mv compiler to compiler/

compiler/rustc_error_codes/src/lib.rs

@@ -0,0 +1,14 @@
+//! This library is used to gather all error codes into one place,
+//! the goal being to make their maintenance easier.
+
+macro_rules! register_diagnostics {
+    ($($ecode:ident: $message:expr,)* ; $($code:ident,)*) => (
+        pub static DIAGNOSTICS: &[(&str, Option<&str>)] = &[
+            $( (stringify!($ecode), Some($message)), )*
+            $( (stringify!($code), None), )*
+        ];
+    )
+}
+
+mod error_codes;
+pub use error_codes::DIAGNOSTICS;