Experimental Physics and
Industrial Control System

Mark Rivers via Tech-talk <[email protected]> · Thu, 9 Jan 2020 21:38:14 +0000

Hi Lewis,

I am trying to understand your motivation in pushing for ABI compatibility.  Can you please explain clearly how you will use this, and how you think it will save you time and effort?

As far as I know you are responsible for the control system on a single beamline with a single experimental station.  How much time do you estimate you will save by being able to upgrade EPICS with binary modules, rather than just building base and synApps from source?

I run 4 beamlines with 5 experimental stations, and the build and deploy process does not take much of my time.

Mark

-----Original Message-----
From: Tech-talk <[email protected]> On Behalf Of J. Lewis Muir via Tech-talk
Sent: Thursday, January 9, 2020 2:47 PM
To: Michael Davidsaver <[email protected]>
Cc: [email protected]
Subject: Re: EPICS release series after 7.0: 7.1 or 8.0? (ABI)

On 01/09, Michael Davidsaver wrote:
> The question has never been if it were possible, but rather who would 
> do this work for Base?

Please remember that any ABI compatibility would start at some future point in time of everyone's choosing.  No one has to go through the commit history and retroactively determine what has broken ABI compatibility.

And the idea is that the work would be shared and be done as development happens.  Developers would agree to not break ABI compatibility for changes intended for a certain branch of development.  They can do this by being aware of the rules for changes that will prevent breaking ABI compatibility, and tools can catch any mistakes.

> Thus my challenge (which you have chosen not to quote)
> 
> > Please identify all ABI changes made between 3.14.12.7 and 3.14.12.8 
> > and note those which are "incompatible".

I'm not interested in the challenge.  You're free to voice your opinion that it's a bad idea, although I would wish for you to be more specific about why you think it's a bad idea, and you're free to vote against it if it ever comes to a vote.

Lewis

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System