Bug #79595 [PATCH]: zend_init_fpu() alters FPU precision

Edit report at https://bugs.php.net/bug.php?id=79595&edit=1 ID: 79595 Patch added by: cmb@php.net Reported by: v-yitam at microsoft dot com Summary: zend_init_fpu() alters FPU precision Status: Assigned Type: Bug Package: Math related Operating System: Alpine Linux PHP Version: 7.4.5 Assigned To: cmb Block user comment: N Private report: N New Comment: The following pull request has been associated: Patch Name: Fix #79595: zend_init_fpu() alters FPU precision On GitHub: https://github.com/php/php-src/pull/5602 Patch: https://github.com/php/php-src/pull/5602.patch Previous Comments: ------------------------------------------------------------------------ [2020-05-20 16:53:08] v-yitam at microsoft dot com The patch seems to fix the issue after the preliminary round of testing in Alpine Linux with PHP 7.4.5. Congratulations! Please let us know when this patch will be merged to a stable release. ------------------------------------------------------------------------ [2020-05-20 15:56:14] v-yitam at microsoft dot com My pleasure! Will get back to you later. ------------------------------------------------------------------------ [2020-05-20 15:50:03] cmb@php.net A possible fix might be <https://github.com/php/php-src/pull/5602>. Could you please try that, @yitam? ------------------------------------------------------------------------ [2020-05-20 15:20:01] v-yitam at microsoft dot com This floating point calculation issue happens in Alpine Linux only, so we are targeting 64-bit builds for Linux only. Thanks for considering! ------------------------------------------------------------------------ [2020-05-20 11:09:56] nikic@php.net Are you interested in this for 32-bit or 64-bit builds? I think we can safely disable this code if compiling under __SSE__, because we know that PHP itself will not use x87 FPU in that case. For 32-bit builds targeting x87 FPU, I don't think we want to change this, as we do want normal floating point operations to be based on double precision. ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=79595 -- Edit this bug report at https://bugs.php.net/bug.php?id=79595&edit=1