clang/test/CodeGenCXX/static-data-member-single-emission.cpp

   1 // RUN: %clang_cc1 %s -emit-llvm -o - | FileCheck %s
   2
   3 template <typename T>
   4 struct HasStaticInit {
   5 static const int index;
   6 };
   7 extern "C"
   8 int the_count = 0;
   9 template <typename T>
  10 const int HasStaticInit<T>::index = the_count++;
  11
  12 template <typename T> int func_tmpl1() { return HasStaticInit<T>::index; }
  13 template <typename T> int func_tmpl2() { return HasStaticInit<T>::index; }
  14 template <typename T> int func_tmpl3() { return HasStaticInit<T>::index; }
  15 void useit() {
  16   func_tmpl1<int>();
  17   func_tmpl2<int>();
  18   func_tmpl3<int>();
  19 }
  20
  21 // Throw in a final explicit instantiation to see that it doesn't screw things
  22 // up.
  23 template struct HasStaticInit<int>;
  24
  25 // There should only be one entry, not 3.
  26 // CHECK: @llvm.global_ctors = appending global [1 x { i32, ptr, ptr }]
  27
  28 // There should only be one update to @the_count.
  29 // CHECK-NOT: store i32 %{{.*}}, ptr @the_count
  30 // CHECK: store i32 %{{.*}}, ptr @the_count
  31 // CHECK-NOT: store i32 %{{.*}}, ptr @the_count