Bug #72100 [Opn->Asn]: implode() inserts garbage into resulting string when joins very big integer

Edit report at https://bugs.php.net/bug.php?id=72100&edit=1 ID: 72100 Updated by: pajoye@php.net Reported by: mikhail dot galanin at yahoo dot com Summary: implode() inserts garbage into resulting string when joins very big integer -Status: Open +Status: Assigned Type: Bug Package: Scripting Engine problem Operating System: SLES x86_64 PHP Version: 7.0.5 -Assigned To: +Assigned To: ab Block user comment: N Private report: N New Comment: err It is big number related. I was checking two times the same script. Assigning to Anatol, he knows that area well :) Previous Comments: ------------------------------------------------------------------------ [2016-04-26 07:26:51] pajoye@php.net It seems to be unrelated to big numbers. shorter script: $a1 = ['INSERT IGNORE INTO', 'Table', 999999999999999999, PHP_INT_MIN, PHP_INT_MAX]; $a2 = ['INSERT IGNORE INTO', 'Table', 1, 2, 3]; $str1 = implode(' ', $a1); $str2 = implode(' ', $a1); var_dump($str1, $str2); It keeps the ending \0 for the 1st string, "INSERT IGNORE INTO<bh:00> Ta" (little literal hexdump). ------------------------------------------------------------------------ [2016-04-25 09:13:25] mikhail dot galanin at yahoo dot com Here is .phpt for the issue: --TEST-- Test implode() function, problems with big numbers --SKIPIF-- <?php if (PHP_INT_SIZE != 8) die("skip this test is for 64bit platform only"); ?> --FILE-- <?php /* Prototype : string vsprintf(string $format , array $args) * Description: Return a formatted string * Source code: ext/standard/formatted_print.c */ /* very long number */ var_dump( implode(" ", ["hello long", 999999999999999999, PHP_INT_MAX] ) ); var_dump( implode(" ", ["hello negative long", -999999999999999999, PHP_INT_MIN] ) ); var_dump( implode(" ", ["hello small long", -101, -100, -99, -90, -11, -10, -9, -1, 0, 1, 2, 9, 10, 11, 90, 99, 100, 101] ) ); echo "Done\n"; ?> --EXPECTF-- string(49) "hello long 999999999999999999 9223372036854775807" string(60) "hello negative long -999999999999999999 -9223372036854775808" string(76) "hello small long -101 -100 -99 -90 -11 -10 -9 -1 0 1 2 9 10 11 90 99 100 101" Done ------------------------------------------------------------------------ [2016-04-25 09:09:06] mikhail dot galanin at yahoo dot com Description: ------------ In the implode() implementation, there's an optimisation that operates when input array contains long's. This optimisation relays on the fact that log10(num) returns digit number of string representation of "num". Even though mathematically it is correct there an issue when num consist of more than 14 nines (i.e. 99999999999999999). In this case the log10 is rounded up and actual result gets wrong. Test script: --------------- $a = [ 'INSERT IGNORE INTO ', 'Table', (999999999999999999), PHP_INT_MIN, PHP_INT_MAX ]; $str = implode(' ', $a); echo json_encode(["str" => $str]); Expected result: ---------------- {"str":"INSERT IGNORE INTO Table 999999999999999999 -9223372036854775808 9223372036854775807"} Actual result: -------------- {"str":"INSERT IGNORE INTO \u0000 Table 999999999999999999 -9223372036854775808 9223372036854775807"} ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=72100&edit=1