Possible Clues:

• Party goer finally dropping off? One's received wake-up call
• Vicar takes drug repeatedly, transfixed by rough wake-up call
• Military signal
• Call for soldiers, some of them by place of death, as heard in poem
• One popped by raver, all but a wake-up call
• Early-morning call always upset sick European
• It puts paid to the rest of the men
• Father English is not too good at start of evening - it's a wake-up call for anyone fighting in their sleep
• Early military calling
• The wake-up bugle call