@Harry1040
Generally this should be the your total world income including foreign income. Form 1116 for computation of allowable credit for the year uses form 1040 lines 11 ( AGI ), 15( Taxable Income ) and 16 ( total Tax ) Through all this machination what it trying to do determine ( in a ratiometric manner) that US tax that has been levied on the foreign in come. The credit you get is lesser of Foreign Taxes Paid and that imposed by US on the foreign in come.
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