diff --git a/ext/mysqli/tests/065.phpt b/ext/mysqli/tests/065.phpt
index 0a6ca356a205..3e06fafc568c 100644
--- a/ext/mysqli/tests/065.phpt
+++ b/ext/mysqli/tests/065.phpt
@@ -16,8 +16,6 @@ require_once 'skipifconnectfailure.inc';
         printf("[002] Cannot set SQL-Mode, [%d] %s\n", mysqli_errno($mysql), mysqli_error($mysql));
 
     $esc_str = chr(0xbf) . chr(0x5c);
-    $len = $charset = array();
-    $tmp = null;
 
     if ($mysql->set_charset("latin1")) {
         /* 5C should be escaped */
diff --git a/ext/mysqli/tests/071.phpt b/ext/mysqli/tests/071.phpt
index c5b569a664b0..8fb150feca26 100644
--- a/ext/mysqli/tests/071.phpt
+++ b/ext/mysqli/tests/071.phpt
@@ -11,7 +11,6 @@ require_once 'skipifconnectfailure.inc';
     require_once 'connect.inc';
 
     $mysql = new my_mysqli($host, $user, $passwd, $db, $port, $socket);
-    $version = $mysql->server_version;
 
     var_dump($mysql->query('DO 1'));
 
diff --git a/ext/mysqli/tests/bug45289.phpt b/ext/mysqli/tests/bug45289.phpt
index 87256659f74c..d1591bd9b403 100644
--- a/ext/mysqli/tests/bug45289.phpt
+++ b/ext/mysqli/tests/bug45289.phpt
@@ -24,7 +24,7 @@ require_once 'skipifconnectfailure.inc';
     if (!$stmt->bind_param('i', $id) || !$stmt->execute())
         printf("[003] [%d] %s\n", $stmt->errno, $stmt->error);
 
-    if ($res = $link->store_result()) {
+    if ($link->store_result()) {
         printf("[004] Can store result!\n");
     } else {
         printf("[004] [%d] %s\n", $link->errno, $link->error);
diff --git a/ext/mysqli/tests/bug55283.phpt b/ext/mysqli/tests/bug55283.phpt
index 4517e26cc303..f5473c7c4959 100644
--- a/ext/mysqli/tests/bug55283.phpt
+++ b/ext/mysqli/tests/bug55283.phpt
@@ -43,8 +43,6 @@ $link->close();
 --FILE--
 <?php
     require_once 'connect.inc';
-    $db1 = new mysqli();
-
 
     $flags = MYSQLI_CLIENT_SSL | MYSQLI_CLIENT_SSL_DONT_VERIFY_SERVER_CERT;
 
diff --git a/ext/mysqli/tests/bug62885.phpt b/ext/mysqli/tests/bug62885.phpt
index 888f8b658903..8666795bd87c 100644
--- a/ext/mysqli/tests/bug62885.phpt
+++ b/ext/mysqli/tests/bug62885.phpt
@@ -16,7 +16,6 @@ try {
     echo $e->getMessage() . \PHP_EOL;
 }
 
-$test2 = array();
 $test2 = array();
 try {
     $test1 = mysqli_poll($test2, $test3, $tablica, 0);
diff --git a/ext/mysqli/tests/bug66124.phpt b/ext/mysqli/tests/bug66124.phpt
index 521c17e8fb99..d63f04e63cfd 100644
--- a/ext/mysqli/tests/bug66124.phpt
+++ b/ext/mysqli/tests/bug66124.phpt
@@ -16,7 +16,6 @@ $table_create = "CREATE TABLE `test` (
 
 $table_insert = "INSERT INTO `test` SET `id`=?";
 $table_select = "SELECT * FROM `test`";
-$table_delete = "DELETE FROM `test`";
 $id = '1311200011005001566';
 
 
diff --git a/ext/mysqli/tests/bug72489.phpt b/ext/mysqli/tests/bug72489.phpt
index e1ed342d4440..0c10bcd19cc4 100644
--- a/ext/mysqli/tests/bug72489.phpt
+++ b/ext/mysqli/tests/bug72489.phpt
@@ -45,8 +45,6 @@ while ($stmt->fetch()) {
 
 echo "Finished 1\n";
 
-$newArray = array();
-
 echo "Finished 2\n";
 
 ?>
diff --git a/ext/mysqli/tests/bug76386.phpt b/ext/mysqli/tests/bug76386.phpt
index 8c4a7a7710b9..5ff4bb403100 100644
--- a/ext/mysqli/tests/bug76386.phpt
+++ b/ext/mysqli/tests/bug76386.phpt
@@ -67,7 +67,7 @@ $link->query('INSERT INTO t_test VALUES ();');
 $stmt = $link->prepare('SELECT * FROM t_test;');
 if ($stmt) {
     $stmt->execute();
-    $tid = $t = $t2 = $t3 = $t4 = null;
+    $tid = $t = $t2 = $t4 = null;
     $stmt->bind_result($tid, $t, $t2, $t4, $t6);
     while ($stmt->fetch()) {
         var_dump($t, $t2, $t4, $t6);
diff --git a/ext/mysqli/tests/fetch/mysqli_fetch_all_data_types_variation.phpt b/ext/mysqli/tests/fetch/mysqli_fetch_all_data_types_variation.phpt
index a7383ec48dc1..69fc427001fd 100644
--- a/ext/mysqli/tests/fetch/mysqli_fetch_all_data_types_variation.phpt
+++ b/ext/mysqli/tests/fetch/mysqli_fetch_all_data_types_variation.phpt
@@ -44,8 +44,6 @@ function func_mysqli_fetch_all(
     $tmp = mysqli_fetch_all($result, MYSQLI_BOTH);
     $row = $tmp[0];
 
-    $fields = mysqli_fetch_fields($result);
-
     if ($regexp_comparison) {
         if (!preg_match($regexp_comparison, (string)$row['label']) || !preg_match($regexp_comparison, (string)$row[1])) {
             printf("[%04d] Expecting %s/%s [reg exp = %s], got %s/%s resp. %s/%s. [%d] %s\n", $offset + 4,
diff --git a/ext/mysqli/tests/gh14255.phpt b/ext/mysqli/tests/gh14255.phpt
index 375eda0c5b52..bdf63e36dfb2 100644
--- a/ext/mysqli/tests/gh14255.phpt
+++ b/ext/mysqli/tests/gh14255.phpt
@@ -16,13 +16,13 @@ mysqli_report(MYSQLI_REPORT_STRICT|MYSQLI_REPORT_ERROR);
 $mysqli = my_mysqli_connect($host, $user, $passwd, $db, $port, $socket);
 
 $ca = $mysqli->query('SELECT 1 ');
-$c = $ca->fetch_assoc();
+$ca->fetch_assoc();
 try {
     $mysqli->query('SELECT non_existent_column');
 } catch (Exception $e) {
     echo "Caught exception"."\n";
 }
-$c = $ca->fetch_assoc();
+$ca->fetch_assoc();
 
 print "done!";
 ?>
diff --git a/ext/mysqli/tests/gh9841.phpt b/ext/mysqli/tests/gh9841.phpt
index 28d720aa6e90..1e8683379e58 100644
--- a/ext/mysqli/tests/gh9841.phpt
+++ b/ext/mysqli/tests/gh9841.phpt
@@ -33,7 +33,7 @@ $mysqli->real_query("SELECT (
     UNION ALL
     SELECT 2
 ) FROM dual");
-$result = new mysqli_result($mysqli);
+new mysqli_result($mysqli);
 
 // now make sure the errors are thrown when not using silent mode
 mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
@@ -65,7 +65,7 @@ $mysqli->real_query("SELECT (
     SELECT 2
 ) FROM dual");
 try {
-    $result = new mysqli_result($mysqli);
+    new mysqli_result($mysqli);
 } catch (mysqli_sql_exception $e) {
     echo $e->getMessage()."\n";
 }
diff --git a/ext/mysqli/tests/mysqli_affected_rows.phpt b/ext/mysqli/tests/mysqli_affected_rows.phpt
index 2547720b3146..3a56884d148b 100644
--- a/ext/mysqli/tests/mysqli_affected_rows.phpt
+++ b/ext/mysqli/tests/mysqli_affected_rows.phpt
@@ -78,8 +78,7 @@ mysqli
     if (1 !== ($tmp = mysqli_affected_rows($link)))
         printf("[025] Expecting int/1, got %s/%s\n", gettype($tmp), $tmp);
 
-    $charsets = array('utf8');
-    foreach ($charsets as $k => $charset) {
+    foreach (['utf8'] as $charset) {
         if (!($res = mysqli_query($link, sprintf("SHOW CHARACTER SET LIKE '%s'", $charset))))
             continue;
         mysqli_free_result($res);
diff --git a/ext/mysqli/tests/mysqli_begin_transaction.phpt b/ext/mysqli/tests/mysqli_begin_transaction.phpt
index 7a7d7e36fba4..5dbd9dbc4954 100644
--- a/ext/mysqli/tests/mysqli_begin_transaction.phpt
+++ b/ext/mysqli/tests/mysqli_begin_transaction.phpt
@@ -31,7 +31,7 @@ if (!have_innodb($link))
 
     /* overrule autocommit */
     if (true !== ($tmp = mysqli_begin_transaction($link)))
-        printf("[011] Got %s - [%d] %s\n", var_dump($tmp, true), mysqli_errno($link), mysqli_error($link));
+        printf("[011] Got %s - [%d] %s\n", $tmp, mysqli_errno($link), mysqli_error($link));
 
     if (!mysqli_query($link, 'INSERT INTO test(id) VALUES (1)'))
         printf("[012] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
@@ -72,7 +72,7 @@ if (!have_innodb($link))
         } else if (!mysqli_commit($link)) {
             printf("[018] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
         } else {
-            $res = mysqli_query($link, "SELECT id FROM test WHERE id = 2");
+            mysqli_query($link, "SELECT id FROM test WHERE id = 2");
         }
     }
 
diff --git a/ext/mysqli/tests/mysqli_change_user_new.phpt b/ext/mysqli/tests/mysqli_change_user_new.phpt
index d6a9a3bd137c..e52a91e984de 100644
--- a/ext/mysqli/tests/mysqli_change_user_new.phpt
+++ b/ext/mysqli/tests/mysqli_change_user_new.phpt
@@ -20,9 +20,6 @@ if (mysqli_get_server_version($link) >= 10_00_00)
 <?php
     require_once 'connect.inc';
 
-    $tmp	= NULL;
-    $link	= NULL;
-
     if (!$link = my_mysqli_connect($host, $user, $passwd, $db, $port, $socket))
         printf("[001] Cannot connect to the server using host=%s, user=%s, passwd=***, dbname=%s, port=%s, socket=%s\n",
             $host, $user, $db, $port, $socket);
diff --git a/ext/mysqli/tests/mysqli_change_user_old.phpt b/ext/mysqli/tests/mysqli_change_user_old.phpt
index 1e2bfcc302f3..fd418220ae80 100644
--- a/ext/mysqli/tests/mysqli_change_user_old.phpt
+++ b/ext/mysqli/tests/mysqli_change_user_old.phpt
@@ -17,9 +17,6 @@ if (mysqli_get_server_version($link) >= 50600 && mysqli_get_server_version($link
 <?php
     require_once 'connect.inc';
 
-    $tmp	= NULL;
-    $link	= NULL;
-
     if (!$link = my_mysqli_connect($host, $user, $passwd, $db, $port, $socket))
         printf("[006] Cannot connect to the server using host=%s, user=%s, passwd=***, dbname=%s, port=%s, socket=%s\n",
             $host, $user, $db, $port, $socket);
diff --git a/ext/mysqli/tests/mysqli_change_user_oo.phpt b/ext/mysqli/tests/mysqli_change_user_oo.phpt
index ea7873f31b31..32e30e4e7496 100644
--- a/ext/mysqli/tests/mysqli_change_user_oo.phpt
+++ b/ext/mysqli/tests/mysqli_change_user_oo.phpt
@@ -15,9 +15,6 @@ if (mysqli_get_server_version($link) >= 50600)
 <?php
     require_once 'connect.inc';
 
-    $link	= NULL;
-    $tmp	= NULL;
-
     $mysqli = new my_mysqli($host, $user, $passwd, $db, $port, $socket);
 
     if (false !== ($tmp = $mysqli->change_user($user . '_unknown_really', $passwd . 'non_empty', $db)))
diff --git a/ext/mysqli/tests/mysqli_change_user_rollback.phpt b/ext/mysqli/tests/mysqli_change_user_rollback.phpt
index bcef28cd1d51..2185a3083d6f 100644
--- a/ext/mysqli/tests/mysqli_change_user_rollback.phpt
+++ b/ext/mysqli/tests/mysqli_change_user_rollback.phpt
@@ -30,7 +30,7 @@ if (!have_innodb($link))
     $num = $row['_num'];
     assert($num > 0);
 
-    if (!$res = mysqli_query($link, 'DELETE FROM test'))
+    if (false === mysqli_query($link, 'DELETE FROM test'))
         printf("[004] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
     if (!$res = mysqli_query($link, 'SELECT COUNT(*) AS _num FROM test'))
diff --git a/ext/mysqli/tests/mysqli_class_mysqli_properties_no_conn.phpt b/ext/mysqli/tests/mysqli_class_mysqli_properties_no_conn.phpt
index 46ccbf61a9da..0c0b012d8702 100644
--- a/ext/mysqli/tests/mysqli_class_mysqli_properties_no_conn.phpt
+++ b/ext/mysqli/tests/mysqli_class_mysqli_properties_no_conn.phpt
@@ -15,7 +15,7 @@ require_once 'skipifconnectfailure.inc';
         printf("\nClass variables:\n");
         $variables = array_keys(get_class_vars(get_class($mysqli)));
         sort($variables);
-        foreach ($variables as $k => $var) {
+        foreach ($variables as $var) {
             try {
                 printf("%s = '%s'\n", $var, var_export($mysqli->$var, true));
             } catch (Error $exception) {
@@ -25,7 +25,7 @@ require_once 'skipifconnectfailure.inc';
 
         printf("\nObject variables:\n");
         $variables = array_keys(get_object_vars($mysqli));
-        foreach ($variables as $k => $var) {
+        foreach ($variables as $var) {
             try {
                 printf("%s = '%s'\n", $var, var_export($mysqli->$var, true));
             } catch (Error $exception) {
diff --git a/ext/mysqli/tests/mysqli_class_mysqli_result_interface.phpt b/ext/mysqli/tests/mysqli_class_mysqli_result_interface.phpt
index 4e23de5cab54..5b79f7a197d9 100644
--- a/ext/mysqli/tests/mysqli_class_mysqli_result_interface.phpt
+++ b/ext/mysqli/tests/mysqli_class_mysqli_result_interface.phpt
@@ -69,12 +69,12 @@ require_once 'skipifconnectfailure.inc';
     printf("\nClass variables:\n");
     $variables = array_keys(get_class_vars(get_class($mysqli_result)));
     sort($variables);
-    foreach ($variables as $k => $var)
+    foreach ($variables as $var)
         printf("%s\n", $var);
 
     printf("\nObject variables:\n");
     $variables = array_keys(get_object_vars($mysqli_result));
-    foreach ($variables as $k => $var)
+    foreach ($variables as $var)
         printf("%s\n", $var);
 
     printf("\nMagic, magic properties:\n");
@@ -121,9 +121,9 @@ require_once 'skipifconnectfailure.inc';
     if (!mysqli_query($link, "SELECT id FROM test ORDER BY id"))
         printf("[003] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
-    $res = new mysqli_result($link);
-    $res = new mysqli_result($link, MYSQLI_STORE_RESULT);
-    $res = new mysqli_result($link, MYSQLI_USE_RESULT);
+    new mysqli_result($link);
+    new mysqli_result($link, MYSQLI_STORE_RESULT);
+    new mysqli_result($link, MYSQLI_USE_RESULT);
 
     $valid = array(MYSQLI_STORE_RESULT, MYSQLI_USE_RESULT);
     do {
@@ -132,7 +132,7 @@ require_once 'skipifconnectfailure.inc';
 
     if ($TEST_EXPERIMENTAL) {
         ob_start();
-        $res = new mysqli_result($link, $mode);
+        new mysqli_result($link, $mode);
         $content = ob_get_contents();
         ob_end_clean();
         if (!stristr($content, 'Invalid value for resultmode'))
diff --git a/ext/mysqli/tests/mysqli_class_mysqli_stmt_interface.phpt b/ext/mysqli/tests/mysqli_class_mysqli_stmt_interface.phpt
index 09d08de7d295..cc7e36727639 100644
--- a/ext/mysqli/tests/mysqli_class_mysqli_stmt_interface.phpt
+++ b/ext/mysqli/tests/mysqli_class_mysqli_stmt_interface.phpt
@@ -68,12 +68,12 @@ mysqli
     printf("\nClass variables:\n");
     $variables = array_keys(get_class_vars(get_class($stmt)));
     sort($variables);
-    foreach ($variables as $k => $var)
+    foreach ($variables as $var)
         printf("%s\n", $var);
 
     printf("\nObject variables:\n");
     $variables = array_keys(get_object_vars($stmt));
-    foreach ($variables as $k => $var)
+    foreach ($variables as $var)
         printf("%s\n", $var);
 
 printf("\nMagic, magic properties:\n");
diff --git a/ext/mysqli/tests/mysqli_connect.phpt b/ext/mysqli/tests/mysqli_connect.phpt
index cf276d6886f6..ad903c9e1e5d 100644
--- a/ext/mysqli/tests/mysqli_connect.phpt
+++ b/ext/mysqli/tests/mysqli_connect.phpt
@@ -10,15 +10,13 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require_once 'connect.inc';
 
-    $tmp    = NULL;
-    $link   = NULL;
-
     /* we need to check, if the server allows anonymous login (empty user) */
     $tmp = @mysqli_connect('localhost');
     $anon_allow = (gettype($tmp) == "object");
 
     $exptype = ($anon_allow) ? "mysqli_object" : "false";
 
+    $link = NULL;
     $tmp = @mysqli_connect($link);
     if (($anon_allow && gettype($tmp) != "object") || (!$anon_allow && $tmp != false)) {
         printf("[002] Expecting %s, got %s/%s\n", $exptype, gettype($tmp), $tmp);
diff --git a/ext/mysqli/tests/mysqli_connect_attr.phpt b/ext/mysqli/tests/mysqli_connect_attr.phpt
index 323a87b74682..cf86aecfc6ed 100644
--- a/ext/mysqli/tests/mysqli_connect_attr.phpt
+++ b/ext/mysqli/tests/mysqli_connect_attr.phpt
@@ -37,9 +37,6 @@ mysqli_close($link);
 <?php
     require_once 'connect.inc';
 
-    $tmp    = NULL;
-    $link   = NULL;
-    $res    = NULL;
     if (!$link = mysqli_connect($host, $user, $passwd, $db, $port, $socket))
         printf("[001] Cannot connect to the server using host=%s, user=%s, passwd=***, dbname=%s, port=%s, socket=%s\n",$host, $user, $db, $port, $socket);
 
diff --git a/ext/mysqli/tests/mysqli_connect_errno.phpt b/ext/mysqli/tests/mysqli_connect_errno.phpt
index 75b226aa678d..20b6c25718b5 100644
--- a/ext/mysqli/tests/mysqli_connect_errno.phpt
+++ b/ext/mysqli/tests/mysqli_connect_errno.phpt
@@ -10,7 +10,6 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require_once 'connect.inc';
 
-    $tmp    = NULL;
     $link   = NULL;
 
     // too many parameter
diff --git a/ext/mysqli/tests/mysqli_connect_error.phpt b/ext/mysqli/tests/mysqli_connect_error.phpt
index 175b8d52eae5..6d5a230302ec 100644
--- a/ext/mysqli/tests/mysqli_connect_error.phpt
+++ b/ext/mysqli/tests/mysqli_connect_error.phpt
@@ -10,7 +10,6 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require_once 'connect.inc';
 
-    $tmp    = NULL;
     $link   = NULL;
 
     // too many parameter
@@ -29,7 +28,7 @@ require_once 'skipifconnectfailure.inc';
 
     mysqli_close($link);
 
-    if ($link = @my_mysqli_connect($host, $user . 'unknown_really', $passwd . 'non_empty', $db, $port, $socket))
+    if (false !== @my_mysqli_connect($host, $user . 'unknown_really', $passwd . 'non_empty', $db, $port, $socket))
         printf("[003] Connect to the server should fail using host=%s, user=%s, passwd=***non_empty, dbname=%s, port=%s, socket=%s\n",
             $host, $user . 'unknown_really', $db, $port, $socket);
 
diff --git a/ext/mysqli/tests/mysqli_connect_oo.phpt b/ext/mysqli/tests/mysqli_connect_oo.phpt
index d40db06c0453..5bf56acbd0cd 100644
--- a/ext/mysqli/tests/mysqli_connect_oo.phpt
+++ b/ext/mysqli/tests/mysqli_connect_oo.phpt
@@ -10,11 +10,6 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require_once 'connect.inc';
 
-    $tmp    = NULL;
-    $link   = NULL;
-
-    $obj = new stdClass();
-
     if ($mysqli = new mysqli($host, $user . 'unknown_really', $passwd . 'non_empty', $db, $port, $socket) && !mysqli_connect_errno())
         printf("[003] Can connect to the server using host=%s, user=%s, passwd=***non_empty, dbname=%s, port=%s, socket=%s\n",
             $host, $user . 'unknown_really', $db, $port, $socket);
diff --git a/ext/mysqli/tests/mysqli_connect_oo_defaults.phpt b/ext/mysqli/tests/mysqli_connect_oo_defaults.phpt
index ca2a5ab4c567..6660139d5296 100644
--- a/ext/mysqli/tests/mysqli_connect_oo_defaults.phpt
+++ b/ext/mysqli/tests/mysqli_connect_oo_defaults.phpt
@@ -10,9 +10,6 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require_once 'connect.inc';
 
-    $tmp    = NULL;
-    $link   = NULL;
-
     if ($socket != "")
         /* mysqli.default_socket requires non-empty string */
         ini_set('mysqli.default_socket', 'socket');
diff --git a/ext/mysqli/tests/mysqli_constants.phpt b/ext/mysqli/tests/mysqli_constants.phpt
index 20def1043d37..8f755400e4b0 100644
--- a/ext/mysqli/tests/mysqli_constants.phpt
+++ b/ext/mysqli/tests/mysqli_constants.phpt
@@ -107,7 +107,6 @@ $expected_constants['MYSQLI_STORE_RESULT_COPY_DATA'] = true;
 
 $expected_constants['MYSQLI_REFRESH_BACKUP_LOG'] = true;
 
-$version = 50007 + 1;
 $expected_constants['MYSQLI_OPT_NET_CMD_BUFFER_SIZE'] = true;
 $expected_constants['MYSQLI_OPT_NET_READ_BUFFER_SIZE'] = true;
 $expected_constants['MYSQLI_ASYNC'] = true;
@@ -154,7 +153,7 @@ $expected_constants["MYSQLI_TYPE_JSON"]	= true;
 
 $unexpected_constants = array();
 
-foreach ($constants as $group => $consts) {
+foreach ($constants as $consts) {
     foreach ($consts as $name => $value) {
         if (stristr($name, 'mysqli')) {
             $name = strtoupper($name);
diff --git a/ext/mysqli/tests/mysqli_debug_control_string.phpt b/ext/mysqli/tests/mysqli_debug_control_string.phpt
index b745ed2ebce8..a589155c2a98 100644
--- a/ext/mysqli/tests/mysqli_debug_control_string.phpt
+++ b/ext/mysqli/tests/mysqli_debug_control_string.phpt
@@ -31,7 +31,7 @@ if (defined('MYSQLI_DEBUG_TRACE_ENABLED') && !MYSQLI_DEBUG_TRACE_ENABLED)
             return false;
         }
 
-        if (!$res = mysqli_query($link, 'SELECT * FROM test')) {
+        if (false === mysqli_query($link, 'SELECT * FROM test')) {
             printf("[%03d][control string '%s'] [%d] %s.\n",
                 $offset + 2,
                 $control_string,
diff --git a/ext/mysqli/tests/mysqli_debug_mysqlnd_control_string.phpt b/ext/mysqli/tests/mysqli_debug_mysqlnd_control_string.phpt
index e46f4aed1984..b6876e31f1a8 100644
--- a/ext/mysqli/tests/mysqli_debug_mysqlnd_control_string.phpt
+++ b/ext/mysqli/tests/mysqli_debug_mysqlnd_control_string.phpt
@@ -40,7 +40,7 @@ if (defined('MYSQLI_DEBUG_TRACE_ENABLED') && !MYSQLI_DEBUG_TRACE_ENABLED)
                 mysqli_error($link));
             return false;
         }
-        while ($row = mysqli_fetch_assoc($res))
+        while (mysqli_fetch_assoc($res))
             ;
         mysqli_free_result($res);
 
@@ -97,7 +97,7 @@ if (defined('MYSQLI_DEBUG_TRACE_ENABLED') && !MYSQLI_DEBUG_TRACE_ENABLED)
     // -t,[N] - maximum nesting level
     $trace = try_control_string($link, 't,1:n:O,' . $trace_file, $trace_file, 70);
     $lines = explode("\n", $trace);
-    foreach ($lines as $k => $line) {
+    foreach ($lines as $line) {
         $line = trim($line);
         if (!preg_match("@^(\d+):+@ismU", $line, $matches)) {
             printf("[075] Nesting level seem to be missing, first characters from trace are '%s'\n", substr($line, 0, 80));
@@ -113,7 +113,7 @@ if (defined('MYSQLI_DEBUG_TRACE_ENABLED') && !MYSQLI_DEBUG_TRACE_ENABLED)
     // omitting t
     $trace = try_control_string($link, 'n:O,' . $trace_file, $trace_file, 80);
     $lines = explode("\n", $trace);
-    foreach ($lines as $k => $line) {
+    foreach ($lines as $line) {
         $line = trim($line);
         if (preg_match("@^[|\s]*>[\w]+@ism", $line, $matches)) {
             printf("[085] Looks like a function call, but there should be none in the trace file, first characters from trace are '%s'\n",
@@ -124,7 +124,7 @@ if (defined('MYSQLI_DEBUG_TRACE_ENABLED') && !MYSQLI_DEBUG_TRACE_ENABLED)
     // -f[,functions] - Limit debugger list to specified functions. Empty list -> all functions
     $lines_all_funcs = explode("\n", try_control_string($link, 't:O,' . $trace_file, $trace_file, 90));
     $functions_all_funcs = array();
-    foreach ($lines_all_funcs as $k => $line) {
+    foreach ($lines_all_funcs as $line) {
         $line = trim($line);
         if (preg_match("@^[|\s]*>([\w:]+)@ism", $line, $matches)) {
             $functions_all_funcs[$matches[1]] = $matches[1];
@@ -133,7 +133,7 @@ if (defined('MYSQLI_DEBUG_TRACE_ENABLED') && !MYSQLI_DEBUG_TRACE_ENABLED)
 
     $lines_trace = explode("\n", try_control_string($link, 't:f:O,' . $trace_file, $trace_file, 100));
     $functions_trace = array();
-    foreach ($lines_trace as $k => $line) {
+    foreach ($lines_trace as $line) {
         $line = trim($line);
         if (preg_match("@^[|\s]*>([\w:]+)@ism", $line, $matches)) {
             $functions_trace[$matches[1]] = $matches[1];
@@ -169,7 +169,7 @@ if (defined('MYSQLI_DEBUG_TRACE_ENABLED') && !MYSQLI_DEBUG_TRACE_ENABLED)
 
     $lines_trace = explode("\n", try_control_string($link, $control_string, $trace_file, 110));
     $functions_trace = array();
-    foreach ($lines_trace as $k => $line) {
+    foreach ($lines_trace as $line) {
         $line = trim($line);
         if (preg_match("@^[|\s]*>([\w:]+)@ism", $line, $matches)) {
             $functions_trace[$matches[1]] = $matches[1];
diff --git a/ext/mysqli/tests/mysqli_debug_mysqlnd_only.phpt b/ext/mysqli/tests/mysqli_debug_mysqlnd_only.phpt
index ccee53b02cf9..5327042127c3 100644
--- a/ext/mysqli/tests/mysqli_debug_mysqlnd_only.phpt
+++ b/ext/mysqli/tests/mysqli_debug_mysqlnd_only.phpt
@@ -39,7 +39,7 @@ if (defined('MYSQLI_DEBUG_TRACE_ENABLED') && !MYSQLI_DEBUG_TRACE_ENABLED)
                 mysqli_error($link));
             return false;
         }
-        while ($row = mysqli_fetch_assoc($res))
+        while (mysqli_fetch_assoc($res))
             ;
         mysqli_free_result($res);
 
@@ -73,7 +73,7 @@ if (defined('MYSQLI_DEBUG_TRACE_ENABLED') && !MYSQLI_DEBUG_TRACE_ENABLED)
 
     $lines_trace = explode("\n", $trace);
     $functions_trace = array();
-    foreach ($lines_trace as $k => $line) {
+    foreach ($lines_trace as $line) {
         $line = trim($line);
         if (preg_match("@^[|\s]*>([\w:]+)@ism", $line, $matches)) {
             $functions_trace[$matches[1]] = $matches[1];
@@ -81,7 +81,7 @@ if (defined('MYSQLI_DEBUG_TRACE_ENABLED') && !MYSQLI_DEBUG_TRACE_ENABLED)
     }
 
     $found = 0;
-    foreach ($memory_funcs as $k => $name)
+    foreach ($memory_funcs as $name)
         if (isset($functions_trace[$name]))
             $found++;
 
@@ -97,7 +97,7 @@ if (defined('MYSQLI_DEBUG_TRACE_ENABLED') && !MYSQLI_DEBUG_TRACE_ENABLED)
 
     $lines_trace = explode("\n", $trace);
     $functions_trace = array();
-    foreach ($lines_trace as $k => $line) {
+    foreach ($lines_trace as $line) {
         $line = trim($line);
         if (preg_match("@^[|\s]*>([\w:]+)@ism", $line, $matches)) {
             $functions_trace[$matches[1]] = $matches[1];
@@ -105,7 +105,7 @@ if (defined('MYSQLI_DEBUG_TRACE_ENABLED') && !MYSQLI_DEBUG_TRACE_ENABLED)
     }
 
     $found = 0;
-    foreach ($memory_funcs as $k => $name)
+    foreach ($memory_funcs as $name)
         if (isset($functions_trace[$name]))
             $found++;
 
diff --git a/ext/mysqli/tests/mysqli_dump_debug_info_oo.phpt b/ext/mysqli/tests/mysqli_dump_debug_info_oo.phpt
index 40c53827a752..fba8032823f5 100644
--- a/ext/mysqli/tests/mysqli_dump_debug_info_oo.phpt
+++ b/ext/mysqli/tests/mysqli_dump_debug_info_oo.phpt
@@ -10,9 +10,6 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require_once 'connect.inc';
 
-    $tmp	= NULL;
-    $link	= NULL;
-
     if (!$mysqli = new mysqli($host, $user, $passwd, $db, $port, $socket))
         printf("[001] Cannot connect to the server using host=%s, user=%s, passwd=***, dbname=%s, port=%s, socket=%s\n", $host, $user, $db, $port, $socket);
 
diff --git a/ext/mysqli/tests/mysqli_errno_oo.phpt b/ext/mysqli/tests/mysqli_errno_oo.phpt
index e6ef7b217395..3331995175f4 100644
--- a/ext/mysqli/tests/mysqli_errno_oo.phpt
+++ b/ext/mysqli/tests/mysqli_errno_oo.phpt
@@ -10,9 +10,6 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require_once 'connect.inc';
 
-    $tmp    = NULL;
-    $link   = NULL;
-
     $mysqli = new mysqli();
     if (0 !== ($tmp = @$mysqli->errno))
         printf("[001] Expecting int/0, got %s/%s\n", gettype($tmp), $tmp);
diff --git a/ext/mysqli/tests/mysqli_error_oo.phpt b/ext/mysqli/tests/mysqli_error_oo.phpt
index 2e8473bb53ed..4f1a971043f9 100644
--- a/ext/mysqli/tests/mysqli_error_oo.phpt
+++ b/ext/mysqli/tests/mysqli_error_oo.phpt
@@ -10,9 +10,6 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require_once 'connect.inc';
 
-    $tmp    = NULL;
-    $link   = NULL;
-
     $mysqli = new mysqli();
     if ('' !== ($tmp = @$mysqli->error))
         printf("[001] Expecting empty string, got %s/'%s'\n", gettype($tmp), $tmp);
diff --git a/ext/mysqli/tests/mysqli_execute_query.phpt b/ext/mysqli/tests/mysqli_execute_query.phpt
index dafb37116c2f..5730d827a406 100644
--- a/ext/mysqli/tests/mysqli_execute_query.phpt
+++ b/ext/mysqli/tests/mysqli_execute_query.phpt
@@ -36,7 +36,7 @@ if (!($tmp = $link->execute_query("SELECT ? AS a, ? AS b, ? AS c", [42, "foo", n
 assert($tmp->fetch_assoc() === ['a' => '42', 'b' => 'foo', 'c' => null]);
 
 // prepare error
-if (!($tmp = $link->execute_query("some random gibberish", [1, "foo"]))) {
+if (false === $link->execute_query("some random gibberish", [1, "foo"])) {
     printf("[005] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 }
 
diff --git a/ext/mysqli/tests/mysqli_explain_metadata.phpt b/ext/mysqli/tests/mysqli_explain_metadata.phpt
index a5ddf5462a51..36067365ff67 100644
--- a/ext/mysqli/tests/mysqli_explain_metadata.phpt
+++ b/ext/mysqli/tests/mysqli_explain_metadata.phpt
@@ -26,7 +26,7 @@ require_once 'skipifconnectfailure.inc';
             $field_names[$name] = gettype($value);
     }
 
-    while ($row = mysqli_fetch_assoc($res))
+    while (mysqli_fetch_assoc($res))
         $num_rows++;
 
     if (($tmp = mysqli_num_rows($res)) !== $num_rows) {
@@ -43,12 +43,12 @@ require_once 'skipifconnectfailure.inc';
             $num_fields, gettype($tmp), $tmp);
     }
 
-    foreach ($fields as $k => $field) {
+    foreach ($fields as $field) {
         $field->max_length = 0;// change it or we will get diff error
         if (isset($field_names[$field->name])) {
             unset($field_names[$field->name]);
         } else {
-            printf("[006] Unexpected field '%s', dumping info\n");
+            printf("[006] Unexpected field '%s', dumping info\n", $field->name);
             var_dump($field);
         }
     }
diff --git a/ext/mysqli/tests/mysqli_fetch_all_oo.phpt b/ext/mysqli/tests/mysqli_fetch_all_oo.phpt
index cfe8f8464be2..8cd3984d7037 100644
--- a/ext/mysqli/tests/mysqli_fetch_all_oo.phpt
+++ b/ext/mysqli/tests/mysqli_fetch_all_oo.phpt
@@ -86,14 +86,14 @@ require_once 'skipifconnectfailure.inc';
             return false;
         }
 
-        if (!$link->query($sql = sprintf("CREATE TABLE test(id INT NOT NULL, label %s, PRIMARY KEY(id)) ENGINE = %s", $sql_type, $engine))) {
+        if (!$link->query(sprintf("CREATE TABLE test(id INT NOT NULL, label %s, PRIMARY KEY(id)) ENGINE = %s", $sql_type, $engine))) {
                 // don't bail, engine might not support the datatype
                 return false;
         }
 
         if (is_null($php_value)) {
             if (!$link->query($sql = sprintf("INSERT INTO test(id, label) VALUES (1, NULL)"))) {
-                printf("[%04d] [%d] %s\n", $offset + 1, $link->errno, $link->error);
+                printf("[%04d] [%d] %s - %s\n", $offset + 1, $link->errno, $link->error, $sql);
                 return false;
             }
         } else {
@@ -104,7 +104,7 @@ require_once 'skipifconnectfailure.inc';
                 }
             } else {
                 if (!$link->query($sql = sprintf("INSERT INTO test(id, label) VALUES (1, '%d')", $sql_value))) {
-                    printf("[%04di] [%d] %s\n", $offset + 1, $link->errno, $link->error);
+                    printf("[%04di] [%d] %s - %s\n", $offset + 1, $link->errno, $link->error, $sql);
                     return false;
                 }
             }
diff --git a/ext/mysqli/tests/mysqli_fetch_array.phpt b/ext/mysqli/tests/mysqli_fetch_array.phpt
index 2ec58913fb55..6b3fe79a582b 100644
--- a/ext/mysqli/tests/mysqli_fetch_array.phpt
+++ b/ext/mysqli/tests/mysqli_fetch_array.phpt
@@ -31,7 +31,7 @@ require_once 'skipifconnectfailure.inc';
     mysqli_free_result($res);
 
     if (!$res = mysqli_query($link, "SELECT 1 AS a, 2 AS a, 3 AS c, 4 AS C, NULL AS d, true AS e")) {
-        printf("[010] Cannot run query, [%d] %s\n", mysqli_errno($link), $mysqli_error($link));
+        printf("[010] Cannot run query, [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
     print "[011]\n";
     var_dump(mysqli_fetch_array($res, MYSQLI_BOTH));
@@ -39,7 +39,7 @@ require_once 'skipifconnectfailure.inc';
     mysqli_free_result($res);
     if (!$res = mysqli_query($link, "SELECT 1 AS a, 2 AS b, 3 AS c, 4 AS C")) {
         printf("[012] Cannot run query, [%d] %s\n",
-            mysqli_errno($link), $mysqli_error($link));
+            mysqli_errno($link), mysqli_error($link));
         exit(1);
     }
 
@@ -61,7 +61,7 @@ require_once 'skipifconnectfailure.inc';
 
     mysqli_free_result($res);
 
-    function func_mysqli_fetch_array($link, $engine, $sql_type, $sql_value, $php_value, $offset, $regexp_comparison = NULL, $binary_type = false) {
+    function func_mysqli_fetch_array($link, $engine, $sql_type, $sql_value, $php_value, $offset, $regexp_comparison = NULL) {
 
         if (!mysqli_query($link, "DROP TABLE IF EXISTS test")) {
             printf("[%04d] [%d] %s\n", $offset, mysqli_errno($link), mysqli_error($link));
diff --git a/ext/mysqli/tests/mysqli_fetch_array_many_rows.phpt b/ext/mysqli/tests/mysqli_fetch_array_many_rows.phpt
index 4650475e7333..cb11d2793035 100644
--- a/ext/mysqli/tests/mysqli_fetch_array_many_rows.phpt
+++ b/ext/mysqli/tests/mysqli_fetch_array_many_rows.phpt
@@ -12,7 +12,6 @@ require_once 'skipifconnectfailure.inc';
     require 'table.inc';
 
     // do as much as we can do in 5 seconds
-    $start = microtime(true);
     for ($id = 100, $start = microtime(true); (microtime(true) - $start) < 5; $id++) {
         if (!mysqli_query($link, $sql = sprintf("INSERT INTO test(id, label) VALUES (%d, '%s')",
             $id, mysqli_real_escape_string($link, chr(65 + ($id % 26)))))) {
@@ -52,7 +51,7 @@ require_once 'skipifconnectfailure.inc';
         }
         if ($row[0] !== $row['id']) {
             printf("[005] Unexpected result row[0] = '%s', row[id] = '%s', [%d] %s\n",
-                $row[0], $row[id], mysqli_errno($link), mysqli_error($link));
+                $row[0], $row['id'], mysqli_errno($link), mysqli_error($link));
             break;
         }
 
diff --git a/ext/mysqli/tests/mysqli_fetch_array_oo.phpt b/ext/mysqli/tests/mysqli_fetch_array_oo.phpt
index 8639b7419b12..225ac6711bd2 100644
--- a/ext/mysqli/tests/mysqli_fetch_array_oo.phpt
+++ b/ext/mysqli/tests/mysqli_fetch_array_oo.phpt
@@ -70,14 +70,14 @@ require_once 'skipifconnectfailure.inc';
             return false;
         }
 
-        if (!$mysqli->query($sql = sprintf("CREATE TABLE test(id INT NOT NULL, label %s, PRIMARY KEY(id)) ENGINE = %s", $sql_type, $engine))) {
+        if (!$mysqli->query(sprintf("CREATE TABLE test(id INT NOT NULL, label %s, PRIMARY KEY(id)) ENGINE = %s", $sql_type, $engine))) {
                 // don't bail, engine might not support the datatype
                 return false;
         }
 
         if (is_null($php_value)) {
             if (!$mysqli->query($sql = sprintf("INSERT INTO test(id, label) VALUES (1, NULL)"))) {
-                printf("[%04d] [%d] %s\n", $offset + 1, $mysqli->errno, $mysqli->error);
+                printf("[%04d] [%d] %s - %s\n", $offset + 1, $mysqli->errno, $mysqli->error, $sql);
                 return false;
             }
         } else {
@@ -88,7 +88,7 @@ require_once 'skipifconnectfailure.inc';
                 }
             } else {
                 if (!$mysqli->query($sql = sprintf("INSERT INTO test(id, label) VALUES (1, '%d')", $sql_value))) {
-                    printf("[%04di] [%d] %s\n", $offset + 1, $mysqli->errno, $mysqli->error);
+                    printf("[%04di] [%d] %s - %s\n", $offset + 1, $mysqli->errno, $mysqli->error, $sql);
                     return false;
                 }
             }
diff --git a/ext/mysqli/tests/mysqli_fetch_assoc_bit.phpt b/ext/mysqli/tests/mysqli_fetch_assoc_bit.phpt
index 76b6e6fb1bc3..9f3197b903c4 100644
--- a/ext/mysqli/tests/mysqli_fetch_assoc_bit.phpt
+++ b/ext/mysqli/tests/mysqli_fetch_assoc_bit.phpt
@@ -39,7 +39,6 @@ if (mysqli_get_server_version($link) < 50003)
             $max_value = 1;
         else
             $max_value = pow(2, $bits) - 1;
-        $tests = 0;
         if (!mysqli_query($link, "DROP TABLE IF EXISTS test") ||
             !mysqli_query($link, $sql = sprintf('CREATE TABLE test(id BIGINT, bit_value BIT(%d) NOT NULL, bit_null BIT(%d) DEFAULT NULL) ENGINE="%s"', $bits, $bits, $engine)))
             printf("[002 - %d] [%d] %s\n",$bits, mysqli_errno($link), mysqli_error($link));
diff --git a/ext/mysqli/tests/mysqli_fetch_assoc_no_alias.phpt b/ext/mysqli/tests/mysqli_fetch_assoc_no_alias.phpt
index 418a22a223e2..a5da83a9039b 100644
--- a/ext/mysqli/tests/mysqli_fetch_assoc_no_alias.phpt
+++ b/ext/mysqli/tests/mysqli_fetch_assoc_no_alias.phpt
@@ -39,7 +39,7 @@ require_once 'skipifconnectfailure.inc';
     mysqli_free_result($res);
 
     /* Now do it with unbuffered queries */
-    if (!$res = mysqli_real_query($link, "SELECT 1, 2")) {
+    if (false === mysqli_real_query($link, "SELECT 1, 2")) {
         printf("[009] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
     if (!$res = mysqli_use_result($link)) {
@@ -49,7 +49,7 @@ require_once 'skipifconnectfailure.inc';
     var_dump(mysqli_fetch_assoc($res));
     mysqli_free_result($res);
 
-    if (!$res = mysqli_real_query($link, "SELECT 1 AS a, 2")) {
+    if (false === mysqli_real_query($link, "SELECT 1 AS a, 2")) {
         printf("[012] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
     if (!$res = mysqli_use_result($link)) {
@@ -59,7 +59,7 @@ require_once 'skipifconnectfailure.inc';
     var_dump(mysqli_fetch_assoc($res));
     mysqli_free_result($res);
 
-    if (!$res = mysqli_real_query($link, "SELECT 1 AS a, 2, 2 as '2'")) {
+    if (false === mysqli_real_query($link, "SELECT 1 AS a, 2, 2 as '2'")) {
         printf("[015] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
     if (!$res = mysqli_use_result($link)) {
@@ -69,7 +69,7 @@ require_once 'skipifconnectfailure.inc';
     var_dump(mysqli_fetch_assoc($res));
     mysqli_free_result($res);
 
-    if (!$res = mysqli_real_query($link, "SELECT 1 AS a, 2 as '2', 2")) {
+    if (false === mysqli_real_query($link, "SELECT 1 AS a, 2 as '2', 2")) {
         printf("[015] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
     if (!$res = mysqli_use_result($link)) {
diff --git a/ext/mysqli/tests/mysqli_fetch_assoc_no_alias_utf8.phpt b/ext/mysqli/tests/mysqli_fetch_assoc_no_alias_utf8.phpt
index 1d7e38d6c10e..8ab3443dde14 100644
--- a/ext/mysqli/tests/mysqli_fetch_assoc_no_alias_utf8.phpt
+++ b/ext/mysqli/tests/mysqli_fetch_assoc_no_alias_utf8.phpt
@@ -42,7 +42,7 @@ mysqli
     }
 
     /* some cyrillic (utf8) comes here */
-    if (!$res = mysqli_query($link, "SET NAMES UTF8")) {
+    if (false === mysqli_query($link, "SET NAMES UTF8")) {
         printf("[001] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
 
@@ -53,16 +53,16 @@ mysqli
     var_dump(mysqli_fetch_assoc($res));
     mysqli_free_result($res);
 
-    if (!$res = mysqli_query($link, "CREATE TABLE автори_на_mysqlnd (id integer not null auto_increment primary key, име varchar(20) character set ucs2, фамилия varchar(20) character set utf8)")) {
+    if (false === mysqli_query($link, "CREATE TABLE автори_на_mysqlnd (id integer not null auto_increment primary key, име varchar(20) character set ucs2, фамилия varchar(20) character set utf8)")) {
         printf("[004] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
-    if (!$res = mysqli_query($link, "INSERT INTO автори_на_mysqlnd (име, фамилия) VALUES ('Андрей', 'Христов'), ('Георг', 'Рихтер'), ('Улф','Вендел')")) {
+    if (false === mysqli_query($link, "INSERT INTO автори_на_mysqlnd (име, фамилия) VALUES ('Андрей', 'Христов'), ('Георг', 'Рихтер'), ('Улф','Вендел')")) {
         printf("[005] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
-    if (!$res = mysqli_query($link, "INSERT INTO автори_на_mysqlnd (име, фамилия) VALUES ('Andrey', 'Hristov'), ('Georg', 'Richter'), ('Ulf','Wendel')")) {
+    if (false === mysqli_query($link, "INSERT INTO автори_на_mysqlnd (име, фамилия) VALUES ('Andrey', 'Hristov'), ('Georg', 'Richter'), ('Ulf','Wendel')")) {
         printf("[006] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
-    if (!$res = mysqli_query($link, "INSERT INTO автори_на_mysqlnd (име, фамилия) VALUES ('安德烈', 'Hristov'), ('格奥尔', 'Richter'), ('乌尔夫','Wendel')")) {
+    if (false === mysqli_query($link, "INSERT INTO автори_на_mysqlnd (име, фамилия) VALUES ('安德烈', 'Hristov'), ('格奥尔', 'Richter'), ('乌尔夫','Wendel')")) {
         printf("[007] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
 
@@ -75,7 +75,7 @@ mysqli
     }
     mysqli_free_result($res);
 
-    if (!$res = mysqli_query($link, "DROP TABLE автори_на_mysqlnd")) {
+    if (false === mysqli_query($link, "DROP TABLE автори_на_mysqlnd")) {
         printf("[010] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
 
diff --git a/ext/mysqli/tests/mysqli_fetch_field_flags.phpt b/ext/mysqli/tests/mysqli_fetch_field_flags.phpt
index 53eb3e691694..935defa484d2 100644
--- a/ext/mysqli/tests/mysqli_fetch_field_flags.phpt
+++ b/ext/mysqli/tests/mysqli_fetch_field_flags.phpt
@@ -187,7 +187,7 @@ mysqli_close($link);
     $column_def = array('col1 CHAR(1)', 'col2 CHAR(2)','INDEX idx_col1_col2(col1, col2)');
     $expected_flags = array('col1' => 'MULTIPLE_KEY PART_KEY', 'col2' => 'PART_KEY');
     $create = 'CREATE TABLE test(id INT, ';
-    foreach ($column_def as $k => $v) {
+    foreach ($column_def as $v) {
         $create .= sprintf('%s, ', $v);
     }
     $create = sprintf('%s)', substr($create, 0, -2));
@@ -198,7 +198,7 @@ mysqli_close($link);
                 mysqli_errno($link), mysqli_error($link));
         }
         // id column - skip it
-        $field = mysqli_fetch_field($res);
+        mysqli_fetch_field($res);
         while ($field = mysqli_fetch_field($res)) {
             if (!isset($expected_flags[$field->name])) {
                 printf("[010] Found unexpected field '%s'\n", $field->name);
diff --git a/ext/mysqli/tests/mysqli_fetch_lengths.phpt b/ext/mysqli/tests/mysqli_fetch_lengths.phpt
index 8a31ae25af3e..39d7cb861d29 100644
--- a/ext/mysqli/tests/mysqli_fetch_lengths.phpt
+++ b/ext/mysqli/tests/mysqli_fetch_lengths.phpt
@@ -9,13 +9,12 @@ require_once 'skipifconnectfailure.inc';
 --FILE--
 <?php
     require 'table.inc';
-    $mysqli = $link;
     if (!$res = mysqli_query($link, "SELECT id, label FROM test ORDER BY id LIMIT 1")) {
         printf("[003] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
 
     var_dump(mysqli_fetch_lengths($res));
-    while ($row = mysqli_fetch_assoc($res))
+    while (mysqli_fetch_assoc($res))
         var_dump(mysqli_fetch_lengths($res));
     var_dump(mysqli_fetch_lengths($res));
 
diff --git a/ext/mysqli/tests/mysqli_fetch_lengths_oo.phpt b/ext/mysqli/tests/mysqli_fetch_lengths_oo.phpt
index 980558e10829..df04e877d59b 100644
--- a/ext/mysqli/tests/mysqli_fetch_lengths_oo.phpt
+++ b/ext/mysqli/tests/mysqli_fetch_lengths_oo.phpt
@@ -15,7 +15,7 @@ require_once 'skipifconnectfailure.inc';
     }
 
     var_dump($res->lengths);
-    while ($row = $res->fetch_assoc())
+    while ($res->fetch_assoc())
         var_dump($res->lengths);
     var_dump($res->lengths);
 
diff --git a/ext/mysqli/tests/mysqli_fetch_object.phpt b/ext/mysqli/tests/mysqli_fetch_object.phpt
index e6ab9245152f..28e945db52f6 100644
--- a/ext/mysqli/tests/mysqli_fetch_object.phpt
+++ b/ext/mysqli/tests/mysqli_fetch_object.phpt
@@ -122,7 +122,7 @@ require_once 'skipifconnectfailure.inc';
     var_dump($obj = new mysqli_fetch_object_private_constructor(1, 2));
     This does not fail.
     */
-    $obj = mysqli_fetch_object($res, 'mysqli_fetch_object_private_constructor', array('a', 'b'));
+    mysqli_fetch_object($res, 'mysqli_fetch_object_private_constructor', array('a', 'b'));
     mysqli_free_result($res);
 
     try {
diff --git a/ext/mysqli/tests/mysqli_get_charset.phpt b/ext/mysqli/tests/mysqli_get_charset.phpt
index 0bc49bab8abc..14f655f8b0b2 100644
--- a/ext/mysqli/tests/mysqli_get_charset.phpt
+++ b/ext/mysqli/tests/mysqli_get_charset.phpt
@@ -24,13 +24,9 @@ require_once 'skipifconnectfailure.inc';
 
     if (!$res = mysqli_query($link, $sql = sprintf("SHOW CHARACTER SET LIKE '%s'", $character_set_connection)))
         printf("[009] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
-    $tmp = mysqli_fetch_assoc($res);
-    if (empty($tmp))
+    if (!mysqli_fetch_assoc($res))
         printf("[010] Cannot fetch Maxlen and/or Comment, test will fail: $sql\n");
 
-    $maxlen = (isset($tmp['Maxlen'])) ? $tmp['Maxlen'] : '';
-    $comment = (isset($tmp['Description'])) ? $tmp['Description'] : '';
-
     if (!$res = mysqli_query($link, sprintf("SHOW COLLATION LIKE '%s'", $collation_connection)))
         printf("[011] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     $tmp = mysqli_fetch_assoc($res);
diff --git a/ext/mysqli/tests/mysqli_get_client_stats.phpt b/ext/mysqli/tests/mysqli_get_client_stats.phpt
index 90823854d41f..17900c5ad609 100644
--- a/ext/mysqli/tests/mysqli_get_client_stats.phpt
+++ b/ext/mysqli/tests/mysqli_get_client_stats.phpt
@@ -85,7 +85,7 @@ mysqli.allow_local_infile=1
 
     var_dump($info);
 
-    if (!$link = my_mysqli_connect($host, $user, $passwd, $db, $port, $socket)) {
+    if (false === my_mysqli_connect($host, $user, $passwd, $db, $port, $socket)) {
         printf("[003] Cannot connect to the server using host=%s, user=%s, passwd=***, dbname=%s, port=%s, socket=%s\n",
             $host, $user, $db, $port, $socket);
         exit(1);
@@ -243,7 +243,7 @@ mysqli.allow_local_infile=1
     mysqli_get_client_stats_assert_eq('rows_fetched_from_client_normal_unbuffered', $info, $expected, $test_counter);
     mysqli_get_client_stats_assert_eq('bytes_received_real_data_normal', $info, $expected, $test_counter);
 
-    while ($row = mysqli_fetch_assoc($res))
+    while (mysqli_fetch_assoc($res))
         ;
     mysqli_free_result($res);
 
@@ -270,7 +270,7 @@ mysqli.allow_local_infile=1
             ++$test_counter, mysqli_errno($link), mysqli_error($link));
 
     for ($i = 0; $i < $num_rows - 1; $i++)
-        $row = mysqli_fetch_assoc($res);
+        mysqli_fetch_assoc($res);
 
     $expected['rows_fetched_from_server_normal'] = (string)($expected['rows_fetched_from_server_normal'] + $num_rows - 1);
     $expected['rows_fetched_from_client_normal_unbuffered'] = (string)($expected['rows_fetched_from_client_normal_unbuffered'] + $num_rows - 1);
@@ -551,7 +551,7 @@ mysqli.allow_local_infile=1
             mysqli_errno($link), mysqli_error($link));
 
     $rows = 0;
-    while ($row = mysqli_fetch_assoc($res))
+    while (mysqli_fetch_assoc($res))
         $rows++;
 
     if (0 == $rows)
@@ -617,7 +617,6 @@ mysqli.allow_local_infile=1
                 ++$test_counter, gettype($new_info), $new_info);
         mysqli_get_client_stats_assert_eq('non_result_set_queries', $new_info, (string)($info['non_result_set_queries'] + 2), $test_counter, 'DROP INDEX');
     }
-    $info = $new_info;
 
     // RENAME TABLE
     if (!mysqli_query($link, "DROP TABLE IF EXISTS client_stats_test"))
@@ -640,7 +639,6 @@ mysqli.allow_local_infile=1
         mysqli_get_client_stats_assert_eq('non_result_set_queries', $new_info, (string)($info['non_result_set_queries'] + 1), $test_counter, 'RENAME TABLE');
 
     }
-    $info = $new_info;
 
     if (!mysqli_query($link, "DROP TABLE IF EXISTS non_result_set_queries_test"))
         printf("[%03d] Cleanup, DROP TABLE failed, [%d] %s\n", ++$test_counter,
@@ -675,7 +673,6 @@ mysqli.allow_local_infile=1
             printf("[%03d] Expecting array/any_non_empty, got %s/%s\n",
                 ++$test_counter, gettype($new_info), $new_info);
         mysqli_get_client_stats_assert_eq('non_result_set_queries', $new_info, (string)($info['non_result_set_queries'] + 1), $test_counter, 'CREATE DATABASE');
-        $info = $new_info;
 
         if (!mysqli_query($link, "CREATE DATABASE mysqli_get_client_stats_"))
             printf("[%03d] CREATE DATABASE failed, [%d] %s\n", ++$test_counter,
@@ -693,7 +690,6 @@ mysqli.allow_local_infile=1
             printf("[%03d] Expecting array/any_non_empty, got %s/%s\n",
                 ++$test_counter, gettype($new_info), $new_info);
         mysqli_get_client_stats_assert_eq('non_result_set_queries', $new_info, (string)($info['non_result_set_queries'] + 1), $test_counter, 'DROP DATABASE');
-        $info = $new_info;
     }
 
     // CREATE SERVER, ALTER SERVER, DROP SERVER
@@ -812,7 +808,7 @@ mysqli.allow_local_infile=1
     mysqli_get_client_stats_assert_eq('non_result_set_queries', $new_info, (string)($info['non_result_set_queries'] + 1), $test_counter, 'DELETE');
     $info = $new_info;
 
-    if (!$res = mysqli_query($link, "TRUNCATE TABLE test"))
+    if (false === mysqli_query($link, "TRUNCATE TABLE test"))
         printf("[%03d] TRUNCATE failed, [%d] %s\n", ++$test_counter,
             mysqli_errno($link), mysqli_error($link));
 
@@ -854,7 +850,7 @@ mysqli.allow_local_infile=1
         printf("[%03d] Cannot insert new records, [%d] %s\n", ++$test_counter,
             mysqli_errno($link), mysqli_error($link));
 
-    if (!$res = mysqli_real_query($link, "SELECT id, label FROM test ORDER BY id"))
+    if (false === mysqli_real_query($link, "SELECT id, label FROM test ORDER BY id"))
         printf("[%03d] Cannot SELECT with mysqli_real_query(), [%d] %s\n", ++$test_counter,
             mysqli_errno($link), mysqli_error($link));
 
@@ -862,7 +858,7 @@ mysqli.allow_local_infile=1
         printf("[%03d] mysqli_use_result() failed, [%d] %s\n", ++$test_counter,
             mysqli_errno($link), mysqli_error($link));
 
-    while ($row = mysqli_fetch_assoc($res))
+    while (mysqli_fetch_assoc($res))
         ;
     mysqli_free_result($res);
     if (!is_array($new_info = mysqli_get_client_stats()) || empty($new_info))
@@ -871,7 +867,7 @@ mysqli.allow_local_infile=1
     mysqli_get_client_stats_assert_eq('unbuffered_sets', $new_info, (string)($info['unbuffered_sets'] + 1), $test_counter, 'mysqli_use_result()');
     $info = $new_info;
 
-    if (!$res = mysqli_real_query($link, "SELECT id, label FROM test ORDER BY id"))
+    if (false === mysqli_real_query($link, "SELECT id, label FROM test ORDER BY id"))
         printf("[%03d] Cannot SELECT with mysqli_real_query() II, [%d] %s\n", ++$test_counter,
             mysqli_errno($link), mysqli_error($link));
 
@@ -879,7 +875,7 @@ mysqli.allow_local_infile=1
         printf("[%03d] mysqli_use_result() failed, [%d] %s\n", ++$test_counter,
             mysqli_errno($link), mysqli_error($link));
 
-    while ($row = mysqli_fetch_assoc($res))
+    while (mysqli_fetch_assoc($res))
         ;
     mysqli_free_result($res);
     if (!is_array($new_info = mysqli_get_client_stats()) || empty($new_info))
diff --git a/ext/mysqli/tests/mysqli_get_client_stats_skipped.phpt b/ext/mysqli/tests/mysqli_get_client_stats_skipped.phpt
index aaf409885913..a302e0bbf999 100644
--- a/ext/mysqli/tests/mysqli_get_client_stats_skipped.phpt
+++ b/ext/mysqli/tests/mysqli_get_client_stats_skipped.phpt
@@ -29,7 +29,7 @@ require_once 'skipifconnectfailure.inc';
 
     /* fetch all rows but the last one */
     for ($i = 0; $i < $num_rows - 1; $i++)
-        $row = mysqli_fetch_assoc($res);
+        mysqli_fetch_assoc($res);
 
     /* enforce implicit cleaning of the wire and skipping the last row */
     mysqli_free_result($res);
diff --git a/ext/mysqli/tests/mysqli_get_warnings.phpt b/ext/mysqli/tests/mysqli_get_warnings.phpt
index 08831200648d..55db12d966a9 100644
--- a/ext/mysqli/tests/mysqli_get_warnings.phpt
+++ b/ext/mysqli/tests/mysqli_get_warnings.phpt
@@ -12,24 +12,12 @@ if (!$TEST_EXPERIMENTAL)
 <?php
     require_once 'connect.inc';
 
-    $tmp    = NULL;
-    $link   = NULL;
-
-    if (!is_null($tmp = @mysqli_get_warnings()))
-        printf("[001] Expecting NULL, got %s/%s\n", gettype($tmp), $tmp);
-
-    if (!is_null($tmp = @mysqli_get_warnings($link)))
-        printf("[002] Expecting NULL, got %s/%s\n", gettype($tmp), $tmp);
-
-    if (!is_null($tmp = @mysqli_get_warnings('')))
-        printf("[002] Expecting NULL, got %s/%s\n", gettype($tmp), $tmp);
-
     if (!$link = my_mysqli_connect($host, $user, $passwd, $db, $port, $socket)) {
         printf("[003] [%d] %s\n", mysqli_connect_errno(), mysqli_connect_error());
     }
 
     if (false !== ($tmp = mysqli_get_warnings($link))) {
-        printf("[004] Expecting boolean/false, got %s/%s\n", gettype($tmp), (is_object($tmp) ? var_dump($tmp, true) : $tmp));
+        printf("[004] Expecting boolean/false, got %s/%s\n", gettype($tmp), var_export($tmp, true));
     }
 
     if (!mysqli_query($link, "DROP TABLE IF EXISTS test"))
@@ -42,7 +30,7 @@ if (!$TEST_EXPERIMENTAL)
         printf("[007] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
     if (!is_object($warning = mysqli_get_warnings($link)) || 'mysqli_warning' != get_class($warning)) {
-        printf("[008] Expecting object/mysqli_warning, got %s/%s\n", gettype($tmp), (is_object($tmp) ? var_dump($tmp, true) : $tmp));
+        printf("[008] Expecting object/mysqli_warning, got %s/%s\n", gettype($tmp), (is_object($tmp) ? var_export($tmp, true) : $tmp));
     }
 
     if (!method_exists($warning, 'next'))
@@ -71,7 +59,7 @@ if (!$TEST_EXPERIMENTAL)
         printf("[016] Expecting 2 warnings, got %d warnings", $tmp);
 
     if (!is_object($warning = mysqli_get_warnings($link)) || 'mysqli_warning' != get_class($warning)) {
-        printf("[017] Expecting object/mysqli_warning, got %s/%s\n", gettype($tmp), (is_object($tmp) ? var_dump($tmp, true) : $tmp));
+        printf("[017] Expecting object/mysqli_warning, got %s/%s\n", gettype($tmp), (is_object($tmp) ? var_export($tmp, true) : $tmp));
     }
 
     if (true !== ($tmp = $warning->next()))
@@ -129,7 +117,7 @@ if (!$TEST_EXPERIMENTAL)
     if (3 != $i)
         printf("[034] Expecting three warnings, got %d warnings\n", $i);
 
-    $stmt = mysqli_stmt_init();
+    $stmt = mysqli_stmt_init($mysqli);
     $warning = new mysqli_warning($stmt);
     if (false !== ($tmp = $warning->next()))
         printf("[035] Expecting boolean/false, got %s/%s\n", gettype($tmp), $tmp);
diff --git a/ext/mysqli/tests/mysqli_info.phpt b/ext/mysqli/tests/mysqli_info.phpt
index ce1d05507539..6b4c5be41a7d 100644
--- a/ext/mysqli/tests/mysqli_info.phpt
+++ b/ext/mysqli/tests/mysqli_info.phpt
@@ -11,43 +11,42 @@ mysqli.allow_local_infile=1
 --FILE--
 <?php
     require 'table.inc';
-    if (!$res = mysqli_query($link, "INSERT INTO test(id, label) VALUES (100, 'a')"))
+    if (false === mysqli_query($link, "INSERT INTO test(id, label) VALUES (100, 'a')"))
         printf("[003] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
     // NOTE: empty string, no multiple insert syntax
     if (!is_null($tmp = mysqli_info($link)) || ('' != $tmp))
         printf("[004] Expecting null, got %s/%s\n", gettype($tmp), $tmp);
 
-    if (!$res = mysqli_query($link, "INSERT INTO test(id, label) VALUES (101, 'a'), (102, 'b')"))
+    if (false === mysqli_query($link, "INSERT INTO test(id, label) VALUES (101, 'a'), (102, 'b')"))
         printf("[005] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
     if (!is_string($tmp = mysqli_info($link)) || ('' == $tmp))
         printf("[006] Expecting string/any_non_empty, got %s/%s\n", gettype($tmp), $tmp);
 
-    if (!$res = mysqli_query($link, 'INSERT INTO test(id, label) SELECT id + 200, label FROM test'))
+    if (false === mysqli_query($link, 'INSERT INTO test(id, label) SELECT id + 200, label FROM test'))
         printf("[007] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
     if (!is_string($tmp = mysqli_info($link)) || ('' == $tmp))
         printf("[008] Expecting string/any_non_empty, got %s/%s\n", gettype($tmp), $tmp);
 
-    if (!$res = mysqli_query($link, 'ALTER TABLE test MODIFY label CHAR(2)'))
+    if (false === mysqli_query($link, 'ALTER TABLE test MODIFY label CHAR(2)'))
         printf("[009] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
     if (!is_string($tmp = mysqli_info($link)) || ('' == $tmp))
         printf("[010] Expecting string/any_non_empty, got %s/%s\n", gettype($tmp), $tmp);
 
-    if (!$res = mysqli_query($link, "UPDATE test SET label = 'b' WHERE id >= 100"))
+    if (false === mysqli_query($link, "UPDATE test SET label = 'b' WHERE id >= 100"))
         printf("[011] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
     if (!is_string($tmp = mysqli_info($link)) || ('' == $tmp))
         printf("[012] Expecting string/any_non_empty, got %s/%s\n", gettype($tmp), $tmp);
 
-    if (!$res = mysqli_query($link, "SELECT 1"))
+    if (false === mysqli_query($link, "SELECT 1"))
         printf("[013] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
     if (!is_null($tmp = mysqli_info($link)) || ('' != $tmp))
         printf("[014] Expecting null, got %s/%s\n", gettype($tmp), $tmp);
-    mysqli_free_result($res);
 
     // NOTE: no LOAD DATA INFILE test
     if ($dir = sys_get_temp_dir()) {
diff --git a/ext/mysqli/tests/mysqli_insert_id.phpt b/ext/mysqli/tests/mysqli_insert_id.phpt
index 7a2add8eb31f..484bfc4b4d90 100644
--- a/ext/mysqli/tests/mysqli_insert_id.phpt
+++ b/ext/mysqli/tests/mysqli_insert_id.phpt
@@ -13,25 +13,24 @@ require_once 'skipifconnectfailure.inc';
     if (0 !== ($tmp = mysqli_insert_id($link)))
         printf("[003] Expecting int/0, got %s/%s\n", gettype($tmp), $tmp);
 
-    if (!$res = mysqli_query($link, "SELECT id, label FROM test ORDER BY id LIMIT 1")) {
+    if (false === mysqli_query($link, "SELECT id, label FROM test ORDER BY id LIMIT 1")) {
         printf("[004] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
     if (0 !== ($tmp = mysqli_insert_id($link)))
         printf("[005] Expecting int/0, got %s/%s\n", gettype($tmp), $tmp);
-    mysqli_free_result($res);
 
     // no auto_increment column
-    if (!$res = mysqli_query($link, "INSERT INTO test(id, label) VALUES (100, 'a')")) {
+    if (false === mysqli_query($link, "INSERT INTO test(id, label) VALUES (100, 'a')")) {
         printf("[006] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
     if (0 !== ($tmp = mysqli_insert_id($link)))
         printf("[007] Expecting int/0, got %s/%s\n", gettype($tmp), $tmp);
 
-    if (!$res = mysqli_query($link, "ALTER TABLE test MODIFY id INT NOT NULL AUTO_INCREMENT")) {
+    if (false === mysqli_query($link, "ALTER TABLE test MODIFY id INT NOT NULL AUTO_INCREMENT")) {
         printf("[008] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
 
-    if (!$res = mysqli_query($link, "INSERT INTO test(label) VALUES ('a')")) {
+    if (false === mysqli_query($link, "INSERT INTO test(label) VALUES ('a')")) {
         printf("[009] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
     if (($last_id = mysqli_insert_id($link)) <= 0)
@@ -101,13 +100,13 @@ require_once 'skipifconnectfailure.inc';
         mysqli_query($link, "UNLOCK TABLE test");
     }
 
-    if (!$res = mysqli_query($link, "INSERT INTO test(id, label) VALUES (1000, 'a')")) {
+    if (false === mysqli_query($link, "INSERT INTO test(id, label) VALUES (1000, 'a')")) {
         printf("[020] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
     if (1000 !== ($tmp = mysqli_insert_id($link)))
         printf("[021] Expecting int/1000, got %s/%s\n", gettype($tmp), $tmp);
 
-    if (!$res = mysqli_query($link, "INSERT INTO test(label) VALUES ('b'), ('c')")) {
+    if (false === mysqli_query($link, "INSERT INTO test(label) VALUES ('b'), ('c')")) {
         printf("[022] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
     }
     if (1000 >= ($tmp = mysqli_insert_id($link)))
diff --git a/ext/mysqli/tests/mysqli_insert_packet_overflow.phpt b/ext/mysqli/tests/mysqli_insert_packet_overflow.phpt
index d8cdd633121e..feb890a869e4 100644
--- a/ext/mysqli/tests/mysqli_insert_packet_overflow.phpt
+++ b/ext/mysqli/tests/mysqli_insert_packet_overflow.phpt
@@ -4,19 +4,7 @@ INSERT and packet overflow
 mysqli
 --SKIPIF--
 <?php
-require_once 'connect.inc';
-
-if (!$link = @my_mysqli_connect($host, $user, $passwd, $db, $port, $socket))
-    die(sprintf("SKIP [%d] %s\n", mysqli_connect_errno(), mysqli_connect_error()));
-
-$max_len = pow(2, 24);
-if (!$res = mysqli_query($link, "SHOW GLOBAL VARIABLES LIKE 'max_allowed_packet'"))
-    die(sprintf("SKIP [%d] %s\n", mysqli_errno($link), mysqli_error($link)));
-
-if (!mysqli_query($link, "SET NAMES 'latin1'"))
-    die(sprintf("SKIP [%d] %s\n", mysqli_errno($link), mysqli_error($link)));
-
-mysqli_close($link);
+require_once 'skipifconnectfailure.inc';
 ?>
 --INI--
 memory_limit=256M
diff --git a/ext/mysqli/tests/mysqli_kill.phpt b/ext/mysqli/tests/mysqli_kill.phpt
index 19e34caa19f4..0ed58d2ad04a 100644
--- a/ext/mysqli/tests/mysqli_kill.phpt
+++ b/ext/mysqli/tests/mysqli_kill.phpt
@@ -19,12 +19,10 @@ require_once 'skipifconnectfailure.inc';
     if (!$thread_id = mysqli_thread_id($link))
         printf("[004] Cannot determine thread id, [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
-    $tmp = mysqli_kill($link, $thread_id);
-    if (!is_bool($tmp))
-        printf("[005] Expecting boolean/any, got %s/%s\n", gettype($tmp), $tmp);
+    mysqli_kill($link, $thread_id);
 
     if ($res = mysqli_query($link, "SELECT id FROM test LIMIT 1"))
-        pintf("[006] Expecting boolean/false, got %s/%s\n", gettype($res), $res);
+        printf("[006] Expecting boolean/false, got %s/%s\n", gettype($res), $res);
 
     var_dump($error = mysqli_error($link));
     if (!is_string($error) || ('' === $error))
diff --git a/ext/mysqli/tests/mysqli_more_results.phpt b/ext/mysqli/tests/mysqli_more_results.phpt
index 5c1f453cb9b0..4cf99b801eb4 100644
--- a/ext/mysqli/tests/mysqli_more_results.phpt
+++ b/ext/mysqli/tests/mysqli_more_results.phpt
@@ -39,7 +39,7 @@ require_once 'skipifconnectfailure.inc';
         // NOTE: if you use mysqli_use_result() with mysqli_more_results() or any other info function,
         // you must fetch all rows before you can loop to the next result set!
         // See also the MySQL Reference Manual: mysql_use_result()
-        while ($row = mysqli_fetch_array($res))
+        while (mysqli_fetch_array($res))
             ;
         mysqli_free_result($res);
         if (mysqli_more_results($link))
diff --git a/ext/mysqli/tests/mysqli_multi_query.phpt b/ext/mysqli/tests/mysqli_multi_query.phpt
index 618ffe2085e3..69950aec4c04 100644
--- a/ext/mysqli/tests/mysqli_multi_query.phpt
+++ b/ext/mysqli/tests/mysqli_multi_query.phpt
@@ -19,7 +19,7 @@ require_once 'skipifconnectfailure.inc';
     $i = 0;
     do {
         $res = mysqli_store_result($link);
-        while ($row = mysqli_fetch_array($res))
+        while (mysqli_fetch_array($res))
             ;
         mysqli_free_result($res);
         $i++;
@@ -33,7 +33,7 @@ require_once 'skipifconnectfailure.inc';
     $i = 0;
     while (mysqli_next_result($link) && ($res = mysqli_store_result($link))) {
 
-        while ($row = mysqli_fetch_array($res))
+        while (mysqli_fetch_array($res))
             ;
         mysqli_free_result($res);
         printf("%d/%d\n", $i, mysqli_insert_id($link));
@@ -46,7 +46,7 @@ require_once 'skipifconnectfailure.inc';
 
     $i = 0;
     while (mysqli_next_result($link) && ($res = mysqli_store_result($link))) {
-        while ($row = mysqli_fetch_array($res))
+        while (mysqli_fetch_array($res))
             $i++;
         mysqli_free_result($res);
     }
@@ -77,7 +77,7 @@ require_once 'skipifconnectfailure.inc';
                     printf("[015 - %d] [%d] %s\n", $res_num, mysqli_errno($link), mysqli_error($link));
 
                 if (count($lengths) != 2)
-                    printf("[016 - %d] Expecting 2 column lengths got %d [%d] %s\n", $res_num, count($lengths));
+                    printf("[016 - %d] Expecting 2 column lengths got %d\n", $res_num, count($lengths));
 
                 foreach ($lengths as $k => $length)
                     if ($length <= 0)
@@ -87,7 +87,7 @@ require_once 'skipifconnectfailure.inc';
         }
 
         if ($num_rows != 1)
-            printf("[018 - %d] Expecting 1 row, got %d rows\n", $num_rows);
+            printf("[018 - %d] Expecting 1 row, got %d rows\n", $res_num, $num_rows);
 
         $res_num++;
 
diff --git a/ext/mysqli/tests/mysqli_mysqlnd_read_timeout.phpt b/ext/mysqli/tests/mysqli_mysqlnd_read_timeout.phpt
index 59a8719cbbe6..11049dfa09ec 100644
--- a/ext/mysqli/tests/mysqli_mysqlnd_read_timeout.phpt
+++ b/ext/mysqli/tests/mysqli_mysqlnd_read_timeout.phpt
@@ -18,7 +18,7 @@ mysqlnd.net_read_timeout=1
         printf("[001] Connect failed, [%d] %s\n", mysqli_connect_errno(), mysqli_connect_error());
     }
 
-    if (!$res = mysqli_query($link, "SELECT SLEEP(5)"))
+    if (false === mysqli_query($link, "SELECT SLEEP(5)"))
         printf("[002] [%d] %s\n",  mysqli_errno($link), mysqli_error($link));
 
     mysqli_close($link);
diff --git a/ext/mysqli/tests/mysqli_no_reconnect.phpt b/ext/mysqli/tests/mysqli_no_reconnect.phpt
index d74f57557b22..929cb1dcd0c2 100644
--- a/ext/mysqli/tests/mysqli_no_reconnect.phpt
+++ b/ext/mysqli/tests/mysqli_no_reconnect.phpt
@@ -67,7 +67,7 @@ require_once 'skipifconnectfailure.inc';
     if (false !== @mysqli_ping($link))
         printf("[010] Reconnect should not have happened");
 
-    if ($res = @mysqli_query($link, "SELECT DATABASE() as _dbname"))
+    if (@mysqli_query($link, "SELECT DATABASE() as _dbname"))
         printf("[011] Executing a query should not be possible, connection should be closed, [%d] %s\n",
             mysqli_errno($link), mysqli_error($link));
 
@@ -111,7 +111,7 @@ require_once 'skipifconnectfailure.inc';
     if (false !== ($tmp = @mysqli_ping($link)))
         printf("[016] Expecting boolean/false got %s/%s\n", gettype($tmp), $tmp);
 
-    if ($res = @mysqli_query($link, "SELECT DATABASE() as _dbname"))
+    if (@mysqli_query($link, "SELECT DATABASE() as _dbname"))
         printf("[017] Running a query should not be possible, connection should be gone, [%d] %s\n",
             mysqli_errno($link), mysqli_error($link));
 
diff --git a/ext/mysqli/tests/mysqli_num_fields.phpt b/ext/mysqli/tests/mysqli_num_fields.phpt
index 3022a8911524..cd24d90085c1 100644
--- a/ext/mysqli/tests/mysqli_num_fields.phpt
+++ b/ext/mysqli/tests/mysqli_num_fields.phpt
@@ -10,7 +10,7 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require 'table.inc';
 
-    function func_test_mysqli_num_fields($link, $query, $expected, $offset, $test_free = false) {
+    function func_test_mysqli_num_fields(mysqli $link, string $query, int $expected, int $offset) {
 
         if (!($res = mysqli_query($link, $query))) {
             printf("[%03d] [%d] %s\n", $offset, mysqli_errno($link), mysqli_error($link));
@@ -34,7 +34,7 @@ require_once 'skipifconnectfailure.inc';
     func_test_mysqli_num_fields($link, "SELECT 1 AS a", 1, 5);
     func_test_mysqli_num_fields($link, "SELECT id, label FROM test", 2, 10);
     func_test_mysqli_num_fields($link, "SELECT 1 AS a, NULL AS b, 'foo' AS c", 3, 15);
-    func_test_mysqli_num_fields($link, "SELECT id FROM test", 1, 20, true);
+    func_test_mysqli_num_fields($link, "SELECT id FROM test", 1, 20);
 
     mysqli_close($link);
 
diff --git a/ext/mysqli/tests/mysqli_num_rows.phpt b/ext/mysqli/tests/mysqli_num_rows.phpt
index a625669fb0e4..a0c74ab2266e 100644
--- a/ext/mysqli/tests/mysqli_num_rows.phpt
+++ b/ext/mysqli/tests/mysqli_num_rows.phpt
@@ -10,7 +10,7 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require 'table.inc';
 
-    function func_test_mysqli_num_rows($link, $query, $expected, $offset, $test_free = false) {
+    function func_test_mysqli_num_rows(mysqli $link, string $query, int|null $expected, int $offset) {
 
         if (!$res = mysqli_query($link, $query, MYSQLI_STORE_RESULT)) {
             printf("[%03d] [%d] %s\n", $offset, mysqli_errno($link), mysqli_error($link));
@@ -36,7 +36,7 @@ require_once 'skipifconnectfailure.inc';
     func_test_mysqli_num_rows($link, "SELECT 1 AS a", 1, 5);
     func_test_mysqli_num_rows($link, "SHOW VARIABLES LIKE '%nixnutz%'", 0, 10);
     func_test_mysqli_num_rows($link, "INSERT INTO test(id, label) VALUES (100, 'z')", NULL, 15);
-    func_test_mysqli_num_rows($link, "SELECT id FROM test LIMIT 2", 2, 20, true);
+    func_test_mysqli_num_rows($link, "SELECT id FROM test LIMIT 2", 2, 20);
 
     if ($res = mysqli_query($link, 'SELECT COUNT(id) AS num FROM test')) {
 
@@ -53,7 +53,7 @@ require_once 'skipifconnectfailure.inc';
 
     if ($res = mysqli_query($link, 'SELECT id FROM test', MYSQLI_USE_RESULT)) {
 
-        $row = mysqli_fetch_row($res);
+        mysqli_fetch_row($res);
         try {
             var_dump(mysqli_num_rows($res));
         } catch (\Error $e) {
diff --git a/ext/mysqli/tests/mysqli_pam_sha256_public_key_option_invalid.phpt b/ext/mysqli/tests/mysqli_pam_sha256_public_key_option_invalid.phpt
index 5c4a60cd0066..70e18584326c 100644
--- a/ext/mysqli/tests/mysqli_pam_sha256_public_key_option_invalid.phpt
+++ b/ext/mysqli/tests/mysqli_pam_sha256_public_key_option_invalid.phpt
@@ -101,9 +101,10 @@ echo "nocache";
             return false;
         }
 
-        if (!$res = $link->query("SELECT id FROM test WHERE id = 1"))
+        if (!$res = $link->query("SELECT id FROM test WHERE id = 1")) {
             printf("[%03d + 003] [%d] %s\n", $offset, $link->errno, $link->error);
             return false;
+        }
 
         if (!$row = mysqli_fetch_assoc($res)) {
             printf("[%03d + 004] [%d] %s\n", $offset, $link->errno, $link->error);
diff --git a/ext/mysqli/tests/mysqli_pconn_max_links.phpt b/ext/mysqli/tests/mysqli_pconn_max_links.phpt
index 4cf28f6819e0..88b89228e111 100644
--- a/ext/mysqli/tests/mysqli_pconn_max_links.phpt
+++ b/ext/mysqli/tests/mysqli_pconn_max_links.phpt
@@ -29,7 +29,7 @@ mysqli
         die("skip GRANT failed");
     }
 
-    if (!($link_pcontest = @my_mysqli_connect($host, 'pcontest', 'pcontest', $db, $port, $socket))) {
+    if (!@my_mysqli_connect($host, 'pcontest', 'pcontest', $db, $port, $socket)) {
         mysqli_query($link, 'REVOKE ALL PRIVILEGES, GRANT OPTION FROM pcontest');
         mysqli_query($link, 'REVOKE ALL PRIVILEGES, GRANT OPTION FROM pcontest@localhost');
         mysqli_query($link, 'DROP USER pcontest@localhost');
@@ -56,7 +56,7 @@ mysqli.rollback_on_cached_plink=1
         !mysqli_query($link, sprintf("GRANT SELECT ON TABLE %s.test TO pcontest@'%%'", $db)) ||
         !mysqli_query($link, sprintf("GRANT SELECT ON TABLE %s.test TO pcontest@'localhost'", $db))) {
         printf("[000] Init failed, [%d] %s\n",
-            mysqli_errno($plink), mysqli_error($plink));
+            mysqli_errno($link), mysqli_error($link));
     }
 
     try {
@@ -129,9 +129,10 @@ mysqli.rollback_on_cached_plink=1
     var_dump(mysqli_get_links_stats());
 
     // this fails and we have 0 (<= $num_plinks) connections
+    // Do not remove the variable assignment as it is important that we have 2 active connections
     if ($plink = @my_mysqli_connect('p:' . $host, 'pcontest', 'pcontest', $db, $port, $socket))
         printf("[010] Can connect using the old password, [%d] %s\n",
-            mysqli_connect_errno($link), mysqli_connect_error($link));
+            mysqli_connect_errno(), mysqli_connect_error());
 
     echo "After second pconnect:";
     var_dump(mysqli_get_links_stats());
@@ -168,6 +169,7 @@ mysqli.rollback_on_cached_plink=1
     mysqli_free_result($res);
     var_dump($row);
 
+    // Do not remove the variable assignment as it is important that we have 2 active connections
     if ($plink2 = my_mysqli_connect('p:' . $host, 'pcontest', 'newpass', $db, $port, $socket)) {
         printf("[015] Can open more persistent connections than allowed, [%d] %s\n",
             mysqli_connect_errno(), mysqli_connect_error());
diff --git a/ext/mysqli/tests/mysqli_phpinfo.phpt b/ext/mysqli/tests/mysqli_phpinfo.phpt
index d4a464e99f16..6df4e82dfd54 100644
--- a/ext/mysqli/tests/mysqli_phpinfo.phpt
+++ b/ext/mysqli/tests/mysqli_phpinfo.phpt
@@ -46,7 +46,7 @@ require_once 'skipifconnectfailure.inc';
         'mysqli.allow_local_infile', 'mysqli.local_infile_directory',
         'mysqli.allow_persistent', 'mysqli.max_persistent'
     );
-    foreach ($expected as $k => $entry)
+    foreach ($expected as $entry)
         if (!stristr($phpinfo, $entry))
             printf("[010] Could not find entry for '%s'\n", $entry);
 
diff --git a/ext/mysqli/tests/mysqli_ping.phpt b/ext/mysqli/tests/mysqli_ping.phpt
index ef1a3e055969..626f2330dcb3 100644
--- a/ext/mysqli/tests/mysqli_ping.phpt
+++ b/ext/mysqli/tests/mysqli_ping.phpt
@@ -18,7 +18,7 @@ require_once 'skipifconnectfailure.inc';
     var_dump(mysqli_ping($link));
 
     // provoke an error to check if mysqli_ping resets it
-    $res = mysqli_query($link, 'SELECT * FROM unknown_table');
+    mysqli_query($link, 'SELECT * FROM unknown_table');
     if (!($errno = mysqli_errno($link)))
         printf("[003] Statement should have caused an error\n");
 
diff --git a/ext/mysqli/tests/mysqli_poll_mixing_insert_select.phpt b/ext/mysqli/tests/mysqli_poll_mixing_insert_select.phpt
index 30325aa044f2..f95bc99276e2 100644
--- a/ext/mysqli/tests/mysqli_poll_mixing_insert_select.phpt
+++ b/ext/mysqli/tests/mysqli_poll_mixing_insert_select.phpt
@@ -44,11 +44,11 @@ require_once 'skipifconnectfailure.inc';
     mysqli_close($link);
 
     $links = array();
-    for ($i = 0; $i < count($queries); $i++) {
+    foreach ($queries as $query) {
 
         $link = get_connection();
 
-        if (true !== ($tmp = mysqli_query($link, $queries[$i], MYSQLI_ASYNC |  MYSQLI_USE_RESULT)))
+        if (true !== ($tmp = mysqli_query($link, $query, MYSQLI_ASYNC |  MYSQLI_USE_RESULT)))
             printf("[002] Expecting true got %s/%s\n", gettype($tmp), var_export($tmp, true));
 
         // WARNING KLUDGE NOTE
@@ -57,7 +57,7 @@ require_once 'skipifconnectfailure.inc';
         usleep(20000);
 
         $links[mysqli_thread_id($link)] = array(
-            'query' => $queries[$i],
+            'query' => $query,
             'link' => $link,
             'processed' => false,
         );
@@ -66,7 +66,7 @@ require_once 'skipifconnectfailure.inc';
     $saved_errors = array();
     do {
         $poll_links = $poll_errors = $poll_reject = array();
-        foreach ($links as $thread_id => $link) {
+        foreach ($links as $link) {
             if (!$link['processed']) {
                 $poll_links[] = $link['link'];
                 $poll_errors[] = $link['link'];
@@ -93,7 +93,7 @@ require_once 'skipifconnectfailure.inc';
 
             if (is_object($res = mysqli_reap_async_query($link))) {
                 // result set object
-                while ($row = mysqli_fetch_assoc($res)) {
+                while (mysqli_fetch_assoc($res)) {
                     // eat up all results
                     ;
                 }
@@ -120,9 +120,9 @@ require_once 'skipifconnectfailure.inc';
         }
 
         if (!$res = mysqli_query($link['link'], 'SELECT * FROM test WHERE id = 100'))
-            printf("[005] Expecting true got %s/%s\n", gettype($tmp), var_export($tmp, true));
+            printf("[005] Expecting true got %s/%s\n", gettype($res), var_export($res, true));
         if (!$row = mysqli_fetch_row($res))
-            printf("[006] Expecting true got %s/%s\n", gettype($tmp), var_export($tmp, true));
+            printf("[006] Expecting true got %s/%s\n", gettype($row), var_export($row, true));
 
         mysqli_free_result($res);
     }
diff --git a/ext/mysqli/tests/mysqli_poll_reference.phpt b/ext/mysqli/tests/mysqli_poll_reference.phpt
index 8fcb9b2fbbac..93cdc77be400 100644
--- a/ext/mysqli/tests/mysqli_poll_reference.phpt
+++ b/ext/mysqli/tests/mysqli_poll_reference.phpt
@@ -42,7 +42,7 @@ if (mysqli_get_server_version($link) < 50012)
         // WARNING: All arrays point to the same object - this will give bogus results!
         // The behaviour is in line with stream_select(). Be warned, be careful.
         $links = $errors = $reject = array($mysqli1, $mysqli2);
-        if (0 == ($ready = mysqli_poll($links, $errors, $reject, 0, 50000))) {
+        if (0 == mysqli_poll($links, $errors, $reject, 0, 50000)) {
             continue;
         }
 
@@ -73,7 +73,7 @@ if (mysqli_get_server_version($link) < 50012)
         // WARNING: All arrays point to the same object - this will give bogus results!
         $links = $errors = array($mysqli1, $mysqli2);
         $reject = array($mysqli1, $mysqli2);
-        if (0 == ($ready = mysqli_poll($links, $errors, $reject, 0, 50000))) {
+        if (0 == mysqli_poll($links, $errors, $reject, 0, 50000)) {
             continue;
         }
         foreach ($links as $link) {
@@ -103,7 +103,7 @@ if (mysqli_get_server_version($link) < 50012)
         // WARNING: All arrays point to the same object - this will give bogus results!
         $links = array($mysqli1, $mysqli2);
         $errors = $reject = array($mysqli1, $mysqli2);
-        if (0 == ($ready = mysqli_poll($links, $errors, $reject, 0, 50000))) {
+        if (0 == mysqli_poll($links, $errors, $reject, 0, 50000)) {
             continue;
         }
         foreach ($links as $link) {
@@ -133,7 +133,7 @@ if (mysqli_get_server_version($link) < 50012)
             break;
         }
         $links = $errors = $reject = array($mysqli1, $mysqli2);
-        if (0 == ($ready = mysqli_poll($links, $errors, $reject, 0, 50000))) {
+        if (0 == mysqli_poll($links, $errors, $reject, 0, 50000)) {
             continue;
         }
         // WARNING: Due to the reference issue none of these should ever fire!
@@ -176,7 +176,7 @@ if (mysqli_get_server_version($link) < 50012)
         }
         $links = $errors = $reject = $all;
         ob_start();
-        if (0 == ($ready = mysqli_poll($links, $errors, $reject, 0, 50000))) {
+        if (0 == mysqli_poll($links, $errors, $reject, 0, 50000)) {
             $tmp = ob_get_contents();
             ob_end_clean();
             if ($tmp != '') {
@@ -193,7 +193,7 @@ if (mysqli_get_server_version($link) < 50012)
         }
     } while ($processed < 2);
 
-    $ready = mysqli_poll($links, $errors, $reject, 0, 50000);
+    mysqli_poll($links, $errors, $reject, 0, 50000);
     mysqli_close($mysqli1);
     mysqli_close($mysqli2);
 
diff --git a/ext/mysqli/tests/mysqli_prepare_no_object.phpt b/ext/mysqli/tests/mysqli_prepare_no_object.phpt
index c488cbe50591..7ef3728535fe 100644
--- a/ext/mysqli/tests/mysqli_prepare_no_object.phpt
+++ b/ext/mysqli/tests/mysqli_prepare_no_object.phpt
@@ -11,11 +11,11 @@ require_once 'skipifconnectfailure.inc';
     require 'table.inc';
 
     if (false !== ($tmp = mysqli_prepare($link, false)))
-        printf("[001] Expecting boolean/false, got %s/%s\n", gettype($tmp), (is_object($tmp) ? var_dump($tmp, true) : $tmp));
+        printf("[001] Expecting boolean/false, got %s/%s\n", gettype($tmp), var_export($tmp, true));
     printf("a) [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
     if (false !== ($tmp = mysqli_prepare($link, '')))
-        printf("[002] Expecting boolean/false, got %s/%s\n", gettype($tmp), (is_object($tmp) ? var_dump($tmp, true) : $tmp));
+        printf("[002] Expecting boolean/false, got %s/%s\n", gettype($tmp), var_export($tmp, true));
     printf("b) [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
     mysqli_close($link);
@@ -23,11 +23,11 @@ require_once 'skipifconnectfailure.inc';
     $mysqli = new my_mysqli($host, $user, $passwd, $db, $port, $socket);
 
     if (false !== ($tmp = $mysqli->prepare(false)))
-        printf("[004] Expecting boolean/false, got %s/%s\n", gettype($tmp), (is_object($tmp) ? var_dump($tmp, true) : $tmp));
+        printf("[004] Expecting boolean/false, got %s/%s\n", gettype($tmp), var_export($tmp, true));
     printf("c) [%d] %s\n", $mysqli->errno, $mysqli->error);
 
     if (false !== ($tmp = $mysqli->prepare('')))
-        printf("[005] Expecting boolean/false, got %s/%s\n", gettype($tmp), (is_object($tmp) ? var_dump($tmp, true) : $tmp));
+        printf("[005] Expecting boolean/false, got %s/%s\n", gettype($tmp), var_export($tmp, true));
     printf("c) [%d] %s\n", $mysqli->errno, $mysqli->error);
 
     print "done!";
diff --git a/ext/mysqli/tests/mysqli_query.phpt b/ext/mysqli/tests/mysqli_query.phpt
index adb416708fc0..640dbacaaf2c 100644
--- a/ext/mysqli/tests/mysqli_query.phpt
+++ b/ext/mysqli/tests/mysqli_query.phpt
@@ -45,7 +45,7 @@ require_once 'skipifconnectfailure.inc';
         // let's try to play with stored procedures
         mysqli_query($link, 'DROP PROCEDURE IF EXISTS p');
         if (mysqli_query($link, 'CREATE PROCEDURE p(OUT ver_param VARCHAR(25)) BEGIN SELECT VERSION() INTO ver_param; END;')) {
-            $res = mysqli_query($link, 'CALL p(@version)');
+            mysqli_query($link, 'CALL p(@version)');
             $res = mysqli_query($link, 'SELECT @version AS p_version');
 
             $tmp = mysqli_fetch_assoc($res);
diff --git a/ext/mysqli/tests/mysqli_query_iterators.phpt b/ext/mysqli/tests/mysqli_query_iterators.phpt
index ea48fa864db9..91acc529f90c 100644
--- a/ext/mysqli/tests/mysqli_query_iterators.phpt
+++ b/ext/mysqli/tests/mysqli_query_iterators.phpt
@@ -25,7 +25,8 @@ require_once 'skipifconnectfailure.inc';
         mysqli_free_result($res);
         try {
             foreach ($res as $row) {
-                $row;
+                echo "Iterating over a closed result set should not work\n";
+                var_dump($row);
             }
         } catch (Error $exception) {
             echo $exception->getMessage() . "\n";
diff --git a/ext/mysqli/tests/mysqli_query_stored_proc.phpt b/ext/mysqli/tests/mysqli_query_stored_proc.phpt
index dbd22fbb38f4..e9590e4a5540 100644
--- a/ext/mysqli/tests/mysqli_query_stored_proc.phpt
+++ b/ext/mysqli/tests/mysqli_query_stored_proc.phpt
@@ -107,8 +107,7 @@ END;')) {
         if (!$res = mysqli_query($link, 'SELECT @version as _vers'))
             printf("[014] Cannot fetch user variable, [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
-        if (!$row = mysqli_fetch_assoc($res) ||
-                $row['_vers'] == 'unknown')
+        if (!($row = mysqli_fetch_assoc($res)) || $row['_vers'] == 'unknown')
             printf("[015] Results seem wrong, got %s, [%d] %s\n",
                 $row['_vers'],
                 mysqli_errno($link), mysqli_error($link));
@@ -135,8 +134,7 @@ END;')) {
         if (!$res = mysqli_query($link, 'SELECT @version as _vers'))
             printf("[021] Cannot fetch user variable, [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
-        if (!$row = mysqli_fetch_assoc($res) ||
-                $row['_vers'] == 'myversion')
+        if (!($row = mysqli_fetch_assoc($res)) || $row['_vers'] !== 'myversion')
             printf("[022] Results seem wrong, got %s, [%d] %s\n",
                 $row['_vers'],
                 mysqli_errno($link), mysqli_error($link));
diff --git a/ext/mysqli/tests/mysqli_query_unicode.phpt b/ext/mysqli/tests/mysqli_query_unicode.phpt
index c8c9e052de94..0e4a1095cf8d 100644
--- a/ext/mysqli/tests/mysqli_query_unicode.phpt
+++ b/ext/mysqli/tests/mysqli_query_unicode.phpt
@@ -40,7 +40,7 @@ mysqli_close($link);
         // let's try to play with stored procedures
         mysqli_query($link, 'DROP PROCEDURE IF EXISTS процедурка');
         if (mysqli_query($link, 'CREATE PROCEDURE процедурка(OUT версия VARCHAR(25)) BEGIN SELECT VERSION() INTO версия; END;')) {
-            $res = mysqli_query($link, 'CALL процедурка(@version)');
+            mysqli_query($link, 'CALL процедурка(@version)');
             $res = mysqli_query($link, 'SELECT @version AS п_версия');
 
             $tmp = mysqli_fetch_assoc($res);
diff --git a/ext/mysqli/tests/mysqli_real_connect_compression_error.phpt b/ext/mysqli/tests/mysqli_real_connect_compression_error.phpt
index 7a452d3a23cf..ad595366c317 100644
--- a/ext/mysqli/tests/mysqli_real_connect_compression_error.phpt
+++ b/ext/mysqli/tests/mysqli_real_connect_compression_error.phpt
@@ -24,7 +24,7 @@ $data_size = 16777174;
 // Insert with compression disabled:
 
 $mysqli = mysqli_init();
-$result = my_mysqli_real_connect($mysqli, $host, $user, $passwd, $db, $port, $socket);
+my_mysqli_real_connect($mysqli, $host, $user, $passwd, $db, $port, $socket);
 $mysqli->query("DROP TABLE IF EXISTS test");
 $mysqli->query("CREATE TABLE test (`blob` LONGBLOB NOT NULL) ENGINE=MyISAM");
 
@@ -37,7 +37,7 @@ $mysqli->close();
 // Insert with compression enabled:
 
 $mysqli = mysqli_init();
-$result = my_mysqli_real_connect($mysqli, $host, $user, $passwd, $db, $port, $socket, MYSQLI_CLIENT_COMPRESS);
+my_mysqli_real_connect($mysqli, $host, $user, $passwd, $db, $port, $socket, MYSQLI_CLIENT_COMPRESS);
 
 $data = str_repeat("x", $data_size);
 $mysqli->query("INSERT INTO $db.test(`blob`) VALUE ('$data')");
diff --git a/ext/mysqli/tests/mysqli_reap_async_query.phpt b/ext/mysqli/tests/mysqli_reap_async_query.phpt
index 19f907bd4a36..fae4f91a1d9c 100644
--- a/ext/mysqli/tests/mysqli_reap_async_query.phpt
+++ b/ext/mysqli/tests/mysqli_reap_async_query.phpt
@@ -18,10 +18,6 @@ require_once 'skipifconnectfailure.inc';
         return $link;
     }
 
-    if (!$link = get_connection())
-        printf("[001] [%d] %s\n", mysqli_connect_errno(), mysqli_connect_error());
-
-
     function poll_async($offset, $link, $links, $errors, $reject, $exp_ready, $use_oo_syntax) {
 
         if ($exp_ready !== ($tmp = mysqli_poll($links, $errors, $reject, 0, 50 * 1000)))
diff --git a/ext/mysqli/tests/mysqli_reap_async_query_error.phpt b/ext/mysqli/tests/mysqli_reap_async_query_error.phpt
index e7de2b6c9fe9..f7cbfbd363ed 100644
--- a/ext/mysqli/tests/mysqli_reap_async_query_error.phpt
+++ b/ext/mysqli/tests/mysqli_reap_async_query_error.phpt
@@ -19,7 +19,7 @@ mysqli::poll($reads, $errors, $rejects, 1);
 $link = $reads[0];
 
 try {
-    $rs = $link->reap_async_query();
+    $link->reap_async_query();
 } catch (mysqli_sql_exception $exception) {
     echo $exception->getMessage() . "\n";
 }
diff --git a/ext/mysqli/tests/mysqli_release_savepoint.phpt b/ext/mysqli/tests/mysqli_release_savepoint.phpt
index 8c896af7657a..f1d7fba992d3 100644
--- a/ext/mysqli/tests/mysqli_release_savepoint.phpt
+++ b/ext/mysqli/tests/mysqli_release_savepoint.phpt
@@ -36,7 +36,7 @@ if (!have_innodb($link))
 
     /* note that there is no savepoint my... */
     if (false !== ($tmp = mysqli_release_savepoint($link, 'my')))
-        printf("[010] Got %s - [%d] %s\n", var_dump($tmp, true), mysqli_errno($link), mysqli_error($link));
+        printf("[010] Got %s - [%d] %s\n", $tmp, mysqli_errno($link), mysqli_error($link));
 
     if (!mysqli_query($link, 'INSERT INTO test(id) VALUES (1)'))
         printf("[011] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
@@ -46,13 +46,13 @@ if (!have_innodb($link))
         printf("[012] Expecting boolean/true, got %s/%s\n", gettype($tmp), $tmp);
 
     if (true !== ($tmp = mysqli_savepoint($link, 'my')))
-        printf("[013] Got %s - [%d] %s\n", var_dump($tmp, true), mysqli_errno($link), mysqli_error($link));
+        printf("[013] Got %s - [%d] %s\n", $tmp, mysqli_errno($link), mysqli_error($link));
 
     $res = mysqli_query($link, "SELECT * FROM test");
     var_dump($res->fetch_assoc());
 
     if (true !== ($tmp = mysqli_release_savepoint($link, 'my')))
-        printf("[014] Got %s - [%d] %s\n", var_dump($tmp, true), mysqli_errno($link), mysqli_error($link));
+        printf("[014] Got %s - [%d] %s\n", $tmp, mysqli_errno($link), mysqli_error($link));
 
     print "done!";
 ?>
diff --git a/ext/mysqli/tests/mysqli_report.phpt b/ext/mysqli/tests/mysqli_report.phpt
index afde537aee4d..19b70a0f2b46 100644
--- a/ext/mysqli/tests/mysqli_report.phpt
+++ b/ext/mysqli/tests/mysqli_report.phpt
@@ -55,7 +55,7 @@ require_once 'skipifconnectfailure.inc';
     mysqli_stmt_prepare($stmt, "SELECT id FROM test WHERE id > ?");
     while(mysqli_more_results($link)) {
         mysqli_next_result($link);
-        $res = mysqli_store_result($link);
+        mysqli_store_result($link);
     }
     mysqli_next_result($link);
 
@@ -85,7 +85,7 @@ require_once 'skipifconnectfailure.inc';
     mysqli_stmt_prepare($stmt, "SELECT id FROM test WHERE id > ?");
     while(mysqli_more_results($link)) {
         mysqli_next_result($link);
-        $res = mysqli_store_result($link);
+        mysqli_store_result($link);
     }
     mysqli_next_result($link);
 
@@ -211,8 +211,6 @@ require_once 'skipifconnectfailure.inc';
 
     TODO:
     */
-    $log_slow_queries = false;
-    $log_queries_not_using_indexes = false;
     mysqli_report(MYSQLI_REPORT_OFF);
     mysqli_report(MYSQLI_REPORT_INDEX);
 
@@ -227,7 +225,7 @@ require_once 'skipifconnectfailure.inc';
         if (!$row = mysqli_fetch_assoc($res))
             printf("[019] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
-        $log_slow_query = ('ON' == $row['Value']);
+        $log_slow_queries = ('ON' == $row['Value']);
 
         if (mysqli_get_server_version($link) >= 50111) {
             // this might cause a warning - no index used
@@ -301,8 +299,6 @@ require_once 'skipifconnectfailure.inc';
             !mysqli_query($link, 'DELETE FROM test WHERE id > 50', MYSQLI_USE_RESULT))
         printf("[033] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
-    $tmp = mysqli_thread_id($link);
-
     mysqli_close($link);
     print "done!";
 ?>
diff --git a/ext/mysqli/tests/mysqli_result_invalid_mode.phpt b/ext/mysqli/tests/mysqli_result_invalid_mode.phpt
index f0799120742b..1b9c8601ba7c 100644
--- a/ext/mysqli/tests/mysqli_result_invalid_mode.phpt
+++ b/ext/mysqli/tests/mysqli_result_invalid_mode.phpt
@@ -15,7 +15,6 @@ require_once 'skipifconnectfailure.inc';
         exit(1);
     }
 
-    $valid = array(MYSQLI_STORE_RESULT, MYSQLI_USE_RESULT);
     $invalidModes = [-1, 152];
     foreach ($invalidModes as $mode) {
         try {
diff --git a/ext/mysqli/tests/mysqli_savepoint.phpt b/ext/mysqli/tests/mysqli_savepoint.phpt
index 810a0842498e..0de39d7d7154 100644
--- a/ext/mysqli/tests/mysqli_savepoint.phpt
+++ b/ext/mysqli/tests/mysqli_savepoint.phpt
@@ -36,7 +36,7 @@ if (!have_innodb($link))
 
     /* overrule autocommit */
     if (true !== ($tmp = mysqli_savepoint($link, 'my')))
-        printf("[010] Got %s - [%d] %s\n", var_dump($tmp, true), mysqli_errno($link), mysqli_error($link));
+        printf("[010] Got %s - [%d] %s\n", $tmp, mysqli_errno($link), mysqli_error($link));
 
     if (!mysqli_query($link, 'INSERT INTO test(id) VALUES (1)'))
         printf("[011] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
diff --git a/ext/mysqli/tests/mysqli_select_db.phpt b/ext/mysqli/tests/mysqli_select_db.phpt
index 33c55c12409c..a0c38ebbb676 100644
--- a/ext/mysqli/tests/mysqli_select_db.phpt
+++ b/ext/mysqli/tests/mysqli_select_db.phpt
@@ -45,7 +45,7 @@ require_once 'skipifconnectfailure.inc';
     }
 
     if (!$link->select_db($db))
-        printf("[012] Failed to set '%s' as current DB; [%d] %s\n", $link->errno, $link->error);
+        printf("[012] Failed to set '%s' as current DB; [%d] %s\n", $db, $link->errno, $link->error);
 
     if (!$res = mysqli_query($link, "SELECT DATABASE() AS dbname"))
         printf("[013] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
@@ -81,9 +81,9 @@ require_once 'skipifconnectfailure.inc';
 
 
     if (!$res = $link->query("SELECT id FROM test WHERE id = 1"))
-        printf("[018] [%d] %s\n");
+        printf("[018] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
-    $row = $res->fetch_assoc();
+    $res->fetch_assoc();
     $res->free();
 
     mysqli_close($link);
diff --git a/ext/mysqli/tests/mysqli_set_charset.phpt b/ext/mysqli/tests/mysqli_set_charset.phpt
index 4dff9668b531..4a873f65eb43 100644
--- a/ext/mysqli/tests/mysqli_set_charset.phpt
+++ b/ext/mysqli/tests/mysqli_set_charset.phpt
@@ -17,7 +17,6 @@ if ((($res = mysqli_query($link, 'SHOW CHARACTER SET LIKE "latin1"', MYSQLI_STOR
     mysqli_close($link);
 } else {
     die(sprintf("skip Requires character set latin1 or latin2\n"));
-    mysqli_close($link);
 }
 ?>
 --FILE--
diff --git a/ext/mysqli/tests/mysqli_stat.phpt b/ext/mysqli/tests/mysqli_stat.phpt
index d58aa0863d87..4417cb265b80 100644
--- a/ext/mysqli/tests/mysqli_stat.phpt
+++ b/ext/mysqli/tests/mysqli_stat.phpt
@@ -17,7 +17,7 @@ require_once 'skipifconnectfailure.inc';
 
     if ((!is_string($tmp = mysqli_stat($link))) || ('' === $tmp))
         printf("[004] Expecting non empty string, got %s/'%s', [%d] %s\n",
-            gettype($tmp), $tmp, mysqli_errno($link), mysql_error($link));
+            gettype($tmp), $tmp, mysqli_errno($link), mysqli_error($link));
 
     mysqli_close($link);
 
diff --git a/ext/mysqli/tests/mysqli_stmt_attr_get.phpt b/ext/mysqli/tests/mysqli_stmt_attr_get.phpt
index 942711faa141..f7de1e04c604 100644
--- a/ext/mysqli/tests/mysqli_stmt_attr_get.phpt
+++ b/ext/mysqli/tests/mysqli_stmt_attr_get.phpt
@@ -11,9 +11,9 @@ require_once 'skipifconnectfailure.inc';
     require 'table.inc';
 
     $valid_attr = array(
-        "max_length" => MYSQLI_STMT_ATTR_UPDATE_MAX_LENGTH,
-        "cursor_type" => MYSQLI_STMT_ATTR_CURSOR_TYPE,
-        "prefetch_rows" => MYSQLI_STMT_ATTR_PREFETCH_ROWS,
+        MYSQLI_STMT_ATTR_UPDATE_MAX_LENGTH,
+        MYSQLI_STMT_ATTR_CURSOR_TYPE,
+        MYSQLI_STMT_ATTR_PREFETCH_ROWS,
     );
 
     $stmt = mysqli_stmt_init($link);
@@ -25,17 +25,17 @@ require_once 'skipifconnectfailure.inc';
         echo $e->getMessage() . \PHP_EOL;
     }
 
-    foreach ($valid_attr as $k => $attr) {
-        /* This can't happen anymore as it only returns int */
-        if (false === ($tmp = mysqli_stmt_attr_get($stmt, $attr))) {
-            printf("[006] Expecting any type, but not boolean/false, got %s/%s for attribute %s/%s\n",
-                gettype($tmp), $tmp, $k, $attr);
+    foreach ($valid_attr as $attr) {
+        try {
+            mysqli_stmt_attr_get($stmt, $attr);
+        } catch (Throwable $exception) {
+            echo $exception->getMessage() . "\n";
         }
     }
 
     $stmt->close();
 
-    foreach ($valid_attr as $k => $attr) {
+    foreach ($valid_attr as $attr) {
         try {
             mysqli_stmt_attr_get($stmt, $attr);
         } catch (Throwable $exception) {
diff --git a/ext/mysqli/tests/mysqli_stmt_attr_set.phpt b/ext/mysqli/tests/mysqli_stmt_attr_set.phpt
index 304046919a1a..070d4a389bca 100644
--- a/ext/mysqli/tests/mysqli_stmt_attr_set.phpt
+++ b/ext/mysqli/tests/mysqli_stmt_attr_set.phpt
@@ -10,15 +10,6 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require 'table.inc';
 
-    $valid_attr = array(MYSQLI_STMT_ATTR_UPDATE_MAX_LENGTH);
-    $valid_attr[] = MYSQLI_STMT_ATTR_CURSOR_TYPE;
-    $valid_attr[] =	MYSQLI_CURSOR_TYPE_NO_CURSOR;
-    $valid_attr[] =	MYSQLI_CURSOR_TYPE_READ_ONLY;
-    $valid_attr[] =	MYSQLI_CURSOR_TYPE_FOR_UPDATE;
-    $valid_attr[] =	MYSQLI_CURSOR_TYPE_SCROLLABLE;
-    $valid_attr[] = MYSQLI_STMT_ATTR_PREFETCH_ROWS;
-
-
     $stmt = mysqli_stmt_init($link);
     try {
         mysqli_stmt_attr_set($stmt, 0, 0);
@@ -51,9 +42,7 @@ require_once 'skipifconnectfailure.inc';
     $stmt->store_result();
     $res = $stmt->result_metadata();
     $fields = $res->fetch_fields();
-    $max_lengths = array();
-    foreach ($fields as $k => $meta) {
-        $max_lengths[$meta->name] = $meta->max_length;
+    foreach ($fields as $meta) {
         if ($meta->max_length !== 0)
             printf("[007] max_length should be not set (= 0), got %s for field %s\n", $meta->max_length, $meta->name);
     }
@@ -71,9 +60,7 @@ require_once 'skipifconnectfailure.inc';
     $stmt->store_result();
     $res = $stmt->result_metadata();
     $fields = $res->fetch_fields();
-    $max_lengths = array();
-    foreach ($fields as $k => $meta) {
-        $max_lengths[$meta->name] = $meta->max_length;
+    foreach ($fields as $meta) {
         if ($meta->max_length !== 0)
             printf("[008] max_length should be not set (= 0), got %s for field %s\n", $meta->max_length, $meta->name);
     }
@@ -91,9 +78,7 @@ require_once 'skipifconnectfailure.inc';
     $stmt->store_result();
     $res = $stmt->result_metadata();
     $fields = $res->fetch_fields();
-    $max_lengths = array();
-    foreach ($fields as $k => $meta) {
-        $max_lengths[$meta->name] = $meta->max_length;
+    foreach ($fields as $meta) {
         if ($meta->max_length !== 0)
             printf("[009] max_length should not be set (= 0), got %s for field %s\n", $meta->max_length, $meta->name);
     }
diff --git a/ext/mysqli/tests/mysqli_stmt_bind_param.phpt b/ext/mysqli/tests/mysqli_stmt_bind_param.phpt
index 180de7cc43f2..c4b0c21f2586 100644
--- a/ext/mysqli/tests/mysqli_stmt_bind_param.phpt
+++ b/ext/mysqli/tests/mysqli_stmt_bind_param.phpt
@@ -382,14 +382,14 @@ require_once 'skipifconnectfailure.inc';
     if (!mysqli_stmt_prepare($stmt, "INSERT INTO test(id, label) VALUES (?, ?)"))
         printf("[2010] [%d] %s\n", mysqli_stmt_errno($stmt), mysqli_stmt_error($stmt));
 
-        foreach ($value_list as $k => $values) {
+        foreach ($value_list as $values) {
         if (!mysqli_stmt_bind_param($stmt, 'is', $values['id'], $values['label'])) {
             printf("[2011] bind_param() failed for id = %d, [%d] %s\n",
                 $values['id'], mysqli_stmt_errno($stmt), mysqli_stmt_error($stmt));
             continue;
         }
         if (!$stmt->execute())
-            printf("[2012] [%d] execute() failed for id = %d, [%d] %s\n",
+            printf("[2012] execute() failed for id = %d, [%d] %s\n",
                 $values['id'], mysqli_stmt_errno($stmt), mysqli_stmt_error($stmt));
 
         if (!$res = mysqli_query($link, sprintf("SELECT label FROM test WHERE id = %d", $values['id'])))
diff --git a/ext/mysqli/tests/mysqli_stmt_bind_param_call_user_func.phpt b/ext/mysqli/tests/mysqli_stmt_bind_param_call_user_func.phpt
index 40296ad63d2d..844d2974af00 100644
--- a/ext/mysqli/tests/mysqli_stmt_bind_param_call_user_func.phpt
+++ b/ext/mysqli/tests/mysqli_stmt_bind_param_call_user_func.phpt
@@ -309,7 +309,6 @@ require_once 'skipifconnectfailure.inc';
     if (!mysqli_stmt_prepare($stmt, 'SELECT id, label FROM test WHERE id = ?'))
         printf("[050] [%d] %s\n", mysqli_stmt_errno($stmt), mysqli_stmt_error($stmt));
 
-    $types = 'i';
     $id = 1;
     $params = array(
         0 => $stmt,
diff --git a/ext/mysqli/tests/mysqli_stmt_bind_result.phpt b/ext/mysqli/tests/mysqli_stmt_bind_result.phpt
index 5a210f3d2e35..d4d61380ff2e 100644
--- a/ext/mysqli/tests/mysqli_stmt_bind_result.phpt
+++ b/ext/mysqli/tests/mysqli_stmt_bind_result.phpt
@@ -275,7 +275,7 @@ require_once 'skipifconnectfailure.inc';
     try {
         mysqli_stmt_bind_result($stmt, $id);
     } catch (\ArgumentCountError $e) {
-        $e->getMessage() . \PHP_EOL;
+        echo $e->getMessage() . \PHP_EOL;
     }
 
     mysqli_stmt_close($stmt);
@@ -293,4 +293,5 @@ Number of bind variables doesn't match number of fields in prepared statement
 Number of bind variables doesn't match number of fields in prepared statement
 int(1)
 %s(1) "a"
+Number of bind variables doesn't match number of fields in prepared statement
 done!
diff --git a/ext/mysqli/tests/mysqli_stmt_close.phpt b/ext/mysqli/tests/mysqli_stmt_close.phpt
index d031077009a0..89d278060161 100644
--- a/ext/mysqli/tests/mysqli_stmt_close.phpt
+++ b/ext/mysqli/tests/mysqli_stmt_close.phpt
@@ -23,8 +23,7 @@ require_once 'skipifconnectfailure.inc';
     if (!mysqli_stmt_prepare($stmt, "SELECT id, label FROM test"))
         printf("[005] [%d] %s\n", mysqli_stmt_errno($stmt), mysqli_stmt_error($stmt));
 
-    if (true !== ($tmp = mysqli_stmt_close($stmt)))
-        printf("[006] Expecting boolean/true, got %s/%s\n", gettype($tmp), $tmp);
+    mysqli_stmt_close($stmt);
 
     try {
         mysqli_stmt_close($stmt);
@@ -48,8 +47,7 @@ require_once 'skipifconnectfailure.inc';
 
     $link->query('KILL '.mysqli_thread_id($link));
 
-    if (true !== ($tmp = mysqli_stmt_close($stmt)))
-        printf("[012] Expecting boolean/true, got %s/%s\n", gettype($tmp), $tmp);
+    mysqli_stmt_close($stmt);
 
     mysqli_close($link);
 
@@ -69,8 +67,7 @@ require_once 'skipifconnectfailure.inc';
 
     $link->query('KILL '.mysqli_thread_id($link));
 
-    if (true !== ($tmp = mysqli_stmt_close($stmt)))
-        printf("[017] Expecting boolean/true, got %s/%s\n", gettype($tmp), $tmp);
+    mysqli_stmt_close($stmt);
 
     print "done!";
 ?>
diff --git a/ext/mysqli/tests/mysqli_stmt_data_seek.phpt b/ext/mysqli/tests/mysqli_stmt_data_seek.phpt
index 21f8286cac08..a36daebc7951 100644
--- a/ext/mysqli/tests/mysqli_stmt_data_seek.phpt
+++ b/ext/mysqli/tests/mysqli_stmt_data_seek.phpt
@@ -33,24 +33,21 @@ require_once 'skipifconnectfailure.inc';
     if (!mysqli_stmt_store_result($stmt))
         printf("[008] [%d] %s\n", mysqli_stmt_errno($stmt), mysqli_stmt_error($stmt));
 
-    if (!is_null($tmp = mysqli_stmt_data_seek($stmt, 2)))
-        printf("[009] Expecting NULL, got %s/%s\n", gettype($tmp), $tmp);
+    mysqli_stmt_data_seek($stmt, 2);
 
     if (!mysqli_stmt_fetch($stmt))
         printf("[010] [%d] %s\n", mysqli_stmt_errno($stmt), mysqli_stmt_error($stmt));
 
     var_dump($id);
 
-    if (!is_null($tmp = mysqli_stmt_data_seek($stmt, 0)))
-        printf("[011] Expecting NULL, got %s/%s\n", gettype($tmp), $tmp);
+    mysqli_stmt_data_seek($stmt, 0);
 
     if (!mysqli_stmt_fetch($stmt))
         printf("[012] [%d] %s\n", mysqli_stmt_errno($stmt), mysqli_stmt_error($stmt));
 
     var_dump($id);
 
-    if (!is_null($tmp = mysqli_stmt_data_seek($stmt, mysqli_stmt_num_rows($stmt) + 100)))
-        printf("[013] Expecting NULL, got %s/%s\n", gettype($tmp), $tmp);
+    mysqli_stmt_data_seek($stmt, mysqli_stmt_num_rows($stmt) + 100);
 
     if (mysqli_stmt_fetch($stmt))
         printf("[014] [%d] %s\n", mysqli_stmt_errno($stmt), mysqli_stmt_error($stmt));
diff --git a/ext/mysqli/tests/mysqli_stmt_execute_stored_proc_out.phpt b/ext/mysqli/tests/mysqli_stmt_execute_stored_proc_out.phpt
index bdfc9c348ae2..03c070dad482 100644
--- a/ext/mysqli/tests/mysqli_stmt_execute_stored_proc_out.phpt
+++ b/ext/mysqli/tests/mysqli_stmt_execute_stored_proc_out.phpt
@@ -52,7 +52,7 @@ if (mysqli_get_server_version($link) < 50503) {
         if (!mysqli_stmt_close($stmt))
             printf("[012] Cannot close statement, [%d] %s\n", mysqli_stmt_errno($stmt), mysqli_stmt_error($stmt));
 
-        if (!$res = $link->query("SELECT 1"))
+        if (false === $link->query("SELECT 1"))
             printf("[013] [%d] %s\n", $link->errno, $link->error);
 
     } else {
diff --git a/ext/mysqli/tests/mysqli_stmt_fetch_fields_win32_unicode.phpt b/ext/mysqli/tests/mysqli_stmt_fetch_fields_win32_unicode.phpt
index 48e2e6f8dec6..90348833e57f 100644
--- a/ext/mysqli/tests/mysqli_stmt_fetch_fields_win32_unicode.phpt
+++ b/ext/mysqli/tests/mysqli_stmt_fetch_fields_win32_unicode.phpt
@@ -17,7 +17,7 @@ require_once 'skipifconnectfailure.inc';
         !mysqli_stmt_execute($stmt) ||
         !($result = mysqli_stmt_result_metadata($stmt)) ||
         !mysqli_stmt_bind_result($stmt, $id, $bind_res) ||
-        !($fields = mysqli_fetch_fields($result))) {
+        [] === mysqli_fetch_fields($result)) {
         printf("FAIL 1\n");
     }
     while (mysqli_stmt_fetch($stmt)) {
@@ -34,7 +34,7 @@ require_once 'skipifconnectfailure.inc';
         printf("FAIL 2\n");
     }
     print "OK: 1\n";
-    if (!($fields = mysqli_fetch_fields($result)))
+    if ([] === mysqli_fetch_fields($result))
         printf("Aua 3\n");
     print "OK: 2\n";
     while (mysqli_stmt_fetch($stmt)) {
diff --git a/ext/mysqli/tests/mysqli_stmt_free_result.phpt b/ext/mysqli/tests/mysqli_stmt_free_result.phpt
index e049e8410477..d512a23ee037 100644
--- a/ext/mysqli/tests/mysqli_stmt_free_result.phpt
+++ b/ext/mysqli/tests/mysqli_stmt_free_result.phpt
@@ -28,14 +28,12 @@ require_once 'skipifconnectfailure.inc';
     if (!mysqli_stmt_prepare($stmt, "SELECT id, label FROM test ORDER BY id"))
         printf("[005] [%d] %s\n", mysqli_stmt_errno($stmt), mysqli_stmt_error($stmt));
 
-    if (NULL !== ($tmp = mysqli_stmt_free_result($stmt)))
-        printf("[006] Expecting NULL, got %s/%s\n", gettype($tmp), $tmp);
+    mysqli_stmt_free_result($stmt);
 
     if (!mysqli_stmt_execute($stmt))
         printf("[007] [%d] %s\n", mysqli_stmt_errno($stmt), mysqli_stmt_error($stmt));
 
-    if (NULL !== ($tmp = mysqli_stmt_free_result($stmt)))
-        printf("[008] Expecting NULL, got %s/%s\n", gettype($tmp), $tmp);
+    mysqli_stmt_free_result($stmt);
 
     if (false !== ($tmp = mysqli_stmt_store_result($stmt)))
         printf("[009] Expecting boolean/false, got %s/%s\n", gettype($tmp), $tmp);
@@ -54,8 +52,7 @@ require_once 'skipifconnectfailure.inc';
     if (true !== ($tmp = mysqli_stmt_store_result($stmt)))
         printf("[013] Expecting boolean/true, got %s/%s\n", gettype($tmp), $tmp);
 
-    if (NULL !== ($tmp = mysqli_stmt_free_result($stmt)))
-        printf("[014] Expecting NULL, got %s/%s\n", gettype($tmp), $tmp);
+    mysqli_stmt_free_result($stmt);
 
     mysqli_stmt_close($stmt);
 
diff --git a/ext/mysqli/tests/mysqli_stmt_get_result2.phpt b/ext/mysqli/tests/mysqli_stmt_get_result2.phpt
index a5352af94db8..5178d2b60975 100644
--- a/ext/mysqli/tests/mysqli_stmt_get_result2.phpt
+++ b/ext/mysqli/tests/mysqli_stmt_get_result2.phpt
@@ -102,7 +102,7 @@ require_once 'skipifconnectfailure.inc';
     if (!mysqli_stmt_bind_result($stmt, $id, $label))
         printf("[020] [%d] %s\n", mysqli_stmt_errno($stmt), mysqli_stmt_error($stmt));
 
-    $row = mysqli_fetch_assoc($res);
+    mysqli_fetch_assoc($res);
     if (NULL !== $id || NULL !== $label)
         printf("[021] Bound variables should not have been set\n");
     mysqli_free_result($res);
diff --git a/ext/mysqli/tests/mysqli_stmt_multires.phpt b/ext/mysqli/tests/mysqli_stmt_multires.phpt
index 0352a464e86f..94538cbc5d8d 100644
--- a/ext/mysqli/tests/mysqli_stmt_multires.phpt
+++ b/ext/mysqli/tests/mysqli_stmt_multires.phpt
@@ -10,7 +10,6 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require 'table.inc';
 
-    $stmt = mysqli_stmt_init($link);
     if (!$link->query('DROP PROCEDURE IF EXISTS p123')) {
         printf("[001] [%d] %s\n", $link->error, $link->errno);
     }
diff --git a/ext/mysqli/tests/mysqli_stmt_result_metadata.phpt b/ext/mysqli/tests/mysqli_stmt_result_metadata.phpt
index a29da62893fb..8d73967777a6 100644
--- a/ext/mysqli/tests/mysqli_stmt_result_metadata.phpt
+++ b/ext/mysqli/tests/mysqli_stmt_result_metadata.phpt
@@ -23,7 +23,7 @@ require_once 'skipifconnectfailure.inc';
         printf("[005] [%d] %s\n", mysqli_stmt_errno($stmt), mysqli_stmt_error($stmt));
 
     if (!is_object(($res = mysqli_stmt_result_metadata($stmt))))
-        printf("[006] Expecting object, got %s/%s\n", gettype($tmp), $tmp);
+        printf("[006] Expecting object, got %s/%s\n", gettype($res), $res);
 
     if (2 !== ($tmp = mysqli_num_fields($res)))
         printf("[007] Expecting int/2, got %s/%s, [%d] %s\n",
@@ -45,9 +45,7 @@ require_once 'skipifconnectfailure.inc';
 
     var_dump($field0_fetch);
 
-    if (!is_array($tmp = mysqli_fetch_fields($res)))
-        printf("[011] Expecting array, got %s/%s, [%d] %s\n",
-            gettype($tmp), $tmp, mysqli_errno($link), mysqli_error($link));
+    $tmp = mysqli_fetch_fields($res);
 
     if (empty($tmp[0]) || empty($tmp[1]) || $tmp[0] != $field0_direct) {
         printf("[012] mysqli_fetch_fields() return value is suspicious\n");
diff --git a/ext/mysqli/tests/mysqli_stmt_send_long_data.phpt b/ext/mysqli/tests/mysqli_stmt_send_long_data.phpt
index cc4a92727091..dbf8dddb88e4 100644
--- a/ext/mysqli/tests/mysqli_stmt_send_long_data.phpt
+++ b/ext/mysqli/tests/mysqli_stmt_send_long_data.phpt
@@ -64,7 +64,7 @@ require_once 'skipifconnectfailure.inc';
     assert(strlen($blob) <= $max_allowed_packet);
 
     try {
-        $tmp = mysqli_stmt_send_long_data($stmt, -1, $blob);
+        mysqli_stmt_send_long_data($stmt, -1, $blob);
     } catch (\ValueError $e) {
         echo $e->getMessage() . \PHP_EOL;
     }
diff --git a/ext/mysqli/tests/mysqli_stmt_send_long_data_packet_size_mysqlnd.phpt b/ext/mysqli/tests/mysqli_stmt_send_long_data_packet_size_mysqlnd.phpt
index 5c7ffd9c6da4..79cf0aa79450 100644
--- a/ext/mysqli/tests/mysqli_stmt_send_long_data_packet_size_mysqlnd.phpt
+++ b/ext/mysqli/tests/mysqli_stmt_send_long_data_packet_size_mysqlnd.phpt
@@ -40,8 +40,6 @@ require_once 'skipifconnectfailure.inc';
 
     // let's ignore upper limits for LONGBLOB (2^32) ...
     // maximum packet size up to which we test is 10M
-    $tmp = '';
-    $blob = '';
     $tmp = str_repeat('a', 1024);
 
     $limit = min(floor($max_allowed_packet / 1024 / 2), 10240);
diff --git a/ext/mysqli/tests/mysqli_store_result.phpt b/ext/mysqli/tests/mysqli_store_result.phpt
index f3d743916b7c..2a35320a63ae 100644
--- a/ext/mysqli/tests/mysqli_store_result.phpt
+++ b/ext/mysqli/tests/mysqli_store_result.phpt
@@ -10,7 +10,7 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require 'table.inc';
 
-    if (!$res = mysqli_real_query($link, "SELECT id, label FROM test ORDER BY id"))
+    if (false === mysqli_real_query($link, "SELECT id, label FROM test ORDER BY id"))
         printf("[003] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
     if (!is_object($res = mysqli_store_result($link)))
diff --git a/ext/mysqli/tests/mysqli_store_result_buffered_c.phpt b/ext/mysqli/tests/mysqli_store_result_buffered_c.phpt
index 18ca399af36c..65f9f5d13230 100644
--- a/ext/mysqli/tests/mysqli_store_result_buffered_c.phpt
+++ b/ext/mysqli/tests/mysqli_store_result_buffered_c.phpt
@@ -10,7 +10,7 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require 'table.inc';
 
-    if (!$res = mysqli_real_query($link, "SELECT id, label FROM test ORDER BY id"))
+    if (false === mysqli_real_query($link, "SELECT id, label FROM test ORDER BY id"))
         printf("[003] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
     if (!is_object($res = mysqli_store_result($link)))
diff --git a/ext/mysqli/tests/mysqli_use_result.phpt b/ext/mysqli/tests/mysqli_use_result.phpt
index d5a34a9d08d6..293f11854b1b 100644
--- a/ext/mysqli/tests/mysqli_use_result.phpt
+++ b/ext/mysqli/tests/mysqli_use_result.phpt
@@ -10,7 +10,7 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require 'table.inc';
 
-    if (!$res = mysqli_real_query($link, "SELECT id, label FROM test ORDER BY id"))
+    if (false === mysqli_real_query($link, "SELECT id, label FROM test ORDER BY id"))
         printf("[003] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
     if (!is_object($res = mysqli_use_result($link)))
diff --git a/ext/mysqli/tests/mysqli_warning_count.phpt b/ext/mysqli/tests/mysqli_warning_count.phpt
index c844d6f4d81f..7080a035c3a3 100644
--- a/ext/mysqli/tests/mysqli_warning_count.phpt
+++ b/ext/mysqli/tests/mysqli_warning_count.phpt
@@ -10,7 +10,7 @@ require_once 'skipifconnectfailure.inc';
 <?php
     require 'table.inc';
 
-    if (!$res = mysqli_query($link, "SELECT id, label FROM test"))
+    if (false === mysqli_query($link, "SELECT id, label FROM test"))
         printf("[004] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
     if (0 !== ($tmp = mysqli_warning_count($link)))
diff --git a/ext/mysqli/tests/mysqli_warning_unclonable.phpt b/ext/mysqli/tests/mysqli_warning_unclonable.phpt
index c51747b51449..7e404563f5df 100644
--- a/ext/mysqli/tests/mysqli_warning_unclonable.phpt
+++ b/ext/mysqli/tests/mysqli_warning_unclonable.phpt
@@ -26,7 +26,7 @@ if (!$TEST_EXPERIMENTAL)
         printf("[004] [%d] %s\n", mysqli_errno($link), mysqli_error($link));
 
     if (!is_object($warning = mysqli_get_warnings($link)) || 'mysqli_warning' != get_class($warning)) {
-        printf("[005] Expecting object/mysqli_warning, got %s/%s\n", gettype($tmp), (is_object($tmp) ? var_dump($tmp, true) : $tmp));
+        printf("[006] Expecting object/mysqli_warning, got %s/%s\n", gettype($warning), (is_object($warning) ? var_export($warning, true) : $warning));
     }
 
     $warning_clone = clone $warning;
diff --git a/ext/mysqli/tests/test_setup/test_helpers.inc b/ext/mysqli/tests/test_setup/test_helpers.inc
index 42d3e7ad515b..7c7503400686 100644
--- a/ext/mysqli/tests/test_setup/test_helpers.inc
+++ b/ext/mysqli/tests/test_setup/test_helpers.inc
@@ -109,7 +109,7 @@ function default_mysqli_connect(): \mysqli{
 }
 function mysqli_check_skip_test(): void {
     try {
-        $link = default_mysqli_connect();
+        default_mysqli_connect();
     } catch (\mysqli_sql_exception) {
         die(sprintf("skip Can't connect to MySQL Server - [%d] %s", mysqli_connect_errno(), mysqli_connect_error()));
     }