Index: lib/CodeGen/CodeGenModule.cpp
===================================================================
--- lib/CodeGen/CodeGenModule.cpp
+++ lib/CodeGen/CodeGenModule.cpp
@@ -3505,7 +3505,8 @@
               // Make a new global with the correct type, this is now guaranteed
               // to work.
               auto *NewGV = cast<llvm::GlobalVariable>(
-                  GetAddrOfGlobalVar(D, InitType, IsForDefinition));
+                  GetAddrOfGlobalVar(D, InitType, IsForDefinition)
+                      ->stripPointerCasts());
 
               // Erase the old global, since it is no longer used.
               GV->eraseFromParent();
@@ -3887,13 +3888,13 @@
   llvm::Constant *Entry =
       GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative));
 
-  // Strip off a bitcast if we got one back.
+  // Strip off pointer casts if we got them.
   if (auto *CE = dyn_cast<llvm::ConstantExpr>(Entry)) {
     assert(CE->getOpcode() == llvm::Instruction::BitCast ||
            CE->getOpcode() == llvm::Instruction::AddrSpaceCast ||
            // All zero index gep.
            CE->getOpcode() == llvm::Instruction::GetElementPtr);
-    Entry = CE->getOperand(0);
+    Entry = CE->stripPointerCasts();
   }
 
   // Entry is now either a Function or GlobalVariable.
@@ -3917,7 +3918,8 @@
 
     // Make a new global with the correct type, this is now guaranteed to work.
     GV = cast<llvm::GlobalVariable>(
-        GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative)));
+        GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative))
+            ->stripPointerCasts());
 
     // Replace all uses of the old global with the new global
     llvm::Constant *NewPtrForOldDecl =
Index: test/CodeGenCXX/cxx11-extern-constexpr.cpp
===================================================================
--- test/CodeGenCXX/cxx11-extern-constexpr.cpp
+++ test/CodeGenCXX/cxx11-extern-constexpr.cpp
@@ -1,10 +1,13 @@
-// RUN: %clang_cc1 -std=c++11 %s -emit-llvm -o - -triple x86_64-linux-gnu | FileCheck %s --check-prefix=CHECK --check-prefix=CXX11
-// RUN: %clang_cc1 -std=c++1z %s -emit-llvm -o - -triple x86_64-linux-gnu | FileCheck %s --check-prefix=CHECK --check-prefix=CXX17
+// RUN: %clang_cc1 -std=c++11 %s -emit-llvm -o - -triple x86_64-linux-gnu | FileCheck %s --check-prefixes=X86,CXX11X86
+// RUN: %clang_cc1 -std=c++1z %s -emit-llvm -o - -triple x86_64-linux-gnu | FileCheck %s --check-prefixes=X86,CXX17X86
+// RUN: %clang_cc1 -std=c++11 %s -emit-llvm -o - -triple amdgcn-amd-amdhsa | FileCheck %s --check-prefixes=AMD,CXX11AMD
+// RUN: %clang_cc1 -std=c++1z %s -emit-llvm -o - -triple amdgcn-amd-amdhsa | FileCheck %s --check-prefixes=AMD,CXX17AMD
 
 struct A {
   static const int Foo = 123;
 };
-// CHECK: @_ZN1A3FooE = constant i32 123, align 4
+// X86: @_ZN1A3FooE = constant i32 123, align 4
+// AMD: @_ZN1A3FooE = addrspace(4) constant i32 123, align 4
 const int *p = &A::Foo; // emit available_externally
 const int A::Foo;       // convert to full definition
 
@@ -16,7 +19,8 @@
   // Deferred initialization of the structure here requires changing
   // the type of the global variable: the initializer list does not include
   // the tail padding.
-  // CXX11: @_ZN9CreatePOD3podE = available_externally constant { i32, i8 } { i32 42, i8 43 },
+  // CXX11X86: @_ZN9CreatePOD3podE = available_externally constant { i32, i8 } { i32 42, i8 43 },
+  // CXX11AMD: @_ZN9CreatePOD3podE = available_externally addrspace(1) constant { i32, i8 } { i32 42, i8 43 },
   static constexpr PODWithInit pod{};
 };
 const int *p_pod = &CreatePOD::pod.g;
@@ -30,29 +34,40 @@
 };
 
 struct Foo {
-  // CXX11: @_ZN3Foo21ConstexprStaticMemberE = available_externally constant i32 42,
-  // CXX17: @_ZN3Foo21ConstexprStaticMemberE = linkonce_odr constant i32 42,
+  // CXX11X86: @_ZN3Foo21ConstexprStaticMemberE = available_externally constant i32 42,
+  // CXX17X86: @_ZN3Foo21ConstexprStaticMemberE = linkonce_odr constant i32 42,
+  // CXX11AMD: @_ZN3Foo21ConstexprStaticMemberE = available_externally addrspace(4) constant i32 42,
+  // CXX17AMD: @_ZN3Foo21ConstexprStaticMemberE = linkonce_odr addrspace(4) constant i32 42,
   static constexpr int ConstexprStaticMember = 42;
-  // CHECK: @_ZN3Foo17ConstStaticMemberE = available_externally constant i32 43,
+  // X86: @_ZN3Foo17ConstStaticMemberE = available_externally constant i32 43,
+  // AMD: @_ZN3Foo17ConstStaticMemberE = available_externally addrspace(4) constant i32 43,
   static const int ConstStaticMember = 43;
 
-  // CXX11: @_ZN3Foo23ConstStaticStructMemberE = available_externally constant %struct.Bar { i32 44 },
-  // CXX17: @_ZN3Foo23ConstStaticStructMemberE = linkonce_odr constant %struct.Bar { i32 44 },
+  // CXX11X86: @_ZN3Foo23ConstStaticStructMemberE = available_externally constant %struct.Bar { i32 44 },
+  // CXX17X86: @_ZN3Foo23ConstStaticStructMemberE = linkonce_odr constant %struct.Bar { i32 44 },
+  // CXX11AMD: @_ZN3Foo23ConstStaticStructMemberE = available_externally addrspace(1) constant %struct.Bar { i32 44 },
+  // CXX17AMD: @_ZN3Foo23ConstStaticStructMemberE = linkonce_odr addrspace(1) constant %struct.Bar { i32 44 },
   static constexpr Bar ConstStaticStructMember = {44};
 
-  // CXX11: @_ZN3Foo34ConstexprStaticMutableStructMemberE = external global %struct.MutableBar,
-  // CXX17: @_ZN3Foo34ConstexprStaticMutableStructMemberE = linkonce_odr global %struct.MutableBar { i32 45 },
+  // CXX11X86: @_ZN3Foo34ConstexprStaticMutableStructMemberE = external global %struct.MutableBar,
+  // CXX17X86: @_ZN3Foo34ConstexprStaticMutableStructMemberE = linkonce_odr global %struct.MutableBar { i32 45 },
+  // CXX11AMD: @_ZN3Foo34ConstexprStaticMutableStructMemberE = external addrspace(1) global %struct.MutableBar,
+  // CXX17AMD: @_ZN3Foo34ConstexprStaticMutableStructMemberE = linkonce_odr addrspace(1) global %struct.MutableBar { i32 45 },
   static constexpr MutableBar ConstexprStaticMutableStructMember = {45};
 };
-// CHECK: @_ZL15ConstStaticexpr = internal constant i32 46,
+// X86: @_ZL15ConstStaticexpr = internal constant i32 46,
+// AMD: @_ZL15ConstStaticexpr = internal addrspace(4) constant i32 46,
 static constexpr int ConstStaticexpr = 46;
-// CHECK: @_ZL9ConstExpr = internal constant i32 46, align 4
+// X86: @_ZL9ConstExpr = internal constant i32 46, align 4
+// AMD: @_ZL9ConstExpr = internal addrspace(4) constant i32 46, align 4
 static const int ConstExpr = 46;
 
-// CHECK: @_ZL21ConstexprStaticStruct = internal constant %struct.Bar { i32 47 },
+// X86: @_ZL21ConstexprStaticStruct = internal constant %struct.Bar { i32 47 },
+// AMD: @_ZL21ConstexprStaticStruct = internal addrspace(1) constant %struct.Bar { i32 47 },
 static constexpr Bar ConstexprStaticStruct = {47};
 
-// CHECK: @_ZL28ConstexprStaticMutableStruct = internal global %struct.MutableBar { i32 48 },
+// X86: @_ZL28ConstexprStaticMutableStruct = internal global %struct.MutableBar { i32 48 },
+// AMD: @_ZL28ConstexprStaticMutableStruct = internal addrspace(1) global %struct.MutableBar { i32 48 },
 static constexpr MutableBar ConstexprStaticMutableStruct = {48};
 
 void use(const int &);