Re: g++ bug

[Ben Elliston]

>>>>> "Ron" == Ron Lancaster <address@hidden> writes:

  Ron> The following code generates an error message saying that the
  Ron> condition is always true but, for the data here, the condition
  Ron> is false and No is printed. The compiler is running under
  Ron> Solaris and the version is gcc version 2.95.3 20010315

  Ron> The error message is --- test.cpp: In function `int main()':
  Ron> test.cpp:9: warning: comparison is always true due to limited
  Ron> range of data type 

  Ron>    unsigned short IR = 0x7000;
  [...]
  Ron>    if((IR >= 0x0000 && IR <= 0x6FFF) || (IR >= 0x8FFF && IR <= 0xEFFF))

The warning (not an error) message pertains strictly to the first
subexpression in your if expression: (IR >= 0x0000).  Because IR is
unsigned, it is always true that IR >= 0.

Consider rewriting as:

        if ((IR < 0x6FFF) || (IR >= 0x8FFF && IR < 0xEFFF))
          { .. }

Cheers, Ben