git - Difference between single commit on branch and trunk -

i have seen questions diffing files none matches usecase.

the situation:

a - b - c - d (master)  \ e (tag) - f - g - h (my_branch) 

now see diff if had cherry-picked h onto d.

this happens when working on stable version of software , need send patch against trunk.

anyone know how can produce such diff?

to see difference between 2 commits, git diff h d.

editing in response comments

the fewest steps can think of is:

git checkout master git cherry-pick h --no-commit git diff --staged git reset --hard