Change the trivial cast lints to allow by default

25 files changed, 8 insertions, 32 deletions

diff --git a/src/libcollections/lib.rs b/src/libcollections/lib.rs
index 6a65c991c95..2e6a3527706 100644
--- a/src/libcollections/lib.rs
+++ b/src/libcollections/lib.rs
@@ -25,7 +25,6 @@
 #![doc(test(no_crate_inject))]
 
 #![allow(trivial_casts)]
-#![allow(trivial_numeric_casts)]
 #![feature(alloc)]
 #![feature(box_syntax)]
 #![feature(box_patterns)]
diff --git a/src/libcore/fmt/num.rs b/src/libcore/fmt/num.rs
index 56d2eabc095..49da99b97cb 100644
--- a/src/libcore/fmt/num.rs
+++ b/src/libcore/fmt/num.rs
@@ -13,7 +13,6 @@
 // FIXME: #6220 Implement floating point formatting
 
 #![allow(unsigned_negation)]
-#![allow(trivial_numeric_casts)]
 
 use fmt;
 use iter::IteratorExt;
diff --git a/src/libcore/num/i16.rs b/src/libcore/num/i16.rs
index efafce3fdef..5ea60d0d96d 100644
--- a/src/libcore/num/i16.rs
+++ b/src/libcore/num/i16.rs
@@ -12,6 +12,5 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 #![doc(primitive = "i16")]
-#![allow(trivial_numeric_casts)]
 
 int_module! { i16, 16 }
diff --git a/src/libcore/num/i32.rs b/src/libcore/num/i32.rs
index 72b0236a8d2..7d9faa998c1 100644
--- a/src/libcore/num/i32.rs
+++ b/src/libcore/num/i32.rs
@@ -12,6 +12,5 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 #![doc(primitive = "i32")]
-#![allow(trivial_numeric_casts)]
 
 int_module! { i32, 32 }
diff --git a/src/libcore/num/i64.rs b/src/libcore/num/i64.rs
index a64a4febd5a..5a70911387b 100644
--- a/src/libcore/num/i64.rs
+++ b/src/libcore/num/i64.rs
@@ -12,6 +12,5 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 #![doc(primitive = "i64")]
-#![allow(trivial_numeric_casts)]
 
 int_module! { i64, 64 }
diff --git a/src/libcore/num/i8.rs b/src/libcore/num/i8.rs
index 459814875ee..1d7d78ffa6c 100644
--- a/src/libcore/num/i8.rs
+++ b/src/libcore/num/i8.rs
@@ -12,6 +12,5 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 #![doc(primitive = "i8")]
-#![allow(trivial_numeric_casts)]
 
 int_module! { i8, 8 }
diff --git a/src/libcore/num/int_macros.rs b/src/libcore/num/int_macros.rs
index 675f568a960..fe0d6d13c4c 100644
--- a/src/libcore/num/int_macros.rs
+++ b/src/libcore/num/int_macros.rs
@@ -9,7 +9,6 @@
 // except according to those terms.
 
 #![doc(hidden)]
-#![allow(trivial_numeric_casts)]
 
 macro_rules! int_module { ($T:ty, $bits:expr) => (
 
diff --git a/src/libcore/num/isize.rs b/src/libcore/num/isize.rs
index 9af51a36748..0fd0d90b125 100644
--- a/src/libcore/num/isize.rs
+++ b/src/libcore/num/isize.rs
@@ -16,7 +16,6 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 #![doc(primitive = "isize")]
-#![allow(trivial_numeric_casts)]
 
 #[cfg(target_pointer_width = "32")]
 int_module! { isize, 32 }
diff --git a/src/libcore/num/mod.rs b/src/libcore/num/mod.rs
index 0eec875afc3..9ca7b48fbe5 100644
--- a/src/libcore/num/mod.rs
+++ b/src/libcore/num/mod.rs
@@ -14,7 +14,6 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 #![allow(missing_docs)]
-#![allow(trivial_numeric_casts)]
 
 use self::wrapping::{OverflowingOps, WrappingOps};
 
diff --git a/src/libcore/num/u16.rs b/src/libcore/num/u16.rs
index 289c5dbd08e..21635799a77 100644
--- a/src/libcore/num/u16.rs
+++ b/src/libcore/num/u16.rs
@@ -12,6 +12,5 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 #![doc(primitive = "u16")]
-#![allow(trivial_numeric_casts)]
 
 uint_module! { u16, i16, 16 }
diff --git a/src/libcore/num/u32.rs b/src/libcore/num/u32.rs
index 6d0b6b0e5ea..7d520770503 100644
--- a/src/libcore/num/u32.rs
+++ b/src/libcore/num/u32.rs
@@ -12,6 +12,5 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 #![doc(primitive = "u32")]
-#![allow(trivial_numeric_casts)]
 
 uint_module! { u32, i32, 32 }
diff --git a/src/libcore/num/u64.rs b/src/libcore/num/u64.rs
index bf8747fdb6e..f10822077dc 100644
--- a/src/libcore/num/u64.rs
+++ b/src/libcore/num/u64.rs
@@ -12,6 +12,5 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 #![doc(primitive = "u64")]
-#![allow(trivial_numeric_casts)]
 
 uint_module! { u64, i64, 64 }
diff --git a/src/libcore/num/u8.rs b/src/libcore/num/u8.rs
index 05199735d4a..3d6922b07b1 100644
--- a/src/libcore/num/u8.rs
+++ b/src/libcore/num/u8.rs
@@ -12,6 +12,5 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 #![doc(primitive = "u8")]
-#![allow(trivial_numeric_casts)]
 
 uint_module! { u8, i8, 8 }
diff --git a/src/libcore/num/uint_macros.rs b/src/libcore/num/uint_macros.rs
index c22f31cc57e..d0c4885ad00 100644
--- a/src/libcore/num/uint_macros.rs
+++ b/src/libcore/num/uint_macros.rs
@@ -9,7 +9,6 @@
 // except according to those terms.
 
 #![doc(hidden)]
-#![allow(trivial_numeric_casts)]
 
 macro_rules! uint_module { ($T:ty, $T_SIGNED:ty, $bits:expr) => (
 
diff --git a/src/libcore/num/usize.rs b/src/libcore/num/usize.rs
index 82dd3312782..602ef4fe45e 100644
--- a/src/libcore/num/usize.rs
+++ b/src/libcore/num/usize.rs
@@ -16,6 +16,5 @@
 
 #![stable(feature = "rust1", since = "1.0.0")]
 #![doc(primitive = "usize")]
-#![allow(trivial_numeric_casts)]
 
 uint_module! { usize, isize, ::isize::BITS }
diff --git a/src/librand/distributions/range.rs b/src/librand/distributions/range.rs
index a682fa85841..e6f27a28ffa 100644
--- a/src/librand/distributions/range.rs
+++ b/src/librand/distributions/range.rs
@@ -10,8 +10,6 @@
 
 //! Generating numbers between two others.
 
-#![allow(trivial_numeric_casts)]
-
 // this is surprisingly complicated to be both generic & correct
 
 use core::prelude::{PartialOrd};
diff --git a/src/librand/isaac.rs b/src/librand/isaac.rs
index 14bebe0cd91..7ea62b7fd3f 100644
--- a/src/librand/isaac.rs
+++ b/src/librand/isaac.rs
@@ -447,7 +447,6 @@ impl Rng for Isaac64Rng {
 
     #[inline]
     fn next_u64(&mut self) -> u64 {
-        #![allow(trivial_numeric_casts)]
         if self.cnt == 0 {
             // make some more numbers
             self.isaac64();
diff --git a/src/librustc/lib.rs b/src/librustc/lib.rs
index e8af07e4381..62ff7dd8131 100644
--- a/src/librustc/lib.rs
+++ b/src/librustc/lib.rs
@@ -48,7 +48,6 @@
 #![cfg_attr(test, feature(test))]
 
 #![allow(trivial_casts)]
-#![allow(trivial_numeric_casts)]
 
 extern crate arena;
 extern crate flate;
diff --git a/src/librustc/lint/builtin.rs b/src/librustc/lint/builtin.rs
index 2cc47f258f0..9093cd00ca0 100644
--- a/src/librustc/lint/builtin.rs
+++ b/src/librustc/lint/builtin.rs
@@ -102,13 +102,13 @@ declare_lint! {
 
 declare_lint! {
     pub TRIVIAL_CASTS,
-    Warn,
+    Allow,
     "detects trivial casts which could be removed"
 }
 
 declare_lint! {
     pub TRIVIAL_NUMERIC_CASTS,
-    Warn,
+    Allow,
     "detects trivial casts of numeric types which could be removed"
 }
 /// Does nothing as a lint pass, but registers some `Lint`s
diff --git a/src/librustc_llvm/lib.rs b/src/librustc_llvm/lib.rs
index 9d564fa56f5..d128e6f1a5f 100644
--- a/src/librustc_llvm/lib.rs
+++ b/src/librustc_llvm/lib.rs
@@ -15,7 +15,6 @@
 #![allow(non_snake_case)]
 #![allow(dead_code)]
 #![allow(trivial_casts)]
-#![allow(trivial_numeric_casts)]
 
 #![crate_name = "rustc_llvm"]
 #![unstable(feature = "rustc_private")]
diff --git a/src/librustc_trans/lib.rs b/src/librustc_trans/lib.rs
index 99a64156d66..a9147205f7d 100644
--- a/src/librustc_trans/lib.rs
+++ b/src/librustc_trans/lib.rs
@@ -44,7 +44,6 @@
 #![feature(path_relative_from)]
 
 #![allow(trivial_casts)]
-#![allow(trivial_numeric_casts)]
 
 extern crate arena;
 extern crate flate;
diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs
index 1e38a7d2d9f..3efe3a13562 100644
--- a/src/librustc_typeck/check/mod.rs
+++ b/src/librustc_typeck/check/mod.rs
@@ -1105,14 +1105,18 @@ fn check_cast<'a, 'tcx>(fcx: &FnCtxt<'a, 'tcx>, cast: &CastCheck<'tcx>) {
                 fcx.tcx().sess.add_lint(lint::builtin::TRIVIAL_NUMERIC_CASTS,
                                         e.id,
                                         span,
-                                        format!("trivial numeric cast: `{}` as `{}`",
+                                        format!("trivial numeric cast: `{}` as `{}`. Cast can be \
+                                                 replaced by coercion, this might require type \
+                                                 ascription or a temporary variable",
                                                 fcx.infcx().ty_to_string(t_e),
                                                 fcx.infcx().ty_to_string(t_1)));
             } else {
                 fcx.tcx().sess.add_lint(lint::builtin::TRIVIAL_CASTS,
                                         e.id,
                                         span,
-                                        format!("trivial cast: `{}` as `{}`",
+                                        format!("trivial cast: `{}` as `{}`. Cast can be \
+                                                 replaced by coercion, this might require type \
+                                                 ascription or a temporary variable",
                                                 fcx.infcx().ty_to_string(t_e),
                                                 fcx.infcx().ty_to_string(t_1)));
             }
@@ -4595,8 +4599,6 @@ pub fn check_enum_variants<'a,'tcx>(ccx: &CrateCtxt<'a,'tcx>,
                      ty: attr::IntType,
                      disr: ty::Disr) -> bool {
         fn uint_in_range(ccx: &CrateCtxt, ty: ast::UintTy, disr: ty::Disr) -> bool {
-            #![allow(trivial_numeric_casts)]
-
             match ty {
                 ast::TyU8 => disr as u8 as Disr == disr,
                 ast::TyU16 => disr as u16 as Disr == disr,
@@ -4625,7 +4627,6 @@ pub fn check_enum_variants<'a,'tcx>(ccx: &CrateCtxt<'a,'tcx>,
                           id: ast::NodeId,
                           hint: attr::ReprAttr)
                           -> Vec<Rc<ty::VariantInfo<'tcx>>> {
-        #![allow(trivial_numeric_casts)]
         use std::num::Int;
 
         let rty = ty::node_id_to_type(ccx.tcx, id);
diff --git a/src/libserialize/json.rs b/src/libserialize/json.rs
index 0d6ed91d529..acd27161064 100644
--- a/src/libserialize/json.rs
+++ b/src/libserialize/json.rs
@@ -2430,7 +2430,6 @@ macro_rules! to_json_impl_i64 {
     ($($t:ty), +) => (
         $(impl ToJson for $t {
             fn to_json(&self) -> Json {
-                #![allow(trivial_numeric_casts)]
                 Json::I64(*self as i64)
             }
         })+
@@ -2443,7 +2442,6 @@ macro_rules! to_json_impl_u64 {
     ($($t:ty), +) => (
         $(impl ToJson for $t {
             fn to_json(&self) -> Json {
-                #![allow(trivial_numeric_casts)]
                 Json::U64(*self as u64)
             }
         })+
diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs
index cca6bb747d4..f3fb98e8c66 100644
--- a/src/libstd/lib.rs
+++ b/src/libstd/lib.rs
@@ -136,7 +136,6 @@
 #![no_std]
 
 #![allow(trivial_casts)]
-#![allow(trivial_numeric_casts)]
 #![deny(missing_docs)]
 
 #[cfg(test)] extern crate test;
diff --git a/src/libsyntax/ext/quote.rs b/src/libsyntax/ext/quote.rs
index a25a6451918..c11ffe66e6c 100644
--- a/src/libsyntax/ext/quote.rs
+++ b/src/libsyntax/ext/quote.rs
@@ -262,7 +262,6 @@ pub mod rt {
         (unsigned, $t:ty, $tag:expr) => (
             impl ToSource for $t {
                 fn to_source(&self) -> String {
-                    #![allow(trivial_numeric_casts)]
                     let lit = ast::LitInt(*self as u64, ast::UnsignedIntLit($tag));
                     pprust::lit_to_string(&dummy_spanned(lit))
                 }