Function launch_kernel 

pub fn launch_kernel(
    func: u64,
    grid: (u32, u32, u32),
    block: (u32, u32, u32),
    shared_bytes: u32,
    stream: u64,
    params: &mut [*mut c_void],
) -> Result<()>

2026-09-25: cuLaunchKernel with extra = NULL. Each params entry must point at a live argument of the type the kernel expects, until this returns.