[clang] [serialization] no transitive decl change (PR #92083)

[David Spickett via cfe-commits]

DavidSpickett wrote:

> Thanks. Reproduced. But it surprised me that I can't run the commands you mentioned, but I need to run:
> ./bin/lldb-dotest -p TestTemplateWithSameArg.py -G gmodules

Running the tests as modules is perhaps opt in, we have the ability to run them with different debug info types too. So this is not surprising. Well, it is for you, but doesn't mean there's anything wrong here :)

> And I am also slightly surprised that after I change the code, it doesn't work if I run ninja lldb-test only I need to run ninja clang lldb. Do I misconfigure anything? I build lldb by:

My comment about `lld-test` referred to a different failing test I think (and if we did have some dependencies incorrect, it wouldn't surprise me). Nothing wrong with that config line though.

So good news is Linux and Windows lldb are ok (Mac will report back soon I assume), but now we have failures on 32 bit Arm builds:
https://lab.llvm.org/buildbot/#/builders/245/builds/25498

I'm going to reproduce this shortly but my bet is that this is undefined behaviour of some kind. It may not be due to your code but your code may be exposing a pre-existing issue.

https://github.com/llvm/llvm-project/pull/92083