This is really moot since MSVCRT is a C runtime lib with MSVCPRT being the the C++ one. Again no stability guarantees are made with any of this. Microsoft pro

This is really moot since MSVCRT is a C runtime lib with MSVCPRT being the the C++ one. Again no stability guarantees are made with any of this. Microsoft promises backward compatibility but not forward compatibility. There is no promise you can link new code with old DLLs. Just that older binaries will still execute unmodified. Very recently with VS2015 they promised "some" forward compatibility and to make fewer changes. In practice there were things you could do to increase the chances of this working. But to call this "stable" would render the term meaningless.