From: David Majnemer <david.majnemer@gmail.com>
Date: Mon, 19 Oct 2015 23:22:49 +0000 (+0000)
Subject: [MS ABI] Give linkonce_odr, instead of external_linkage, to certain kinds of static... 
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=44b224be95dddc719104e8e5856ab8a21d0b5eed;p=clang

[MS ABI] Give linkonce_odr, instead of external_linkage, to certain kinds of static data members

Out-of-line definitions of static data members which have an inline
initializer must get GVA_DiscardableODR linkage instead of
GVA_StrongExternal linkage.

MSVC 2013's behavior is different with respect to this and would cause
link errors if one TU provided a definition while another did not.
MSVC 2015 fixed this bug, making this OK.  Note that the 2015 behavior
is always compatible with 2013: it never produces a strong definition.

This essentially reverts r237787.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@250757 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index ffa8cbbf6c..848158877a 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -5035,8 +5035,8 @@ CharUnits ASTContext::getObjCEncodingTypeSize(QualType type) const {
 bool ASTContext::isMSStaticDataMemberInlineDefinition(const VarDecl *VD) const {
   return getTargetInfo().getCXXABI().isMicrosoft() &&
          VD->isStaticDataMember() &&
-         VD->getType()->isIntegralOrEnumerationType() && VD->isFirstDecl() &&
-         !VD->isOutOfLine() && VD->hasInit();
+         VD->getType()->isIntegralOrEnumerationType() &&
+         !VD->getFirstDecl()->isOutOfLine() && VD->getFirstDecl()->hasInit();
 }
 
 static inline 
diff --git a/test/CodeGenCXX/dllexport-members.cpp b/test/CodeGenCXX/dllexport-members.cpp
index da9e19cb15..76f692dbd3 100644
--- a/test/CodeGenCXX/dllexport-members.cpp
+++ b/test/CodeGenCXX/dllexport-members.cpp
@@ -110,10 +110,10 @@ public:
 
   // MSC-DAG: @"\01?StaticField@ExportMembers@@2HA"               = dllexport global i32 1, align 4
   // MSC-DAG: @"\01?StaticConstField@ExportMembers@@2HB"          = dllexport constant i32 1, align 4
-  // MSC-DAG: @"\01?StaticConstFieldEqualInit@ExportMembers@@2HB" = dllexport constant i32 1, comdat, align 4
-  // MSC-DAG: @"\01?StaticConstFieldBraceInit@ExportMembers@@2HB" = dllexport constant i32 1, comdat, align 4
+  // MSC-DAG: @"\01?StaticConstFieldEqualInit@ExportMembers@@2HB" = weak_odr dllexport constant i32 1, comdat, align 4
+  // MSC-DAG: @"\01?StaticConstFieldBraceInit@ExportMembers@@2HB" = weak_odr dllexport constant i32 1, comdat, align 4
   // MSC-DAG: @"\01?StaticConstFieldRefNotDef@ExportMembers@@2HB" = weak_odr dllexport constant i32 1, comdat, align 4
-  // MSC-DAG: @"\01?ConstexprField@ExportMembers@@2HB"            = dllexport constant i32 1, comdat, align 4
+  // MSC-DAG: @"\01?ConstexprField@ExportMembers@@2HB"            = weak_odr dllexport constant i32 1, comdat, align 4
   // GNU-DAG: @_ZN13ExportMembers11StaticFieldE                   = dllexport global i32 1, align 4
   // GNU-DAG: @_ZN13ExportMembers16StaticConstFieldE              = dllexport constant i32 1, align 4
   // GNU-DAG: @_ZN13ExportMembers25StaticConstFieldEqualInitE     = dllexport constant i32 1, align 4
@@ -236,10 +236,10 @@ public:
 
   // MSC-DAG: @"\01?StaticField@Nested@ExportMembers@@2HA"               = dllexport global i32 1, align 4
   // MSC-DAG: @"\01?StaticConstField@Nested@ExportMembers@@2HB"          = dllexport constant i32 1, align 4
-  // MSC-DAG: @"\01?StaticConstFieldEqualInit@Nested@ExportMembers@@2HB" = dllexport constant i32 1, comdat, align 4
-  // MSC-DAG: @"\01?StaticConstFieldBraceInit@Nested@ExportMembers@@2HB" = dllexport constant i32 1, comdat, align 4
+  // MSC-DAG: @"\01?StaticConstFieldEqualInit@Nested@ExportMembers@@2HB" = weak_odr dllexport constant i32 1, comdat, align 4
+  // MSC-DAG: @"\01?StaticConstFieldBraceInit@Nested@ExportMembers@@2HB" = weak_odr dllexport constant i32 1, comdat, align 4
   // MSC-DAG: @"\01?StaticConstFieldRefNotDef@Nested@ExportMembers@@2HB" = weak_odr dllexport constant i32 1, comdat, align 4
-  // MSC-DAG: @"\01?ConstexprField@Nested@ExportMembers@@2HB"            = dllexport constant i32 1, comdat, align 4
+  // MSC-DAG: @"\01?ConstexprField@Nested@ExportMembers@@2HB"            = weak_odr dllexport constant i32 1, comdat, align 4
   // GNU-DAG: @_ZN13ExportMembers6Nested11StaticFieldE                   = dllexport global i32 1, align 4
   // GNU-DAG: @_ZN13ExportMembers6Nested16StaticConstFieldE              = dllexport constant i32 1, align 4
   // GNU-DAG: @_ZN13ExportMembers6Nested25StaticConstFieldEqualInitE     = dllexport constant i32 1, align 4
diff --git a/test/CodeGenCXX/ms-integer-static-data-members.cpp b/test/CodeGenCXX/ms-integer-static-data-members.cpp
index 5e5b81d4a5..b2bfc92d26 100644
--- a/test/CodeGenCXX/ms-integer-static-data-members.cpp
+++ b/test/CodeGenCXX/ms-integer-static-data-members.cpp
@@ -42,10 +42,10 @@ const int S::OutOfLine_Def_Ref = 5;
 // CHECK-DAG: @"\01?Inline_NotDef_Ref@S@@2HB" = linkonce_odr constant i32 5, comdat, align 4
 
 // Inline initialization, real definiton, not referenced.
-// CHECK-DAG: @"\01?Inline_Def_NotRef@S@@2HB" = constant i32 5, align 4
+// CHECK-NOT: @"\01?Inline_Def_NotRef@S@@2HB" = constant i32 5, align 4
 
 // Inline initialization, real definiton, referenced.
-// CHECK-DAG: @"\01?Inline_Def_Ref@S@@2HB" = constant i32 5, comdat, align 4
+// CHECK-DAG: @"\01?Inline_Def_Ref@S@@2HB" = linkonce_odr constant i32 5, comdat, align 4
 
 // Out-of-line initialization.
 // CHECK-DAG: @"\01?OutOfLine_Def_NotRef@S@@2HB" = constant i32 5, align 4