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cstring-literalswchar-t

Is long string literal's type long int*?

According to the answers in this question, a literal like L"test" has type wchar_t[5]. But the following code with GCC seems to say something different:

int main()
{
    struct Test{char x;} s;
    s="Test"; // ok, char* as expected
    s=L"Test"; // ??? I'd expect wchar_t*
    return 0;
}

Here's how I compile it (gcc 5.2, but same results are with 4.5 and 4.8):

$ gcc test.c -o test -std=c99
test.c: In function ‘main’:
test.c:4:6: error: incompatible types when assigning to type ‘struct Test’ from type ‘char *’
     s="Test"; // ok, char* as expected
      ^
test.c:5:6: error: incompatible types when assigning to type ‘struct Test’ from type ‘long int *’
     s=L"Test"; // ??? I'd expect wchar_t*
      ^

Apparently, instead of the expected array of wchar_t I get array of long int. What's wrong here?

Solution

  • The type wchar_t is not a fundamental type, like char. It is an implementation-defined synonym of an integer type1.

    1 (Quoted from: ISO/IEC 9899:201x 7.19 Common definitions 2.)
    wchar_t which is an integer type whose range of values can represent distinct codes for all members of the largest extended character set specified among the supported locales;