If you have error cannot find symbol chk_ in cxx_non_shared etc..
Use the following patch (just one line to add)
diff --git a/avidemux_core/ADM_coreVideoCodec/ADM_hwAccel/ADM_coreLibVA/src/CMakeLists.txt b/avidemux_core/ADM_coreVideoCodec/ADM_hwAccel/ADM_coreLibVA/src/CMakeLists.txt
index e8c1af4..7d6f33e 100644
--- a/avidemux_core/ADM_coreVideoCodec/ADM_hwAccel/ADM_coreLibVA/src/CMakeLists.txt
+++ b/avidemux_core/ADM_coreVideoCodec/ADM_hwAccel/ADM_coreLibVA/src/CMakeLists.txt
@@ -8,4 +8,5 @@ ADM_ADD_SHARED_LIBRARY(ADM_coreLibVA6 ${ADM_libva_SRCS})
INCLUDE_DIRECTORIES(${CMAKE_SOURCE_DIR}/ADM_coreLibVA/include)
TARGET_LINK_LIBRARIES(ADM_coreLibVA6 va va-x11)
TARGET_LINK_LIBRARIES(ADM_coreLibVA6 ADM_core6 ADM_coreUI6 ADM_coreImage6)
+TARGET_LINK_LIBRARIES(ADM_coreLibVA6 "c")
ADM_INSTALL_LIB(ADM_coreLibVA6)