import libraries for Windows usually not needed, but 1) older cm3 releases contained bad ones, 2) some C toolsets are missing them
The core M3 library containing the complete runtime system.
m3-libs/m3core/src/unix/sysv-4.0/READMEThe standard M3 library containing all required interfaces (together with m3core). This library needs to be imported by almost any program.
m3-libs/libm3/src/sqrt/README