has c++ ever been a strict superset of c?

afaik,

  int* arr = malloc(sizeof(int));

has never worked in c++.

It's probably never been a strict superset really.

To use a trivial example:

    int free;

care to explain which language this doesn't work in (and why)? I'm curious. AFAIK, `free` isn't a keyword in either language and this is just declaring an int variable with a legal identifier (but not initializing it).