Trying to use an Integrator for multiple Contexts produces an exception

platforms/reference/tests/TestReferenceCustomAngleForce.cpp

@@ -79,7 +79,6 @@ void testAngles() {
     harmonicSystem.addParticle(1.0);
     harmonicSystem.addParticle(1.0);
     harmonicSystem.addParticle(1.0);
-    VerletIntegrator integrator(0.01);
     HarmonicAngleForce* harmonic = new HarmonicAngleForce();
     harmonic->addAngle(0, 1, 2, 1.5, 0.8);
     harmonic->addAngle(1, 2, 3, 2.0, 0.5);
@@ -91,9 +90,9 @@ void testAngles() {
     init_gen_rand(0, sfmt);
 
     vector<Vec3> positions(4);
-    VerletIntegrator integrator1(0.01);
-    VerletIntegrator integrator2(0.01);
     for (int i = 0; i < 10; i++) {
+        VerletIntegrator integrator1(0.01);
+        VerletIntegrator integrator2(0.01);
         Context c1(customSystem, integrator1, platform);
         Context c2(harmonicSystem, integrator2, platform);
         for (int j = 0; j < (int) positions.size(); j++)

platforms/reference/tests/TestReferenceCustomHbondForce.cpp

@@ -109,9 +109,9 @@ void testHbond() {
     init_gen_rand(0, sfmt);
 
     vector<Vec3> positions(5);
-    VerletIntegrator integrator1(0.01);
-    VerletIntegrator integrator2(0.01);
     for (int i = 0; i < 10; i++) {
+        VerletIntegrator integrator1(0.01);
+        VerletIntegrator integrator2(0.01);
         Context c1(customSystem, integrator1, platform);
         Context c2(standardSystem, integrator2, platform);
         for (int j = 0; j < (int) positions.size(); j++)

plugins/freeEnergy/platforms/cuda/tests/TestCudaGBVISoftcoreForce.cpp

@@ -177,7 +177,6 @@ void testEnergyEthaneSwitchingFunction( int useSwitchingFunction ) {
     for( int i = 0; i < numParticles; i++ ){
        system.addParticle(1.0);
     }
-    LangevinIntegrator integrator(0, 0.1, 0.01);
 
     double C_HBondDistance   = 0.1097;
     double C_CBondDistance   = 0.1504;
@@ -282,8 +281,10 @@ void testEnergyEthaneSwitchingFunction( int useSwitchingFunction ) {
 
     system.addForce(nonbonded);
 
-    Context referenceContext(system, integrator, referencePlatform);
-    Context context(system, integrator, platform);
+    LangevinIntegrator integrator1(0, 0.1, 0.01);
+    LangevinIntegrator integrator2(0, 0.1, 0.01);
+    Context referenceContext(system, integrator1, referencePlatform);
+    Context context(system, integrator2, platform);
     
     vector<Vec3> positions(numParticles);
     positions[0] = Vec3(0.5480,    1.7661,    0.0000);