clang/test/SemaCXX/char8_t.cpp

   1 // RUN: %clang_cc1 -fchar8_t -std=c++17 -verify %s
   2 // RUN: %clang_cc1 -std=c++2a -verify=expected %s
   3 // RUN: %clang_cc1 -std=c++2a -verify=expected -fno-signed-char %s
   4
   5
   6 char8_t a = u8'a';
   7 char8_t b[] = u8"foo";
   8 char8_t c = 'a';
   9 char8_t d[] = "foo"; // expected-error {{initializing 'char8_t' array with plain string literal}} expected-note {{add 'u8' prefix}}
  10
  11 char e = u8'a';
  12 char g = 'a';
  13 char h[] = "foo";
  14
  15 unsigned char i[] = u8"foo";
  16 unsigned char j[] = { u8"foo" };
  17 char k[] = u8"foo";
  18 char l[] = { u8"foo" };
  19 signed char m[] = u8"foo"; // expected-error {{initialization of char array with UTF-8 string literal is not permitted}}
  20 signed char n[] = { u8"foo" }; // expected-error {{cannot initialize an array element of type 'signed char' with an lvalue of type 'const char8_t[4]'}}
  21
  22 const unsigned char* uptr = u8"foo"; // expected-error {{cannot initialize}}
  23 const signed char* sptr = u8"foo"; // expected-error {{cannot initialize}}
  24 const char* ptr = u8"foo"; // expected-error {{cannot initialize}}
  25
  26 template <typename T>
  27 void check_values() {
  28   constexpr T c[] = {0, static_cast<T>(0xFF), 0x42};
  29   constexpr T a[] = u8"\x00\xFF\x42";
  30
  31   static_assert(a[0] == c[0]);
  32   static_assert(a[1] == c[1]);
  33   static_assert(a[2] == c[2]);
  34 }
  35
  36 void call_check_values() {
  37   check_values<char>();
  38   check_values<unsigned char>();
  39 }
  40
  41 void disambig() {
  42   char8_t (a) = u8'x';
  43 }
  44
  45 void operator""_a(char);
  46 void operator""_a(const char*, decltype(sizeof(0)));
  47
  48 void test_udl1() {
  49   int &x = u8'a'_a; // expected-error {{no matching literal operator}}
  50   float &y = u8"a"_a; // expected-error {{no matching literal operator}}
  51 }
  52
  53 int &operator""_a(char8_t);
  54 float &operator""_a(const char8_t*, decltype(sizeof(0)));
  55
  56 void test_udl2() {
  57   int &x = u8'a'_a;
  58   float &y = u8"a"_a;
  59 }
  60
  61 template<typename E, typename T> void check(T &&t) {
  62   using Check = E;
  63   using Check = T;
  64 }
  65 void check_deduction() {
  66   check<char8_t>(u8'a');
  67   check<const char8_t(&)[5]>(u8"a\u1000");
  68 }
  69
  70 static_assert(sizeof(char8_t) == 1);
  71 static_assert(char8_t(-1) > 0);
  72 static_assert(u8"\u0080"[0] > 0);
  73
  74 namespace ambiguous {
  75
  76 struct A {
  77         char8_t s[10];
  78 };
  79 struct B {
  80   char s[10];
  81 };
  82
  83 void f(A); // expected-note {{candidate}}
  84 void f(B); // expected-note {{candidate}}
  85
  86 int test() {
  87   f({u8"foo"}); // expected-error {{call to 'f' is ambiguous}}
  88 }
  89
  90 }