do not use doc comments inside functions

Author: RalfJung

src/librustc_mir/transform/add_validation.rs

@@ -91,7 +91,7 @@ impl MirPass for AddValidation {
 
         let local_decls = mir.local_decls.clone(); // FIXME: Find a way to get rid of this clone.
 
-        /// Convert an lvalue to a validation operand.
+        // Convert an lvalue to a validation operand.
         let lval_to_operand = |lval: Lvalue<'tcx>| -> ValidationOperand<'tcx, Lvalue<'tcx>> {
             let (re, mutbl) = lval_context(&lval, &local_decls, tcx);
             let ty = lval.ty(&local_decls, tcx).to_ty(tcx);