runtime demangler API

[Alex Samuel]

There's something somewhat confusing about the runtime API to the
demangler (abi::__cxa_demangle).  Presumably, the main use of this
function will be to mangle type names from typeinfo structures.  Note
that these aren't quite proper mangled names according to the grammar,
i.e. not productions of <mangled-name>, but rather productions of
<type>.  Particularly, they don't start with _Z.

This leaves open the confusion that, for instance, if I call
__cxa_demangle with the input "i", do I mean the function/variable
`extern "C" i' or the type `int'? 

Does anyone anticipate that this will be a problem?  In any case, the
specification should probably address what the correct behaviour here
is.

Regards
Alex Samuel
CodeSourcery LLC