Rollup merge of #36396 - athulappadan:Default-docs, r=bluss

Documentation of what Default does for each type

Addresses #36265
I haven't changed the following types due to doubts:

1)src/libstd/ffi/c_str.rs
2)src/libcore/iter/sources.rs
3)src/libcore/hash/mod.rs
4)src/libcore/hash/mod.rs
5)src/librustc/middle/privacy.rs

r? @steveklabnik

1 files changed, 1 insertions, 0 deletions

diff --git a/src/liballoc/rc.rs b/src/liballoc/rc.rs
index c24c7ca47ad..dadddbc2cb3 100644
--- a/src/liballoc/rc.rs
+++ b/src/liballoc/rc.rs
@@ -870,6 +870,7 @@ impl<T: ?Sized + fmt::Debug> fmt::Debug for Weak<T> {
 
 #[stable(feature = "downgraded_weak", since = "1.10.0")]
 impl<T> Default for Weak<T> {
+    /// Creates a new `Weak<T>`.
     fn default() -> Weak<T> {
         Weak::new()
     }