[cfe-dev] david's integer overflow stuff

[Chris Lattner]

On Sep 10, 2010, at 3:33 PM, David Chisnall wrote:
>> In any case, I don't think that there is any reasonable discussion to be had: it's the wrong thing to do for -ftrapv, as I said before, it breaks an established model.  
> 
> What established model?  Every time -ftrapv is mentioned on the GCC lists, the instructions are not to use it.  

-ftrapv is documented in the GCC manual and the GCC man pages.  The documentation does not say that an additional function need be linked into the program.

>>>> I didn't realize that you were implementing it in a gcc compatible way.
>>> 
>>> I provided a default handler function that would call abort (after printing a helpful error) along with the original patch.  It never got committed (I didn't have commit access back then, other people were committing my patches).  Mike said it would go in a clang runtime lib when one existed.
>> 
>> Are you sure that I approved the patch and not mike?  Do you have a link?
> 
> Mike committed it.  You reviewed it and asked that the -ftrapu option be removed.  Check the mailing list archives for April 2, 2009.  We also discussed it in IRC, where I explained both the implementation and my use of it in some detail (if you log private chats, check around April 2-4, 2009 - I don't keep logs).

Alright, well I don't remember that it was implementing something that was incompatible with -ftrapv.

I'm sorry for the confusion on this, I really thought that I emailed you about it.

-Chris