1. A method of allocating memory to processing cores in a multi-core processing system, the system comprising: plural processing cores for performing processing tasks, each processing core processing each task allocated to that processing core to produce a result for that task; a buffer comprising an allocated amount of memory for storing results that are produced by the plural processing cores; and a task allocator that allocates to the processing cores tasks to be processed, the task allocator indicating to the processing cores memory portions in the buffer for storing the results produced for the tasks; the method comprising: the task allocator allocating to each processing core of the plural processing cores a respective set of tasks to be processed by that processing core, the task allocator also indicating to each processing core of the plural processing cores a respective particular memory portion in the buffer for storing the results produced by that processing core for its set of tasks; the method further comprising each processing core of the plural processing cores, when processing a particular task of the set of tasks to be processed by that processing core: (i) processing the particular task to produce a particular result for the particular task; (ii) storing the particular result in the respective particular memory portion of the allocated memory of the buffer indicated to the processing core by the task allocator; (iii) determining whether there is less than a threshold amount of memory remaining in the respective particular memory portion indicated to the processing core by the task allocator; and (iv) if there is less than the threshold amount of memory remaining in the respective particular memory portion indicated to the processing core by the task allocator, requesting the task allocator to indicate a new memory portion to the processing core; and the method further comprising the task allocator, in response to a new memory portion being requested by a particular processing core of the plural processing cores: indicating a new memory portion to the particular processing core.