Why Does String Literal Conversion to `char*` Differ Between C and C ?

Discrepancies in String Literal Conversion to 'char*' Between C and C

In C, the conversion from a string literal to 'char*' is considered valid, while in C , it's deemed invalid. This seeming contradiction arises from the differences in how the languages treat string literals.

C : String Literal as 'const char*'

The C 11 Standard explicitly states that string literals should be treated as 'const char*'. This restriction stems from the fact that string literals are immutable, meaning any attempt to modify them would result in undefined behavior. As a safeguard, C restricts their manipulation by treating them as constant character arrays.

C: Implicit Conversion to 'char*'

In contrast, C allows the implicit conversion of string literals to 'char*'. This behavior is a remnant from earlier versions of C and has been deprecated. However, it remains valid in C due to the prevalence of existing code that relies on this conversion.

Explicit Cast in C

To address the invalidity of the implicit conversion in C , a cast can be added to explicitly convert the string literal to 'char*'. While this allows the code to compile, it's not a recommended solution as it does not fix the underlying issue of potentially modifying an immutable string literal.

Recommended Approach

To ensure code that is safe in both C and C , it's best to declare the pointer using the correct type, namely 'const char*'. This eliminates the possibility of unintentional modifications to the string literal and maintains consistency between the two languages.

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