diff --git a/ext/standard/string.c b/ext/standard/string.c
index c2f29baec7732..89d7b9274be88 100644
--- a/ext/standard/string.c
+++ b/ext/standard/string.c
@@ -5687,18 +5687,18 @@ PHP_FUNCTION(str_pad)
 	}
 
 	if (pad_str_len == 0) {
-		php_error_docref(NULL, E_WARNING, "Padding string cannot be empty");
+		zend_throw_error(NULL, "Padding string cannot be empty");
 		return;
 	}
 
 	if (pad_type_val < STR_PAD_LEFT || pad_type_val > STR_PAD_BOTH) {
-		php_error_docref(NULL, E_WARNING, "Padding type has to be STR_PAD_LEFT, STR_PAD_RIGHT, or STR_PAD_BOTH");
+		zend_throw_error(NULL, "Padding type has to be STR_PAD_LEFT, STR_PAD_RIGHT, or STR_PAD_BOTH");
 		return;
 	}
 
 	num_pad_chars = pad_length - ZSTR_LEN(input);
 	if (num_pad_chars >= INT_MAX) {
-		php_error_docref(NULL, E_WARNING, "Padding length is too long");
+		zend_throw_error(NULL, "Padding length is too long");
 		return;
 	}
 
diff --git a/ext/standard/tests/strings/str_pad.phpt b/ext/standard/tests/strings/str_pad.phpt
index be4c9ed942869..a4f60bfa6ae27 100644
Binary files a/ext/standard/tests/strings/str_pad.phpt and b/ext/standard/tests/strings/str_pad.phpt differ
diff --git a/ext/standard/tests/strings/str_pad_variation1.phpt b/ext/standard/tests/strings/str_pad_variation1.phpt
new file mode 100644
index 0000000000000..1ebf1b2825bd3
--- /dev/null
+++ b/ext/standard/tests/strings/str_pad_variation1.phpt
@@ -0,0 +1,70 @@
+--TEST--
+str_pad() function: usage variations - Non printable chars
+--INI--
+precision=14
+--FILE--
+<?php
+// Split from str_pad for NUL Bytes
+// 7-bit ASCII
+$string = chr(0).chr(255).chr(128).chr(234).chr(143);
+
+/* different pad_lengths */
+$pad_lengths = [
+    -PHP_INT_MAX,  // huge negative value
+	-1,  // negative value
+    0,  // pad_length < sizeof(input_string)
+    9,  // pad_length <= sizeof(input_string)
+    10,  // pad_length > sizeof(input_string)
+    16,  // pad_length > sizeof(input_string)
+];
+
+$pad_string = "=";
+
+/*loop through to use each variant of $pad_length on
+  each element of $input_strings array */
+foreach ($pad_lengths as $pad_length ) {
+    // default pad_string & pad_type
+    var_dump( bin2hex( str_pad($string, $pad_length) ) );
+    // default pad_type
+    var_dump( bin2hex( str_pad($string, $pad_length, $pad_string) ) );
+    var_dump( bin2hex( str_pad($string, $pad_length, $pad_string, STR_PAD_LEFT) ) );
+    var_dump( bin2hex( str_pad($string, $pad_length, $pad_string, STR_PAD_RIGHT) ) );
+    var_dump( bin2hex( str_pad($string, $pad_length, $pad_string, STR_PAD_BOTH) ) );
+}
+
+?>
+
+DONE
+--EXPECT--
+string(10) "00ff80ea8f"
+string(10) "00ff80ea8f"
+string(10) "00ff80ea8f"
+string(10) "00ff80ea8f"
+string(10) "00ff80ea8f"
+string(10) "00ff80ea8f"
+string(10) "00ff80ea8f"
+string(10) "00ff80ea8f"
+string(10) "00ff80ea8f"
+string(10) "00ff80ea8f"
+string(10) "00ff80ea8f"
+string(10) "00ff80ea8f"
+string(10) "00ff80ea8f"
+string(10) "00ff80ea8f"
+string(10) "00ff80ea8f"
+string(18) "00ff80ea8f20202020"
+string(18) "00ff80ea8f3d3d3d3d"
+string(18) "3d3d3d3d00ff80ea8f"
+string(18) "00ff80ea8f3d3d3d3d"
+string(18) "3d3d00ff80ea8f3d3d"
+string(20) "00ff80ea8f2020202020"
+string(20) "00ff80ea8f3d3d3d3d3d"
+string(20) "3d3d3d3d3d00ff80ea8f"
+string(20) "00ff80ea8f3d3d3d3d3d"
+string(20) "3d3d00ff80ea8f3d3d3d"
+string(32) "00ff80ea8f2020202020202020202020"
+string(32) "00ff80ea8f3d3d3d3d3d3d3d3d3d3d3d"
+string(32) "3d3d3d3d3d3d3d3d3d3d3d00ff80ea8f"
+string(32) "00ff80ea8f3d3d3d3d3d3d3d3d3d3d3d"
+string(32) "3d3d3d3d3d00ff80ea8f3d3d3d3d3d3d"
+
+DONE