WebGL with C++ static library

Is it possible to use C++ static library for Unity WebGL?

First, I generate the llvm bitcode by using "clang -emit-llvm -o libhello_webgl.bc -c hello_webgl.cpp"
Second, I drop this libhello_webgl.bc in the floder "Assets"--"Plugins"--"WebGL"
Third, I create the C# script to import this function like this:
[DllImport("__Internal")]
private static extern int sum_dll_webgl(int x, int y);

Unfortunately, the error message is "libhello_webgl.bc is not valid according to llvm-nm, can not link"

If I use the C++ source code instead of this static library, it works.

Thank you for your suggestion.

 

This forum is dead?
I solved this problem, the reason is the version of emscripten, the default version in Unity is very old.

 

Yes, you should use emscripten to build the static lib.
And it'll be helpful if you'll write here how you solved it...
emscripten version? build command line?
Thanks