[libcxx-commits] [libcxx] [libc++] Reenable codecvt in the dylib. (PR #73679)

[Louis Dionne via libcxx-commits]

ldionne wrote:

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> Ah, it is still related, see the test failure message.
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> @petrhosek and I discussed about the reason why this Fuchsia unrelated breakage wasn't caught by the upstream libcxx bots. It is likely due to the toolchain used when building libcxx and runtimes.
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> In our case, we always use a relatively recent clang we built to build the ToT clang. The ToT clang will then be used to build the runtime.
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> In upstream llvm bots, for runtime builds, it usually uses a last stable release clang to build the ToT runtime directly to reduce build time. In this case, the bug like this won't be caught until there is a new llvm stable release. I think for libcxx, at least there should be a few bots configured in a way that bots need to use ToT clang to build libcxx and corresponding runtimes for the host platform. Otherwise, breakage like this will be hide in dark.

We do have a bot that runs all of our tests against a just-built Clang using the bootstrapping build, which should catch that.

https://github.com/llvm/llvm-project/pull/73679