ID: 19733
Updated by: [EMAIL PROTECTED]
Reported By: [EMAIL PROTECTED]
-Status: Open
+Status: Closed
Bug Type: Math related
Operating System: Windows 2000
PHP Version: 4.2.3
New Comment:
Fixed in CVS. There were also a number of other issues regarding
overflow detection which have been addressed now.
Previous Comments:
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[2002-10-03 08:05:47] [EMAIL PROTECTED]
Interesting catch.
The relevant code looks as following:
for (i = Z_STRLEN_P(arg); i > 0; i--) {
c = *s++;
digit = (c >= '0' && c <= '9') ? c - '0'
: (c >= 'A' && c <= 'Z') ? c - 'A' + 10
: (c >= 'a' && c <= 'z') ? c - 'a' + 10
: base;
if (digit >= base)
continue;
switch (mode) {
case 0: /* Integer */
onum = num;
num = num * base + digit;
fprintf(stderr, "num = %d, onum = %d\n", num, onum);
if (num > onum)
break; /* No overflow, continue */
fnum = onum;
mode = 1;
/* fall-through */
case 1: /* Float */
fnum = fnum * base + digit;
}
}
from ext/standard/math.c ( _php_math_basetozval ).
This code assumed that an overflow also occured when the newer 'num' ==
'onum'. "A" fix would be to change the comparison to be ">=" instead of
">" .
But I don't know the code well enough, someone else needs to check this
toroughly.
------------------------------------------------------------------------
[2002-10-03 05:33:36] [EMAIL PROTECTED]
hexdec('012345') should return int(74565), but instead it returns
float(74565), contrary to the documentation. This happens for all
numbers in strings I've tested that begin with 0, which does not
include non-hexadecimal characters which are taken to be 0, eg,
hexdec('q12345') returns int.
(Fixing the problem by casting the result to an (int) works fine. It
originally catched me out when I used array_flip on an array of
results, which demands integer or string keys.)
I'm not sure what the configure line is, but it's just a regular
install from the downloaded executable binary, with no extra modules
loaded. Since maths functions are in the PHP core, it hopefully won't
matter.
Thanks
Andrew Alderwick, United Kingdom
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Edit this bug report at http://bugs.php.net/?id=19733&edit=1
