On 10/4/19 8:23 PM, Indu Bhagat wrote: > Hello, > > At GNU Tools Cauldron this year, some folks were curious to know more on how > the "type representation" in CTF compares vis-a-vis DWARF.
I was one of those, and I brought this up to Jose, after your presentation. Glad to see the follow up! Thanks much for this. In your Cauldron presentation we saw CTF compared to full blown DWARF as justification for CTF, but I was more interested in a comparison between CTF and a DWARF subset containing exactly only what you have available in CTF. Because if DWARF with everything-you-don't-need stripped out is in the same ballpark, then I am puzzled on why add/maintain a new Debug format, with all the duplication of effort that entails going forward. Also, it's my understanding that the current CTF format doesn't yet support C++, Vector registers, etc., maybe other things, so if DWARF was sufficient for your needs, then in the long run it sounds like a better option to me, as then you wouldn't have to extend CTF _and_ DWARF whenever some feature is needed. Maybe it would make sense to work on integrating CTF into the DWARF standard itself, not sure? I was also curious on your plans for adding unwinding support to CTF, while the kernel (the main CTF user, IIUC), already has plans to use its own unwinding format (ORC)? So with all those questions, I came out of the presentation thinking that I could not really justify CTF if I were asked to. (Side note: the Cauldron page is missing slides for your presentation, so I couldn't go and recheck some things mentioned above.) Thanks, Pedro Alves
