Yup, C++ has autocleanup. Of course if you are using fopen() instead something more modern you'll need to fclose(). Adding a new keywords to C is a long shot. Perhaps compilers could detect non-cleanup use of goto and give it a warning.
A typical C++ codebase I'm working on these days would have scope guards implemented via macros, such that you can do e.g.:
FILE* f = fopen(...);
SCOPE_GUARD({ fclose(f); });
With C++ you can ensure that you have your destructors do the tidy up, e.g. a messy example
struct cleaner { cleaner(string *toCleanup) : m_x(toCleanup) { } ~cleaner() { delete m_x; m_x = nullptr; } };