Undefined symbols linking to framework CMake - c

Question

When compiling/statically linking a project of mine, I get the following error (in this case with OpenAL, I've tried other audio libraries such as PulseAudio and get similar errors):
Undefined symbols for architecture x86_64:
"_alcCaptureCloseDevice", referenced from:
_ad_close in libsphinxbase.a(ad_openal.c.o)
"_alcCaptureOpenDevice", referenced from:
_ad_open_dev in libsphinxbase.a(ad_openal.c.o)
"_alcCaptureSamples", referenced from:
_ad_read in libsphinxbase.a(ad_openal.c.o)
"_alcCaptureStart", referenced from:
_ad_start_rec in libsphinxbase.a(ad_openal.c.o)
"_alcCaptureStop", referenced from:
_ad_stop_rec in libsphinxbase.a(ad_openal.c.o)
"_alcGetIntegerv", referenced from:
_ad_read in libsphinxbase.a(ad_openal.c.o)
ld: symbol(s) not found for architecture x86_64
You can find the CMakeLists.txt in the link to the project, but I think the error lies within its dependency (despite it compiling just fine and generating a x86_64 architecture library). Here is the dependency's main CMakeLists.txt:
#
# Initial CMake and project setup
#
CMAKE_MINIMUM_REQUIRED(VERSION 2.8 FATAL_ERROR)
SET(PROJECT_NAME sphinxbase)
PROJECT(${PROJECT_NAME})
SET(CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/cmake")
SET_DIRECTORY_PROPERTIES(PROPERTIES EP_PREFIX ${CMAKE_BINARY_DIR}/build-data)
#
# Setup compiler flags
#
if (NOT CMAKE_BUILD_TYPE)
message(STATUS "No build type selected, default to Release")
set(CMAKE_BUILD_TYPE CACHE Release FORCE)
endif()
set(CMAKE_C_FLAGS_DEBUG "${CMAKE_C_FLAGS_DEBUG} -std=gnu11 -O0 -fprofile-arcs -ftest-coverage")
set(CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS_RELEASE} -std=gnu11 -O3")
#
# Final project settings
#
configure_file("${CMAKE_SOURCE_DIR}/include/sphinx_config.h.in" "${CMAKE_SOURCE_DIR}/include/sphinx_config.h")
INCLUDE_DIRECTORIES(include)
ADD_SUBDIRECTORY(src)
ADD_SUBDIRECTORY(test EXCLUDE_FROM_ALL)
ADD_LIBRARY(${PROJECT_NAME} STATIC
$<TARGET_OBJECTS:libsphinxad>
$<TARGET_OBJECTS:fe>
$<TARGET_OBJECTS:feat>
$<TARGET_OBJECTS:lm>
$<TARGET_OBJECTS:util>
$<TARGET_OBJECTS:sphinx_adtools>
$<TARGET_OBJECTS:sphinx_cepview>
$<TARGET_OBJECTS:sphinx_fe>
$<TARGET_OBJECTS:sphinx_jsgf2fsg>
$<TARGET_OBJECTS:sphinx_lmtools>
)
TARGET_LINK_LIBRARIES(${PROJECT_NAME} ${LIBS})
I'm setting ${LIBS} in the libsphinxad object folder:
include_directories(${CMAKE_SOURCE_DIR}/include/sphinxbase)
if (WIN32)
set(SOURCES ${SOURCES} ad_win32.c)
endif ()
find_package(PulseAudio)
if (PULSEAUDIO_FOUND)
set(SOURCES ${SOURCES} ad_pulse.c)
set(LIBS ${PULSEAUDIO_LIBRARIES} CACHE INTERNAL "libs")
endif()
find_package(OSS)
if (OSS_FOUND)
set(SOURCES ${SOURCES} ad_oss.c )
endif()
find_package(OpenAL)
if (OPENAL_FOUND)
set(SOURCES ${SOURCES} ad_openal.c)
set(LIBS ${OPENAL_LIBRARY} CACHE INTERNAL "libs")
include_directories(${OPENAL_INCLUDE_DIR})
endif()
find_package(ALSA)
if (ALSA_FOUND)
set(SOURCES ${SOURCES} ad_alsa.c)
set(LIBS ${ALSA_LIBRARIES} CACHE INTERNAL "libs")
endif()
add_library(libsphinxad OBJECT ${SOURCES})
As you can see, I'm linking to the OpenAL framework. Here is the path that CMake is sending into TARGET_LINK_LIBRARIES that gives the error above:
/System/Library/Frameworks/OpenAL.framework
It looks like I'm doing things correctly, so I'm somewhat confused. I've tried adding -framework flags and adding linking to other libraries such as CoreAudio and Foundation to no avail. Any suggestion?
I have gotten the project to build without error linking to the dynamic library, but for my purposes I need to link the library statically.