[cfe-dev] david's integer overflow stuff

[Chris Lattner]

>>> I've just committed some stuff (r114192) that restores the old behaviour of -ftrapv-handler= is specified.
>> 
>> David, please get significant changes like this reviewed before they are committed.
> 
> The change is a couple of dozen lines, most of which is in the option handling stuff, and the rest of it is restoring code that was in trunk for over a year - hardly a 'significant' change - and it restores functionality that we are had in the last two releases.

You're adding a major new feature to the compiler.  In addition to discussion of whether or not it is a good thing, it should be decided if it's the right way to solve the problem, and the patch should include documentation.  You've skipped all of this.  The previous behavior in the last two releases had the exact same problems.

I appreciate that the new approach is much more minimal, and I like the design much better than the old.  Please propose some documentation for it.  Also, why does the handler return a value instead of aborting?  I don't see how this is useful.

>>> Please can you take a look and make sure that it doesn't conflict with anything that you want to do.  
>>> 
>>> Chris: Is there any chance of merging this into the 2.8 branch - it would be nice if 2.8 didn't break stuff that worked with 2.7...
>> 
>> Absolutely not, the schedule is well past accepting new features.
> 
> So we're going to have to tell people to compile some files with 2.7 and the rest with 2.8.  Thanks, I'm sure that will make it much easier to persuade people to adopt clang.  

I don't see how this affects adoption.  If they haven't adopted it yet, then a change from 2.7->2.8 won't affect them.

-Chris