make std not use &A: Allocator instance

Author: RalfJung

library/std/src/alloc.rs

@@ -187,7 +187,7 @@ impl System {
             old_size => unsafe {
                 let new_ptr = self.alloc_impl(new_layout, zeroed)?;
                 ptr::copy_nonoverlapping(ptr.as_ptr(), new_ptr.as_mut_ptr(), old_size);
-                Allocator::deallocate(&self, ptr, old_layout);
+                Allocator::deallocate(self, ptr, old_layout);
                 Ok(new_ptr)
             },
         }
@@ -254,7 +254,7 @@ unsafe impl Allocator for System {
         match new_layout.size() {
             // SAFETY: conditions must be upheld by the caller
             0 => unsafe {
-                Allocator::deallocate(&self, ptr, old_layout);
+                Allocator::deallocate(self, ptr, old_layout);
                 Ok(NonNull::slice_from_raw_parts(new_layout.dangling(), 0))
             },
 
@@ -274,9 +274,9 @@ unsafe impl Allocator for System {
             // `new_ptr`. Thus, the call to `copy_nonoverlapping` is safe. The safety contract
             // for `dealloc` must be upheld by the caller.
             new_size => unsafe {
-                let new_ptr = Allocator::allocate(&self, new_layout)?;
+                let new_ptr = Allocator::allocate(self, new_layout)?;
                 ptr::copy_nonoverlapping(ptr.as_ptr(), new_ptr.as_mut_ptr(), new_size);
-                Allocator::deallocate(&self, ptr, old_layout);
+                Allocator::deallocate(self, ptr, old_layout);
                 Ok(new_ptr)
             },
         }