#include "common.h" #include int main(int argc, char** argv) { char buffer[8] = {0}; strncat(buffer, "1234567", 7); puts(buffer); /* n=1, buffer has 7 chars ("1234567"). * 7+1+1 = 9 > 8 → overflow. Even n=1 can overflow a nearly-full buffer. */ CHK_FAIL_START strncat(buffer, "X", 1); CHK_FAIL_END puts(buffer); return ret; }