Ada Programming/Libraries/Ada.Synchronous Barriers

is a unit of the Predefined Language Environment since Ada 2012.

Specification
PreelaborateSynchronous_Barriers Barrier_Limit Positive  1  implementation_defined Synchronous_Barrier Release_Threshold Barrier_Limit Wait_For_Release The_Barrier   Synchronous_Barrier Notified        Boolean AdaSynchronous_Barriers

Wikibook

 * Ada Programming/Libraries/Ada