[Sema] Diagnose addr space mismatch while constructing objects

If we construct an object in some arbitrary non-default addr space
it should fail unless either:
- There is an implicit conversion from the address space to default
/generic address space.
- There is a matching ctor qualified with an address space that is
either exactly matching or convertible to the address space of an
object.

Differential Revision: https://reviews.llvm.org/D62156



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@363944 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 24 insertions, 2 deletions

diff --git a/lib/Sema/SemaOverload.cpp b/lib/Sema/SemaOverload.cpp
index 70bb757607..11595fac2c 100644
--- a/lib/Sema/SemaOverload.cpp
+++ b/lib/Sema/SemaOverload.cpp
@@ -6101,6 +6101,15 @@ void Sema::AddOverloadCandidate(
         return;
       }
     }
+
+    // Check that the constructor is capable of constructing an object in the
+    // destination address space.
+    if (!Qualifiers::isAddressSpaceSupersetOf(
+            Constructor->getMethodQualifiers().getAddressSpace(),
+            CandidateSet.getDestAS())) {
+      Candidate.Viable = false;
+      Candidate.FailureKind = ovl_fail_object_addrspace_mismatch;
+    }
   }
 
   unsigned NumParams = Proto->getNumParams();
@@ -10392,9 +10401,12 @@ static void DiagnoseOpenCLExtensionDisabled(Sema &S, OverloadCandidate *Cand) {
 /// It would be great to be able to express per-candidate problems
 /// more richly for those diagnostic clients that cared, but we'd
 /// still have to be just as careful with the default diagnostics.
+/// \param CtorDestAS Addr space of object being constructed (for ctor
+/// candidates only).
 static void NoteFunctionCandidate(Sema &S, OverloadCandidate *Cand,
                                   unsigned NumArgs,
-                                  bool TakingCandidateAddress) {
+                                  bool TakingCandidateAddress,
+                                  LangAS CtorDestAS = LangAS::Default) {
   FunctionDecl *Fn = Cand->Function;
 
   // Note deleted candidates, but only if they're viable.
@@ -10432,6 +10444,16 @@ static void NoteFunctionCandidate(Sema &S, OverloadCandidate *Cand,
     return;
   }
 
+  case ovl_fail_object_addrspace_mismatch: {
+    Qualifiers QualsForPrinting;
+    QualsForPrinting.setAddressSpace(CtorDestAS);
+    S.Diag(Fn->getLocation(),
+           diag::note_ovl_candidate_illegal_constructor_adrspace_mismatch)
+        << QualsForPrinting;
+    MaybeEmitInheritedConstructorNote(S, Cand->FoundDecl);
+    return;
+  }
+
   case ovl_fail_trivial_conversion:
   case ovl_fail_bad_final_conversion:
   case ovl_fail_final_conversion_not_exact:
@@ -10862,7 +10884,7 @@ void OverloadCandidateSet::NoteCandidates(Sema &S, ArrayRef<Expr *> Args,
 
     if (Cand->Function)
       NoteFunctionCandidate(S, Cand, Args.size(),
-                            /*TakingCandidateAddress=*/false);
+                            /*TakingCandidateAddress=*/false, DestAS);
     else if (Cand->IsSurrogate)
       NoteSurrogateCandidate(S, Cand);
     else {