Bug #68657 [Asn->Csd]: Reading 4 byte floats with Mysqli and libmysqlclient has rounding errors

Edit report at https://bugs.php.net/bug.php?id=68657&edit=1 ID: 68657 Updated by: keyur@php.net Reported by: keyur@php.net Summary: Reading 4 byte floats with Mysqli and libmysqlclient has rounding errors -Status: Assigned +Status: Closed Type: Bug Package: MySQLi related Operating System: Any PHP Version: 5.5.20 Assigned To: keyur Block user comment: N Private report: N New Comment: The fix for this bug has been committed. Snapshots of the sources are packaged every three hours; this change will be in the next snapshot. You can grab the snapshot at http://snaps.php.net/. For Windows: http://windows.php.net/snapshots/ Thank you for the report, and for helping us make PHP better. Previous Comments: ------------------------------------------------------------------------ [2014-12-26 21:55:07] keyur@php.net Description: ------------ This is similar to the bug 67839. The patch for that was only done to the mysqlnd driver and needs to be reapplied to the libmysqlclient driver as well. Test script: --------------- On a MySQL DB, run the following queries: CREATE TABLE test(id INT PRIMARY KEY, fp4 FLOAT, fp8 DOUBLE) ENGINE = InnoDB; INSERT INTO test(id, fp4, fp8) VALUES (1, 9.9999, 9.9999) Now using mysqli, SELECT the one row out: $id = null; $fp4 = null; $fp8 = null; $stmt = mysqli_prepare($link, "SELECT * FROM test"); mysqli_stmt_bind_result($stmt, $id, $fp4, $fp8); mysqli_stmt_execute($stmt); mysqli_stmt_fetch($stmt); $test = array($id, $fp4, $fp8); var_dump($test); Expected result: ---------------- It should be: array(3) { [0]=> int(1) [1]=> float(9.9999) [2]=> float(9.9999) } Actual result: -------------- The output will be: array(3) { [0]=> int(1) [1]=> float(9.9998998642) [2]=> float(9.9999) } ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=68657&edit=1