diff --git a/ext/json/JSON_parser.c b/ext/json/JSON_parser.c
index edb1adf005e..8eaf65e85c2 100644
--- a/ext/json/JSON_parser.c
+++ b/ext/json/JSON_parser.c
@@ -289,11 +289,11 @@ static void json_create_zval(zval **z, smart_str *buf, int type)
 
     if (type == IS_LONG)
     {
-		double d = zend_strtod(buf->c, NULL);
-		if (d > LONG_MAX || d < LONG_MIN) {
-			ZVAL_DOUBLE(*z, d);
+		long l = strtol(buf->c, NULL, 10);
+		if (l > LONG_MAX || l < LONG_MIN) {
+			ZVAL_DOUBLE(*z, zend_strtod(buf->c, NULL));
 		} else {
-			ZVAL_LONG(*z, (long)d);
+			ZVAL_LONG(*z, l);
 		}
     }
     else if (type == IS_DOUBLE)
diff --git a/ext/json/tests/bug47644.phpt b/ext/json/tests/bug47644.phpt
new file mode 100644
index 00000000000..5e996b69730
--- /dev/null
+++ b/ext/json/tests/bug47644.phpt
@@ -0,0 +1,43 @@
+--TEST--
+Bug #47644 (valid large integers are truncated)
+--SKIPIF--
+<?php
+  if (!extension_loaded('json')) die('skip: json extension not available');
+  if (PHP_INT_SIZE != 8) die("skip this test is for 64bit platform only");
+?>
+--FILE--
+<?php
+
+for ($i = 10000000000000000; $i < 10000000000000006; $i++) {
+	var_dump(json_decode("[$i]"));
+}
+
+
+echo "Done\n";
+?>
+--EXPECT--	
+array(1) {
+  [0]=>
+  int(10000000000000000)
+}
+array(1) {
+  [0]=>
+  int(10000000000000001)
+}
+array(1) {
+  [0]=>
+  int(10000000000000002)
+}
+array(1) {
+  [0]=>
+  int(10000000000000003)
+}
+array(1) {
+  [0]=>
+  int(10000000000000004)
+}
+array(1) {
+  [0]=>
+  int(10000000000000005)
+}
+Done