clang/test/AST/Interp/bitfields.cpp

   1 // RUN: %clang_cc1 -fexperimental-new-constant-interpreter -Wno-bitfield-constant-conversion -verify %s
   2 // RUN: %clang_cc1 -verify=ref -Wno-bitfield-constant-conversion %s
   3 // RUN: %clang_cc1 -std=c++20 -fexperimental-new-constant-interpreter -Wno-bitfield-constant-conversion -verify %s
   4 // RUN: %clang_cc1 -std=c++20 -verify=ref -Wno-bitfield-constant-conversion %s
   5
   6 // expected-no-diagnostics
   7 // ref-no-diagnostics
   8
   9 namespace Basic {
  10   struct A {
  11     unsigned int a : 2;
  12     constexpr A() : a(0) {}
  13     constexpr A(int a) : a(a) {}
  14   };
  15
  16   constexpr A a{1};
  17   static_assert(a.a == 1, "");
  18
  19   constexpr A a2{10};
  20   static_assert(a2.a == 2, "");
  21
  22
  23   constexpr int storeA() {
  24     A a;
  25     a.a = 10;
  26
  27     return a.a;
  28   }
  29   static_assert(storeA() == 2, "");
  30
  31   constexpr int storeA2() {
  32     A a;
  33     return a.a = 10;
  34   }
  35   static_assert(storeA2() == 2, "");
  36
  37 #if __cplusplus >= 202002
  38   struct Init1 {
  39     unsigned a : 2 = 1;
  40   };
  41   constexpr Init1 I1{};
  42   static_assert(I1.a == 1, "");
  43
  44   struct Init2 {
  45     unsigned a : 2 = 100;
  46   };
  47   constexpr Init2 I2{};
  48   static_assert(I2.a == 0, "");
  49 #endif
  50
  51   struct Init3 {
  52     unsigned a : 2;
  53     constexpr Init3() : a(100) {}
  54   };
  55   constexpr Init3 I3{};
  56   static_assert(I3.a == 0, "");
  57 }
  58
  59 namespace Overflow {
  60   struct A {int c:3;};
  61
  62   constexpr int f() {
  63     A a1{3};
  64     return a1.c++;
  65   }
  66
  67   static_assert(f() == 3, "");
  68 }
  69
  70 namespace Compound {
  71   struct A {
  72     unsigned int a : 2;
  73     constexpr A() : a(0) {}
  74     constexpr A(int a) : a(a) {}
  75   };
  76
  77   constexpr unsigned add() {
  78     A a;
  79     a.a += 10;
  80     return a.a;
  81   }
  82   static_assert(add() == 2, "");
  83
  84   constexpr unsigned sub() {
  85     A a;
  86     a.a -= 10;
  87     return a.a;
  88   }
  89   static_assert(sub() == 2, "");
  90
  91   constexpr unsigned mul() {
  92     A a(1);
  93     a.a *= 5;
  94     return a.a;
  95   }
  96   static_assert(mul() == 1, "");
  97
  98   constexpr unsigned div() {
  99     A a(2);
 100     a.a /= 2;
 101     return a.a;
 102   }
 103   static_assert(div() == 1, "");
 104 }