$ clang foo.c -g -fsanitize=address -fno-omit-frame-pointer $ ./a.out ================================================================= ==47384==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7fff5ad0c745 at pc 0x000104ef3d98 bp 0x7fff5ad0c710 sp 0x7fff5ad0c708 WRITE of size 1 at 0x7fff5ad0c745 thread T0 #0 0x104ef3d97 in main foo.c:6 #1 0x7fff9a7745ac in start (/usr/lib/system/libdyl