With OpenWatcom we (a colleague and myself) receive the following warning:
Warning! W124: Comparison result always 0
The code we have is of course part of a larger project, but the piece of code that results in a warning is equivalent to this:
typedef unsigned __int64 uint64_t; /* typedef'd depends on compiler/platform */
uint64_t x;
/* x gets a value */
if (x > 0xFFFFFFFFU) /* <-- warning */
{
/* do something */
}
I would think that the literal value should be promoted to the integer type of x, but evidently it isn't.
What gives? Do integer promotion rules not apply to 64bit integers?
Are the only solutions an explicit cast ((x > (uint64_t)0xFFFFFFFFU)) or something ala comparison to 0xFFFFFFFFULL? The typecast will actually make the warning vanish, but I didn't look at the produced code to verify that it still makes sense.
Notes:
- The code does not compile as C99, it uses something between C89 and C99 (e.g. includes C++ style single-line comments).
- Watcom and OpenWatcom are just compilers used by some of our team members and OpenWatcom was the only compiler to complain there.
