On 8/30/2013 12:04 AM, Chris Bannister wrote:
On Thu, Aug 29, 2013 at 09:25:31AM -0400, Jerry Stuckle wrote:The problem with changing upstream code is it is not a one-shot deal. Changes must be investigated and applied every time a new version comes out, which means someone has to keep track of the changes which were done, and see how they fit into the new code. It can be a very time-consuming job.Doesn't Quilt alleviate a lot of the trouble?
Not really. It can manage the source code changes - but it is very superficial. It cannot determine the effects of those changes. What happens, for instance, when a routine is changed such that the code being executed is now conditional? Or it was conditional but no longer is? What happens if a function being called is no longer there (this one, at least, will give a compile error). Or even a variable changing from unsigned int to int (or vice versa)?
When working with production systems, you need to carefully examine how your patch affects the code, any time a new release comes out. It is time consuming and no one has yet invented a machine which can do it - not even "Watson" :).
Jerry