auto merge of #13415 : thestinger/rust/f128, r=alexcrichton

This currently requires linking against a library like libquadmath (or
libgcc), because compiler-rt barely has any support for this and most
hardware does not yet have 128-bit precision floating point. For this
reason, it's currently hidden behind a feature gate.

When compiler-rt is updated to trunk, some tests can be added for
constant evaluation since there will be support for the comparison
operators.

Closes #13381

4 files changed, 15 insertions, 1 deletions

diff --git a/src/libstd/intrinsics.rs b/src/libstd/intrinsics.rs
index 7f02ab28342..43b5f42163e 100644
--- a/src/libstd/intrinsics.rs
+++ b/src/libstd/intrinsics.rs
@@ -95,6 +95,8 @@ pub trait TyVisitor {
 
     fn visit_f32(&mut self) -> bool;
     fn visit_f64(&mut self) -> bool;
+    #[cfg(not(stage0))]
+    fn visit_f128(&mut self) -> bool;
 
     fn visit_char(&mut self) -> bool;
 
diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs
index 9325a0ad112..7cb07e8e551 100644
--- a/src/libstd/lib.rs
+++ b/src/libstd/lib.rs
@@ -52,11 +52,13 @@
        html_favicon_url = "http://www.rust-lang.org/favicon.ico",
        html_root_url = "http://static.rust-lang.org/doc/master")]
 #![feature(macro_rules, globs, asm, managed_boxes, thread_local, link_args,
-           simd, linkage, default_type_params, phase, concat_idents)]
+           simd, linkage, default_type_params, phase, concat_idents, quad_precision_float)]
 
 // Don't link to std. We are std.
 #![no_std]
 
+// NOTE: remove after snapshot
+#![allow(unknown_features)]
 #![deny(missing_doc)]
 
 // When testing libstd, bring in libuv as the I/O backend so tests can print
diff --git a/src/libstd/reflect.rs b/src/libstd/reflect.rs
index e64a6b86d02..45f214e26fb 100644
--- a/src/libstd/reflect.rs
+++ b/src/libstd/reflect.rs
@@ -176,6 +176,14 @@ impl<V:TyVisitor + MovePtr> TyVisitor for MovePtrAdaptor<V> {
         true
     }
 
+    #[cfg(not(stage0))]
+    fn visit_f128(&mut self) -> bool {
+        self.align_to::<f128>();
+        if ! self.inner.visit_f128() { return false; }
+        self.bump_past::<f128>();
+        true
+    }
+
     fn visit_char(&mut self) -> bool {
         self.align_to::<char>();
         if ! self.inner.visit_char() { return false; }
diff --git a/src/libstd/repr.rs b/src/libstd/repr.rs
index 668edbcc42f..61154502445 100644
--- a/src/libstd/repr.rs
+++ b/src/libstd/repr.rs
@@ -280,6 +280,8 @@ impl<'a> TyVisitor for ReprVisitor<'a> {
 
     fn visit_f32(&mut self) -> bool { self.write::<f32>() }
     fn visit_f64(&mut self) -> bool { self.write::<f64>() }
+    #[cfg(not(stage0))]
+    fn visit_f128(&mut self) -> bool { fail!("not implemented") }
 
     fn visit_char(&mut self) -> bool {
         self.get::<char>(|this, &ch| {