmp: afae2ff723393b3ab4ccffef6ac7c6d1809e2da0
 refs/tags/1.0.0-alpha.2: 4c705f6bc559886632d3871b04f58aab093bfa2f
 refs/tags/homu-tmp: f859507de8c410b648d934d8f5ec1c52daac971d
 refs/tags/1.0.0-beta: 8cbb92b53468ee2b0c2d3eeb8567005953d40828
-refs/heads/stable: 0716da555f5da1d0039167c567853ac5b7cbb1a6
+refs/heads/stable: 8cf22b5eaf2b442fb2461a69c89d6c6011350f49
 refs/tags/1.0.0: 55bd4f8ff2b323f317ae89e254ce87162d52a375
 refs/tags/1.1.0: bc3c16f09287e5545c1d3f76b7abd54f2eca868b
 refs/tags/1.2.0: f557861f822c34f07270347b94b5280de20a597e

branches/stable/src/doc/trpl/ffi.md

@@ -309,8 +309,8 @@ and invokes callbacks from there.
 In these cases access to Rust data structures inside the callbacks is
 especially unsafe and proper synchronization mechanisms must be used.
 Besides classical synchronization mechanisms like mutexes, one possibility in
-Rust is to use channels (in `std::comm`) to forward data from the C thread
-that invoked the callback into a Rust thread.
+Rust is to use channels (in `std::sync::mpsc`) to forward data from the C
+thread that invoked the callback into a Rust thread.
 
 If an asynchronous callback targets a special object in the Rust address space
 it is also absolutely necessary that no more callbacks are performed by the

branches/stable/src/librustc/diagnostics.rs

@@ -984,6 +984,57 @@ From [RFC 246]:
 [RFC 246]: https://github.com/rust-lang/rfcs/pull/246
 "##,
 
+E0395: r##"
+The value assigned to a constant expression must be known at compile time,
+which is not the case when comparing raw pointers. Erroneous code example:
+
+```
+static foo: i32 = 42;
+static bar: i32 = 43;
+
+static baz: bool = { (&foo as *const i32) == (&bar as *const i32) };
+// error: raw pointers cannot be compared in statics!
+```
+
+Please check that the result of the comparison can be determined at compile time
+or isn't assigned to a constant expression. Example:
+
+```
+static foo: i32 = 42;
+static bar: i32 = 43;
+
+let baz: bool = { (&foo as *const i32) == (&bar as *const i32) };
+// baz isn't a constant expression so it's ok
+```
+"##,
+
+E0396: r##"
+The value assigned to a constant expression must be known at compile time,
+which is not the case when dereferencing raw pointers. Erroneous code
+example:
+
+```
+const foo: i32 = 42;
+const baz: *const i32 = (&foo as *const i32);
+
+const deref: i32 = *baz;
+// error: raw pointers cannot be dereferenced in constants
+```
+
+To fix this error, please do not assign this value to a constant expression.
+Example:
+
+```
+const foo: i32 = 42;
+const baz: *const i32 = (&foo as *const i32);
+
+unsafe { let deref: i32 = *baz; }
+// baz isn't a constant expression so it's ok
+```
+
+You'll also note that this assignment must be done in an unsafe block!
+"##,
+
 E0397: r##"
 It is not allowed for a mutable static to allocate or have destructors. For
 example:
@@ -1039,7 +1090,5 @@ register_diagnostics! {
     E0314, // closure outlives stack frame
     E0315, // cannot invoke closure outside of its lifetime
     E0316, // nested quantification of lifetimes
-    E0370, // discriminant overflow
-    E0395, // pointer comparison in const-expr
-    E0396  // pointer dereference in const-expr
+    E0370  // discriminant overflow
 }

branches/stable/src/librustc_typeck/diagnostics.rs

@@ -1458,6 +1458,42 @@ impl Foo for Bar {
 ```
 "##,
 
+E0327: r##"
+You cannot use associated items other than constant items as patterns. This
+includes method items. Example of erroneous code:
+
+```
+enum B {}
+
+impl B {
+    fn bb() -> i32 { 0 }
+}
+
+fn main() {
+    match 0 {
+        B::bb => {} // error: associated items in match patterns must
+                    // be constants
+    }
+}
+```
+
+Please check that you're not using a method as a pattern. Example:
+
+```
+enum B {
+    ba,
+    bb
+}
+
+fn main() {
+    match B::ba {
+        B::bb => {} // ok!
+        _ => {}
+    }
+}
+```
+"##,
+
 E0368: r##"
 This error indicates that a binary assignment operator like `+=` or `^=` was
 applied to the wrong types. For example:
@@ -1640,7 +1676,6 @@ register_diagnostics! {
     E0323, // implemented an associated const when another trait item expected
     E0324, // implemented a method when another trait item expected
     E0325, // implemented an associated type when another trait item expected
-    E0327, // referred to method instead of constant in match pattern
     E0328, // cannot implement Unsize explicitly
     E0329, // associated const depends on type parameter or Self.
     E0366, // dropck forbid specialization to concrete type or region