ada-indent-return

ada-indent-return is a variable defined in `ada-mode.el'.
Its value is

0

Documentation:
Indentation for 'return' relative to the matching 'function' statement.
If `ada-indent-return' is null or negative, the indentation is done relative to
the open parenthesis (if there is no parenthesis, `ada-broken-indent' is used).

An example is:
function A (B : Integer)
>>>>>return C;

You can customize this variable.