9 files changed, 46 insertions, 28 deletions
diff --git a/quantum/backlight/backlight_driver_common.c b/quantum/backlight/backlight_driver_common.c
index e4c2e90b5f..1eb8969084 100644
--- a/quantum/backlight/backlight_driver_common.c
+++ b/quantum/backlight/backlight_driver_common.c
@@ -9,7 +9,7 @@
 #if defined(BACKLIGHT_PINS)
 static const pin_t backlight_pins[] = BACKLIGHT_PINS;
 #    ifndef BACKLIGHT_LED_COUNT
-#        define BACKLIGHT_LED_COUNT (sizeof(backlight_pins) / sizeof(pin_t))
+#        define BACKLIGHT_LED_COUNT ARRAY_SIZE(backlight_pins)
 #    endif
 
 #    define FOR_EACH_LED(x)                                 \
diff --git a/quantum/backlight/backlight_software.c b/quantum/backlight/backlight_software.c
index 3d412cab52..27ccbd2c9f 100644
--- a/quantum/backlight/backlight_software.c
+++ b/quantum/backlight/backlight_software.c
@@ -26,7 +26,7 @@ static const uint16_t backlight_duty_table[] = {
     0b1110111011101110,
     0b1111111111111111,
 };
-#define backlight_duty_table_size (sizeof(backlight_duty_table) / sizeof(backlight_duty_table[0]))
+#define backlight_duty_table_size ARRAY_SIZE(backlight_duty_table)
 
 // clang-format on
 
diff --git a/quantum/dip_switch.c b/quantum/dip_switch.c
index eee29aaf91..e180cfccdf 100644
--- a/quantum/dip_switch.c
+++ b/quantum/dip_switch.c
@@ -33,7 +33,7 @@
 #endif
 
 #ifdef DIP_SWITCH_PINS
-#    define NUMBER_OF_DIP_SWITCHES (sizeof(dip_switch_pad) / sizeof(pin_t))
+#    define NUMBER_OF_DIP_SWITCHES (ARRAY_SIZE(dip_switch_pad))
 static pin_t dip_switch_pad[] = DIP_SWITCH_PINS;
 #endif
 
@@ -43,7 +43,7 @@ typedef struct matrix_index_t {
     uint8_t col;
 } matrix_index_t;
 
-#    define NUMBER_OF_DIP_SWITCHES (sizeof(dip_switch_pad) / sizeof(matrix_index_t))
+#    define NUMBER_OF_DIP_SWITCHES (ARRAY_SIZE(dip_switch_pad))
 static matrix_index_t dip_switch_pad[] = DIP_SWITCH_MATRIX_GRID;
 extern bool           peek_matrix(uint8_t row_index, uint8_t col_index, bool read_raw);
 static uint16_t       scan_count;
diff --git a/quantum/encoder.h b/quantum/encoder.h
index 82f95b4931..4eb67fa25d 100644
--- a/quantum/encoder.h
+++ b/quantum/encoder.h
@@ -32,17 +32,17 @@ void encoder_state_raw(uint8_t* slave_state);
 void encoder_update_raw(uint8_t* slave_state);
 
 #    if defined(ENCODERS_PAD_A_RIGHT)
-#        define NUM_ENCODERS_LEFT (sizeof(((pin_t[])ENCODERS_PAD_A)) / sizeof(pin_t))
-#        define NUM_ENCODERS_RIGHT (sizeof(((pin_t[])ENCODERS_PAD_A_RIGHT)) / sizeof(pin_t))
+#        define NUM_ENCODERS_LEFT ARRAY_SIZE(((pin_t[])ENCODERS_PAD_A))
+#        define NUM_ENCODERS_RIGHT ARRAY_SIZE(((pin_t[])ENCODERS_PAD_A_RIGHT))
 #    else
-#        define NUM_ENCODERS_LEFT (sizeof(((pin_t[])ENCODERS_PAD_A)) / sizeof(pin_t))
+#        define NUM_ENCODERS_LEFT ARRAY_SIZE(((pin_t[])ENCODERS_PAD_A))
 #        define NUM_ENCODERS_RIGHT NUM_ENCODERS_LEFT
 #    endif
 #    define NUM_ENCODERS (NUM_ENCODERS_LEFT + NUM_ENCODERS_RIGHT)
 
 #else // SPLIT_KEYBOARD
 
-#    define NUM_ENCODERS (sizeof(((pin_t[])ENCODERS_PAD_A)) / sizeof(pin_t))
+#    define NUM_ENCODERS ARRAY_SIZE(((pin_t[])ENCODERS_PAD_A))
 #    define NUM_ENCODERS_LEFT NUM_ENCODERS
 #    define NUM_ENCODERS_RIGHT 0
 
diff --git a/quantum/process_keycode/process_leader.c b/quantum/process_keycode/process_leader.c
index ae00b3227a..3593f75f0d 100644
--- a/quantum/process_keycode/process_leader.c
+++ b/quantum/process_keycode/process_leader.c
@@ -58,7 +58,7 @@ bool process_leader(uint16_t keycode, keyrecord_t *record) {
                     keycode = keycode & 0xFF;
                 }
 #    endif // LEADER_KEY_STRICT_KEY_PROCESSING
-                if (leader_sequence_size < (sizeof(leader_sequence) / sizeof(leader_sequence[0]))) {
+                if (leader_sequence_size < ARRAY_SIZE(leader_sequence)) {
                     leader_sequence[leader_sequence_size] = keycode;
                     leader_sequence_size++;
                 } else {
diff --git a/quantum/process_keycode/process_unicode_common.c b/quantum/process_keycode/process_unicode_common.c
index 8de31c055c..1c1aab8f48 100644
--- a/quantum/process_keycode/process_unicode_common.c
+++ b/quantum/process_keycode/process_unicode_common.c
@@ -25,7 +25,7 @@ bool             unicode_saved_num_lock;
 
 #if UNICODE_SELECTED_MODES != -1
 static uint8_t selected[]     = {UNICODE_SELECTED_MODES};
-static int8_t  selected_count = sizeof selected / sizeof *selected;
+static int8_t  selected_count = ARRAY_SIZE(selected);
 static int8_t  selected_index;
 #endif
 
diff --git a/quantum/rgb_matrix/rgb_matrix_drivers.c b/quantum/rgb_matrix/rgb_matrix_drivers.c
index 27fa7369bf..99151e5a92 100644
--- a/quantum/rgb_matrix/rgb_matrix_drivers.c
+++ b/quantum/rgb_matrix/rgb_matrix_drivers.c
@@ -369,7 +369,7 @@ static inline void setled(int i, uint8_t r, uint8_t g, uint8_t b) {
 }
 
 static void setled_all(uint8_t r, uint8_t g, uint8_t b) {
-    for (int i = 0; i < sizeof(rgb_matrix_ws2812_array) / sizeof(rgb_matrix_ws2812_array[0]); i++) {
+    for (int i = 0; i < ARRAY_SIZE(rgb_matrix_ws2812_array); i++) {
         setled(i, r, g, b);
     }
 }
diff --git a/quantum/secure.c b/quantum/secure.c
index f07f6af2cb..f2a567f31d 100644
--- a/quantum/secure.c
+++ b/quantum/secure.c
@@ -3,6 +3,7 @@
 
 #include "secure.h"
 #include "timer.h"
+#include "util.h"
 
 #ifndef SECURE_UNLOCK_TIMEOUT
 #    define SECURE_UNLOCK_TIMEOUT 5000
@@ -59,7 +60,7 @@ void secure_activity_event(void) {
 
 void secure_keypress_event(uint8_t row, uint8_t col) {
     static const uint8_t sequence[][2] = SECURE_UNLOCK_SEQUENCE;
-    static const uint8_t sequence_len  = sizeof(sequence) / sizeof(sequence[0]);
+    static const uint8_t sequence_len  = ARRAY_SIZE(sequence);
 
     static uint8_t offset = 0;
     if ((sequence[offset][0] == row) && (sequence[offset][1] == col)) {
diff --git a/quantum/util.h b/quantum/util.h
index 21c290013c..9c034cc404 100644
--- a/quantum/util.h
+++ b/quantum/util.h
@@ -1,19 +1,7 @@
-/*
-Copyright 2011 Jun Wako <wakojun@gmail.com>
-
-This program is free software: you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation, either version 2 of the License, or
-(at your option) any later version.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
+// Copyright 2022 Stefan Kerkmann (KarlK90)
+// Copyright 2011 Jun Wako <wakojun@gmail.com>
+// SPDX-License-Identifier: GPL-2.0-or-later
+
 #pragma once
 
 #include "bitwise.h"
@@ -29,3 +17,32 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #if !defined(MAX)
 #    define MAX(x, y) (((x) > (y)) ? (x) : (y))
 #endif
+
+#if !defined(CEILING)
+/**
+ * @brief Computes the rounded up result of a division of two integers at
+ * compile time.
+ */
+#    define CEILING(dividend, divisor) (((dividend) + (divisor)-1) / (divisor))
+#endif
+
+#if !defined(IS_ARRAY)
+/**
+ * @brief Returns true if the value is an array, false if it's a pointer.
+ *
+ * This macro is ill-formed for scalars, which is OK for its intended use in
+ * ARRAY_SIZE.
+ */
+#    define IS_ARRAY(value) (!__builtin_types_compatible_p(typeof((value)), typeof(&(value)[0])))
+#endif
+
+#if !defined(ARRAY_SIZE)
+/**
+ * @brief Computes the number of elements of the given array at compile time.
+ *
+ * This Macro can only be used for statically allocated arrays that have not
+ * been decayed into a pointer. This is detected at compile time, though the
+ * error message for scalar values is poor.
+ */
+#    define ARRAY_SIZE(array) (__builtin_choose_expr(IS_ARRAY((array)), sizeof((array)) / sizeof((array)[0]), (void)0))
+#endif