Starting from the version 093, the GMP version of cddlib, libcddgmp.a, contains all cdd library functions in two arithmetics. All functions with the standard prefix dd_ are computed with the GMP rational arithmetics as before. The same fuctions with the new prefix ddf_ are now added to the library libcddgmp.a that are based on the C double floating-point arithmetics. Thus these functions are equivalent to libcdd.a functions, except that all functions and variable types are with prefix ddf_ and the variable type mytype is replaced by myfloat.
In this sense, libcdd.a is a proper subset of libcddgmp.a and in principle one can do everything with libcddgmp.a. See how the new dd_LPSolve is written in cddlp.c.