diff --git a/lib/CMakeLists.txt b/lib/CMakeLists.txt
index e6dd115..6c45f51 100644
--- a/lib/CMakeLists.txt
+++ b/lib/CMakeLists.txt
@@ -59,7 +59,7 @@
     ESCAPE_QUOTES
 @ONLY)
 
-add_sources(constants.cc)
+list(APPEND grgsm_sources ${CMAKE_CURRENT_BINARY_DIR}/constants.cc)
 #########################################################################
 # Subdirecories
 #########################################################################
diff --git a/lib/decoding/CMakeLists.txt b/lib/decoding/CMakeLists.txt
index 0305a07..144c006 100644
--- a/lib/decoding/CMakeLists.txt
+++ b/lib/decoding/CMakeLists.txt
@@ -18,11 +18,12 @@
 # Boston, MA 02110-1301, USA.
 
 
+add_subdirectory(osmocom/coding)
+add_subdirectory(openbts)
+
 add_sources(
     control_channels_decoder_impl.cc
     tch_f_decoder_impl.cc
     sch.c
 )
 
-add_subdirectory(osmocom/coding)
-add_subdirectory(openbts)
diff --git a/lib/decoding/osmocom/coding/CMakeLists.txt b/lib/decoding/osmocom/coding/CMakeLists.txt
index 615a2f6..8e68577 100644
--- a/lib/decoding/osmocom/coding/CMakeLists.txt
+++ b/lib/decoding/osmocom/coding/CMakeLists.txt
@@ -17,7 +17,7 @@
 # the Free Software Foundation, Inc., 51 Franklin Street,
 # Boston, MA 02110-1301, USA.
 
-add_sources(APPEND grgsm_sources
+add_sources(
     gsm0503_conv.c
     gsm0503_coding.c
     gsm0503_interleaving.c