[dminik]

There's no custom rust linker just yet. The change in September was to switch from GNU LD to lld for performance on Linux. There are some rust linker projects (like wild), but these tend to be aimed at speed (and/by incremental linking) rather than executable size.

I'm not sure how useful deduplication at the linker level is in practice. Though I don't think Rust does anything different here than C++. The main issue I imagine is that the types used in generic code have different sizes and layouts. This seems to me like it would prevent deduplication for most functions.