CMake: how create a single shared library from all static libraries of subprojects?

Question

I have the following layout:

top_project
    + subproject1
    + subproject2

Each of subproject1 and subproject2

Answer 1

I am not sure if this is what suits your need, but cmake also offers INTERFACE libraries, which serve (among others) precisely this need.

add_library(bundle INTERFACE)
target_link_libraries(bundle lib1 lib2)

will bundle lib1 and lib2 into a single library, and inherit the PUBLIC and INTERFACE section of lib1 and lib2.

More info here.