compiler linkage warning

I don't quite understand with respect to the documentations on linkage compatibility business as shown in the compiler message below:

Code:

1>e:\test\installer\prninst.h(159) : warning C4190: 'ObtainPrinterDriverDirectory' has C-linkage specified, but returns UDT 'std::basic_string<_Elem,_Traits,_Ax>' which is incompatible with C
1>        with
1>        [
1>            _Elem=wchar_t,
1>            _Traits=std::char_traits<wchar_t>,
1>            _Ax=std::allocator<wchar_t>
1>        ]

I found a prospective problem that's associated with this warning could be that I'm using a string object inside a user-defined struct. Is it legal in the language to declare a string inside a struct?

The function is marked as "C", but your are using C++ code inside it. That's why it warns you.

Originally Posted by stanlvw

Is it legal in the language to declare a string inside a struct?

Yes, that's fine. Elysia is right; what's probably goinig on is that your header contains

Code:

extern "C"

yet the function is returning a C++ type.

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Computer Programming: An Introduction for the Scientifically Inclined