How to eliminate Warning LNK4221?

Question

I am working on a project using c++/windows forms (visual studio 2010), we have 4 projects:

• 1 project containing GUI windows forms {managed code} and this is the

Answer 1

I had a c++ static library with an empty module in it, linking which in non-optimized mode gave me that LNK4221 warning. (in Visual Studio) I went to Librarian->All Options, and added "/ignore:4221" to Additional Options. So, the warning has disappeared.

Answer 2

This was kind of just my particular problem but if your .cpp doesn't define any new functions or has empty bodies for constructor functions, you will get this warning. I used an initialization list for my constructor so the body was empty.

Answer 3

You get this warning because you use only template classes in cpp file. To get rid of it, insert one simple function with no template.

Answer 4

Disclaimer: This solution is indeed terrible, and this code should not be added to production build! It is only useful to "hide" the warning.

A better solution would be to remove the file in question from the compilation, as it is anyway useless.

Original post:

I had a the problem with this warning originating from several dependencies, and I found that it was caused by some translation unit being empty, i.e. empty source files.

These files actually had a content but it was deactivated for visual studio so I just added at the beginning:

__declspec( dllexport ) void getRidOfLNK4221(){}

And now my project compiles without any warning :)

Hope it helps, even if this is a late answer!

Answer 5

See this: https://docs.microsoft.com/en-us/cpp/error-messages/tool-errors/linker-tools-warning-lnk4221

In summary, the file exports nothing, so linker does not link, as it thinks it's a waste of effort