I'm trying to compile LambdaMOO 1.7.8p4 under Linux 1.3.15 and with gcc 2.6.3 and I get: numbers.o: In function 'bf_sqrt': /usr/local/bin/MOO-1.7.8p4/numbers.c:186: undefined reference to 'sqrt' make: *** [moo] Error 1 rm parser.c Anybody know how I can get around this?