Re: [avrdude-dev] Build error with SVN trunk

[Hannes Weisbach]

Am 17.05.2013 um 10:34 schrieb Joerg Wunsch:

> As Hannes Weisbach wrote:
> 
>>>> There was already a check in configure, which is now reactivated.
> 
>> Which is not necessary, since avrftdi requires libftdi-1.0 and
>> libftdi-1.0 declares TYPE_232H. This masks an error, where
>> libftdi-0.x is erroneously recognized as libftdi-1.0.  I made the
>> change to libftdi-1.0 because I want to use asynchronous transfers
>> in the future. Plus libftdi-0.x has not been updated since 9 months,
>> so I consider it deprecated.
> 
> I disagree.  9 months is nothing in opensource-land.  FreeBSD's
> libftdi port is still at 0.20, so please don't break support for older
> libftdi versions unless really necessary.  (I can take over the
> testing part for that if you want, I've got an FT2232D board and an
> FT232H sample module to try with.)
Thanks for the offer. Does it include libusb-1.0 with libusb-compat and 
libftdi-0.x too? ;)
> 
> 
> As you can see, about 1.5 years between releases are not unusual.
> Thus, arguing that some library has not been updated for 9 months is
> not useful, IMHO.
I didn't put that very well. My point is, that libftdi-0.x has been superseded 
by libftdi-1.0 (apparently necessitated by libusb-1.0) and thus is implicitly 
deprecated. Additionally, patches and bugfixes are apparently not back-ported 
from libftdi-1.0 to libftdi-0.x.
>  Besides, something not being *updated* for a while
> can mean it's just good enough for the job, has no known bugs, and is
> thus stable.
libusb-1.0 is considered finished and stable. To use libusb-1.0 one has to use 
libftdi-1.x.

lib{usb,ftdi}-1.0 also feature asynchronous I/O and it is my understanding that 
with this feature the ftdi_syncbb programmer will be able to work without 
threading, so we loose one dependency (pthreads) with "just" an update. The 
async I/O feature will probably also take care of that ominous deadlock problem 
in avrftdi. As I understand it, threading is just ftdi_syncbb's way of dealing 
with that.

So IMO, the update brings also the potential for cleaner/easier to understand 
code (hopefully).

Last but not least, FreeBSD has a libusb-1.0 compatible implementation. I don't 
know why they are not providing libftdi-1.x.

In retrospect: I didn't anticipate that so much would break. It's probably 
better to move all programmer at once to a new libusb and/or libftdi. (I still 
want the update ;))

Best regards,
Hannes