Fix GH-16577: EG(strtod_state).freelist leaks with opcache.preload

This happens because on ZTS we execute `executor_globals_ctor` which reset the
`freelist` and `p5s` pointers, while on NTS we don't.
On NTS we can reuse the caches but on ZTS we can't, the easiest fix is
to call `zend_shutdown_strtod` when preloading is shut down.
This regressed in GH-13974 and therefore only exists in PHP 8.4 and
higher.

Closes GH-16602.

Author: nielsdos

NEWS

@@ -5,6 +5,8 @@ PHP                                                                        NEWS
 - Core:
   . Fixed bug GH-16574 (Incorrect error "undefined method" messages).
     (nielsdos)
+  . Fixed bug GH-16577 (EG(strtod_state).freelist leaks with opcache.preload).
+    (nielsdos)
 
 - GD:
   . Fixed bug GH-16559 (UBSan abort in ext/gd/libgd/gd_interpolation.c:1007).

ext/opcache/ZendAccelerator.c

@@ -4462,6 +4462,12 @@ static zend_result accel_preload(const char *config, bool in_child)
 		/* Release stored values to avoid dangling pointers */
 		zend_shutdown_executor_values(/* fast_shutdown */ false);
 
+		/* On ZTS we execute `executor_globals_ctor` which reset the freelist and p5s pointers, while on NTS we don't.
+		 * We have to clean up the memory before the actual request takes place to avoid a memory leak. */
+#ifdef ZTS
+		zend_shutdown_strtod();
+#endif
+
 		/* We don't want to preload constants.
 		 * Check that  zend_shutdown_executor_values() also destroys constants. */
 		ZEND_ASSERT(zend_hash_num_elements(EG(zend_constants)) == EG(persistent_constants_count));

ext/opcache/tests/gh16577.inc

@@ -0,0 +1,2 @@
+<?php
+var_dump(1.5);

ext/opcache/tests/gh16577.phpt

@@ -0,0 +1,20 @@
+--TEST--
+GH-16577 (EG(strtod_state).freelist leaks with opcache.preload)
+--INI--
+opcache.enable=1
+opcache.enable_cli=1
+opcache.optimization_level=-1
+opcache.preload={PWD}/gh16577.inc
+--EXTENSIONS--
+opcache
+--SKIPIF--
+<?php
+if (PHP_OS_FAMILY == 'Windows') die('skip Preloading is not supported on Windows');
+?>
+--FILE--
+<?php
+echo "Done\n";
+?>
+--EXPECT--
+float(1.5)
+Done