[PATCH] D30785: [DWARF] Versioning for DWARF constants; verify FORMs

[Adrian Prantl via llvm-commits]

> On Apr 20, 2017, at 10:20 AM, David Blaikie <dblaikie at gmail.com> wrote:
> 
> Also, Adrian - still curious to hear if you have any thoughts about /where/ that check should go (see the review history discussing failing when the attribute is added, rather than later when the abbreviation is created) as well as how it should be implemented (assert V report fatal, etc)

IIUC the main concern about putting it into the Abbreviation creation is that it might be expensive to get at the DWARF version of the CU.  I'm not sure how expensive it is going to be, but if this is in an !NDEBUG path only, perhaps the extra cost can be justified. That said, if it turns out to add a noticeable delay to our RA stage2 bots, then the code as it is in this review now is the right trade-off.

-- adrian