Vendor import of clang trunk r256945:

https://llvm.org/svn/llvm-project/cfe/trunk@256945

1 files changed, 20 insertions, 12 deletions

diff --git a/lib/Sema/SemaTemplateDeduction.cpp b/lib/Sema/SemaTemplateDeduction.cpp
index de04c8a..cd54920 100644
--- a/lib/Sema/SemaTemplateDeduction.cpp
+++ b/lib/Sema/SemaTemplateDeduction.cpp
@@ -2954,8 +2954,12 @@ Sema::FinishTemplateArgumentDeduction(FunctionTemplateDecl *FunctionTemplate,
         continue;
       
       QualType DeducedA = Specialization->getParamDecl(ParamIdx)->getType();
-      if (CheckOriginalCallArgDeduction(*this, OriginalArg, DeducedA))
-        return Sema::TDK_SubstitutionFailure;
+      if (CheckOriginalCallArgDeduction(*this, OriginalArg, DeducedA)) {
+        Info.FirstArg = TemplateArgument(DeducedA);
+        Info.SecondArg = TemplateArgument(OriginalArg.OriginalArgType);
+        Info.CallArgIndex = OriginalArg.ArgIdx;
+        return TDK_DeducedMismatch;
+      }
     }
   }
   
@@ -4887,19 +4891,23 @@ MarkUsedTemplateParameters(ASTContext &Ctx, QualType T,
     break;
 
   case Type::DependentTemplateSpecialization: {
+    // C++14 [temp.deduct.type]p5:
+    //   The non-deduced contexts are:
+    //     -- The nested-name-specifier of a type that was specified using a
+    //        qualified-id
+    //
+    // C++14 [temp.deduct.type]p6:
+    //   When a type name is specified in a way that includes a non-deduced
+    //   context, all of the types that comprise that type name are also
+    //   non-deduced.
+    if (OnlyDeduced)
+      break;
+
     const DependentTemplateSpecializationType *Spec
       = cast<DependentTemplateSpecializationType>(T);
-    if (!OnlyDeduced)
-      MarkUsedTemplateParameters(Ctx, Spec->getQualifier(),
-                                 OnlyDeduced, Depth, Used);
 
-    // C++0x [temp.deduct.type]p9:
-    //   If the template argument list of P contains a pack expansion that is not
-    //   the last template argument, the entire template argument list is a
-    //   non-deduced context.
-    if (OnlyDeduced &&
-        hasPackExpansionBeforeEnd(Spec->getArgs(), Spec->getNumArgs()))
-      break;
+    MarkUsedTemplateParameters(Ctx, Spec->getQualifier(),
+                               OnlyDeduced, Depth, Used);
 
     for (unsigned I = 0, N = Spec->getNumArgs(); I != N; ++I)
       MarkUsedTemplateParameters(Ctx, Spec->getArg(I), OnlyDeduced, Depth,