What is "addresssanitizer"

AddressSanitizer (or ASan) is a programming tool that detects memory corruption bugs such as buffer overflows or accesses to a dangling pointer (use-after-free). AddressSanitizer is based on compiler instrumentation and directly-mapped shadow memory. AddressSanitizer is currently implemented in Clang (starting from version 3.1) and GCC (starting from version 4.8). On average, the instrumentation increases processing time by about 73% and memory usage by 340%.