This is under the heading of "One Definition Rule" in the Standard, in a
paragraph explaining what it means for an object or non-overloaded function
to be 'used': "A virtual member function is used if it is not pure."
The subsequent paragraph says this:
"Every program shall contain exactly one definition of every non-inline
function or object that is used in that program; no diagnostic required."
Is that saying that a virtual member function must either be pure, or be
fully defined if a declaration for it appears in the translation unit,
regardless of whether it is actually called?
I believe the relevant wording is unchanged from this version:
http://www.kuzbass.ru:8086/docs/isocpp/basic.html
--
NOUN:1. Money or property bequeathed to another by will. 2. Something handed
down from an ancestor or a predecessor or from the past: a legacy of
religious freedom. ETYMOLOGY: MidE legacie, office of a deputy, from OF,
from ML legatia, from L legare, to depute, bequeath. www.bartleby.com/61/