Index: clang/include/clang/Sema/Sema.h
===================================================================
--- clang/include/clang/Sema/Sema.h
+++ clang/include/clang/Sema/Sema.h
@@ -9145,9 +9145,13 @@
                                                 const FunctionDecl *Callee);
 
   /// Determines whether Caller may invoke Callee, based on their CUDA
-  /// host/device attributes.  Returns true if the call is not allowed.
-  bool CheckCUDATarget(const FunctionDecl *Caller, const FunctionDecl *Callee) {
-    return IdentifyCUDAPreference(Caller, Callee) == CFP_Never;
+  /// host/device attributes.  Returns false if the call is not allowed.
+  ///
+  /// Note: Will return true for CFP_WrongSide calls.  These may appear in
+  /// semantically correct CUDA programs, but only if they're never codegen'ed.
+  bool IsAllowedCUDACall(const FunctionDecl *Caller,
+                         const FunctionDecl *Callee) {
+    return IdentifyCUDAPreference(Caller, Callee) != CFP_Never;
   }
 
   /// May add implicit CUDAHostAttr and CUDADeviceAttr attributes to FD,
Index: clang/lib/Sema/SemaExpr.cpp
===================================================================
--- clang/lib/Sema/SemaExpr.cpp
+++ clang/lib/Sema/SemaExpr.cpp
@@ -1749,7 +1749,7 @@
   if (getLangOpts().CUDA)
     if (const FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext))
       if (const FunctionDecl *Callee = dyn_cast<FunctionDecl>(D)) {
-        if (CheckCUDATarget(Caller, Callee)) {
+        if (!IsAllowedCUDACall(Caller, Callee)) {
           Diag(NameInfo.getLoc(), diag::err_ref_bad_target)
             << IdentifyCUDATarget(Callee) << D->getIdentifier()
             << IdentifyCUDATarget(Caller);
Index: clang/lib/Sema/SemaOverload.cpp
===================================================================
--- clang/lib/Sema/SemaOverload.cpp
+++ clang/lib/Sema/SemaOverload.cpp
@@ -5816,7 +5816,7 @@
       // case we may not yet know what the member's target is; the target is
       // inferred for the member automatically, based on the bases and fields of
       // the class.
-      if (!Caller->isImplicit() && CheckCUDATarget(Caller, Function)) {
+      if (!Caller->isImplicit() && !IsAllowedCUDACall(Caller, Function)) {
         Candidate.Viable = false;
         Candidate.FailureKind = ovl_fail_bad_target;
         return;
@@ -6193,7 +6193,7 @@
   // (CUDA B.1): Check for invalid calls between targets.
   if (getLangOpts().CUDA)
     if (const FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext))
-      if (CheckCUDATarget(Caller, Method)) {
+      if (!IsAllowedCUDACall(Caller, Method)) {
         Candidate.Viable = false;
         Candidate.FailureKind = ovl_fail_bad_target;
         return;
@@ -10468,7 +10468,7 @@
     if (FunctionDecl *FunDecl = dyn_cast<FunctionDecl>(Fn)) {
       if (S.getLangOpts().CUDA)
         if (FunctionDecl *Caller = dyn_cast<FunctionDecl>(S.CurContext))
-          if (!Caller->isImplicit() && S.CheckCUDATarget(Caller, FunDecl))
+          if (!Caller->isImplicit() && !S.IsAllowedCUDACall(Caller, FunDecl))
             return false;
 
       // If any candidate has a placeholder return type, trigger its deduction
@@ -12330,7 +12330,7 @@
   // (CUDA B.1): Check for invalid calls between targets.
   if (getLangOpts().CUDA) {
     if (const FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext)) {
-      if (CheckCUDATarget(Caller, Method)) {
+      if (!IsAllowedCUDACall(Caller, Method)) {
         Diag(MemExpr->getMemberLoc(), diag::err_ref_bad_target)
             << IdentifyCUDATarget(Method) << Method->getIdentifier()
             << IdentifyCUDATarget(Caller);