Is `(bool)true` Always Equivalent to `(int)1` in C ?

Type Casting in C Expressions: (bool)true and (int)1

In C , it is a common practice to use typecasting to convert data from one type to another. This question explores whether we can safely assume the equivalence of (bool)true and (int)1 in C compilers.

The Equivalence

The conversion from bool to int is defined by the C standard in section 4.7 [conv.integral] / 4. It states that if the source type is bool, the value true is converted to one. This means that in the expression (bool)true == (int)1, the bool value will be promoted to an int and will have a value of 1.

Redundant Casting

The casts in the expression (bool)true == (int)1 are technically redundant. The bool value will be automatically promoted to an int by the compiler, and the comparison will work as expected without the explicit casts.

Compiler Compatibility

The equivalence between (bool)true and (int)1 is guaranteed by the C standard. As such, it is a safe assumption to make for any C compiler that adheres to the standard.

Conclusion

In C , we can safely assume (bool)true == (int)1 for all C compilers that follow the C standard. The typecasts are redundant and can be omitted without affecting the result of the comparison.

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