Make Span and Symbol implement Send and Sync

Author: Zoxc

src/libsyntax_pos/lib.rs

@@ -92,10 +92,6 @@ impl SpanData {
     }
 }
 
-// The interner in thread-local, so `Span` shouldn't move between threads.
-impl !Send for Span {}
-impl !Sync for Span {}
-
 impl PartialOrd for Span {
     fn partial_cmp(&self, rhs: &Self) -> Option<Ordering> {
         PartialOrd::partial_cmp(&self.data(), &rhs.data())

src/libsyntax_pos/symbol.rs

@@ -83,10 +83,6 @@ impl Decodable for Ident {
 #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct Symbol(u32);
 
-// The interner in thread-local, so `Symbol` shouldn't move between threads.
-impl !Send for Symbol { }
-impl !Sync for Symbol { }
-
 impl Symbol {
     /// Maps a string to its interned representation.
     pub fn intern(string: &str) -> Self {