bash-4.2$ ./dc p 2.122e-313 (on my x86 machine) Attempting to print the last value off a non-existent stack should probably error, just like a pop(). My trivial fix is here: https://github.com/bifferos/bb/commit/4a06b0e0541a7049c4b4dc93c252c4d988af1b21 regards, Biff.