The company I was working for had a fairly bad year (not "we're gone" but "we only grew 1% vs the usual 15-20%"). An email went out from the CEO advising no salary increases would happen that year.
I was 2 years in and due for a performance review.
In the performance review, I asked for a raise of 7% and highlighted the reasons. My manager countered with "we can't do raises this year". I countered with my performance for the last year and asked if he could review and let me know by the end of the week (the meeting was on a Monday).
He called a meeting with me on the Thursday and gave me the raise. He also asked me to keep it private.
My main lesson was: Don't accept blanket rules. Unless you're in government, you should still ask for the raise.