extern TT_RetType Stm_Drv_ClearCompareFlag(STM_BitType * const stm, Stm_Comparator const comparator);

The function `Stm_Drv_ClearCompareFlag` seems to be a part of a driver for STM (System Timer) module. It takes two parameters:

1. `stm`: A pointer to a variable of type `STM_BitType`. It is likely used to access the STM module's register or flags.
2. `comparator`: A constant value of type `Stm_Comparator`. This parameter might represent the specific comparator whose compare flag needs to be cleared.

The return type of the function is `TT_RetType`, which is likely a custom-defined type for error handling or status indication.

Please note that without additional context or the implementation code, it is difficult to provide more specific information about the purpose and behavior of this function.