[PATCH] PR 7776: Warn about if ("abc" < "xyz") ...

[Daniel Jacobowitz]

On Sun, Jun 05, 2005 at 10:42:15AM -0600, Roger Sayle wrote:
> +   if (TREE_CODE_CLASS (code) == tcc_comparison
> +       && (TREE_CODE (arg1.value) == STRING_CST
> + 	  || TREE_CODE (arg2.value) == STRING_CST))
> +     warning (OPT_Wstring_literal_comparison,
> + 	     "comparison with string literal");
> +
>     unsigned_conversion_warning (result.value, arg1.value);
>     unsigned_conversion_warning (result.value, arg2.value);
>     overflow_warning (result.value);
> 

So, all comparisons in which either side is a string literal.  I don't
think that's a good choice.  What about this:

  if ("foo" == NULL)

Maybe there are no other interesting special cases besides == 0 and !=
0.

-- 
Daniel Jacobowitz
CodeSourcery, LLC