Warning for empty variables

2012-02-15 21:57:38 Warning: Warning (2): Invalid argument supplied for foreach() in [/Applications/MAMP/htdocs/gears/trunk/app/Model/Cou.php, line 147]
Trace:
Cou::childCous() - APP/Model/Cou.php, line 147
AppController::calculateCMRoles() - APP/Controller/AppController.php, line 229
CoNsfDemographicsController::isAuthorized() - APP/Controller/CoNsfDemographicsController.php, line 198
ControllerAuthorize::authorize() - CORE/Cake/Controller/Component/Auth/controllerAuthorize.php, line 64
AuthComponent::isAuthorized() - CORE/Cake/Controller/Component/AuthComponent.php, line 379
AuthComponent::startup() - CORE/Cake/Controller/Component/AuthComponent.php, line 330
ObjectCollection::trigger() - CORE/Cake/Utility/ObjectCollection.php, line 104
Controller::startupProcess() - CORE/Cake/Controller/Controller.php, line 606
Dispatcher::_invoke() - CORE/Cake/Routing/Dispatcher.php, line 101
Dispatcher::dispatch() - CORE/Cake/Routing/Dispatcher.php, line 86
[main] - APP/webroot/index.php, line 96

2012-02-15 21:59:40 Warning: Warning (2): array_merge() [<a href='function.array-merge'>function.array-merge</a>]: Argument #2 is not an array in [/Applications/MAMP/htdocs/gears/trunk/app/Model/Cou.php, line 154]
Trace:
array_merge - [internal], line ??
Cou::childCous() - APP/Model/Cou.php, line 154
AppController::calculateCMRoles() - APP/Controller/AppController.php, line 229
CoNsfDemographicsController::isAuthorized() - APP/Controller/CoNsfDemographicsController.php, line 198
ControllerAuthorize::authorize() - CORE/Cake/Controller/Component/Auth/controllerAuthorize.php, line 64
AuthComponent::isAuthorized() - CORE/Cake/Controller/Component/AuthComponent.php, line 379
AuthComponent::startup() - CORE/Cake/Controller/Component/AuthComponent.php, line 330
ObjectCollection::trigger() - CORE/Cake/Utility/ObjectCollection.php, line 104
Controller::startupProcess() - CORE/Cake/Controller/Controller.php, line 606
Dispatcher::_invoke() - CORE/Cake/Routing/Dispatcher.php, line 101
Dispatcher::dispatch() - CORE/Cake/Routing/Dispatcher.php, line 86
[main] - APP/webroot/index.php, line 96

2012-02-15 21:59:40 Warning: Warning (2): sort() expects parameter 1 to be array, null given in [/Applications/MAMP/htdocs/gears/trunk/app/Controller/AppController.php, line 230]
Trace:
sort - [internal], line ??
AppController::calculateCMRoles() - APP/Controller/AppController.php, line 230
CoNsfDemographicsController::isAuthorized() - APP/Controller/CoNsfDemographicsController.php, line 198
ControllerAuthorize::authorize() - CORE/Cake/Controller/Component/Auth/controllerAuthorize.php, line 64
AuthComponent::isAuthorized() - CORE/Cake/Controller/Component/AuthComponent.php, line 379
AuthComponent::startup() - CORE/Cake/Controller/Component/AuthComponent.php, line 330
ObjectCollection::trigger() - CORE/Cake/Utility/ObjectCollection.php, line 104
Controller::startupProcess() - CORE/Cake/Controller/Controller.php, line 606
Dispatcher::_invoke() - CORE/Cake/Routing/Dispatcher.php, line 101
Dispatcher::dispatch() - CORE/Cake/Routing/Dispatcher.php, line 86
[main] - APP/webroot/index.php, line 96

2012-02-15 21:59:40 Warning: Warning (2): array_merge() [<a href='http://php.net/function.array-merge'>function.array-merge</a>]: Argument #2 is not an array in [/Applications/MAMP/htdocs/gears/trunk/app/Model/Cou.php, line 154]
Trace:
array_merge - [internal], line ??
Cou::childCous() - APP/Model/Cou.php, line 154
AppController::calculateCMRoles() - APP/Controller/AppController.php, line 229
CoNsfDemographicsController::editSelf() - APP/Controller/CoNsfDemographicsController.php, line 154
ReflectionMethod::invokeArgs() - [internal], line ??
Controller::invokeAction() - CORE/Cake/Controller/Controller.php, line 473
Dispatcher::_invoke() - CORE/Cake/Routing/Dispatcher.php, line 104
Dispatcher::dispatch() - CORE/Cake/Routing/Dispatcher.php, line 86
[main] - APP/webroot/index.php, line 96

2012-02-15 21:59:40 Warning: Warning (2): sort() expects parameter 1 to be array, null given in [/Applications/MAMP/htdocs/gears/trunk/app/Controller/AppController.php, line 230]
Trace:
sort - [internal], line ??
AppController::calculateCMRoles() - APP/Controller/AppController.php, line 230
CoNsfDemographicsController::editSelf() - APP/Controller/CoNsfDemographicsController.php, line 154
ReflectionMethod::invokeArgs() - [internal], line ??
Controller::invokeAction() - CORE/Cake/Controller/Controller.php, line 473
Dispatcher::_invoke() - CORE/Cake/Routing/Dispatcher.php, line 104
Dispatcher::dispatch() - CORE/Cake/Routing/Dispatcher.php, line 86
[main] - APP/webroot/index.php, line 96

2012-02-15 21:59:40 Warning: Warning (2): array_merge() [<a href='function.array-merge'>function.array-merge</a>]: Argument #2 is not an array in [/Applications/MAMP/htdocs/gears/trunk/app/Model/Cou.php, line 154]
Trace:
array_merge - [internal], line ??
Cou::childCous() - APP/Model/Cou.php, line 154
AppController::calculateCMRoles() - APP/Controller/AppController.php, line 229
CoNsfDemographicsController::isAuthorized() - APP/Controller/CoNsfDemographicsController.php, line 198
ControllerAuthorize::authorize() - CORE/Cake/Controller/Component/Auth/controllerAuthorize.php, line 64
AuthComponent::isAuthorized() - CORE/Cake/Controller/Component/AuthComponent.php, line 379
AuthComponent::startup() - CORE/Cake/Controller/Component/AuthComponent.php, line 330
ObjectCollection::trigger() - CORE/Cake/Utility/ObjectCollection.php, line 104
Controller::startupProcess() - CORE/Cake/Controller/Controller.php, line 606
Dispatcher::_invoke() - CORE/Cake/Routing/Dispatcher.php, line 101
Dispatcher::dispatch() - CORE/Cake/Routing/Dispatcher.php, line 86
[main] - APP/webroot/index.php, line 96

2012-02-15 21:59:40 Warning: Warning (2): sort() expects parameter 1 to be array, null given in [/Applications/MAMP/htdocs/gears/trunk/app/Controller/AppController.php, line 230]
Trace:
sort - [internal], line ??
AppController::calculateCMRoles() - APP/Controller/AppController.php, line 230
CoNsfDemographicsController::isAuthorized() - APP/Controller/CoNsfDemographicsController.php, line 198
ControllerAuthorize::authorize() - CORE/Cake/Controller/Component/Auth/controllerAuthorize.php, line 64
AuthComponent::isAuthorized() - CORE/Cake/Controller/Component/AuthComponent.php, line 379
AuthComponent::startup() - CORE/Cake/Controller/Component/AuthComponent.php, line 330
ObjectCollection::trigger() - CORE/Cake/Utility/ObjectCollection.php, line 104
Controller::startupProcess() - CORE/Cake/Controller/Controller.php, line 606
Dispatcher::_invoke() - CORE/Cake/Routing/Dispatcher.php, line 101
Dispatcher::dispatch() - CORE/Cake/Routing/Dispatcher.php, line 86
[main] - APP/webroot/index.php, line 96