Bug #79504 [Opn]: json_decode memory leak

Edit report at https://bugs.php.net/bug.php?id=79504&edit=1 ID: 79504 Updated by: sjon@php.net Reported by: lyrixx at lyrixx dot info Summary: json_decode memory leak Status: Open Type: Bug Package: *General Issues Operating System: linux PHP Version: 7.4.5 Block user comment: N Private report: N New Comment: this is not an issue with json, the same can be reproduced by doing simply: <?php ini_set('memory_limit', -1); function m(){ echo round(memory_get_usage() / 1024 / 1024, 2) . "\n"; } m(); $l=[]; for ($i = 0; $i < 2e6; $i++) array_push($l, (object)["url"=>"https://www.example.org/"]); m(); unset($l); m(); gc_mem_caches(); m(); gc_collect_cycles(); m(); Previous Comments: ------------------------------------------------------------------------ [2020-04-21 16:45:59] lyrixx at lyrixx dot info Description: ------------ Hello I notice a bug in json_decode(). With the following script, the memory is not reclaimed. But if I use json_decode($content, true); the memory is well reclaimed. By the way, I'm not sure it's an issue with JSON, may be it's only about objects Test script: --------------- <?php ini_set('memory_limit', -1); function m() { echo round(memory_get_usage() / 1024 / 1024, 2) . "\n"; } m(); $content = file_get_contents('https://gist.githubusercontent.com/lyrixx/3542faea462e5d101d0d755886ea79bd/raw/b83466f2dc61348e414d3507eeb5740f7751e8f3/file.json'); m(); $data = json_decode($content); m(); unset($content, $data); m(); gc_mem_caches(); m(); gc_collect_cycles(); m(); Expected result: ---------------- 0.56 75.01 754.69 0.56 0.56 0.56 Actual result: -------------- 0.56 75.01 817.65 16.55 16.55 16.55 ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=79504&edit=1