clang/test/CodeGenCXX/cxx1z-inline-variables.cpp

   1 // RUN: %clang_cc1 -std=c++1z %s -emit-llvm -o - -triple x86_64-linux-gnu | FileCheck %s
   2
   3 struct Q {
   4   // CHECK: @_ZN1Q1kE = linkonce_odr constant i32 5, comdat
   5   static constexpr int k = 5;
   6 };
   7 const int &r = Q::k;
   8
   9 int f();
  10
  11 // const does not imply internal linkage.
  12 // CHECK: @external_inline = linkonce_odr constant i32 5, comdat
  13 inline const int external_inline = 5;
  14 const int &use1 = external_inline;
  15
  16 // static still does, though.
  17 // CHECK: @_ZL15internal_inline = internal constant i32 5
  18 static inline const int internal_inline = 5;
  19 const int &use2 = internal_inline;
  20
  21 int a = f();
  22 // CHECK: @b = linkonce_odr global i32 0, comdat
  23 // CHECK: @_ZGV1b = linkonce_odr global i64 0, comdat($b)
  24 inline int b = f();
  25 int c = f();
  26
  27 // For compatibility with C++11 and C++14, an out-of-line declaration of a
  28 // static constexpr local variable promotes the variable to weak_odr.
  29 struct compat {
  30   static constexpr int a = 1;
  31   static constexpr int b = 2;
  32   static constexpr int c = 3;
  33   static inline constexpr int d = 4;
  34   static const int e = 5;
  35   static const int f = 6;
  36   static const int g = 7;
  37 };
  38 const int &compat_use_before_redecl = compat::b;
  39 const int compat::a;
  40 const int compat::b;
  41 const int compat::c;
  42 const int compat::d;
  43 const int compat::e;
  44 constexpr int compat::f;
  45 constexpr inline int compat::g;
  46 const int &compat_use_after_redecl1 = compat::c;
  47 const int &compat_use_after_redecl2 = compat::d;
  48 const int &compat_use_after_redecl3 = compat::g;
  49 // CHECK-DAG: @_ZN6compat1bE = weak_odr constant i32 2
  50 // CHECK-DAG: @_ZN6compat1aE = weak_odr constant i32 1
  51 // CHECK-DAG: @_ZN6compat1cE = weak_odr constant i32 3
  52 // CHECK-DAG: @_ZN6compat1dE = linkonce_odr constant i32 4
  53 // CHECK-DAG: @_ZN6compat1eE ={{.*}} constant i32 5
  54 // CHECK-DAG: @_ZN6compat1fE = weak_odr constant i32 6
  55 // CHECK-DAG: @_ZN6compat1gE = linkonce_odr constant i32 7
  56
  57 template<typename T> struct X {
  58   static int a;
  59   static inline int b;
  60   static int c;
  61   static const int d;
  62   static int e;
  63 };
  64 // CHECK: @_ZN1XIiE1aE = linkonce_odr global i32 10
  65 // CHECK: @_ZN1XIiE1bE ={{.*}} global i32 20
  66 // CHECK-NOT: @_ZN1XIiE1cE
  67 // CHECK: @_ZN1XIiE1dE = linkonce_odr constant i32 40
  68 // CHECK: @_ZN1XIiE1eE = linkonce_odr global i32 50
  69 template<> inline int X<int>::a = 10;
  70 int &use3 = X<int>::a;
  71 template<> int X<int>::b = 20;
  72 template<> inline int X<int>::c = 30;
  73 template<typename T> constexpr int X<T>::d = 40;
  74 template<typename T> inline int X<T>::e = 50;
  75 const int *use_x_int_d = &X<int>::d;
  76 const int *use_x_int_e = &X<int>::e;
  77
  78 template<typename T> struct Y;
  79 template<> struct Y<int> {
  80   static constexpr int a = 123;
  81   static constexpr int b = 456;
  82   static constexpr int c = 789;
  83 };
  84 // CHECK: @_ZN1YIiE1aE = weak_odr constant i32 123
  85 constexpr int Y<int>::a;
  86 // CHECK: @_ZN1YIiE1bE = linkonce_odr constant i32 456
  87 const int &yib = Y<int>::b;
  88 // CHECK-NOT: @_ZN1YIiE1cE
  89
  90 // CHECK-LABEL: define {{.*}}global_var_init
  91 // CHECK: call noundef i32 @_Z1fv
  92
  93 // CHECK-LABEL: define {{.*}}global_var_init{{.*}} comdat($b)
  94 // CHECK: load atomic {{.*}} acquire, align
  95 // CHECK: br
  96 // CHECK: __cxa_guard_acquire(i64* @_ZGV1b)
  97 // CHECK: br
  98 // CHECK: call noundef i32 @_Z1fv
  99 // CHECK: __cxa_guard_release(i64* @_ZGV1b)
 100
 101 // CHECK-LABEL: define {{.*}}global_var_init
 102 // CHECK: call noundef i32 @_Z1fv
 103
 104 template<typename T> inline int d = f();
 105 int e = d<int>;
 106
 107 // CHECK-LABEL: define {{.*}}global_var_init{{.*}}comdat
 108 // CHECK: _ZGV1dIiE
 109 // CHECK-NOT: __cxa_guard_acquire(i64* @_ZGV1b)
 110 // CHECK: call noundef i32 @_Z1fv
 111 // CHECK-NOT: __cxa_guard_release(i64* @_ZGV1b)
 112
 113 namespace PR35599 {
 114 struct Marker1 {};
 115 struct Marker2 {};
 116
 117 template <typename>
 118 struct Foo {
 119   struct Bar { Bar(); };
 120   inline static Bar bar;
 121 };
 122
 123 void run() {
 124   // All we want here are ODR uses. Anything that requires that the type is
 125   // complete is uninteresting.
 126 #pragma clang diagnostic push
 127 #pragma clang diagnostic ignored "-Wunused-value"
 128   Foo<Marker1>::bar;
 129 #pragma clang diagnostic pop
 130   static_cast<void>(Foo<Marker2>::bar);
 131 }
 132
 133 // CHECK-LABEL: define {{.*}}global_var_init{{.*}}comdat
 134 // CHECK: call void @_ZN7PR355993FooINS_7Marker1EE3BarC1Ev
 135 // CHECK-LABEL: define {{.*}}global_var_init{{.*}}comdat
 136 // CHECK: call void @_ZN7PR355993FooINS_7Marker2EE3BarC1Ev
 137 }