let const_body = ecx.expr_block(ecx.block(span, stmts));
let const_item = ecx.item_const(span, Ident::new(kw::Underscore, span), const_ty, const_body);
let const_item = if is_stmt {
let const_body = ecx.expr_block(ecx.block(span, stmts));
let const_item = ecx.item_const(span, Ident::new(kw::Underscore, span), const_ty, const_body);
let const_item = if is_stmt {