Question about MODES_TIEABLE_P

[Michael Matz]

Hi,

On Thu, 23 Oct 2003, John Lu wrote:

> It also states that it is highly desirable for modes to be tieable.
> Based on this, should every port have MODES_TIEABLE_P() return true
> if MODE1==MODE2?

My first reaction was going to say "not needed, because this macro is
never called with M1 == M2".  After a quick look at the sources this isn't
true.  So yes, MODES_TIEABLE_P should return 1 if M1==M2, at least if the
port doesn't want to pessimize code.  Maybe it would be better to ensure
what I initially thought was guaranteed, so that port maintainers don't
have to care about this, though.


Ciao,
Michael.