Re: Link Error

From:

"Alex Blekhman" <tkfx.N05P4M@yahoo.com>

Newsgroups:

microsoft.public.vc.language

Date:

Wed, 10 May 2006 13:28:02 +0300

Message-ID:

<#6IAtxBdGHA.1856@TK2MSFTNGP03.phx.gbl>

Alamelu wrote:

I am getting following link error.

A.obj : error LNK2019: unresolved external symbol
"__declspec(dllimport) public: static void __cdecl
Error::PError(class Error &,class Log const *,long)"
(__imp_?PError@ErrHan@@SAXAAVError@@PBVLog@@J@Z)
referenced in function $L218761

I checked the common possibility that could lead to link
error
a) Since it is static method i check if the method is
defined and found it to be defined.
b) Function type and parameters matches the definition
c) Symbol definition and declaration are both in c++
d) I have also included the .hpp file that has the
definition of the PError method in A.cpp.

You have _declaration_ in header (.h/.hpp) file and
_definition in source (.c/.cpp) file.

but still i am getting this error. What else could be the
other cause for it?

If A.dll imports something from B.dll, then you must ensure
following:

1. A.cpp file includes B.h header where necessary function
is declared.

2. A.dll project has B.lib import library listed in
additional dependencies section of linker properties.

3. KUsg::GetDefault is declared properly in B.h, i.e. there
is __declspec(dllimport/dllexport) attribute.

You should prepare import/export macro for B.dll:

#ifdef B_MODULE
#define B_MODULE_DECLSPEC __declspec(dllexport)
#else
#define B_MODULE_DECLSPEC __declspec(dllimport)
#endif

Then define B_MODULE macro for B.dll project. Declare
KUsg::GetDefault like this:

B_MODULE_DECLSPEC static long GetDefault();

Hope this helps
Alex