Arduino and Adafruit motor shield V2 problem...

Hi....I'm trying to make a Simulink Library module for the Adafruit Motorshield v2.0 with S-function builder to work with an arduino card. When i try to implement the "application" i get this error (see after this text) "undefined reference to..." and i can't understand what is wrong...Can you help me ? thanks.

C:/ProgramData/MATLAB/SupportPackages/R2017b/3P.instrset/arduinoide.instrset/arduino-1.8.1/hardware/tools/avr/bin/avr-gcc -w -Os -Wl,--gc-sections,--relax -mmcu=atmega328p -o ../adafruitmsi2d.elf adafruitmsi2d.o sfADAFMSI2C_wrapper.o wiring_pulse.S.o hooks.o WInterrupts.o wiring.o wiring_analog.o wiring_digital.o wiring_pulse.o wiring_shift.o abi.o CDC.o HardwareSerial.o HardwareSerial0.o HardwareSerial1.o HardwareSerial2.o HardwareSerial3.o PluggableUSB.o IPAddress.o new.o Print.o Stream.o Tone.o USBCore.o WMath.o WString.o MW_ArduinoHWInit.o io_wrappers.o arduinoAVRScheduler.o ert_main.o -lm sfADAFMSI2C_wrapper.o: In function `Adafruit_MotorShield::setPin(unsigned char, bool)': C:\Users\NOVAFLY-PI\Documents\MATLAB\LIBADAFRUIMSV2\adafruitmsi2d_ert_rtw/../Adafruit_MotorShield.cpp:477: undefined reference to `Adafruit_MS_PWMServoDriver::setPWM(unsigned char, unsigned int, unsigned int)' sfADAFMSI2C_wrapper.o: In function `Adafruit_MotorShield::begin(unsigned int, TwoWire*)': C:\Users\NOVAFLY-PI\Documents\MATLAB\LIBADAFRUIMSV2\adafruitmsi2d_ert_rtw/../Adafruit_MotorShield.cpp:82: undefined reference to `Adafruit_MS_PWMServoDriver::begin()' C:\Users\NOVAFLY-PI\Documents\MATLAB\LIBADAFRUIMSV2\adafruitmsi2d_ert_rtw/../Adafruit_MotorShield.cpp:84: undefined reference to `Adafruit_MS_PWMServoDriver::setPWMFreq(float)' C:\Users\NOVAFLY-PI\Documents\MATLAB\LIBADAFRUIMSV2\adafruitmsi2d_ert_rtw/../Adafruit_MotorShield.cpp:86: undefined reference to `Adafruit_MS_PWMServoDriver::setPWM(unsigned char, unsigned int, unsigned int)' sfADAFMSI2C_wrapper.o: In function `Adafruit_MotorShield::setPWM(unsigned char, unsigned int)': C:\Users\NOVAFLY-PI\Documents\MATLAB\LIBADAFRUIMSV2\adafruitmsi2d_ert_rtw/../Adafruit_MotorShield.cpp:101: undefined reference to `Adafruit_MS_PWMServoDriver::setPWM(unsigned char, unsigned int, unsigned int)' sfADAFMSI2C_wrapper.o: In function `Adafruit_MotorShield::setPin(unsigned char, bool)': C:\Users\NOVAFLY-PI\Documents\MATLAB\LIBADAFRUIMSV2\adafruitmsi2d_ert_rtw/../Adafruit_MotorShield.cpp:115: undefined reference to `Adafruit_MS_PWMServoDriver::setPWM(unsigned char, unsigned int, unsigned int)' sfADAFMSI2C_wrapper.o: In function `Adafruit_MotorShield::Adafruit_MotorShield(unsigned char)': C:\Users\NOVAFLY-PI\Documents\MATLAB\LIBADAFRUIMSV2\adafruitmsi2d_ert_rtw/../Adafruit_MotorShield.cpp:52: undefined reference to `Adafruit_MS_PWMServoDriver::Adafruit_MS_PWMServoDriver(unsigned char)' C:\Users\NOVAFLY-PI\Documents\MATLAB\LIBADAFRUIMSV2\adafruitmsi2d_ert_rtw/../Adafruit_MotorShield.cpp:54: undefined reference to `Adafruit_MS_PWMServoDriver::Adafruit_MS_PWMServoDriver(unsigned char)' collect2.exe: error: ld returned 1 exit status gmake: * [../adafruitmsi2d.elf] Error 1 C:\Users\NOVAFLY-PI\Documents\MATLAB\LIBADAFRUIMSV2\adafruitmsi2d_ert_rtw>echo The make command returned an error of 2 The make command returned an error of 2 C:\Users\NOVAFLY-PI\Documents\MATLAB\LIBADAFRUIMSV2\adafruitmsi2d_ert_rtw>An_error_occurred_during_the_call_to_make 'An_error_occurred_during_the_call_to_make' n'est pas reconnu en tant que commande interne ou externe, un programme exécutable ou un fichier de commandes. ### Creating HTML report file adafruitmsi2d_codegen_rpt.html ### Build procedure for model: 'adafruitmsi2d' aborted due to an error. Error:Error(s) encountered while building "adafruitmsi2d": ### Failed to generate all binary outputs.____