A method, apparatus, and computer instructions for generating coverage data for accesses to dynamically allocated data during execution of code in a data processing system. In response to a request to dynamically allocate a memory area for dynamically allocated data, the memory area is dynamically allocated during execution of the code. The memory area is associated with a data access indicator in response to dynamically allocating this memory area. A determination is made as to whether an access to a memory location associated with the data access indicator has occurred, in response to executing an instruction in the code at a processor in the data processing system. If the data access indicator is associated with the memory area, a state of the data access indicator by the processor is changed when the instruction is executed. The coverage data for the dynamically allocated data is generated during execution of the code by the processor.