Cracked sign, end missing, swinging back, indicating wine (7)

I believe the answer is:

madeira

I'm a little stuck... Click here to teach me more about this clue!

'wine' is the definition.
(Madeira is an example)

'cracked sign end missing swinging back' is the wordplay.
'cracked' becomes 'mad' (cracked can informally mean mad).
'sign end missing swinging' becomes 'arie' (I can't justify this - if you can you should believe this answer much more).
'back' says the letters should be written backwards.
'arie' back-to-front is 'eira'.
'mad'+'eira'='MADEIRA'

'indicating' is the link.

Can you help me to learn more?

(Other definitions for madeira that I've seen before include "Portuguese island off northwest Africa" , "cake producer" , "Island in the Atlantic Ocean" , "Atlantic territory" , "Portuguese island, capital Funchal" .)

I've seen this clue in The Independent.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.