Deferred compensation is not compensation that can be used to support an IRA contribution. The IRS treats as supporting compensation on a W-2 the amount in box 1 minus the amount in box 11. Since both of these boxes show the same value, no IRA contribution can be based on this income.
Any IRA contributions that you already made based on the mistaken belief that this income would support the contributions are excess contributions subject to penalty unless distributed by an explicit return of contribution (not a regular distribution) by the due date of your tax return from any IRAs to which these contributions were made.
