2022.02
Extract to your home directory so the contents are in ~/mars. There should be just one "mars" folder.
GCC 10.3.0
SGDK 1.70
M68K + SH-2 compilers with Newlib
IMPORTANT NOTE ABOUT GCC 10.X:
GCC 10 sets -fno-common by default, which results in SGDK (and many of my own projects) to throw "multiple definition" errors during the linking stage. To work around this please add -fcommon to the CFLAGS in your Makefile.