Lightmap UV generated on Windows and Mac is not deterministic

1. Download the SM_BLD_Plant_Hangar_Outbuilding_01.uasset and copy it to a simple project in UE5.3/4/5
2. Open the static mesh and observe the Lightmap UV on Windows and Mac

The Lightmap UV is not the same; please see the screenshots of LightmapUV_Mac and LightmapUV_Windows in the attachment.

I found out that it's because of the float precision differences between Windows and Mac; it uses /fp:fast on the Windows compiler, and it uses Clang, which should be precise on the Mac. I tried to compile the UEEditor with /fp:precise on Windows, and it became the same.