CMake: Link a library to library

Question

I have a problem with cmake. I have, lets say, CMakeLists1 which has a subdirectory where CMakeLists2 is.

In CMakeLists2 my target is a static library. And I want to lin

Answer 1

I'm guessing the trouble will likely be that *name_of_external_lib* is not correct so it can't find it.

I would go with:

find_library(
    LIB_I_NEED name_of_external_lib
    HINTS "path_to_library"
)

if(${LIB_I_NEED} STREQUAL "LIB_I_NEED-NOTFOUND")
    message(FATAL_ERROR "Couldn't find the 'external_lib' library)
endif()

message(STATUS "Found 'external_lib' at: ${LIB_I_NEED}")

add_library (project2 ${sources})
target_link_libraries (project2 ${LIB_I_NEED})

---

If that doesn't help, have a quick read of the example in the cmake docs:

http://www.cmake.org/cmake/help/v2.8.8/cmake.html#command:target_link_libraries

One thing it mentions in there is:

While one repetition is usually sufficient, pathological object file and symbol arrangements can require more. One may handle such cases by manually repeating the component in the last target_link_libraries call

So I would say the other thing to try might be in project2:

set(PROJECT_2_LIBS project2 "name_of_external_lib" PARENT_SCOPE)

then in the exe:

target_link_libraries (project1 ${PROJECT_2_LIBS})

That will have the 'external_lib' linkage repeated in the two places and give you more chance of it working ;)