Hi,
Do you always work on Primer2 platform ?
Because the "circle_platform" you are including is corresponding on the STM32L EvoPrimer platform, which include the ST librayr file "stm32l1xx.h".
Be careful, the directories to include into your project is depending on your target board (Primer1 or 2, EvoPrimer STM32E, STM32C, STM32L...), and some files have the same name, but are located in the corresponding folder.
Yves