The deal would nearly double Gildan’s revenue, but there could be antitrust hurdles because both companies sell underwear, hosiery and shirts.

Gildan Activewear is buying HanesBrands for $2.2 billion, giving the basic apparel maker access to brands including Hanes and Maidenform.

In a major move to consolidate the basic side of the apparel industry, Gildan Activewear Inc. has agreed to buy HanesBrands Inc. in a cash and stock deal that values the innerwear giant stock at $2.2 billion.