Wiz Khalifa's Joint Makes George Clinton Cough Hard, Fumble on the Pass

Wiz Khalifa stars as George Clinton in the film "Spinning Gold" and the "Black and Yellow" rapper got to put his P-funk skills to the test performing alongside the man himself in Hollywood!!!

Both Wiz and George were front and center Wednesday night at Avalon for the "Spinning Gold" release party, jamming "Mothership Connection" tracks live for fans ... before they blasted off 4/20 style.

As the band was wrapping up the show, Wiz passed his joint to George, who happily indulged ... maybe a little too much. The legend started coughing, and when he tried to pass the J back to Wiz they dropped it. That KK must be mighty potent!!!

No flags on the party foul, though -- Wiz just brushed the dirt off of George's shoulder and saluted him for the performance.

TMZ Hip Hop recently spoke to George about Wiz's portrayal of him and gave it the classic movie critique of "two thumbs up," while noting how cool the rap star made him look to his younger family members.

We're thinking last night's performance also has him looking mighty wavy with his kinfolk!!!