3 files changed, 21 insertions, 7 deletions
diff --git a/clang/lib/Sema/SemaTemplateInstantiate.cpp b/clang/lib/Sema/SemaTemplateInstantiate.cpp
index 0e4dfcb14cb..1adf594c1ef 100644
--- a/clang/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiate.cpp
@@ -627,7 +627,7 @@ bool TemplateInstantiator::AlreadyTransformed(QualType T) {
   if (T.isNull())
     return true;
   
-  if (T->isDependentType())
+  if (T->isDependentType() || T->isVariablyModifiedType())
     return false;
   
   getSema().MarkDeclarationsReferencedInType(Loc, T);
@@ -942,7 +942,8 @@ TypeSourceInfo *Sema::SubstType(TypeSourceInfo *T,
          "Cannot perform an instantiation without some context on the "
          "instantiation stack");
   
-  if (!T->getType()->isDependentType())
+  if (!T->getType()->isDependentType() && 
+      !T->getType()->isVariablyModifiedType())
     return T;
 
   TemplateInstantiator Instantiator(*this, Args, Loc, Entity);
@@ -957,8 +958,9 @@ QualType Sema::SubstType(QualType T,
          "Cannot perform an instantiation without some context on the "
          "instantiation stack");
 
-  // If T is not a dependent type, there is nothing to do.
-  if (!T->isDependentType())
+  // If T is not a dependent type or a variably-modified type, there
+  // is nothing to do.
+  if (!T->isDependentType() && !T->isVariablyModifiedType())
     return T;
 
   TemplateInstantiator Instantiator(*this, TemplateArgs, Loc, Entity);
@@ -966,7 +968,7 @@ QualType Sema::SubstType(QualType T,
 }
 
 static bool NeedsInstantiationAsFunctionType(TypeSourceInfo *T) {
-  if (T->getType()->isDependentType())
+  if (T->getType()->isDependentType() || T->getType()->isVariablyModifiedType())
     return true;
 
   TypeLoc TL = T->getTypeLoc();
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 10d2bb119d3..834b86da9a0 100644
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -184,7 +184,8 @@ TemplateDeclInstantiator::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
 Decl *TemplateDeclInstantiator::VisitTypedefDecl(TypedefDecl *D) {
   bool Invalid = false;
   TypeSourceInfo *DI = D->getTypeSourceInfo();
-  if (DI->getType()->isDependentType()) {
+  if (DI->getType()->isDependentType() ||
+      DI->getType()->isVariablyModifiedType()) {
     DI = SemaRef.SubstType(DI, TemplateArgs,
                            D->getLocation(), D->getDeclName());
     if (!DI) {
@@ -438,7 +439,8 @@ Decl *TemplateDeclInstantiator::VisitVarDecl(VarDecl *D) {
 Decl *TemplateDeclInstantiator::VisitFieldDecl(FieldDecl *D) {
   bool Invalid = false;
   TypeSourceInfo *DI = D->getTypeSourceInfo();
-  if (DI->getType()->isDependentType())  {
+  if (DI->getType()->isDependentType() ||
+      DI->getType()->isVariablyModifiedType())  {
     DI = SemaRef.SubstType(DI, TemplateArgs,
                            D->getLocation(), D->getDeclName());
     if (!DI) {
diff --git a/clang/test/SemaCXX/c99-variable-length-array.cpp b/clang/test/SemaCXX/c99-variable-length-array.cpp
index 8a9bcb38cbf..8267701880d 100644
--- a/clang/test/SemaCXX/c99-variable-length-array.cpp
+++ b/clang/test/SemaCXX/c99-variable-length-array.cpp
@@ -90,3 +90,13 @@ namespace PR7206 {
     struct edge_info edgeInfo[x]; // expected-warning{{variable length arrays are a C99 feature, accepted as an extension}}
   }
 }
+
+namespace rdar8020206 {
+  template<typename T>
+  void f(int i) {
+    const unsigned value = i;
+    int array[value * i]; // expected-warning 2{{variable length arrays are a C99 feature, accepted as an extension}}
+  }
+
+  template void f<int>(int); // expected-note{{instantiation of}}
+}