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CHAPTER 4 TYPE CONVERSIONS

User’s Manual U15556EJ1V0UM

(3) Usual arithmetic type conversions

Types obtained as a result of operations on arithmetic type data have a wide range of values.

The type conversion of the operation result is performed as follows.

•

If either one of the operands has long double type, the other operand is converted to long double type.

•

If either one of the operands has double type, the other operand is converted to double type.

•

If either one of the operands has float type, the other operand is converted to float type.

In cases other than above, general integer expansion is performed for both operands according to the following

rules. Figure 4-1 shows the rules.

Figure 4-1. Usual Arithmetic Type Conversions

unsigned long int

unsigned int

int

long int

If either of the two operands is unsigned long int type, or if one

operand is long int type and the other is unsigned int type

and the value of unsigned int type cannot be represented by long int type.

both operands will be converted to unsigned long int type.

In cases other than above, if one operand is long int type and if the value of

the other operand can be represented by long int type, the other operand will be

converted to long int type.

In cases other than above, if one operand is unsigned int type, the other operand

will be converted to unsigned int type.

In cases other than above, both operands will have int type.

In this compiler, the conversion to int type can be intentionally disabled by a compile condition (optimizing

option) (For details, refer to CC78K4 C Compiler Operation User’s Manual (U15557E) CHAPTER 5

COMPILER OPTIONS).

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