CodeGen: static constexpr data members should have a linkonce_odr init

Classes can be defined in multiple translation units.  This means that
the static constexpr data members should have identical initializers in
all translation units.  Implement this by giving the reference temporary
linkonce_odr linkage.

llvm-svn: 229900

1 files changed, 25 insertions, 16 deletions

diff --git a/clang/test/CodeGenCXX/const-init-cxx11.cpp b/clang/test/CodeGenCXX/const-init-cxx11.cpp
index c61192a6f76..2ca76f6e760 100644
--- a/clang/test/CodeGenCXX/const-init-cxx11.cpp
+++ b/clang/test/CodeGenCXX/const-init-cxx11.cpp
@@ -226,30 +226,30 @@ namespace LiteralReference {
   };
 
   // This creates a non-const temporary and binds a reference to it.
-  // CHECK: @[[TEMP:.*]] = private global {{.*}} { i32 5 }, align 4
+  // CHECK: @[[TEMP:.*]] = internal global {{.*}} { i32 5 }, align 4
   // CHECK: @_ZN16LiteralReference3litE = constant {{.*}} @[[TEMP]], align 8
   const Lit &lit = Lit();
 
   // This creates a const temporary as part of the reference initialization.
-  // CHECK: @[[TEMP:.*]] = private constant {{.*}} { i32 5 }, align 4
+  // CHECK: @[[TEMP:.*]] = internal constant {{.*}} { i32 5 }, align 4
   // CHECK: @_ZN16LiteralReference4lit2E = constant {{.*}} @[[TEMP]], align 8
   const Lit &lit2 = {};
 
   struct A { int &&r1; const int &&r2; };
   struct B { A &&a1; const A &&a2; };
   B b = { { 0, 1 }, { 2, 3 } };
-  // CHECK: @[[TEMP0:.*]] = private global i32 0, align 4
-  // CHECK: @[[TEMP1:.*]] = private constant i32 1, align 4
-  // CHECK: @[[TEMPA1:.*]] = private global {{.*}} { i32* @[[TEMP0]], i32* @[[TEMP1]] }, align 8
-  // CHECK: @[[TEMP2:.*]] = private global i32 2, align 4
-  // CHECK: @[[TEMP3:.*]] = private constant i32 3, align 4
-  // CHECK: @[[TEMPA2:.*]] = private constant {{.*}} { i32* @[[TEMP2]], i32* @[[TEMP3]] }, align 8
+  // CHECK: @[[TEMP0:.*]] = internal global i32 0, align 4
+  // CHECK: @[[TEMP1:.*]] = internal constant i32 1, align 4
+  // CHECK: @[[TEMPA1:.*]] = internal global {{.*}} { i32* @[[TEMP0]], i32* @[[TEMP1]] }, align 8
+  // CHECK: @[[TEMP2:.*]] = internal global i32 2, align 4
+  // CHECK: @[[TEMP3:.*]] = internal constant i32 3, align 4
+  // CHECK: @[[TEMPA2:.*]] = internal constant {{.*}} { i32* @[[TEMP2]], i32* @[[TEMP3]] }, align 8
   // CHECK: @_ZN16LiteralReference1bE = global {{.*}} { {{.*}}* @[[TEMPA1]], {{.*}}* @[[TEMPA2]] }, align 8
 
   struct Subobj {
     int a, b, c;
   };
-  // CHECK: @[[TEMP:.*]] = private global {{.*}} { i32 1, i32 2, i32 3 }, align 4
+  // CHECK: @[[TEMP:.*]] = internal global {{.*}} { i32 1, i32 2, i32 3 }, align 4
   // CHECK: @_ZN16LiteralReference2soE = constant {{.*}} (i8* getelementptr {{.*}} @[[TEMP]]{{.*}}, i64 4)
   constexpr int &&so = Subobj{ 1, 2, 3 }.b;
 
@@ -258,11 +258,11 @@ namespace LiteralReference {
     constexpr Derived() : Dummy{200}, Subobj{4, 5, 6} {}
   };
   using ConstDerived = const Derived;
-  // CHECK: @[[TEMPCOMMA:.*]] = private constant {{.*}} { i32 200, i32 4, i32 5, i32 6 }
+  // CHECK: @[[TEMPCOMMA:.*]] = internal constant {{.*}} { i32 200, i32 4, i32 5, i32 6 }
   // CHECK: @_ZN16LiteralReference5commaE = constant {{.*}} getelementptr {{.*}} @[[TEMPCOMMA]]{{.*}}, i64 8)
   constexpr const int &comma = (1, (2, ConstDerived{}).b);
 
-  // CHECK: @[[TEMPDERIVED:.*]] = private global {{.*}} { i32 200, i32 4, i32 5, i32 6 }
+  // CHECK: @[[TEMPDERIVED:.*]] = internal global {{.*}} { i32 200, i32 4, i32 5, i32 6 }
   // CHECK: @_ZN16LiteralReference4baseE = constant {{.*}} getelementptr {{.*}} @[[TEMPDERIVED]]{{.*}}, i64 4)
   constexpr Subobj &&base = Derived{};
 
@@ -380,10 +380,10 @@ namespace PR13273 {
 namespace ArrayTemporary {
   struct A { const int (&x)[3]; };
   struct B { const A (&x)[2]; };
-  // CHECK: @[[A1:_ZGRN14ArrayTemporary1bE.*]] = private constant [3 x i32] [i32 1, i32 2, i32 3]
-  // CHECK: @[[A2:_ZGRN14ArrayTemporary1bE.*]] = private constant [3 x i32] [i32 4, i32 5, i32 6]
-  // CHECK: @[[ARR:_ZGRN14ArrayTemporary1bE.*]] = private constant [2 x {{.*}}] [{{.*}} { [3 x i32]* @[[A1]] }, {{.*}} { [3 x i32]* @[[A2]] }]
-  // CHECK: @[[B:_ZGRN14ArrayTemporary1bE.*]] = private global {{.*}} { [2 x {{.*}}]* @[[ARR]] }
+  // CHECK: @[[A1:_ZGRN14ArrayTemporary1bE.*]] = internal constant [3 x i32] [i32 1, i32 2, i32 3]
+  // CHECK: @[[A2:_ZGRN14ArrayTemporary1bE.*]] = internal constant [3 x i32] [i32 4, i32 5, i32 6]
+  // CHECK: @[[ARR:_ZGRN14ArrayTemporary1bE.*]] = internal constant [2 x {{.*}}] [{{.*}} { [3 x i32]* @[[A1]] }, {{.*}} { [3 x i32]* @[[A2]] }]
+  // CHECK: @[[B:_ZGRN14ArrayTemporary1bE.*]] = internal global {{.*}} { [2 x {{.*}}]* @[[ARR]] }
   // CHECK: @_ZN14ArrayTemporary1bE = constant {{.*}}* @[[B]]
   B &&b = { { { { 1, 2, 3 } }, { { 4, 5, 6 } } } };
 }
@@ -391,7 +391,7 @@ namespace ArrayTemporary {
 namespace UnemittedTemporaryDecl {
   constexpr int &&ref = 0;
   extern constexpr int &ref2 = ref;
-  // CHECK: @_ZGRN22UnemittedTemporaryDecl3refE_ = private global i32 0
+  // CHECK: @_ZGRN22UnemittedTemporaryDecl3refE_ = internal global i32 0
 
   // FIXME: This declaration should not be emitted -- it isn't odr-used.
   // CHECK: @_ZN22UnemittedTemporaryDecl3refE
@@ -596,6 +596,15 @@ namespace ClassTemplateWithHiddenStaticDataMember {
   const int &use = S<void>::a;
 }
 
+namespace ClassWithStaticConstexprDataMember {
+struct X {
+  static constexpr const char &p = 'c';
+};
+
+// CHECK: @_ZGRN34ClassWithStaticConstexprDataMember1X1pE_
+const char *f() { return &X::p; }
+}
+
 // VirtualMembers::TemplateClass::templateMethod() must be defined in this TU,
 // not just declared.
 // CHECK: define linkonce_odr void @_ZN14VirtualMembers13TemplateClassIiE14templateMethodEv(%"struct.VirtualMembers::TemplateClass"* %this)