Auto merge of #36030 - Manishearth:rollup, r=Manishearth

Rollup of 7 pull requests

- Successful merges: #35124, #35877, #35953, #36002, #36004, #36005, #36014
- Failed merges:

1 files changed, 4 insertions, 18 deletions

diff --git a/src/libstd/error.rs b/src/libstd/error.rs
index 44595361fb5..ab537f39bf9 100644
--- a/src/libstd/error.rs
+++ b/src/libstd/error.rs
@@ -54,7 +54,6 @@ use fmt::{self, Debug, Display};
 use marker::Reflect;
 use mem::transmute;
 use num;
-use raw::TraitObject;
 use str;
 use string;
 
@@ -326,11 +325,7 @@ impl Error + 'static {
     pub fn downcast_ref<T: Error + 'static>(&self) -> Option<&T> {
         if self.is::<T>() {
             unsafe {
-                // Get the raw representation of the trait object
-                let to: TraitObject = transmute(self);
-
-                // Extract the data pointer
-                Some(&*(to.data as *const T))
+                Some(&*(self as *const Error as *const T))
             }
         } else {
             None
@@ -344,11 +339,7 @@ impl Error + 'static {
     pub fn downcast_mut<T: Error + 'static>(&mut self) -> Option<&mut T> {
         if self.is::<T>() {
             unsafe {
-                // Get the raw representation of the trait object
-                let to: TraitObject = transmute(self);
-
-                // Extract the data pointer
-                Some(&mut *(to.data as *const T as *mut T))
+                Some(&mut *(self as *mut Error as *mut T))
             }
         } else {
             None
@@ -409,13 +400,8 @@ impl Error {
     pub fn downcast<T: Error + 'static>(self: Box<Self>) -> Result<Box<T>, Box<Error>> {
         if self.is::<T>() {
             unsafe {
-                // Get the raw representation of the trait object
-                let raw = Box::into_raw(self);
-                let to: TraitObject =
-                    transmute::<*mut Error, TraitObject>(raw);
-
-                // Extract the data pointer
-                Ok(Box::from_raw(to.data as *mut T))
+                let raw: *mut Error = Box::into_raw(self);
+                Ok(Box::from_raw(raw as *mut T))
             }
         } else {
             Err(self)