Rollup merge of rust-lang#49101 - mark-i-m:stabilize_i128, r=nagisa

Stabilize 128-bit integers 🎉

cc rust-lang#35118

EDIT: This should be merged only after the following have been merged:
- [x] rust-lang/compiler-builtins#236
- [x] rust-lang/book#1230

Author: alexcrichton

src/doc/unstable-book/src/language-features/i128-type.md

@@ -0,0 +1,18 @@
+# `repr128`
+
+The tracking issue for this feature is: [#35118]
+
+[#35118]: https://github.com/rust-lang/rust/issues/35118
+
+------------------------
+
+The `repr128` feature adds support for `#[repr(u128)]` on `enum`s.
+
+```rust
+#![feature(repr128)]
+
+#[repr(u128)]
+enum Foo {
+    Bar(u64),
+}
+```

src/doc/unstable-book/src/language-features/repr128.md

@@ -10,7 +10,7 @@
 
 #![deny(warnings)]
 
-#![feature(i128_type)]
+#![cfg_attr(stage0, feature(i128_type))]
 #![feature(rand)]
 #![feature(repr_simd)]
 #![feature(test)]

src/liballoc/benches/lib.rs

@@ -97,7 +97,7 @@
 #![feature(from_ref)]
 #![feature(fundamental)]
 #![feature(generic_param_attrs)]
-#![feature(i128_type)]
+#![cfg_attr(stage0, feature(i128_type))]
 #![feature(iter_rfold)]
 #![feature(lang_items)]
 #![feature(needs_allocator)]

src/liballoc/lib.rs

@@ -308,7 +308,7 @@ pub trait Hasher {
     }
     /// Writes a single `u128` into this hasher.
     #[inline]
-    #[unstable(feature = "i128", issue = "35118")]
+    #[stable(feature = "i128", since = "1.26.0")]
     fn write_u128(&mut self, i: u128) {
         self.write(&unsafe { mem::transmute::<_, [u8; 16]>(i) })
     }
@@ -348,7 +348,7 @@ pub trait Hasher {
     }
     /// Writes a single `i128` into this hasher.
     #[inline]
-    #[unstable(feature = "i128", issue = "35118")]
+    #[stable(feature = "i128", since = "1.26.0")]
     fn write_i128(&mut self, i: i128) {
         self.write_u128(i as u128)
     }

src/libcompiler_builtins

@@ -78,7 +78,7 @@
 #![feature(doc_spotlight)]
 #![feature(fn_must_use)]
 #![feature(fundamental)]
-#![feature(i128_type)]
+#![cfg_attr(stage0, feature(i128_type))]
 #![cfg_attr(stage0, feature(inclusive_range_syntax))]
 #![feature(intrinsics)]
 #![feature(iterator_flatten)]

src/libcore/hash/mod.rs

@@ -12,6 +12,6 @@
 //!
 //! *[See also the `i128` primitive type](../../std/primitive.i128.html).*
 
-#![unstable(feature = "i128", issue="35118")]
+#![stable(feature = "i128", since = "1.26.0")]
 
-int_module! { i128, #[unstable(feature = "i128", issue="35118")] }
+int_module! { i128, #[stable(feature = "i128", since="1.26.0")] }

src/libcore/lib.rs

@@ -1635,11 +1635,7 @@ impl i64 {
 #[lang = "i128"]
 impl i128 {
     int_impl! { i128, i128, u128, 128, -170141183460469231731687303715884105728,
-        170141183460469231731687303715884105727, "#![feature(i128_type)]
-#![feature(i128)]
-# fn main() {
-", "
-# }" }
+        170141183460469231731687303715884105727, "", "" }
 }
 
 #[cfg(target_pointer_width = "16")]
@@ -3493,12 +3489,7 @@ impl u64 {
 
 #[lang = "u128"]
 impl u128 {
-    uint_impl! { u128, u128, 128, 340282366920938463463374607431768211455, "#![feature(i128_type)]
-#![feature(i128)]
-
-# fn main() {
-", "
-# }" }
+    uint_impl! { u128, u128, 128, 340282366920938463463374607431768211455, "", "" }
 }
 
 #[cfg(target_pointer_width = "16")]
@@ -4055,39 +4046,39 @@ macro_rules! impl_from {
 impl_from! { u8, u16, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 impl_from! { u8, u32, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 impl_from! { u8, u64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
-impl_from! { u8, u128, #[unstable(feature = "i128", issue = "35118")] }
+impl_from! { u8, u128, #[stable(feature = "i128", since = "1.26.0")] }
 impl_from! { u8, usize, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 impl_from! { u16, u32, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 impl_from! { u16, u64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
-impl_from! { u16, u128, #[unstable(feature = "i128", issue = "35118")] }
+impl_from! { u16, u128, #[stable(feature = "i128", since = "1.26.0")] }
 impl_from! { u32, u64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
-impl_from! { u32, u128, #[unstable(feature = "i128", issue = "35118")] }
-impl_from! { u64, u128, #[unstable(feature = "i128", issue = "35118")] }
+impl_from! { u32, u128, #[stable(feature = "i128", since = "1.26.0")] }
+impl_from! { u64, u128, #[stable(feature = "i128", since = "1.26.0")] }
 
 // Signed -> Signed
 impl_from! { i8, i16, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 impl_from! { i8, i32, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 impl_from! { i8, i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
-impl_from! { i8, i128, #[unstable(feature = "i128", issue = "35118")] }
+impl_from! { i8, i128, #[stable(feature = "i128", since = "1.26.0")] }
 impl_from! { i8, isize, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 impl_from! { i16, i32, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 impl_from! { i16, i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
-impl_from! { i16, i128, #[unstable(feature = "i128", issue = "35118")] }
+impl_from! { i16, i128, #[stable(feature = "i128", since = "1.26.0")] }
 impl_from! { i32, i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
-impl_from! { i32, i128, #[unstable(feature = "i128", issue = "35118")] }
-impl_from! { i64, i128, #[unstable(feature = "i128", issue = "35118")] }
+impl_from! { i32, i128, #[stable(feature = "i128", since = "1.26.0")] }
+impl_from! { i64, i128, #[stable(feature = "i128", since = "1.26.0")] }
 
 // Unsigned -> Signed
 impl_from! { u8, i16, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 impl_from! { u8, i32, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 impl_from! { u8, i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
-impl_from! { u8, i128, #[unstable(feature = "i128", issue = "35118")] }
+impl_from! { u8, i128, #[stable(feature = "i128", since = "1.26.0")] }
 impl_from! { u16, i32, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
 impl_from! { u16, i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
-impl_from! { u16, i128, #[unstable(feature = "i128", issue = "35118")] }
+impl_from! { u16, i128, #[stable(feature = "i128", since = "1.26.0")] }
 impl_from! { u32, i64, #[stable(feature = "lossless_int_conv", since = "1.5.0")] }
-impl_from! { u32, i128, #[unstable(feature = "i128", issue = "35118")] }
-impl_from! { u64, i128, #[unstable(feature = "i128", issue = "35118")] }
+impl_from! { u32, i128, #[stable(feature = "i128", since = "1.26.0")] }
+impl_from! { u64, i128, #[stable(feature = "i128", since = "1.26.0")] }
 
 // Note: integers can only be represented with full precision in a float if
 // they fit in the significand, which is 24 bits in f32 and 53 bits in f64.

src/libcore/num/i128.rs

@@ -12,5 +12,5 @@
 //!
 //! *[See also the `u128` primitive type](../../std/primitive.u128.html).*
 
-#![unstable(feature = "i128", issue="35118")]
-uint_module! { u128, #[unstable(feature = "i128", issue="35118")] }
+#![stable(feature = "i128", since = "1.26.0")]
+uint_module! { u128, #[stable(feature = "i128", since="1.26.0")] }