Charity making communist angry (3,5)
I believe the answer is:
red cross
'charity' is the definition.
'communist angry' is the wordplay.
'communist' becomes 'red' (red can informally mean communist).
'angry' becomes 'cross' (cross can mean annoyed or angry).
'red'+'cross'='RED-CROSS'
'making' is the link.
(Other definitions for red cross that I've seen before include "International relief organisation" , "Medical group" , "International organisation for treatment of wounded in war" , "that brings relief!" , "Medical outfit" .)