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Re: eCos 3.0 beta 1 punch list #2
- From: Jonathan Larmour <jifl at eCosCentric dot com>
- To: Bart Veer <bartv at ecoscentric dot com>
- Cc: John Dallaway <john at dallaway dot org dot uk>, ecos-maintainers at ecos dot sourceware dot org
- Date: Tue, 17 Feb 2009 01:29:01 +0000
- Subject: Re: eCos 3.0 beta 1 punch list #2
- References: <4992951D.email@example.com> <firstname.lastname@example.org>
Bart Veer wrote:
In theory there is one more change to go in: updating the flash
subsystem to use a prioritized constructor, and associated API
changes. Effectively this would replace explicit calls of
cyg_flash_init() with automatic initialization via a C++ static
constructor. That should simplify higher-level code since there is no
longer any need to worry about whether or not the flash subsystem has
been initialized. It would also give some code size savings in the
flash subsystem, and in the medium to long term it would allow other
subsystems such as fconfig to be statically initialized as well.
However, after experimenting with various different patches, I have
come to the conclusion that this is not the right time to make the
change. It is not too bad when there is only a single flash device and
everything works, but if there are initialization problems then things
I need more detail than "get messy". This is what the dev->init member is
meant to be for. Uninitialised devices get subsequently ignored, and the
return value of cyg_flash_init is irrelevant.
As with the spec for CYGBLD_GLOBAL_WARNINGS, you seem to be unilaterally
moving the goalposts from what had previously been agreed *extremely* late
in the day.
So instead of making the change now, for all anoncvs
targets and with no possiblity of testing on most of those targets, I
want to do the work in eCosPro first. It can then be merged into a
future anoncvs release, once I am confident that it is not going to
Why can it not be in both? Why should eCosPro be special with respect to a
changing API? And incompatible.
I don't know whether to wear an eCosCentric hat which says that eCosPro
should be aimed at well tested code, rather that a testbed for allegedly
unstable new code; or wear a maintainer hat and say that what happens in
eCosPro is not relevant to the public project, and API incompatibilities
made in such a way as to place eCosPro as "more advanced" is not a
principle to be encouraged.
2) the specification of cyg_flash_init(), i.e. whether or not it
takes a printf() function as argument, is not actually important.
cyg_flash_init() will become deprecated, and mostly a no-op, when
the flash subsystem switches to using a prioritized constructor.
It does not actually matter if a deprecated function takes a
function pointer as argument.
But you've completely omitted how to properly set the printf function.
That means there are no long-term API concerns either. There are
functions to be added to the API, but those can wait till later.
I disagree. This means we are issuing an API which we have to instantly
deprecate and anyone presently coding to that API will encounter breakage
If the API is wrong we need to fix out before we make a major release. A
stable flash API was the second most critical change to make for eCos 3.0
after the header updates. We can't flub it. This is a problem I raised
with you back in 2006.
Let me know what you consider the problems to be and I will deal with them.
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