Overlap events in c++

Indeed, as said Steve, you are using 4.11 and from the log and the 4.11 source the overlap singature is
(AActor* OtherActor, UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult & SweepResult);

so you need to have :

         UFUNCTION()
             void OnOverlapBegin(AActor* OtherActor, UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult & SweepResult);

void AMyActor::OnOverlapBegin(AActor* OtherActor, UPrimitiveComponent* OtherComp, int32 OtherBodyIndex, bool bFromSweep, const FHitResult & SweepResult)