[Bug c++/11856] Wrong warning regarding assert

[o dot kullmann at swansea dot ac dot uk]

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11856



------- Additional Comments From o dot kullmann at swansea dot ac dot uk  2003-08-08 16:28 -------
Subject: Re:  Wrong warning regarding assert [Improved example]

> pinskia at gcc dot gnu dot org changed:
> 
>            What    |Removed                     |Added
> ----------------------------------------------------------------------------
>            Keywords|                            |diagnostic
> 
> 
> ------- Additional Comments From pinskia at gcc dot gnu dot org  2003-08-08 16:10 -------
> With this code:
> template <typename t>
> void f(t c) {
>   assert(0 <= c and c <= 2);
> }
> int main() {
>   f<unsigned char>(5);
> }
> I only get a warning on instantiation.
> 
>

I see, I oversimplified the problem a bit. Here is a better example:
------------------------------
#include <cassert>
template <typename Int, Int D>
void f(Int x) {
  assert(0 <= x and x <= D);
}
int main() {
  f<unsigned char, 2>(5);
}
-----------------------------
> g++ AssertWarning.cpp
AssertWarning.cpp: In function `void f(Int) [with Int = unsigned char, Int D =
   2]':
AssertWarning.cpp:7:   instantiated from here
AssertWarning.cpp:4: warning: comparison is always true due to limited range of
   data type
> ./a.out
a.out: AssertWarning.cpp:4: void f(Int) [with Int = unsigned char, Int D = 2]: Assertion `0 <= x and x <= D' failed.
Aborted.


Oliver