> I don't see what advantage this gives

I believe it may "just" be faster link times. Which may seem minor, but link times can often dominate incremental compile times because it's a slow and (at least historically) serial step which is O(total code size) even if the actual compilation is incremental.

See mold's linking benchmarks: https://github.com/rui314/mold. It can be the difference between multiple 10s of seconds with traditional linkers vs <2s with newers ones.

There are few strategies for dealing with this:

1. Is just to use a faster multi-threaded linker. On Linux, lld, mold, and wild on Linux are all much faster than the traditional ld/gold (and the latter two another step above lld). On macOS, the new built-in ld64 is pretty good. Not sure what the state is on Windows: possibly lld is best?

2. Is dynamic linking as above. This seems to be faster even though the dynamic links need to resolved at runtime. I presume because at least the links wholly within the dynlib don't need to be resolved.

3. Is tools like Subsecond (https://github.com/DioxusLabs/dioxus/tree/main/packages/subs...) which effectively implement incremental linking by diffing the symbols in object files.