When compiling on Windows, the symbol NT must be defined either by a compiler option or in user source code before the xfft_v9_1_bitacc_cmodel.h header file is included.
Link to the import libraries libIp_xfft_v9_1_bitacc_cmodel.lib and libgmp.lib . For example, for Microsoft Visual Studio.NET, in Project Properties , under Linker > Input , for Additional Dependencies, specify libIp_xfft_v9_1_bitacc_cmodel.lib and libgmp.lib .