1 files changed, 24 insertions, 2 deletions
diff --git a/contrib/llvm-project/clang/lib/Sema/SemaOverload.cpp b/contrib/llvm-project/clang/lib/Sema/SemaOverload.cpp
index c226ed625479..d72cc33ed0f5 100644
--- a/contrib/llvm-project/clang/lib/Sema/SemaOverload.cpp
+++ b/contrib/llvm-project/clang/lib/Sema/SemaOverload.cpp
@@ -63,8 +63,9 @@ static ExprResult CreateFunctionRefExpr(
   // being used.
   if (FoundDecl != Fn && S.DiagnoseUseOfDecl(Fn, Loc))
     return ExprError();
-  DeclRefExpr *DRE = new (S.Context)
-      DeclRefExpr(S.Context, Fn, false, Fn->getType(), VK_LValue, Loc, LocInfo);
+  DeclRefExpr *DRE =
+      DeclRefExpr::Create(S.Context, Fn->getQualifierLoc(), SourceLocation(),
+                          Fn, false, Loc, Fn->getType(), VK_LValue, FoundDecl);
   if (HadMultipleCandidates)
     DRE->setHadMultipleCandidates(true);
 
@@ -6400,6 +6401,27 @@ void Sema::AddOverloadCandidate(
     return;
   }
 
+  // Functions with internal linkage are only viable in the same module unit.
+  if (auto *MF = Function->getOwningModule()) {
+    if (getLangOpts().CPlusPlusModules && !MF->isModuleMapModule() &&
+        !isModuleUnitOfCurrentTU(MF)) {
+      /// FIXME: Currently, the semantics of linkage in clang is slightly
+      /// different from the semantics in C++ spec. In C++ spec, only names
+      /// have linkage. So that all entities of the same should share one
+      /// linkage. But in clang, different entities of the same could have
+      /// different linkage.
+      NamedDecl *ND = Function;
+      if (auto *SpecInfo = Function->getTemplateSpecializationInfo())
+        ND = SpecInfo->getTemplate();
+      
+      if (ND->getFormalLinkage() == Linkage::InternalLinkage) {
+        Candidate.Viable = false;
+        Candidate.FailureKind = ovl_fail_module_mismatched;
+        return;
+      }
+    }
+  }
+
   if (Function->isMultiVersion() && Function->hasAttr<TargetAttr>() &&
       !Function->getAttr<TargetAttr>()->isDefaultVersion()) {
     Candidate.Viable = false;