diff --git a/openair1/PHY/CODING/nrLDPC_decoder/nrLDPC_decoder_CL.c b/openair1/PHY/CODING/nrLDPC_decoder/nrLDPC_decoder_CL.c
index 01bcbbd68f..ebc792b8ba 100644
--- a/openair1/PHY/CODING/nrLDPC_decoder/nrLDPC_decoder_CL.c
+++ b/openair1/PHY/CODING/nrLDPC_decoder/nrLDPC_decoder_CL.c
@@ -110,6 +110,23 @@ char *clutil_getstrdev(int intdev) {
   return retstring;
 }
 
+void get_CompilErr(cl_program program, int pltf) {
+
+    // Determine the size of the log
+    size_t log_size;
+    for(int i=0; i<ocl.runtime[pltf].num_devices;i++) {
+      clGetProgramBuildInfo(program, ocl.runtime[pltf].devices[i], CL_PROGRAM_BUILD_LOG, 0, NULL, &log_size);
+    // Allocate memory for the log
+      char *log = (char *) malloc(log_size);
+    // Get the log
+      clGetProgramBuildInfo(program, ocl.runtime[pltf].devices[i], CL_PROGRAM_BUILD_LOG, log_size, log, NULL);
+    // Print the log
+      printf("%s\n", log);
+      free(log);
+    }
+
+}
+
 size_t load_source(char **source_str) {
 	int MAX_SOURCE_SIZE=(500*132);
     FILE *fp;
@@ -177,7 +194,10 @@ int ldpc_autoinit(void) {   // called by the library loader
         cl_program program = clCreateProgramWithSource(ocl.runtime[i].context, 1, 
                                                        (const char **)&source_str, (const size_t *)&source_size,  (cl_int *)&rt);
         AssertFatal(rt == CL_SUCCESS, "Error %d creating program for platform %i \n" , (int)rt, i); 
-        rt = clBuildProgram(program, ocl.runtime[i].num_devices,ocl.runtime[i].devices, NULL, NULL, NULL);   
+        rt = clBuildProgram(program, ocl.runtime[i].num_devices,ocl.runtime[i].devices, NULL, NULL, NULL);  
+        if (rt == CL_BUILD_PROGRAM_FAILURE) {
+			get_CompilErr(program,i);
+		} 
         AssertFatal(rt == CL_SUCCESS, "Error %d buildding program for platform %i \n" , rt, i);                                            
         context_ok++;
       }
diff --git a/openair1/PHY/CODING/nrLDPC_decoder/nrLDPC_decoder_kernels_CL.cl b/openair1/PHY/CODING/nrLDPC_decoder/nrLDPC_decoder_kernels_CL.cl
index fd1d46c454..f1f336d5e8 100644
--- a/openair1/PHY/CODING/nrLDPC_decoder/nrLDPC_decoder_kernels_CL.cl
+++ b/openair1/PHY/CODING/nrLDPC_decoder/nrLDPC_decoder_kernels_CL.cl
@@ -1,8 +1,8 @@
 
-define MAX_ITERATION 2
+#define define MAX_ITERATION 2
 #define MC	1
 
-
+#define INT32_MAX 2147483647
 
 typedef struct{
   char x;
@@ -10,28 +10,29 @@ typedef struct{
   short value;
 } h_element;
 
-char dev_const_llr[68*384];
-char dev_dt [46*68*384];
-char dev_llr[68*384];
-unsigned char dev_tmp[68*384];
+__constant char dev_const_llr[68*384]= {};
+//__global char dev_dt [46*68*384];
+//__local char *dev_t;
+//__global char dev_llr[68*384];
+//__global unsigned char dev_tmp[68*384];
 
-h_element h_compact1 [46*19] = {};
-h_element h_compact2 [68*30] = {};
+__constant h_element h_compact1 [46*19] = {};
+__constant h_element h_compact2 [68*30] = {};
 
-h_element dev_h_compact1[46*19];  // used in kernel 1
-h_element dev_h_compact2[68*30];  // used in kernel 2
+__constant h_element dev_h_compact1[46*19] = {};  // used in kernel 1
+__constant h_element dev_h_compact2[68*30] = {};  // used in kernel 2
 
-// __device__ __constant__ h_element dev_h_compact1[46*19];  // used in kernel 1
-// __device__ __constant__ h_element dev_h_compact2[68*30];  // used in kernel 2
+// __device__ __constantant__ h_element dev_h_compact1[46*19];  // used in kernel 1
+// __device__ __constantant__ h_element dev_h_compact2[68*30];  // used in kernel 2
 
 // row and col element count
-const char h_ele_row_bg1_count[46] = {
+__constant char h_ele_row_bg1_count[46] = {
 	19, 19, 19, 19, 3,  8,  9,  7, 10,  9,
 	7,  8,  7,  6,  7,  7,  6,  6,  6,  6,  
 	6,  6,  5,  5,  6,  5,  5,  4,  5,  5,  
 	5,  5,  5,  5,  5,  5,  5,  4,  5,  5,  
 	4,  5,  4,  5,  5,  4};
-const char h_ele_col_bg1_count[68] = {
+__constant char h_ele_col_bg1_count[68] = {
 	30, 28,  7, 11,  9,  4,  8, 12,  8,  7, 
 	12, 10, 12, 11, 10,  7, 10, 10, 13,  7,  
 	8,  11, 12,  5,  6,  6,  1,  1,  1,  1,  
@@ -39,13 +40,13 @@ const char h_ele_col_bg1_count[68] = {
 	1,   1,  1,  1,  1,  1,  1,  1,  1,  1,  
 	1,   1,  1,  1,  1,  1,  1,  1,  1,  1,  
 	1,   1,  1,  1,  1,  1,  1,  1};
-const char h_ele_row_bg2_count[42] = { 
+__constant char h_ele_row_bg2_count[42] = { 
 	8, 10,  8, 10,  4,  6,  6,  6,  4,  5, 
 	5,  5,  4,  5,  5,  4,  5,  5,  4,  4,
 	4,  4,  3,  4,  4,  3,  5,  3,  4,  3,
 	5,  3,  4,  4,  4,  4,  4,  3,  4,  4, 
 	4,  4};
-const char h_ele_col_bg2_count[52] = {
+__constant char h_ele_col_bg2_count[52] = {
 	22, 23, 10,  5,  5, 14,  7, 13,  6,  8, 
 	9,  16,  9, 12,  1,  1,  1,  1,  1,  1,
 	1,   1,  1,  1,  1,  1,  1,  1,  1,  1,
@@ -56,13 +57,13 @@ const char h_ele_col_bg2_count[52] = {
 
 
 // Kernel 1
-__kernel void ldpc_cnp_kernel_1st_iter(/*char * dev_llr,*/ int BG, int row, int col, int Zc)
+__kernel void ldpc_cnp_kernel_1st_iter( __local char * dev_llr, __local char * dev_dt, int BG, int row, int col, int Zc)
 {
 //	if(blockIdx.x == 0 && threadIdx.x == 1) printf("cnp %d\n", threadIdx.x);
-	int iMCW = blockIdx.y;		// codeword id
-	int iBlkRow = blockIdx.x;	// block row in h_base
+	int iMCW = get_group_id(1);		// codeword id
+	int iBlkRow = get_group_id(0);	// block row in h_base
 	int iBlkCol;				// block col in h_base
-	int iSubRow = threadIdx.x;	// row index in sub_block of h_base
+	int iSubRow = get_local_id(0);;	// row index in sub_block of h_base
 	int iCol;					// overall col index in h_base
 	int offsetR;
 	int shift_t;
@@ -125,13 +126,13 @@ __kernel void ldpc_cnp_kernel_1st_iter(/*char * dev_llr,*/ int BG, int row, int
 }
 
 // Kernel_1
-__kernel void ldpc_cnp_kernel(/*char * dev_llr, char * dev_dt,*/ int BG, int row, int col, int Zc)
+__kernel void ldpc_cnp_kernel( __local char * dev_llr, __local char * dev_dt, int BG, int row, int col, int Zc)
 {
 //	if(blockIdx.x == 0 && threadIdx.x == 1) printf("cnp\n");
-	int iMCW = blockIdx.y;
-	int iBlkRow = blockIdx.x;	// block row in h_base
+	int iMCW = get_group_id(1);
+	int iBlkRow = get_group_id(0);	// block row in h_base
 	int iBlkCol; 				// block col in h_base
-	int iSubRow = threadIdx.x;	// row index in sub_block of h_base
+	int iSubRow = get_local_id(0);;	// row index in sub_block of h_base
 	int iCol; 					// overall col index in h_base
 	int offsetR;
 	int shift_t;
@@ -198,12 +199,12 @@ __kernel void ldpc_cnp_kernel(/*char * dev_llr, char * dev_dt,*/ int BG, int row
 
 // Kernel 2: VNP processing
 __kernel void
-ldpc_vnp_kernel_normal(/*char * dev_llr, char * dev_dt, char * dev_const_llr,*/ int BG, int row, int col, int Zc)
+ldpc_vnp_kernel_normal(__local char * dev_llr, __local char * dev_dt, /* char * dev_const_llr,*/ int BG, int row, int col, int Zc)
 {	
-	int iMCW = blockIdx.y;
-	int iBlkCol = blockIdx.x;
+	int iMCW = get_group_id(1);
+	int iBlkCol = get_group_id(0);
 	int iBlkRow;
-	int iSubCol = threadIdx.x;
+	int iSubCol = get_local_id(0);
 	int iRow;
 	int iCol;
 
@@ -238,23 +239,23 @@ ldpc_vnp_kernel_normal(/*char * dev_llr, char * dev_dt, char * dev_const_llr,*/
 }
 
 
-__kernel void pack_decoded_bit(/*char *dev, unsigned char *host,*/ int col, int Zc)
+__kernel void pack_decoded_bit(__local unsigned char * dev_llr, __local unsigned char * dev_tmp, int col, int Zc)
 {
-	__shared__ unsigned char tmp[128];
-	int iMCW = blockIdx.y;
-	int tid = iMCW * col*Zc + blockIdx.x*128 + threadIdx.x;
-	int btid = threadIdx.x;
+	__local unsigned char tmp[128];
+	int iMCW = get_group_id(1);
+	int btid = get_local_id(0);
+	int tid = iMCW * col*Zc + get_group_id(0)*128 + btid;	
 	tmp[btid] = 0;
 	
 	if(dev_llr[tid] < 0){
 		tmp[btid] = 1 << (7-(btid&7));
 	}
-	__syncthreads();
+//	__syncthreads();
 	
-	if(threadIdx.x < 16){
-		dev_tmp[iMCW * col*Zc + blockIdx.x*16+threadIdx.x] = 0;
+	if(btid < 16){
+		dev_tmp[iMCW * col*Zc + get_group_id(0)*16+btid] = 0;
 		for(int i = 0; i < 8; i++){
-			dev_tmp[iMCW * col*Zc + blockIdx.x*16+threadIdx.x] += tmp[threadIdx.x*8+i];
+			dev_tmp[iMCW * col*Zc + get_group_id(0)*16+btid] += tmp[btid*8+i];
 		}
 	}
 }