Mark VTables and RTTI data linkonce_odr instead of weak_odr, with the exception of explicit template instantiations, which have to be weak_odr.

This fixes PR6996.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@124089 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGRTTI.cpp b/lib/CodeGen/CGRTTI.cpp
index 9f3571e..6e57f90 100644
--- a/lib/CodeGen/CGRTTI.cpp
+++ b/lib/CodeGen/CGRTTI.cpp
@@ -355,10 +355,10 @@
         return CodeGenModule::getVTableLinkage(RD);
     }
 
-    return llvm::GlobalValue::WeakODRLinkage;
+    return llvm::GlobalValue::LinkOnceODRLinkage;
   }
 
-  return llvm::GlobalValue::WeakODRLinkage;
+  return llvm::GlobalValue::LinkOnceODRLinkage;
 }
 
 // CanUseSingleInheritance - Return whether the given record decl has a "single, 
@@ -640,7 +640,7 @@
                           /*ForRTTI*/ true, /*ForDefinition*/ true);
   else if (Hidden || 
            (CGM.getCodeGenOpts().HiddenWeakVTables &&
-            Linkage == llvm::GlobalValue::WeakODRLinkage)) {
+            Linkage == llvm::GlobalValue::LinkOnceODRLinkage)) {
     GV->setVisibility(llvm::GlobalValue::HiddenVisibility);
   }
   GV->setUnnamedAddr(true);
diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index 631c335..ae61661 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -210,7 +210,7 @@
   // in CGVTables.cpp.
 
   // Preconditions.
-  if (GV->getLinkage() != llvm::GlobalVariable::WeakODRLinkage ||
+  if (GV->getLinkage() != llvm::GlobalVariable::LinkOnceODRLinkage ||
       GV->getVisibility() != llvm::GlobalVariable::DefaultVisibility)
     return;
 
@@ -1053,19 +1053,21 @@
       case TSK_Undeclared:
       case TSK_ExplicitSpecialization:
         if (KeyFunction->isInlined())
-          return llvm::GlobalVariable::WeakODRLinkage;
+          return llvm::GlobalVariable::LinkOnceODRLinkage;
         
         return llvm::GlobalVariable::ExternalLinkage;
         
       case TSK_ImplicitInstantiation:
+        return llvm::GlobalVariable::LinkOnceODRLinkage;
+
       case TSK_ExplicitInstantiationDefinition:
         return llvm::GlobalVariable::WeakODRLinkage;
-        
+  
       case TSK_ExplicitInstantiationDeclaration:
         // FIXME: Use available_externally linkage. However, this currently
         // breaks LLVM's build due to undefined symbols.
         //      return llvm::GlobalVariable::AvailableExternallyLinkage;
-        return llvm::GlobalVariable::WeakODRLinkage;
+        return llvm::GlobalVariable::LinkOnceODRLinkage;
     }
   }
   
@@ -1073,6 +1075,8 @@
   case TSK_Undeclared:
   case TSK_ExplicitSpecialization:
   case TSK_ImplicitInstantiation:
+    return llvm::GlobalVariable::LinkOnceODRLinkage;
+
   case TSK_ExplicitInstantiationDefinition:
     return llvm::GlobalVariable::WeakODRLinkage;
     
@@ -1080,11 +1084,11 @@
     // FIXME: Use available_externally linkage. However, this currently
     // breaks LLVM's build due to undefined symbols.
     //   return llvm::GlobalVariable::AvailableExternallyLinkage;
-    return llvm::GlobalVariable::WeakODRLinkage;
+    return llvm::GlobalVariable::LinkOnceODRLinkage;
   }
   
   // Silence GCC warning.
-  return llvm::GlobalVariable::WeakODRLinkage;
+  return llvm::GlobalVariable::LinkOnceODRLinkage;
 }
 
 CharUnits CodeGenModule::GetTargetTypeStoreSize(const llvm::Type *Ty) const {