Nullptr checks on cl kernels on deinit

Author: amikhail48

targets/opencl/vx_interface.cpp

@@ -398,16 +398,20 @@ extern "C" vx_status vxTargetDeinit(vx_target target)
                 if (target->kernels[k])
                 {
                     target->kernels[k]->decrementReference(VX_INTERNAL);
-                    clReleaseKernel(cl_kernels[k]->kernels[p]);
-                    clReleaseProgram(cl_kernels[k]->program[p]);
+                    if (cl_kernels[k]->kernels[p]) clReleaseKernel(cl_kernels[k]->kernels[p]);
+                    if (cl_kernels[k]->program[p]) clReleaseProgram(cl_kernels[k]->program[p]);
                 }
 
             }
             for (d = 0; d < context->num_devices[p]; d++)
             {
-                clReleaseCommandQueue(context->queues[p][d]);
+                if (context->queues[p][d])
+                {
+                    clFinish(context->queues[p][d]);
+                    clReleaseCommandQueue(context->queues[p][d]);
+                }
             }
-            clReleaseContext(context->global[p]);
+            if (context->global[p]) clReleaseContext(context->global[p]);
         }
     }
     return VX_SUCCESS;