Type Casting

Typecasting is a way of converting a variable or data from one data type to another data type.

Data will be truncated when the higher data type is converted into a lower data type.

Example

int x;
float y;

y = (float) x;  // Typecasting into a float data type

There are two types of casting:

Implicit casting

int main(){
    unsigned char data = 0x87 + 0xFF00;
}

Output

warning: unsigned conversion from ‘int’ to ‘unsigned char’ changes value from ‘65415’ to ‘135’ [-Woverflow]
   13 |     unsigned char data = 0x87 + 0xFF00;
      |                          ^~~~

Here, the compiler truncated the data of the second value 0XFF00 so it would fit into an unsigned char (255 bits), so the result is a variable with the value of data = 0x83

Explicit casting

int main(){
    unsigned char data = (unsigned char)(0x87 + 0xFF00);
}

Output

15:40:23 Build Finished. 0 errors, 0 warnings. (took 512ms)

Where now the compiler doesn't throw any warnings and the sum is performed correctly.

data = 65415