Xcode, CMake unable to link C library with ObjC library-CodePudding

The

Clearly, the core/ library functions are not accessible inside platform/.

I have tried fiddling with C and CXX flags, trying to add library using find_library first, and using different toolchain, for example, this one here as well.

Platform specifications:

MacOS Big Sur, 11.6.5, 2.3 Ghz i9

CMake - 3.22.2

Xcode - 13.2.1

CodePudding user response：

Assume libcore_lib.a is under core/

find_package(CORE core_lib HINTS ${PROJECT_SOURCE_DIR}/core) include_directories(${PROJECT_SOURCE_DIR}/core) add_library(pim_ios ${PLATFORM_SOURCES}) target_link_libraries(pim_ios ${CORE}) target_link_libraries(pim_ios PUBLIC "-framework Cocoa" "-framework AppKit" "-framework CoreData" "-framework Foundation")

CodePudding user response：

Alright, I finally got what was the problem.

The libraries I was generating, were static libraries.

Static libraries cannot resolve their dependencies on their own (i.e., here, library in platform/ cannot resolve its dependency of core/) unless I explicitly add both of them to Xcode.

It started working after I added both libraries (core/ library and platform/) in Xcode.

Explanation:

Static Library: Though you specify a dependency, it's not resolved by the toolchain. You'd have to specify all dependencies to the final executable.

e.g: libB depends on libA then when linking hello.exe which only calls methods of libB you've to specify both libB.a AND libA.a too for it to work

Dynamic/Shared Library: Dependencies b/w libraries are resolved; just specifying the dependency needed by the final executable is good enough

You'd still have to make sure both .dylibs are in the same directory for libB.dylib to load libA.dylib

So, either create a dynamic library or add all the dependencies of the static library in Xcode as well.