bnbarham added a comment. In D105328#2861028 <https://reviews.llvm.org/D105328#2861028>, @vsapsai wrote:
> This problem shouldn't happen based on module-level name hashing but for some > reason it is happening. If I'm not mistaken, InMemoryModuleCache uses .pcm > file name as the key. But that file name should contain a hash part that is > based on the modulemap path. But frameworks M in "frameworks" and > "frameworks2" should have different paths for modulemaps and should have > different .pcm names, therefore no conflicts in InMemoryModuleCache. Ah sorry, looks like I had my modules slightly confused. The underlying problem is that `B` is considered out of date due to the check on line 2920, ie. the one that creates the `err_imported_module_relocated` diagnostic. That causes `Top` to be re-compiled as a module it depends on is out of date. The location of `Top` hasn't changed, so it keeps the same .pcm path. `B` is also re-compiled, but as you point out that's perfectly fine since it'll get a different path in the cache. I'll update the comments in the test + the review summary. Sorry for the confusion. > I see the value in not crashing but looks like there might be a problem > somewhere else. For what it's worth, even if there was another cause I'd still like to get this change in - writing over a module in the cache causes all sorts of different crashes that are hard to diagnose. I'd be *very* surprised if there weren't more issues like this, so at least we'll get an actual error rather than random crashes. > Also it is more of my personal pet peeve. InMemoryModuleCache should simplify > memory management for modules but in practice it simplifies creating dangling > references. I'm not asking to address that, so if you feel like my requests > get too close to that direction, it's good to push back. Heh, I find this a nice summary of how I feel about it after trying to find the root cause of these crashes! Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D105328/new/ https://reviews.llvm.org/D105328 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
