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Date: Thu, 17 Feb 2011 06:31:00 -0000
Message-ID: <AANLkTike2aAAB6GM6GS7txmVN09fCThL4Lgr9uF-bEBv@mail.gmail.com>
Subject: Re: infinite for-loop and related question
From: Jonathan Wakely <jwakely.gcc@gmail.com>
To: Thomas Martitz <thomas.martitz@student.htw-berlin.de>
Cc: gcc-help@gcc.gnu.org
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On 16 February 2011 23:02, Thomas Martitz  wrote:
> Am 16.02.2011 22:49, schrieb Jonathan Wakely:
>>
>> On 16 February 2011 21:37, Bob Plantz wrote:
>>>
>>> On 02/16/2011 12:41 PM, Jason Mancini wrote:
>>>>
>>>> Though I still find the output of this odd:
>>>>
>>>> =A0 for (char i(1); i>0; ++i)
>>>> =A0 =A0 printf("%d %d\n", i, sizeof(i));
>>>>
>>>> ...
>>>> 362195 1
>>>> 362196 1
>>>> 362197 1
>>>> ...
>>>>
>>>> For very large values of char! =A0^_^
>>>>
>>>> Jason
>>>
>>> That's odd. With g++ 4.4.5 on an x86-64 machine in 64-bit mode I get:
>>>
>>> ---
>>> 125 1
>>> 126 1
>>> 127 1
>>>
>>> which is what I would expect. That is, i is a (signed) char, and when it
>>> goes over 127 it becomes a negative number, so the loop terminates.
>>
>> That would be the expected result if char was unsigned.
>
> Not exactly, no? An unsiged char goes to 255.
>
> Best regards.
>

Well yeah, of course. But the value goes to zero and the loop terminates.