[PATCH] D52952: [IR][Modules] Improve quality of diagnostic messages for non-fatal warnings during module linking.

[Kristina Brooks via Phabricator via llvm-commits]

kristina added a comment.

In https://reviews.llvm.org/D52952#1258114, @dblaikie wrote:

> Could this be tested with two .ll files with mismatched DWARF Versions, lto'd together like other LTO tests (in, for example, lld/test/ELF/lto/)


This would require introducing a category of tests for IR linker diagnostics, which currently do not exist, likely due to their relative insignificance and a somewhat (from my perspective, given how often modulemaps are forgotten and not updated and it not being noticed for a while) low number of module users overall, especially for projects outside of LLVM-related scope (and as I said, the actual diagnostics emitted and their validity/suitability have zero coverage, hence my remark about it being something for another time as it involves a fairly significant bulk of changes, if I understand it correctly). A regression in things like metadata naming on the other hand (like renaming `Dwarf Version` to something else) would be ABI breaking in terms of IR as well so if it does get renamed, a ton of other tests would fail as well.

This is just a quality-of-life improvement for dealing with migrating to DWARF5 as well as general migration of bitcode based builds forward over to LLVM 8 and finding stale bitcode archives easier for people who use modular builds involving linking against a variety of cached pre-built bitcode archives, which saves time when trying to work out which caches need purging.


Repository:
  rL LLVM

https://reviews.llvm.org/D52952