Background

Within the bevy project we're attempting to make as much of the engine compatible with no_std platforms as possible. One issue we've noticed is smol_str doesn't appear to support platforms without the full sync module (e.g., thumbv6m-none-eabi). We've worked around this issue using portable-atomic either directly or indirectly through our dependencies where required. Further details can be found here.

Request

Could smol_str be updated to support thumbv6m-none-eabi (and similar platforms) either by using portable-atomic, or some alternate approach?