Don't show the explicit_iter_loop lint for arrays with more than 32 elements

The IntoIterator trait is currently not implemented for arrays with more than
32 elements, so for longer arrays, the iter() or iter_mut() methods must be
used.

src/loops.rs

@@ -199,7 +199,7 @@ fn is_ref_iterable_type(cx: &Context, e: &Expr) -> bool {
     // no walk_ptrs_ty: calling iter() on a reference can make sense because it
     // will allow further borrows afterwards
     let ty = cx.tcx.expr_ty(e);
-    is_array(ty) ||
+    is_iterable_array(ty) ||
         match_type(cx, ty, &VEC_PATH) ||
         match_type(cx, ty, &LL_PATH) ||
         match_type(cx, ty, &["std", "collections", "hash", "map", "HashMap"]) ||
@@ -210,9 +210,10 @@ fn is_ref_iterable_type(cx: &Context, e: &Expr) -> bool {
         match_type(cx, ty, &["collections", "btree", "set", "BTreeSet"])
 }
 
-fn is_array(ty: ty::Ty) -> bool {
+fn is_iterable_array(ty: ty::Ty) -> bool {
+    //IntoIterator is currently only implemented for array sizes <= 32 in rustc
     match ty.sty {
-        ty::TyArray(..) => true,
+        ty::TyArray(_, 0...32) => true,
         _ => false
     }
 }