Thread: Linker problem with template traits/policy on MSVS 2005

Hi everyone,

What compiles, links and runs perfectly on my home Linux station, compiled with GNU gxx-4. , does compile but not link with VisualStudio 2005.

The problem is that the linker apparently finds the copy constructor for my class Vector in the header Matrix.h too, but it just isn't there.
The same actually holds for ALL operators !

Voilà two of the error messages:

[cc] Vector.obj : error LNK2005: "public: __thiscall LinAlg::Vector<class LinAlg::Complex>::Vector<class LinAlg::Complex>(class LinAlg::Vector<class LinAlg::Complex> const &)" (??0?$Vector@VCom
plex@LinAlg@@@LinAlg@@QAE@ABV01@@Z) already defined in Matrix.obj
[cc] Vector.obj : error LNK2005: "public: class LinAlg::Vector<class LinAlg::Complex> & __thiscall LinAlg::Vector<class LinAlg::Complex>:: operator=(class LinAlg::Vector<class LinAlg::Complex> c
onst &)" (??4?$Vector@VComplex@LinAlg@@@LinAlg@@QAEAAV01@AB V01@@Z) already defined in Matrix.obj


Thanks a lot for your help!!!

Mark

Despite looking like it, 'template<> Vector<Complex> :: Vector( Vector<Complex> const&);' *1 is not a template. It is just a function. Specifically: it is a function in a header that is not declared 'inline'. Solve this problem the way you would, your preference, for any other such "problematic" function.

Edit: From what I can tell, MSVC has it right. I think 'LD' is just being a little to aggressive in ignoring multiple definitions for template functions.

Soma

*1:

Code:

template<> Vector<Complex> :: Vector( Vector<Complex> const&);

Despite looking like it, *1 is not a template

Yes, thanks for correcting my bad language.

Specifically: it is a function in a header that is not declared 'inline'.

So the problem is that it is in the header "Vector.h", which is included in "Matrix.h" ?
Ok, and then we use 'inline' to not include it twice?

Thanks!

O_o

Yes.

Soma