text: // RUN: %clang_cc1 -triple x86_64-linux-gnu -std=c++17 -emit-llvm -DIMPORT=1 -fmodules %s -o - | FileCheck %s --check-prefixes=CHECK,CHECK-IMPORT,CHECK-NO-NS,CHECK-IMPORT-NO-NS --implicit-check-not=unused
  // RUN: %clang_cc1 -triple x86_64-linux-gnu -std=c++17 -emit-llvm -DIMPORT=1 -DNS -fmodules %s -o - | FileCheck %s --check-prefixes=CHECK,CHECK-IMPORT,CHECK-NS,CHECK-IMPORT-NS --implicit-check-not=unused
  // RUN: %clang_cc1 -triple x86_64-linux-gnu -std=c++17 -emit-llvm -DIMPORT=2 -fmodules %s -o - | FileCheck %s --check-prefixes=CHECK,CHECK-NO-NS --implicit-check-not=unused
  // RUN: %clang_cc1 -triple x86_64-linux-gnu -std=c++17 -emit-llvm -DIMPORT=2 -DNS -fmodules %s -o - | FileCheck %s --check-prefixes=CHECK,CHECK-NS --implicit-check-not=unused
  // RUN: %clang_cc1 -triple x86_64-linux-gnu -std=c++17 -emit-llvm -fmodules %s -o - | FileCheck %s --check-prefixes=CHECK,CHECK-NO-NS --implicit-check-not=unused
  // RUN: %clang_cc1 -triple x86_64-linux-gnu -std=c++17 -emit-llvm -DNS -fmodules %s -o - | FileCheck %s --check-prefixes=CHECK,CHECK-NS --implicit-check-not=unused
  
  // Check that we behave sensibly when importing a header containing strong and
  // weak, ordered and unordered global initializers.
  //
  // Our behavior is as follows:
  //
  //  -- for variables with one or more specific points of initialization
  //     (non-template variables, whether or not they are inline or thread_local),
  //     emit them if (and only if) a header containing a point of initialization
  //     is transitively #included / imported.
  //
  //  -- for variables with unordered initialization (any kind of templated
  //     variable -- excluding explicit specializations), emit them if any part
  //     of any module that triggers an instantiation is imported.
  //
  // The intent is to:
  //
  // 1) preserve order of initialization guarantees
  // 2) preserve the behavior of globals with ctors in headers, and specifically
  //    of std::ios_base::Init (do not run the iostreams initializer nor force
  //    linking in the iostreams portion of the static library unless <iostream>
  //    is included)
  // 3) behave conservatively-correctly with regard to unordered initializers: we
  //    might run them in cases where a traditional compilation would not, but
  //    will never fail to run them in cases where a traditional compilation
  //    would do so
  //
  // Perfect handling of unordered initializers would require tracking all
  // submodules containing points of instantiation, which is very hard when those
  // points of instantiation are within definitions that we skip because we
  // already have a (non-visible) definition for the entity:
  //
  // // a.h
  // template<typename> int v = f();
  // inline int get() { return v<int>; }
  //
  // // b.h
  // template<typename> int v = f();
  // inline int get() { return v<int>; }
  //
  // If a.h and b.h are built as a module, we will only have a point of
  // instantiation for v<int> in one of the two headers, because we will only
  // parse one of the two get() functions.
  
  #pragma clang module build m
  module m {
    module a {
      header "foo.h" { size 123 mtime 456789 }
    }
    module b {}
  }
  
  #pragma clang module contents
  #pragma clang module begin m.a
  inline int non_trivial() { return 3; }
  
  #ifdef NS
  namespace ns {
  #endif
  
  int a = non_trivial();
  inline int b = non_trivial();
  thread_local int c = non_trivial();
  inline thread_local int d = non_trivial();
  
  template<typename U> int e = non_trivial();
  template<typename U> inline int f = non_trivial();
  template<typename U> thread_local int g = non_trivial();
  template<typename U> inline thread_local int h = non_trivial();
  
  inline int unused = 123; // should not be emitted
  
  template<typename T> struct X {
    static int a;
    static inline int b = non_trivial();
    static thread_local int c;
    static inline thread_local int d = non_trivial();
  
    template<typename U> static int e;
    template<typename U> static inline int f = non_trivial();
    template<typename U> static thread_local int g;
    template<typename U> static inline thread_local int h = non_trivial();
  
    static inline int unused = 123; // should not be emitted
  };
  
  template<typename T> int X<T>::a = non_trivial();
  template<typename T> thread_local int X<T>::c = non_trivial();
  template<typename T> template<typename U> int X<T>::e = non_trivial();
  template<typename T> template<typename U> thread_local int X<T>::g = non_trivial();
  
  inline void use(bool b, ...) {
    if (b) return;
    use(true, e<int>, f<int>, g<int>, h<int>,
        X<int>::a, X<int>::b, X<int>::c, X<int>::d,
        X<int>::e<int>, X<int>::f<int>, X<int>::g<int>, X<int>::h<int>);
  }
  
  #ifdef NS
  }
  #endif
  
  #pragma clang module end
  #pragma clang module endbuild
  
  #if IMPORT == 1
  // Import the module and the m.a submodule; runs the ordered initializers and
  // the unordered initializers.
  #pragma clang module import m.a
  #elif IMPORT == 2
  // Import the module but not the m.a submodule; runs only the unordered
  // initializers.
  #pragma clang module import m.b
  #else
  // Load the module but do not import any submodules; runs only the unordered
  // initializers. FIXME: Should this skip all of them?
  #pragma clang module load m
  #endif
  
  // CHECK-IMPORT-NO-NS-DAG: @[[A:a]] ={{.*}} global i32 0, align 4
  // CHECK-IMPORT-NO-NS-DAG: @[[B:b]] = linkonce_odr global i32 0, comdat, align 4
  // CHECK-IMPORT-NO-NS-DAG: @[[C:c]] ={{.*}} thread_local global i32 0, align 4
  // CHECK-IMPORT-NO-NS-DAG: @[[D:d]] = linkonce_odr thread_local global i32 0, comdat, align 4
  // CHECK-NO-NS-DAG: @[[E:_Z1eIiE]] = linkonce_odr global i32 0, comdat, align 4
  // CHECK-NO-NS-DAG: @[[F:_Z1fIiE]] = linkonce_odr global i32 0, comdat, align 4
  // CHECK-NO-NS-DAG: @[[G:_Z1gIiE]] = linkonce_odr thread_local global i32 0, comdat, align 4
  // CHECK-NO-NS-DAG: @[[H:_Z1hIiE]] = linkonce_odr thread_local global i32 0, comdat, align 4
  
  // CHECK-IMPORT-NS-DAG: @[[A:_ZN2ns1aE]] ={{.*}} global i32 0, align 4
  // CHECK-IMPORT-NS-DAG: @[[B:_ZN2ns1bE]] = linkonce_odr global i32 0, comdat, align 4
  // CHECK-IMPORT-NS-DAG: @[[BG:_ZGVN2ns1bE]] = linkonce_odr global i64 0, comdat($[[B]]), align 8
  // CHECK-IMPORT-NS-DAG: @[[C:_ZN2ns1cE]] ={{.*}} thread_local global i32 0, align 4
  // CHECK-IMPORT-NS-DAG: @[[D:_ZN2ns1dE]] = linkonce_odr thread_local global i32 0, comdat, align 4
  // CHECK-IMPORT-NS-DAG: @[[DG:_ZGVN2ns1dE]] = linkonce_odr thread_local global i64 0, comdat($[[D]]), align 8
  // CHECK-NS-DAG: @[[E:_ZN2ns1eIiEE]] = linkonce_odr global i32 0, comdat, align 4
  // CHECK-NS-DAG: @[[F:_ZN2ns1fIiEE]] = linkonce_odr global i32 0, comdat, align 4
  // CHECK-NS-DAG: @[[G:_ZN2ns1gIiEE]] = linkonce_odr thread_local global i32 0, comdat, align 4
  // CHECK-NS-DAG: @[[H:_ZN2ns1hIiEE]] = linkonce_odr thread_local global i32 0, comdat, align 4
  
  // CHECK-DAG: @[[XA:_ZN(2ns)?1XIiE1aE]] = linkonce_odr global i32 0, comdat, align 4
  // CHECK-DAG: @[[XB:_ZN(2ns)?1XIiE1bE]] = linkonce_odr global i32 0, comdat, align 4
  // CHECK-DAG: @[[XC:_ZN(2ns)?1XIiE1cE]] = linkonce_odr thread_local global i32 0, comdat, align 4
  // CHECK-DAG: @[[XD:_ZN(2ns)?1XIiE1dE]] = linkonce_odr thread_local global i32 0, comdat, align 4
  // CHECK-DAG: @[[XE:_ZN(2ns)?1XIiE1eIiEE]] = linkonce_odr global i32 0, comdat, align 4
  // CHECK-DAG: @[[XF:_ZN(2ns)?1XIiE1fIiEE]] = linkonce_odr global i32 0, comdat, align 4
  // CHECK-DAG: @[[XG:_ZN(2ns)?1XIiE1gIiEE]] = linkonce_odr thread_local global i32 0, comdat, align 4
  // CHECK-DAG: @[[XH:_ZN(2ns)?1XIiE1hIiEE]] = linkonce_odr thread_local global i32 0, comdat, align 4
  
  // It's OK if the order of the first 6 of these changes.
  // CHECK: @llvm.global_ctors = appending global
  // CHECK-SAME: @[[E_INIT:[^,]*]], {{[^@]*}} @[[E]]
  // CHECK-SAME: @[[F_INIT:[^,]*]], {{[^@]*}} @[[F]]
  // CHECK-SAME: @[[XA_INIT:[^,]*]], {{[^@]*}} @[[XA]]
  // CHECK-SAME: @[[XE_INIT:[^,]*]], {{[^@]*}} @[[XE]]
  // CHECK-SAME: @[[XF_INIT:[^,]*]], {{[^@]*}} @[[XF]]
  // CHECK-SAME: @[[XB_INIT:[^,]*]], {{[^@]*}} @[[XB]]
  // CHECK-IMPORT-SAME: @[[TU_INIT:[^,]*]], i8* null }]
  
  // FIXME: Should this use __cxa_guard_acquire?
  // CHECK: define {{.*}} @[[E_INIT]]()
  // CHECK: load {{.*}} (i64* @_ZGV
  // CHECK: store {{.*}}, i32* @[[E]],
  
  // FIXME: Should this use __cxa_guard_acquire?
  // CHECK: define {{.*}} @[[F_INIT]]()
  // CHECK: load {{.*}} (i64* @_ZGV
  // CHECK: store {{.*}}, i32* @[[F]],
  
  // CHECK: define {{.*}} @[[G_INIT:__cxx_global.*]]()
  // CHECK: load {{.*}} (i64* @_ZGV
  // CHECK: store {{.*}}, i32* @[[G]],
  
  // CHECK: define {{.*}} @[[H_INIT:__cxx_global.*]]()
  // CHECK: load {{.*}} (i64* @_ZGV
  // CHECK: store {{.*}}, i32* @[[H]],
  
  // FIXME: Should this use __cxa_guard_acquire?
  // CHECK: define {{.*}} @[[XA_INIT]]()
  // CHECK: load {{.*}} (i64* @_ZGV
  // CHECK: store {{.*}}, i32* @[[XA]],
  
  // CHECK: define {{.*}} @[[XC_INIT:__cxx_global.*]]()
  // CHECK: load {{.*}} (i64* @_ZGV
  // CHECK: store {{.*}}, i32* @[[XC]],
  
  // FIXME: Should this use __cxa_guard_acquire?
  // CHECK: define {{.*}} @[[XE_INIT]]()
  // CHECK: load {{.*}} (i64* @_ZGV
  // CHECK: store {{.*}}, i32* @[[XE]],
  
  // CHECK: define {{.*}} @[[XG_INIT:__cxx_global.*]]()
  // CHECK: load {{.*}} (i64* @_ZGV
  // CHECK: store {{.*}}, i32* @[[XG]],
  
  // CHECK: define {{.*}} @[[XH_INIT:__cxx_global.*]]()
  // CHECK: load {{.*}} (i64* @_ZGV
  // CHECK: store {{.*}}, i32* @[[XH]],
  
  // FIXME: Should this use __cxa_guard_acquire?
  // CHECK: define {{.*}} @[[XF_INIT]]()
  // CHECK: load {{.*}} (i64* @_ZGV
  // CHECK: store {{.*}}, i32* @[[XF]],
  
  // CHECK: define {{.*}} @[[XD_INIT:__cxx_global.*]]()
  // CHECK: load {{.*}} (i64* @_ZGV
  // CHECK: store {{.*}}, i32* @[[XD]],
  
  // FIXME: Should this use __cxa_guard_acquire?
  // CHECK: define {{.*}} @[[XB_INIT]]()
  // CHECK: load {{.*}} (i64* @_ZGV
  // CHECK: store {{.*}}, i32* @[[XB]],
  
  // CHECK-IMPORT: define {{.*}} @[[A_INIT:__cxx_global.*]]()
  // CHECK-IMPORT: call noundef i32 @_Z11non_trivialv(
  // CHECK-IMPORT: store {{.*}}, i32* @[[A]],
  
  // CHECK-IMPORT: define {{.*}} @[[B_INIT:__cxx_global.*]]()
  // CHECK-IMPORT: call i32 @__cxa_guard_acquire(i64* @_ZGV
  // CHECK-IMPORT: store {{.*}}, i32* @[[B]],
  
  // CHECK-IMPORT: define {{.*}} @[[C_INIT:__cxx_global.*]]()
  // CHECK-IMPORT: call noundef i32 @_Z11non_trivialv(
  // CHECK-IMPORT: store {{.*}}, i32* @[[C]],
  
  // CHECK-IMPORT: define {{.*}} @[[D_INIT:__cxx_global.*]]()
  // CHECK-IMPORT: load {{.*}} (i64* @_ZGV
  // CHECK-IMPORT: store {{.*}}, i32* @[[D]],
  
  
  // CHECK-IMPORT: define {{.*}} @[[TU_INIT]]()
  // CHECK-IMPORT: call void @[[A_INIT]]()
  
  // CHECK-IMPORT: define {{.*}} @__tls_init()
  // CHECK-IMPORT: call void @[[C_INIT]]()
  // CHECK-IMPORT: call void @[[D_INIT]]()
  