diff --git a/common/cardhelper.c b/common/cardhelper.c
index 623e1c1f4..fc4fe2503 100644
--- a/common/cardhelper.c
+++ b/common/cardhelper.c
@@ -22,6 +22,7 @@
 #include "cmdsmartcard.h"
 #include "ui.h"
 #include "util.h"
+#include "commonutil.h"
 
 #define CARD_INS_DECRYPT    0x01
 #define CARD_INS_ENCRYPT    0x02
@@ -78,7 +79,7 @@ bool IsHIDSamPresent(bool verbose) {
         {11, {0x3b, 0x90, 0x96, 0x91, 0x81, 0xb1, 0xfe, 0x55, 0x1f, 0xc7, 0xd4}},
     };
     bool found = false;
-    for (int i = 0; i < sizeof(supported) / sizeof(supported[0]); i++) {
+    for (int i = 0; i < ARRAYLEN(supported); i++) {
         if ((card.atr_len == supported[i].atr_len) &&
                 (memcmp(card.atr, supported[i].atr, supported[i].atr_len) == 0)) {
             found = true;
diff --git a/tools/hitag2crack/crack5opencl/opencl.c b/tools/hitag2crack/crack5opencl/opencl.c
index aadca459a..79b7b1e92 100644
--- a/tools/hitag2crack/crack5opencl/opencl.c
+++ b/tools/hitag2crack/crack5opencl/opencl.c
@@ -23,6 +23,7 @@ License: GNU General Public License v3 or any later version (see LICENSE.txt)
 ****************************************************************************/
 
 #include "opencl.h"
+#define ARRAYLEN(x) (sizeof(x)/sizeof((x)[0]))
 
 bool plat_dev_enabled(unsigned int id, const unsigned int *sel,
                       unsigned int cnt, unsigned int cur_type, unsigned int allow_type) {
@@ -106,10 +107,10 @@ int discoverDevices(unsigned int profile_selected, uint32_t device_types_selecte
     }
 
     cl_platform_info ocl_platforms_info[3] = { CL_PLATFORM_NAME, CL_PLATFORM_VENDOR, CL_PLATFORM_VERSION };
-    unsigned int ocl_platforms_info_cnt = sizeof(ocl_platforms_info) / sizeof(cl_platform_info);
+    unsigned int ocl_platforms_info_cnt = ARRAYLEN(ocl_platforms_info);
 
     cl_device_info ocl_devices_info[8] = { CL_DEVICE_TYPE, CL_DEVICE_NAME, CL_DEVICE_VERSION, CL_DRIVER_VERSION, CL_DEVICE_VENDOR, CL_DEVICE_LOCAL_MEM_TYPE, CL_DEVICE_MAX_WORK_ITEM_SIZES, CL_DEVICE_MAX_COMPUTE_UNITS };
-    unsigned int ocl_devices_info_cnt = sizeof(ocl_devices_info) / sizeof(cl_device_info);
+    unsigned int ocl_devices_info_cnt = ARRAYLEN(ocl_devices_info);
 
     unsigned int info_idx;
     size_t tmp_len = 0;