diff --git a/Zend/zend_long.h b/Zend/zend_long.h
index 3796f1c5ababb..32dd10e86ca01 100644
--- a/Zend/zend_long.h
+++ b/Zend/zend_long.h
@@ -34,6 +34,7 @@ typedef uint64_t zend_ulong;
 typedef int64_t zend_off_t;
 # define ZEND_LONG_MAX INT64_MAX
 # define ZEND_LONG_MIN INT64_MIN
+# define ZEND_LONG_SAFE_MAX (2ULL << 52U)-1U
 # define ZEND_ULONG_MAX UINT64_MAX
 # define Z_L(i) INT64_C(i)
 # define Z_UL(i) UINT64_C(i)
@@ -44,6 +45,7 @@ typedef uint32_t zend_ulong;
 typedef int32_t zend_off_t;
 # define ZEND_LONG_MAX INT32_MAX
 # define ZEND_LONG_MIN INT32_MIN
+# define ZEND_LONG_SAFE_MAX INT32_MAX
 # define ZEND_ULONG_MAX UINT32_MAX
 # define Z_L(i) INT32_C(i)
 # define Z_UL(i) UINT32_C(i)
diff --git a/main/main.stub.php b/main/main.stub.php
index 3359d4a1cd0bf..755d2c44c6766 100644
--- a/main/main.stub.php
+++ b/main/main.stub.php
@@ -163,6 +163,11 @@
  * @cvalue SIZEOF_ZEND_LONG
  */
 const PHP_INT_SIZE = UNKNOWN;
+/**
+ * @var int
+ * @cvalue ZEND_LONG_SAFE_MAX
+ */
+const PHP_INT_MAX_SAFE = UNKNOWN;
 /**
  * @var int
  * @cvalue FD_SETSIZE
diff --git a/main/main_arginfo.h b/main/main_arginfo.h
index 922af3aff0629..4b6caa88b132e 100644
--- a/main/main_arginfo.h
+++ b/main/main_arginfo.h
@@ -1,5 +1,5 @@
 /* This is a generated file, edit the .stub.php file instead.
- * Stub hash: cb5c9a3e48b18a773264378099267550ca9e4fc1 */
+ * Stub hash: 0cf6005e93a1fc95b221f8450a0daef6caae7e63 */
 
 static void register_main_symbols(int module_number)
 {
@@ -36,6 +36,7 @@ static void register_main_symbols(int module_number)
 	REGISTER_LONG_CONSTANT("PHP_INT_MAX", ZEND_LONG_MAX, CONST_PERSISTENT);
 	REGISTER_LONG_CONSTANT("PHP_INT_MIN", ZEND_LONG_MIN, CONST_PERSISTENT);
 	REGISTER_LONG_CONSTANT("PHP_INT_SIZE", SIZEOF_ZEND_LONG, CONST_PERSISTENT);
+	REGISTER_LONG_CONSTANT("PHP_INT_MAX_SAFE", ZEND_LONG_SAFE_MAX, CONST_PERSISTENT);
 	REGISTER_LONG_CONSTANT("PHP_FD_SETSIZE", FD_SETSIZE, CONST_PERSISTENT);
 	REGISTER_LONG_CONSTANT("PHP_FLOAT_DIG", DBL_DIG, CONST_PERSISTENT);
 	REGISTER_DOUBLE_CONSTANT("PHP_FLOAT_EPSILON", DBL_EPSILON, CONST_PERSISTENT);
diff --git a/tests/lang/constants/PHP_INT_32bit.phpt b/tests/lang/constants/PHP_INT_32bit.phpt
index 624ceb43431ca..1e50afdf150d2 100644
--- a/tests/lang/constants/PHP_INT_32bit.phpt
+++ b/tests/lang/constants/PHP_INT_32bit.phpt
@@ -1,5 +1,5 @@
 --TEST--
-Test PHP_INT_MIN, PHP_INT_MAX and PHP_INT_SIZE (32-bit)
+Test PHP_INT_MIN, PHP_INT_MAX, PHP_INT_MAX_SAFE and PHP_INT_SIZE (32-bit)
 --SKIPIF--
 <?php if (PHP_INT_SIZE !== 4)
     die("skip this test is for 32-bit platforms only"); ?>
@@ -8,10 +8,14 @@ Test PHP_INT_MIN, PHP_INT_MAX and PHP_INT_SIZE (32-bit)
 
 var_dump(PHP_INT_MIN);
 var_dump(PHP_INT_MAX);
+var_dump(PHP_INT_MAX_SAFE);
+var_dump(PHP_INT_MAX_SAFE === PHP_INT_MAX);
 var_dump(PHP_INT_SIZE);
 
 ?>
 --EXPECT--
 int(-2147483648)
 int(2147483647)
+int(2147483647)
+bool(true)
 int(4)
diff --git a/tests/lang/constants/PHP_INT_64bit.phpt b/tests/lang/constants/PHP_INT_64bit.phpt
index 7756e59a3f0bf..673b47f6f0b84 100644
--- a/tests/lang/constants/PHP_INT_64bit.phpt
+++ b/tests/lang/constants/PHP_INT_64bit.phpt
@@ -1,5 +1,5 @@
 --TEST--
-Test PHP_INT_MIN, PHP_INT_MAX and PHP_INT_SIZE (64-bit)
+Test PHP_INT_MIN, PHP_INT_MAX, PHP_INT_MAX_SAFE and PHP_INT_SIZE (64-bit)
 --SKIPIF--
 <?php if (PHP_INT_SIZE !== 8)
     die("skip this test is for 64-bit platforms only"); ?>
@@ -8,10 +8,14 @@ Test PHP_INT_MIN, PHP_INT_MAX and PHP_INT_SIZE (64-bit)
 
 var_dump(PHP_INT_MIN);
 var_dump(PHP_INT_MAX);
+var_dump(PHP_INT_MAX_SAFE);
+var_dump(PHP_INT_MAX_SAFE === (2 << 52)-1);
 var_dump(PHP_INT_SIZE);
 
 ?>
 --EXPECT--
 int(-9223372036854775808)
 int(9223372036854775807)
+int(9007199254740991)
+bool(true)
 int(8)