Ilya Zakharevich on Sat, 16 Dec 2023 02:41:24 +0100


[Date Prev] [Date Next] [Thread Prev] [Thread Next] [Date Index] [Thread Index]

Re: libpari precision handling changes


On Fri, Dec 15, 2023 at 11:43:00PM +0100, Bill Allombert wrote:
> > > I committed a change to the way the precision is manipulated in the 
> > > C library.
> > > 
> > > Now the precision is a multiple of BITS_IN_LONG.
> > 
> > This is a major backwards-incompatible change.  Should not it better
> > be handled by introducing new names for macros and functions?  

> It has been documented since 2013 than one should not assume that 
> realprec==lg. 

> Anyway, I am available to fix any code that is affected.
> It is just a matter of using realprec, prec2nbits and nbits2prec properly.

It seems that I was not clear enough.  THE reason for changing the
names of macros and functions is not to make it easier to “fix any
code that is affected”.

The reason is to

  MAKE IT ABSOLUTELY OBVIOUS that “this piece of code” is affected.

You changed the ABI.  The “common rules of personal hygiene” say that
you NEED to change the names.

Hope this helps,
Ilya