Fix #81500: Interval serialization regression since 7.3.14 / 7.4.2

While it may not be desired, `DateInterval::$f` supports negative
values, at least with regard to calculations.  We still need to guard
from assigning double values which are out of range for signed 64bit
integers (which would be undefined behavior).  zend_dval_to_lval() does
this by returning `0` instead of triggering UB.  This way we can avoid
setting the invalid marker, which doesn't work as expected anyway.

We must not do that only for unserialization, but also when the property
is set in the first place.

We need to adapt some of the existing tests wrt. this behavior.  In
particular, we check for an arbitrary value in bug79015.phpt, to cater
to differences between 32bit and 64bit architectures.

Closes GH-7575.

NEWS

@@ -6,6 +6,10 @@ PHP                                                                        NEWS
   . Fixed bug #81518 (Header injection via default_mimetype / default_charset).
     (cmb)
 
+- Date:
+  . Fixed bug #81500 (Interval serialization regression since 7.3.14 / 7.4.2).
+    (cmb)
+
 - MySQLi:
   . Fixed bug #81494 (Stopped unbuffered query does not throw error). (Nikita)
 

ext/date/php_date.c

@@ -4331,7 +4331,7 @@ static zval *date_interval_write_property(zval *object, zval *member, zval *valu
 		SET_VALUE_FROM_STRUCT(i, "i");
 		SET_VALUE_FROM_STRUCT(s, "s");
 		if (strcmp(Z_STRVAL_P(member), "f") == 0) {
-			obj->diff->us = zval_get_double(value) * 1000000;
+			obj->diff->us = zend_dval_to_lval(zval_get_double(value) * 1000000.0);
 			break;
 		}
 		SET_VALUE_FROM_STRUCT(invert, "invert");
@@ -4468,12 +4468,8 @@ static int php_date_interval_initialize_from_hash(zval **return_value, php_inter
 	PHP_DATE_INTERVAL_READ_PROPERTY("s", s, timelib_sll, -1)
 	{
 		zval *z_arg = zend_hash_str_find(myht, "f", sizeof("f") - 1);
-		(*intobj)->diff->us = -1000000;
 		if (z_arg) {
-			double val = zval_get_double(z_arg) * 1000000;
-			if (val >= 0 && val < 1000000) {
-				(*intobj)->diff->us = val;
-			}
+			(*intobj)->diff->us = zend_dval_to_lval(zval_get_double(z_arg) * 1000000.0);
 		}
 	}
 	PHP_DATE_INTERVAL_READ_PROPERTY("weekday", weekday, int, -1)

ext/date/tests/bug53437_var3.phpt

@@ -44,6 +44,6 @@ object(DateInterval)#%d (16) {
   ["have_special_relative"]=>
   int(0)
   ["f"]=>
-  float(-1)
+  float(0)
 }
 ==DONE==

ext/date/tests/bug53437_var5.phpt

@@ -44,6 +44,6 @@ object(DateInterval)#%d (16) {
   ["have_special_relative"]=>
   int(0)
   ["f"]=>
-  float(-1)
+  float(0)
 }
 ==DONE==

ext/date/tests/bug73091.phpt

@@ -28,7 +28,7 @@ object(DateInterval)#%d (16) {
   ["s"]=>
   int(-1)
   ["f"]=>
-  float(-1)
+  float(0)
   ["weekday"]=>
   int(-1)
   ["weekday_behavior"]=>

ext/date/tests/bug79015.phpt

@@ -20,7 +20,7 @@ object(DateInterval)#%d (16) {
   ["s"]=>
   int(0)
   ["f"]=>
-  float(-1)
+  float(%f)
   ["weekday"]=>
   int(0)
   ["weekday_behavior"]=>

ext/date/tests/bug81500.phpt

@@ -0,0 +1,16 @@
+--TEST--
+Bug #81500 (Interval serialization regression since 7.3.14 / 7.4.2)
+--FILE--
+<?php
+$interval = new DateInterval('PT1S');
+$interval->f = -0.000001;
+var_dump($interval->s, $interval->f);
+
+$interval = unserialize(serialize($interval));
+var_dump($interval->s, $interval->f);
+?>
+--EXPECT--
+int(1)
+float(-1.0E-6)
+int(1)
+float(-1.0E-6)

ext/standard/tests/serialize/bug69425.phpt

@@ -40,7 +40,7 @@ array(2) {
     ["s"]=>
     int(-1)
     ["f"]=>
-    float(-1)
+    float(0)
     ["weekday"]=>
     int(-1)
     ["weekday_behavior"]=>