Re: Cannot compile with _FILE_OFFSET_BITS = 64
On Mon, 31 Dec 2007 14:25:10 +0800, Scott.zhou wrote:
25 if (lseek(fd, 4*1024*1024*1024, SEEK_SET) == -1) { // integer
overflow
In this example, although I explicitly define _FILE_OFFSET_BITS 64, i
get the warning"integer overflow"
4 is an int. 1024 is an int. 1024 is an int. 1024 is an int. When you
multiply ints, you get an int, and the result must be within the range of
an int. Even if that int would later be converted to another type. You
first need to convert the 4 to a wider type, and then start multiplying.
.
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