Auto merge of #20 - tomaka:patch-1, r=pcwalton

Implement Send and Sync on SmallVec

Because of the core team's questionable decision of not implementing Send and Sync on raw pointers, we need to implement them manually.

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Author: bors-servo

lib.rs

@@ -83,6 +83,9 @@ enum SmallVecData<A: Array> {
     Heap { ptr: *mut A::Item, capacity: usize },
 }
 
+unsafe impl<A: Array + Send> Send for SmallVecData<A> {}
+unsafe impl<A: Array + Sync> Sync for SmallVecData<A> {}
+
 impl<A: Array> Drop for SmallVecData<A> {
     fn drop(&mut self) {
         unsafe {