Solved. I have included all the libraries. The problem was in calling the getTouch function. I declared x,y,z as variables of type unsigned short and called the getTouch with x,y,z as parameters. The compilation was successful and the getTouch returns true on touching the screen and fills in the x,y,z values.
I am working on the Tiva C Launchpad with Energia. The BoosterPack I am using is the Kentec graphic display with SPI (BOOSTXL-K350VG-S1).As discussed earlier in the forum, I have removed resistor R10 on the Launchpad. My Energia version is 1.6.10E18. With the inbuilt library for Kentec, the graphics and text functions are working fine. But the Touch function, getTouch fails to compile, throwing up the error 'No matching function for call to 'Screen_K35_SPI::getTouch(uint16_t*,uint16_t*,uint16_t*). Can any one help out?