PING: Re: Fix build failure with JAVAC_MAX_WARNINGS=true in sun/nio/cs

[Florian Weimer]

* Andrew John Hughes:

> On 7 June 2010 23:04, Xueming Shen <xueming.shen at oracle.com> wrote:
>> Hi Andrew,
>>
>> 6959197: When building with JAVAC_MAX_WARNINGS=true, the build fails in
>> sun/nio/cs due to the use of -Werror
>>
>> (1)sun/io/ByteTocharISO2022JP.java
>>   #129,  #151
>>
>>   if ((byte1 & (byte)0x80) != 0){
>>
>>       if ((byte2 & (byte)0x80) != 0){
>>
>>
>> (byte) casting is not necessary as well?
>>
>
> It's necessary.  0x80 is an integer literal
> (http://java.sun.com/docs/books/jls/third_edition/html/lexical.html#3.10.1)
> which requires a lossy narrowing conversion to byte
> (http://java.sun.com/docs/books/jls/third_edition/html/conversions.html#5.1.3)

Doesn't the & operator promote its arguments to int anyway?  I don't
think the cast to byte makes a difference here because it does not
matter if 0x80 is sign-extended or zero-extended.

It might be more efficient to use "byte1 < 0" and "byte2 < 0" instead.

-- 
Florian Weimer                <fweimer at bfk.de>
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