generic_once_cell is used at run time in 5 crates (of which 2 optionally). It is a direct run-time dependency in 3 crates.

Depender (with downloads and own rev deps) generic_once_cell version
7.8K 2 hermit-sync ^0.1
4.2K 3 mach-sys optional ^0.1.1
140 1 hermit optional ^0.1