diff --git a/src/keycode.cpp b/src/keycode.cpp
index 3551c385a..cedd0803b 100644
--- a/src/keycode.cpp
+++ b/src/keycode.cpp
@@ -246,9 +246,9 @@ static const struct table_key table[] = {
 
 struct table_key lookup_keyname(const char *name)
 {
-	for (u16 i = 0; i < ARRLEN(table); i++) {
-		if (strcmp(table[i].Name, name) == 0)
-			return table[i];
+	for (const auto &table_key : table) {
+		if (strcmp(table_key.Name, name) == 0)
+			return table_key;
 	}
 
 	throw UnknownKeycode(name);
@@ -256,9 +256,9 @@ struct table_key lookup_keyname(const char *name)
 
 struct table_key lookup_keykey(irr::EKEY_CODE key)
 {
-	for (u16 i = 0; i < ARRLEN(table); i++) {
-		if (table[i].Key == key)
-			return table[i];
+	for (const auto &table_key : table) {
+		if (table_key.Key == key)
+			return table_key;
 	}
 
 	std::ostringstream os;
@@ -268,9 +268,9 @@ struct table_key lookup_keykey(irr::EKEY_CODE key)
 
 struct table_key lookup_keychar(wchar_t Char)
 {
-	for (u16 i = 0; i < ARRLEN(table); i++) {
-		if (table[i].Char == Char)
-			return table[i];
+	for (const auto &table_key : table) {
+		if (table_key.Char == Char)
+			return table_key;
 	}
 
 	std::ostringstream os;
@@ -285,7 +285,9 @@ KeyPress::KeyPress(const char *name)
 		Char = L'\0';
 		m_name = "";
 		return;
-	} else if (strlen(name) <= 4) {
+	}
+
+	if (strlen(name) <= 4) {
 		// Lookup by resulting character
 		int chars_read = mbtowc(&Char, name, 1);
 		FATAL_ERROR_IF(chars_read != 1, "Unexpected multibyte character");
@@ -339,7 +341,7 @@ const char *KeyPress::sym() const
 
 const char *KeyPress::name() const
 {
-	if (m_name == "")
+	if (m_name.empty())
 		return "";
 	const char *ret;
 	if (valid_kcode(Key))
diff --git a/src/keycode.h b/src/keycode.h
index 9352fa4c0..7036705d1 100644
--- a/src/keycode.h
+++ b/src/keycode.h
@@ -30,7 +30,8 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 class KeyPress
 {
 public:
-	KeyPress() {}
+	KeyPress() = default;
+
 	KeyPress(const char *name);
 
 	KeyPress(const irr::SEvent::SKeyInput &in, bool prefer_character = false);
diff --git a/src/light.cpp b/src/light.cpp
index b269f6233..575bc2c72 100644
--- a/src/light.cpp
+++ b/src/light.cpp
@@ -18,7 +18,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 */
 
 #include "light.h"
-#include <math.h>
+#include <cmath>
 #include "util/numeric.h"
 #include "settings.h"
 
diff --git a/src/localplayer.cpp b/src/localplayer.cpp
index 62066bb18..9248494f7 100644
--- a/src/localplayer.cpp
+++ b/src/localplayer.cpp
@@ -38,13 +38,9 @@ LocalPlayer::LocalPlayer(Client *client, const char *name):
 {
 }
 
-LocalPlayer::~LocalPlayer()
-{
-}
-
 static aabb3f getNodeBoundingBox(const std::vector<aabb3f> &nodeboxes)
 {
-	if (nodeboxes.size() == 0)
+	if (nodeboxes.empty())
 		return aabb3f(0, 0, 0, 0, 0, 0);
 
 	aabb3f b_max;
@@ -103,8 +99,8 @@ bool LocalPlayer::updateSneakNode(Map *map, const v3f &position,
 	m_sneak_ladder_detected = false;
 	f32 min_distance_f = 100000.0 * BS;
 
-	for (s16 d = 0; d < 9; d++) {
-		const v3s16 p = current_node + dir9_center[d];
+	for (const auto &d : dir9_center) {
+		const v3s16 p = current_node + d;
 		const v3f pf = intToFloat(p, BS);
 		const v2f diff(position.X - pf.X, position.Z - pf.Z);
 		f32 distance_f = diff.getLength();
@@ -389,9 +385,8 @@ void LocalPlayer::move(f32 dtime, Environment *env, f32 pos_max_d,
 
 	// Dont report if flying
 	if(collision_info && !(g_settings->getBool("free_move") && fly_allowed)) {
-		for(size_t i=0; i<result.collisions.size(); i++) {
-			const CollisionInfo &info = result.collisions[i];
-			collision_info->push_back(info);
+		for (const auto &colinfo : result.collisions) {
+			collision_info->push_back(colinfo);
 		}
 	}
 
@@ -938,7 +933,7 @@ void LocalPlayer::old_move(f32 dtime, Environment *env, f32 pos_max_d,
 
 			// The node to be sneaked on has to be walkable
 			node = map->getNodeNoEx(p, &is_valid_position);
-			if (!is_valid_position || nodemgr->get(node).walkable == false)
+			if (!is_valid_position || !nodemgr->get(node).walkable)
 				continue;
 			// And the node above it has to be nonwalkable
 			node = map->getNodeNoEx(p + v3s16(0, 1, 0), &is_valid_position);
@@ -965,9 +960,7 @@ void LocalPlayer::old_move(f32 dtime, Environment *env, f32 pos_max_d,
 			MapNode n = map->getNodeNoEx(m_sneak_node);
 			std::vector<aabb3f> nodeboxes;
 			n.getCollisionBoxes(nodemgr, &nodeboxes);
-			for (std::vector<aabb3f>::iterator it = nodeboxes.begin();
-					it != nodeboxes.end(); ++it) {
-				aabb3f box = *it;
+			for (const auto &box : nodeboxes) {
 				if (box.MaxEdge.Y > cb_max)
 					cb_max = box.MaxEdge.Y;
 			}
@@ -994,8 +987,7 @@ void LocalPlayer::old_move(f32 dtime, Environment *env, f32 pos_max_d,
 	*/
 	// Dont report if flying
 	if (collision_info && !(g_settings->getBool("free_move") && fly_allowed)) {
-		for (size_t i = 0; i < result.collisions.size(); i++) {
-			const CollisionInfo &info = result.collisions[i];
+		for (const auto &info : result.collisions) {
 			collision_info->push_back(info);
 		}
 	}
diff --git a/src/localplayer.h b/src/localplayer.h
index 9965897ac..c64e0042a 100644
--- a/src/localplayer.h
+++ b/src/localplayer.h
@@ -43,7 +43,7 @@ class LocalPlayer : public Player
 {
 public:
 	LocalPlayer(Client *client, const char *name);
-	virtual ~LocalPlayer();
+	virtual ~LocalPlayer() = default;
 
 	ClientActiveObject *parent = nullptr;
 
diff --git a/src/log.h b/src/log.h
index d02d85a4b..6a1c24dec 100644
--- a/src/log.h
+++ b/src/log.h
@@ -205,9 +205,7 @@ extern std::ostream dstream;
 #define dout_con (*dout_con_ptr)
 #define derr_con (*derr_con_ptr)
 #define dout_server (*dout_server_ptr)
-#define derr_server (*derr_server_ptr)
 
 #ifndef SERVER
 	#define dout_client (*dout_client_ptr)
-	#define derr_client (*derr_client_ptr)
 #endif