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[me22]

2009/6/16 Rafael Espindola <espindola at google.com>
>
> > +  <li><a href="http://nondot.org/sabre/LLVMNotes/BuiltinUnreachable.txt">Value
> > +      assertions</a> (also <a href="http://llvm.org/PR810">PR810</a>).</li>
> >  </ol>
>
> The example
>
>   int test(char *f) {
>     if (*f)
>       __builtin_unreachable ();
>     return f ? 1 : 0;
>   }
>
>
> should probably be
>
>   int test(char *f) {
>     if (*f)
>       __builtin_unreachable ();
>     return *f ? 0 : 1;
>   }
>
> for it to be reduced to "return 1".
>

Well arguably just this is enough to be reduced to "return 1":

  int test(char *f) {
    *f;
    return f ? 1 : 0;
  }

But I agree, it probably should be made more obvious.  Why not just
this, though?:

  int test(char c) {
    if (c)
      __builtin_unreachable ();
    return !c;
  }

~ Scott