System Workbench for STM32

undefined reference to `HAL_RTC_Init'

Using STemWin_HelloWorld of STM32Cube_FW_F4_V1.14.0 as Template and adding Support for
BME280 sensor works OK. Trying to use the internal RTC of the stm32f429 gives link error although
file stm32f4xx_hal_rtc.c compiles without error.

Ac6 Version:
OS: windows7 Ultimate
Board: stm32f429-discovery
Attached file: Console Output

Please help,