[Lldb-commits] [PATCH] D129166: [lldb] Make sure we use the libc++ from the build dir

Wed Jul 6 09:45:23 PDT 2022

labath added a comment.

In D129166#3633116 <https://reviews.llvm.org/D129166#3633116>, @JDevlieghere wrote:

> Thanks for the thoughtful reply Pavel. The remote tests are something we care about as well, so I'd like to have a solution for that. What do you think about adding a "stdlib" mode to dotest.py which allows you to pick between "system libc++", "system libstdc++" and "just built libc++". The latter would be hermetic, and the former would match what we do today.

Well.. I think that specifying some of this explicitly would be great, but I don't think a choice between a libc++ and libstdc++ makes sense.

The way I see it, we have three kinds of tests:

1. Tests which don't care which library we use. This is the vast majority of them. The only need it to be there, but the actual test result should not depend on the library used in any way. For these tests, we can use any library we like. (except maybe for the gmodules test variant, but I don't actually know how that one works). I don't think we need to offer a choice here. Ideally we would be able to just pick the option that works (it may not be the same option for each config).
2. Tests which explicitly require libc++. There shouldn't be too many of these, and ideally these would be limited to tests for the libc++ pretty printers and such. It doesn't make sense to run these against libstdc++. In fact, that would be harmful, because it might actually work, but test the wrong thing. Ideally, we'd give the user the option to choose between the system libc++, just-built libc++ or a way to specify the arguments needed to build&run these kinds of executables.
3. Tests which explicitly require libstdc++. These is the same thing, except for libstdc++ pretty printers. And that we obviously don't have an in-tree version of libstdc++. And I don't think we have many people interested in running tests against libstdc++, so we probably don't have to go overboard on this one, but it would be nice to be able to keep running the existing tests against system libstdc++ on systems which have one.

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  https://reviews.llvm.org/D129166/new/

https://reviews.llvm.org/D129166