FWIW, I compiled predict last night under Leopard (OSX 10.5) on my vanilla Core 2 iMac without difficulty. I have the usual developer stuff that comes with the OS, plus the iPhone SDK and all the goodies that go with it.
I deleted the include of sys/soundcard.h in installer.c, which produced a message about it being a bummer that I didn't have a sound card. Everything else worked, and it ran and generated predictions without comment. No issues with ftime(), no need to specify any additional libraries. I didn't try any of the support utilities.
The GNU-ish way to make programs and their compilation portable is automake and autoconf.
Laura Halliday VE7LDH "Que les nuages soient notre Grid: CN89mg pied a terre..." ICBM: 49 16.05 N 122 56.92 W - Hospital/Shafte _________________________________________________________________