diff --git a/Cargo.toml b/Cargo.toml
index 39a8520..a644af2 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -21,13 +21,9 @@
 unicode-xid = "0.1"
 
 [features]
-
 # When enabled: act as a shim around the nightly compiler's proc_macro crate.
 # This requires a nightly compiler.
 #
 # When disabled: emulate the same API as the nightly compiler's proc_macro crate
 # but in a way that works on all stable compilers >=1.15.0.
 nightly = []
-
-# Deprecated; use "nightly" instead.
-unstable = ["nightly"]
diff --git a/src/lib.rs b/src/lib.rs
index 3f9d57a..38439c8 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -146,13 +146,6 @@
 #[derive(Copy, Clone)]
 pub struct Span(imp::Span);
 
-#[doc(hidden)]
-impl Default for Span {
-    fn default() -> Span {
-        Span(imp::Span::def_site())
-    }
-}
-
 impl Span {
     pub fn call_site() -> Span {
         Span(imp::Span::call_site())
@@ -211,7 +204,7 @@
 
 impl From<TokenNode> for TokenTree {
     fn from(kind: TokenNode) -> TokenTree {
-        TokenTree { span: Span::default(), kind: kind }
+        TokenTree { span: Span::def_site(), kind: kind }
     }
 }