This is the this
adjustment necessary when making a call to f
with a pointer to a
D
. It is either zero if f
is found in D
or the same as __offsetof_base(D,B)
, where B
is a
nonvirtual base class of D
that contains f
.
Where D
is a class type and f
is a nonstatic member
function defined in D
or a nonvirtual base class of D
.
If __mcall_this_offset(D,f)
is used when f
is found in a
virtual base class of D
it returns an arbitrary value designed to cause an
assembly error if used. This is so that such invalid uses of
__mcall_this_offset
can occur in sections of assembly code that are to be
skipped.