And apparently C++ isn't supported in the free-as-in-beer-and-code-size-limited editions, if that's what you have.
<rant> I once had the C++ compiler downgrade itself transparently to a C compiler because my network connection (with the license server behind it) was down, which resulted in hundreds of "Syntax error"s in header files clogging my problem view. </rant>
C++ support is available only in the Professional version of the tools. See this fact sheet for the details.
---Tom
Still, I wish the compiler error message said as much.