Lil Wayne gave concertgoers an ominous warning ... if you throw stuff onstage you're gonna get shot.
Wayne was performing Saturday night at the Cannabis Cup at NOS Events Center in San Bernardino, and he repeated the mantra we've heard him threaten before when people throw things onstage.
Listen to the clip ... he says, "I got New Orleans people with me and all they know how to throw back is shoot. They'll just shoot."
Apparently the venue had no problem with the threat, because the concert continued without incident.