Defenses: Write Correct Code

• Never pass user data as the format argument. printf(user_input); /* NO */ printf("
• Enable compiler diagnostics:
• -Wformat —- checks format/argument type mismatches.
• -Wformat-security —- flags non-literal formats with no args.
• -Werror=format-security —- make it a hard build error.
• Static analyzers and code review specifically hunt the "non-literal format" pattern.