diff --git a/src/Curl/Curl.php b/src/Curl/Curl.php
index 334dfd7..3fe29ec 100644
--- a/src/Curl/Curl.php
+++ b/src/Curl/Curl.php
@@ -1884,7 +1884,7 @@ class Curl
      */
     private function parseHeaders($raw_headers)
     {
-        $raw_headers = preg_split('/\r\n/', $raw_headers, null, PREG_SPLIT_NO_EMPTY);
+        $raw_headers = preg_split('/\r\n/', (string) $raw_headers, -1, PREG_SPLIT_NO_EMPTY);
         $http_headers = new CaseInsensitiveArray();
 
         $raw_headers_count = count($raw_headers);
diff --git a/src/Curl/MultiCurl.php b/src/Curl/MultiCurl.php
index 13b9f8c..ee0e42b 100755
--- a/src/Curl/MultiCurl.php
+++ b/src/Curl/MultiCurl.php
@@ -1270,7 +1270,7 @@ class MultiCurl
         $sleep_seconds = $sleep_until - microtime(true);
 
         // Avoid using time_sleep_until() as it appears to be less precise and not sleep long enough.
-        usleep($sleep_seconds * 1000000);
+        usleep((int) $sleep_seconds * 1000000);
 
         // Ensure that enough time has passed as usleep() may not have waited long enough.
         $this->currentStartTime = microtime(true);
diff --git a/src/Curl/Url.php b/src/Curl/Url.php
index d811fc9..227d21b 100644
--- a/src/Curl/Url.php
+++ b/src/Curl/Url.php
@@ -194,7 +194,7 @@ class Url
         // $7 = <undefined> (query)
         // $8 = #Related (ignore)
         // $9 = Related (fragment)
-        preg_match('/^(([^:\/?#]+):)?(\/\/([^\/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?/', $url, $output_array);
+        preg_match('/^(([^:\/?#]+):)?(\/\/([^\/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?/', (string) $url, $output_array);
 
         $parts = [];
         if (isset($output_array['1']) && $output_array['1'] !== '') {
diff --git a/tests/PHPCurlClass/Helper.php b/tests/PHPCurlClass/Helper.php
index 79ded31..ac6eeaf 100644
--- a/tests/PHPCurlClass/Helper.php
+++ b/tests/PHPCurlClass/Helper.php
@@ -103,7 +103,7 @@ function get_tmp_file_path()
     // Return temporary file path without creating file.
     $tmp_file_path =
         rtrim(sys_get_temp_dir(), DIRECTORY_SEPARATOR) .
-        DIRECTORY_SEPARATOR . 'php-curl-class.' . uniqid(rand(), true);
+        DIRECTORY_SEPARATOR . 'php-curl-class.' . uniqid((string) rand(), true);
     return $tmp_file_path;
 }
 
diff --git a/tests/PHPCurlClass/PHPMultiCurlClassTest.php b/tests/PHPCurlClass/PHPMultiCurlClassTest.php
index 92bf42c..a43d4d2 100644
--- a/tests/PHPCurlClass/PHPMultiCurlClassTest.php
+++ b/tests/PHPCurlClass/PHPMultiCurlClassTest.php
@@ -2946,7 +2946,7 @@ class MultiCurlTest extends \PHPUnit\Framework\TestCase
         $urls = [];
         $copy_of_urls = [];
         for ($i = 0; $i < 10; $i++) {
-            $url = Test::TEST_URL . '?' . md5(mt_rand());
+            $url = Test::TEST_URL . '?' . md5((string) mt_rand());
             $urls[] = $url;
             $copy_of_urls[] = $url;
         }
diff --git a/tests/PHPCurlClass/server.php b/tests/PHPCurlClass/server.php
index 2f75d20..62a6ad9 100644
--- a/tests/PHPCurlClass/server.php
+++ b/tests/PHPCurlClass/server.php
@@ -264,7 +264,7 @@ if ($test === 'http_basic_auth') {
     exit;
 } elseif ($test === 'download_file_size') {
     $bytes = isset($_GET['bytes']) ? $_GET['bytes'] : 1234;
-    $str = str_repeat('.', $bytes);
+    $str = str_repeat('.', (int) $bytes);
     header('Content-Type: application/octet-stream');
     header('Content-Length: ' . strlen($str));
     header('ETag: ' . md5($str));
@@ -292,7 +292,7 @@ if ($test === 'http_basic_auth') {
         $dots_to_print = floor($elapsed) - $dots_printed;
 
         if ($dots_to_print) {
-            echo str_repeat('.', $dots_to_print);
+            echo str_repeat('.', (int) $dots_to_print);
             $dots_printed += $dots_to_print;
         }