Green’s Dictionary of Slang

fuck-it-all adj.

[fuck it! excl.]

laissez-faire, nonchalant, carefree.

[US]P. Thomas Down These Mean Streets (1970) 30: I felt a fuck-it-all attitude.
[US](con. 1945) E. Thompson Tattoo (1977) 362: At the gangway Jack snapped a fuck-it-all salute toward the fantail and went ashore.
[US]G. Indiana Rent Boy 108: Then, with a certain fuck-it-all bravado, she lifts the glass to her mouth and swallows it all down.