How to link with CMake library?

[yh-sb]

I added CMake FreeRTOS-Kernel library into my xmake project.
Compilation passed fine, but I'm struggling with adding properties (includedirs, linking with built library) of this CMake library into my project. I see build\.packages\f\freertos\latest\cache\build_016a2dd3\libfreertos_kernel.a library, but don't know how to use it as an xmake dependency.
How to do it properly?

How I add CMake library into xmake:

package("freertos")
    add_deps("cmake")
    set_sourcedir(path.join(os.scriptdir(), "third_party/FreeRTOS-Kernel"))
    on_install(function (package)
        local configs = {
            "-DCMAKE_TRY_COMPILE_TARGET_TYPE=STATIC_LIBRARY",
            "-DCMAKE_SYSTEM_NAME=Generic",
            "-DCMAKE_SYSTEM_PROCESSOR=arm",
            "-DCMAKE_C_FLAGS=" .. table.concat(compile_flags, " "),
            "-DFREERTOS_PORT=GCC_ARM_CM4F",
            "-DFREERTOS_CONFIG_FILE_DIRECTORY=" .. path.absolute(os.projectdir())
        }
        import("package.tools.cmake").install(package, configs)
    end)
package_end()

Then how I try to use it:

add_requires("freertos")

target("stm32f4.elf")
    add_packages("freertos")
    add_files(
        "main.cpp"
    )

As a result, I get undefined reference to ... errors during linking final binary.

In my old CMake project I successfully linked binary with freertos_kernel CMake target created by FreeRTOS kernel CMake. So, freertos_kernel has all includedirs and library name attributes.

[waruqi]

install .a libfiles to package/installdir/lib

[yh-sb]

Where is exactly should this directory be located? Should I created it by my own?

I have the following directory structure in the build/.packages:

└── f
    └── freertos
        └── latest
            ├── 016a2dd3009745daad8f2d3925729e5b
            │   └── lib
            │       └── pkgconfig
            └── cache
                └── build_016a2dd3
                    ├── CMakeFiles
                    │   ├── 3.30.3
                    │   │   ├── CompilerIdC
                    │   │   │   └── tmp
                    │   │   └── CompilerIdCXX
                    │   │       └── tmp
                    │   ├── CMakeScratch
                    │   ├── freertos_kernel.dir
                    │   │   └── portable
                    │   │       └── MemMang
                    │   └── pkgRedirects
                    ├── include
                    │   └── CMakeFiles
                    ├── install
                    └── portable
                        └── CMakeFiles
                            └── freertos_kernel_port.dir
                                └── GCC
                                    └── ARM_CM4F

[yh-sb]

Ok, I understood that build\.packages\f\freertos\latest\016a2dd3009745daad8f2d3925729e5b\lib is the right directory to install .a libs.

        os.cp(package:buildir() .. "/portable/libfreertos_kernel_port.a", package:installdir("lib"))
        os.cp(package:buildir() .. "/libfreertos_kernel.a", package:installdir("lib"))