[PATCH] D47969: [Verifier] Check that ValueAsMetadata belongs to the module

[Vlad Tsyrklevich via Phabricator via llvm-commits]

vlad.tsyrklevich added a comment.

Hi Roman, so I hit PR36785 while working on PR36784 which is a very similar bug triggered under certain conditions with LTO, you may want to take a look at that bug as well. It’s occurring for basically the exact same reason in another part of the code base, uniquing MD nodes leads to references across modules. In my case, my change to fix it (https://reviews.llvm.org/D47898) works around this because I took this (surprising) behavior to be expected, e.g. this review for a similar bug https://reviews.llvm.org/D26212 where the conclusion seemed to be that this behavior was expected—though that may be the wrong decision. Given that there’s been some history here and we’re taking slightly different approaches I think it’d be worth it to start a thread on llvm-dev to get some feedback on whether this behavior is allowable. Give me a day or so to take a look at ODR type uniquing in LTO and send that email.


Repository:
  rL LLVM

https://reviews.llvm.org/D47969