if-statement with two checks with different data types

[Lundin]

ISO 9899:1999 6.5.8 Relational operators
"3 If both of the operands have arithmetic type, the usual arithmetic conversions are
performed."

ISO 9899:1999 6.3.1.8 Usual arithmetic conversions
... (rules for floats)

"Otherwise, the integer promotions are performed on both operands. Then the following rules are applied to the promoted operands:

If both operands have the same type, then no further conversion is needed.

Otherwise, if both operands have signed integer types or both have unsigned
integer types, the operand with the type of lesser integer conversion rank is
converted to the type of the operand with greater rank.

Otherwise, if the operand that has unsigned integer type has rank greater or
equal to the rank of the type of the other operand, then the operand with
signed integer type is converted to the type of the operand with unsigned
integer type.

Otherwise, if the type of the operand with signed integer type can represent
all of the values of the type of the operand with unsigned integer type, then
the operand with unsigned integer type is converted to the type of the
operand with signed integer type.

Otherwise, both operands are converted to the unsigned integer type
corresponding to the type of the operand with signed integer type."


If the above is different in C90, then please ignore my post. I suspect it is worded exactly the same, however.