[Zlib-devel] zlib: Run-Time Check Failure #1 - A cast to smaller data type

[Mark Adler]

On Aug 27, 2007, at 5:09 AM, Glenn Randers-Pehrson wrote:
> Visual Studio say: Run-Time Check Failure #1 - A cast to smaller  
> data type
> has caused a loss of data. If this was intentional, you should mask  
> the
> source of the cast with the appropriate bitmask. For example: char  
> c = (i &
> 0xFF); Changing the code in this way will not affect the quality of  
> the
> resulting optimized code.

Glenn,

Thank you for the report.

Does Visual Studio have to be asked to produce this "check failure"?   
I'm wondering if this should be fixed, since it's not obvious that  
all compilers will optimize out the & 0xff.  I believe that there are  
many other places in zlib where the & 0xff is implicit in the  
assignment to a char.

Mark