The potential impact of global tariffs is a big reason estimates for the upcoming earnings season that starts in mid-July are gloomy. Companies are already starting to issue warnings: Earlier this week, FedEx Corp. said that its profit would be worse than expected this quarter and declined to offer guidance for the rest of the year, citing an 鈥渦ncertain global demand environment.鈥 General Mills Inc. echoed the concern, projecting a lower adjusted profit as value-seeking consumers feel pressured by tariffs, conflicts around the world and shifting regulations.