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Re: Is it a bug when use “<<”if the operator is out of the size "0~63"
- From: Jonathan Wakely <jwakely dot gcc at gmail dot com>
- To: Yang Yueming <yueming dot yang at huawei dot com>
- Cc: "gcc at gcc dot gnu dot org" <gcc at gcc dot gnu dot org>
- Date: Fri, 24 Feb 2012 09:11:45 +0000
- Subject: Re: Is it a bug when use “<<”if the operator is out of the size "0~63"
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On 24 February 2012 08:34, Yang Yueming wrote:
> The result of xyz should be "0"ïbut it is "2468acf123579bc" ,same as Âxyz = abc << 1,Why?
The C standard says it's undefined behaviour:
"If the value of the right operand is negative or is greater than or
equal to the width of the promoted left operand, the behavior is