Re: [avr-chat] Type promotion and shift operators

[David A. Lyons]

On Feb 2, 2011, at 1:28 PM, Rick Mann wrote:
> ... according to my K&R C book (which you seem to be saying is out of date), 
> the smaller type is promoted to a larger type when the types on an operator 
> are different. ...

C99 spec: <http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1256.pdf>

Page 84
> Bitwise shift operators
> ...
> The integer promotions are performed on each of the operands. The type of the 
> result is that of the promoted left operand. 
> ...

And from page 43, "the integer promotions" means:
> If an int can represent all values of the original type, the value is 
> converted to an int; otherwise, it is converted to an unsigned int. These are 
> called the integer promotions. All other types are unchanged by the integer 
> promotions.

Cheers,

--Dave