[Bug 24] Arithmetic operators are allowed on boolean expressions

[Walter Bright]

"Sean Kelly" <sean at f4.ca> wrote in message 
news:dur6p8$2ila$1 at digitaldaemon.com...
>>     bool x5; x5 += true;  // fails because x5+true is int, and int cannot 
>> be
>> implicitly converted to bool unless it is 0 or 1
>
> bool defaults to false/0, so x5 + true should equal 1, which should not 
> fail.

That would be true if x5 is a const, but it isn't, so it doesn't get 
constant folded. The same applies to the other examples.