[PATCH] D39558: [TargetParser][AArch64] Reorder enum to preserve 5.0.0 libLLVM ABI.

[Chad Rosier via Phabricator via llvm-commits]

mcrosier added a comment.

In https://reviews.llvm.org/D39558#914116, @javed.absar wrote:

> Would it make sense to add a test, so that any future changes doesn't undo this behaviour?


https://reviews.llvm.org/rL311659 (which reordered the enum in the first place) already has test coverage, however, I don't think that's the kind of testing you're suggesting.

I think what you're suggesting is that we add unit tests to ensure the enums don't get reordered.  AFAIK, we don't have a hard/fast rule for this (I could easily be mistaken).  IIUC the issue only arises when you want to backport a change so that, for example, the libLLVM.so shipped with the 5.0.0 release is compatible with the 5.0.1 release.  I don't know if we ensure major releases are compatible with this respect to one another.

Do you have any thoughts on this, Renato?


https://reviews.llvm.org/D39558