Re: Help me understand this compiler warning.

pete (in 44DF1184.CAE@xxxxxxxxxxxxxx) said:

| The left operand is uc[7], which is of type unsigned char.
|
| Your posted code doesn't do anything to prevent
| type unsigned char from being promoted to type int.
|
| Why do you think that in
| (uc[7] >> 4)
| that the left operand won't be promoted to int?
|
| "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."

You're absolutely right. I'm not sure how I managed it; but I looked
it up, read it carefully, and concluded that the unsigned char would
be promoted to an unsigned int - very wrong.

Thanks for getting me on track - and to the OP, my apologies for an
incorrect response.

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto


.

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