ElectricFence is a utility for C programming and debugging. ElectricFence uses the virtual memory hardware of your system to detect when software overruns malloc() buffer boundaries, and/or to detect any accesses of memory released by free(). ElectricFence will then stop the program on the first instruction that caused a bounds violation and you can use your favorite debugger to display the offending statement.

Install ElectricFence if you need a debugger to find malloc() violations.