3 files changed, 19 insertions, 7 deletions

diff --git a/lib/Sema/SemaLookup.cpp b/lib/Sema/SemaLookup.cpp
index 38a7b8c127cc..e2cb2c8169ce 100644
--- a/lib/Sema/SemaLookup.cpp
+++ b/lib/Sema/SemaLookup.cpp
@@ -2831,6 +2831,9 @@ Sema::SpecialMemberOverloadResult *Sema::LookupSpecialMember(CXXRecordDecl *RD,
     assert((SM != CXXDefaultConstructor && SM != CXXDestructor) &&
            "parameter-less special members can't have qualified arguments");
 
+  // FIXME: Get the caller to pass in a location for the lookup.
+  SourceLocation LookupLoc = RD->getLocation();
+
   llvm::FoldingSetNodeID ID;
   ID.AddPointer(RD);
   ID.AddInteger(SM);
@@ -2912,7 +2915,7 @@ Sema::SpecialMemberOverloadResult *Sema::LookupSpecialMember(CXXRecordDecl *RD,
       VK = VK_RValue;
   }
 
-  OpaqueValueExpr FakeArg(SourceLocation(), ArgType, VK);
+  OpaqueValueExpr FakeArg(LookupLoc, ArgType, VK);
 
   if (SM != CXXDefaultConstructor) {
     NumArgs = 1;
@@ -2926,13 +2929,13 @@ Sema::SpecialMemberOverloadResult *Sema::LookupSpecialMember(CXXRecordDecl *RD,
   if (VolatileThis)
     ThisTy.addVolatile();
   Expr::Classification Classification =
-    OpaqueValueExpr(SourceLocation(), ThisTy,
+    OpaqueValueExpr(LookupLoc, ThisTy,
                     RValueThis ? VK_RValue : VK_LValue).Classify(Context);
 
   // Now we perform lookup on the name we computed earlier and do overload
   // resolution. Lookup is only performed directly into the class since there
   // will always be a (possibly implicit) declaration to shadow any others.
-  OverloadCandidateSet OCS(RD->getLocation(), OverloadCandidateSet::CSK_Normal);
+  OverloadCandidateSet OCS(LookupLoc, OverloadCandidateSet::CSK_Normal);
   DeclContext::lookup_result R = RD->lookup(Name);
 
   if (R.empty()) {
@@ -2987,7 +2990,7 @@ Sema::SpecialMemberOverloadResult *Sema::LookupSpecialMember(CXXRecordDecl *RD,
   }
 
   OverloadCandidateSet::iterator Best;
-  switch (OCS.BestViableFunction(*this, SourceLocation(), Best)) {
+  switch (OCS.BestViableFunction(*this, LookupLoc, Best)) {
     case OR_Success:
       Result->setMethod(cast<CXXMethodDecl>(Best->Function));
       Result->setKind(SpecialMemberOverloadResult::Success);
diff --git a/lib/Sema/SemaStmt.cpp b/lib/Sema/SemaStmt.cpp
index a8832e9a1c54..390e1b52c8ed 100644
--- a/lib/Sema/SemaStmt.cpp
+++ b/lib/Sema/SemaStmt.cpp
@@ -2743,15 +2743,17 @@ bool Sema::isCopyElisionCandidate(QualType ReturnType, const VarDecl *VD,
   // ...automatic...
   if (!VD->hasLocalStorage()) return false;
 
+  // Return false if VD is a __block variable. We don't want to implicitly move
+  // out of a __block variable during a return because we cannot assume the
+  // variable will no longer be used.
+  if (VD->hasAttr<BlocksAttr>()) return false;
+
   if (AllowParamOrMoveConstructible)
     return true;
 
   // ...non-volatile...
   if (VD->getType().isVolatileQualified()) return false;
 
-  // __block variables can't be allocated in a way that permits NRVO.
-  if (VD->hasAttr<BlocksAttr>()) return false;
-
   // Variables with higher required alignment than their type's ABI
   // alignment cannot use NRVO.
   if (!VD->getType()->isDependentType() && VD->hasAttr<AlignedAttr>() &&
diff --git a/lib/Sema/SemaTemplateVariadic.cpp b/lib/Sema/SemaTemplateVariadic.cpp
index 54556b505ee0..725a3e425201 100644
--- a/lib/Sema/SemaTemplateVariadic.cpp
+++ b/lib/Sema/SemaTemplateVariadic.cpp
@@ -1014,6 +1014,11 @@ ExprResult Sema::ActOnCXXFoldExpr(SourceLocation LParenLoc, Expr *LHS,
   CheckFoldOperand(*this, LHS);
   CheckFoldOperand(*this, RHS);
 
+  auto DiscardOperands = [&] {
+    CorrectDelayedTyposInExpr(LHS);
+    CorrectDelayedTyposInExpr(RHS);
+  };
+
   // [expr.prim.fold]p3:
   //   In a binary fold, op1 and op2 shall be the same fold-operator, and
   //   either e1 shall contain an unexpanded parameter pack or e2 shall contain
@@ -1021,6 +1026,7 @@ ExprResult Sema::ActOnCXXFoldExpr(SourceLocation LParenLoc, Expr *LHS,
   if (LHS && RHS &&
       LHS->containsUnexpandedParameterPack() ==
           RHS->containsUnexpandedParameterPack()) {
+    DiscardOperands();
     return Diag(EllipsisLoc,
                 LHS->containsUnexpandedParameterPack()
                     ? diag::err_fold_expression_packs_both_sides
@@ -1034,6 +1040,7 @@ ExprResult Sema::ActOnCXXFoldExpr(SourceLocation LParenLoc, Expr *LHS,
   if (!LHS || !RHS) {
     Expr *Pack = LHS ? LHS : RHS;
     assert(Pack && "fold expression with neither LHS nor RHS");
+    DiscardOperands();
     if (!Pack->containsUnexpandedParameterPack())
       return Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
              << Pack->getSourceRange();