in file src/BulletDynamicsWorld/ibmsdk/Makefile
OBJS = \
btConeTwistConstraint.o \ //this object missed in makefile
btContactConstraint.o \
btGeneric6DofConstraint.o \
btHingeConstraint.o \
btPoint2PointConstraint.o \
btSequentialImpulseConstraintSolver.o \
btSolve2LinearConstraint.o \
btTypedConstraint.o \
btDiscreteDynamicsWorld.o \
btRigidBody.o \
btSimpleDynamicsWorld.o \
btRaycastVehicle.o \
btWheelInfo.o