C++17 feature proposal: Ban std::any

[Daniel Cheng]

Similarly to absl::any, the no-RTTI implementation is incompatible with component builds: it uses the address of a static variable in a class that's templated on the type [1], but in a component build, different shared libraries will have their own copy of the static variable.

See https://crbug.com/1096380 for additional context.

Daniel

[1] https://github.com/llvm/llvm-project/blob/main/libcxx/include/any#L172

[K. Moon]

+1

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[Jeremy Roman]

+1 while the build issue exists.

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[Dan McArdle]

In case it needs to be said for anyone besides myself, note that std::any != std::any_of.

On Thu, Jan 6, 2022 at 4:18 PM K. Moon <km...@chromium.org> wrote:

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[Avi Drissman]

+1. Component builds are far more important.

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[Peter Kasting]

+1

PK

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