The gsm library has been tested successfully on the following platforms:

- Various Sun4's running SunOS 4.1.2
- SPARC1 (SunOS 4.1.1)
- Integrated Solutions 68k Optimum running 4.3BSD UNIX with a Green Hills cc
- NeXTstation running NeXT-OS/Mach 3.0
- No-name AT/386 with Xenix 2.3.2 (using -DSTUPID_COMPILER)
- RS/6000-350 running AIX 3.2.0
- RS/6000-320 running AIX 3.1.5
- Alliant FX80 (Concentrix 5.7)
- SGI Indigo XS4000 (IRIX 4.0.5F)