clang/test/AST/Interp/references.cpp

   1 // RUN: %clang_cc1 -fexperimental-new-constant-interpreter -verify %s
   2 // RUN: %clang_cc1 -verify=ref %s
   3
   4
   5 constexpr int a = 10;
   6 constexpr const int &b = a;
   7 static_assert(a == b, "");
   8
   9 constexpr int assignToReference() {
  10   int a = 20;
  11   int &b = a;
  12
  13   b = 100;
  14   return a;
  15 }
  16 static_assert(assignToReference() == 100, "");
  17
  18
  19 constexpr void setValue(int &dest, int val) {
  20   dest = val;
  21 }
  22
  23 constexpr int checkSetValue() {
  24   int l = 100;
  25   setValue(l, 200);
  26   return l;
  27 }
  28 static_assert(checkSetValue() == 200, "");
  29
  30 constexpr int readLocalRef() {
  31   int a = 20;
  32   int &b = a;
  33   return b;
  34 }
  35 static_assert(readLocalRef() == 20, "");
  36
  37 constexpr int incRef() {
  38   int a = 0;
  39   int &b = a;
  40
  41   b = b + 1;
  42
  43   return a;
  44 }
  45 static_assert(incRef() == 1, "");
  46
  47
  48 template<const int &V>
  49 constexpr void Plus3(int &A) {
  50   A = V + 3;
  51 }
  52 constexpr int foo = 4;
  53
  54 constexpr int callTemplate() {
  55   int a = 3;
  56   Plus3<foo>(a);
  57   return a;
  58 }
  59 static_assert(callTemplate() == 7, "");
  60
  61
  62 constexpr int& getValue(int *array, int index) {
  63   return array[index];
  64 }
  65 constexpr int testGetValue() {
  66   int values[] = {1, 2, 3, 4};
  67   getValue(values, 2) = 30;
  68   return values[2];
  69 }
  70 static_assert(testGetValue() == 30, "");
  71
  72 constexpr const int &MCE = 20;
  73 static_assert(MCE == 20, "");
  74 static_assert(MCE == 30, ""); // expected-error {{static assertion failed}} \
  75                               // expected-note {{evaluates to '20 == 30'}} \
  76                               // ref-error {{static assertion failed}} \
  77                               // ref-note {{evaluates to '20 == 30'}}
  78
  79 constexpr int LocalMCE() {
  80   const int &m = 100;
  81   return m;
  82 }
  83 static_assert(LocalMCE() == 100, "");
  84 static_assert(LocalMCE() == 200, ""); // expected-error {{static assertion failed}} \
  85                                       // expected-note {{evaluates to '100 == 200'}} \
  86                                       // ref-error {{static assertion failed}} \
  87                                       // ref-note {{evaluates to '100 == 200'}}
  88
  89 struct S {
  90   int i, j;
  91 };
  92
  93 constexpr int RefToMemberExpr() {
  94   S s{1, 2};
  95
  96   int &j = s.i;
  97   j = j + 10;
  98
  99   return j;
 100 }
 101 static_assert(RefToMemberExpr() == 11, "");
 102
 103 struct Ref {
 104   int &a;
 105 };
 106
 107 constexpr int RecordWithRef() {
 108   int m = 100;
 109   Ref r{m};
 110   m = 200;
 111   return r.a;
 112 }
 113 static_assert(RecordWithRef() == 200, "");
 114
 115
 116 struct Ref2 {
 117   int &a;
 118   constexpr Ref2(int &a) : a(a) {}
 119 };
 120
 121 constexpr int RecordWithRef2() {
 122   int m = 100;
 123   Ref2 r(m);
 124   m = 200;
 125   return r.a;
 126 }
 127 static_assert(RecordWithRef2() == 200, "");