When a constant was negative internally, it was output with the sign included. The code was not prepared to handle this, and could therefore cause double minus signs. For example, -2147483648 was output as --2147483648, and -4294967296 was output as --1.
Fixed by adding a space for floats, and by translating the number to the range 2147483648..4294967295 for integers (hex would have worked just as well).