From 58d59d4b68ffc5f9d77868720917effa21d096df Mon Sep 17 00:00:00 2001
From: Richard Smith <richard-llvm@metafoo.co.uk>
Date: Fri, 21 Oct 2016 23:01:55 +0000
Subject: [PATCH] Remove unnecessary distinction between Ref_Compatible and
 Ref_Compatible_With_Added_Qualification. We always treated these two values
 the same way.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@284895 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/clang/Sema/Sema.h |  8 +-------
 lib/Sema/SemaCast.cpp     |  2 +-
 lib/Sema/SemaInit.cpp     |  7 +++----
 lib/Sema/SemaOverload.cpp | 13 +++++--------
 4 files changed, 10 insertions(+), 20 deletions(-)

diff --git a/include/clang/Sema/Sema.h b/include/clang/Sema/Sema.h
index 37d814bfd8..be5a0bcd58 100644
--- a/include/clang/Sema/Sema.h
+++ b/include/clang/Sema/Sema.h
@@ -8992,13 +8992,7 @@ public:
     /// that their unqualified forms (T1 and T2) are either the same
     /// or T1 is a base class of T2.
     Ref_Related,
-    /// Ref_Compatible_With_Added_Qualification - The two types are
-    /// reference-compatible with added qualification, meaning that
-    /// they are reference-compatible and the qualifiers on T1 (cv1)
-    /// are greater than the qualifiers on T2 (cv2).
-    Ref_Compatible_With_Added_Qualification,
-    /// Ref_Compatible - The two types are reference-compatible and
-    /// have equivalent qualifiers (cv1 == cv2).
+    /// Ref_Compatible - The two types are reference-compatible.
     Ref_Compatible
   };
 
diff --git a/lib/Sema/SemaCast.cpp b/lib/Sema/SemaCast.cpp
index e19020c6ad..43fdf59042 100644
--- a/lib/Sema/SemaCast.cpp
+++ b/lib/Sema/SemaCast.cpp
@@ -1165,7 +1165,7 @@ TryLValueToRValueCast(Sema &Self, Expr *SrcExpr, QualType DestType,
                                         ToType, FromType,
                                         DerivedToBase, ObjCConversion,
                                         ObjCLifetimeConversion) 
-        < Sema::Ref_Compatible_With_Added_Qualification) {
+        != Sema::Ref_Compatible) {
     if (CStyle)
       return TC_NotApplicable;
     msg = diag::err_bad_lvalue_to_rvalue_cast;
diff --git a/lib/Sema/SemaInit.cpp b/lib/Sema/SemaInit.cpp
index c6a773cf8f..f5e38b4fbd 100644
--- a/lib/Sema/SemaInit.cpp
+++ b/lib/Sema/SemaInit.cpp
@@ -4263,7 +4263,7 @@ static void TryReferenceInitializationCore(Sema &S,
   bool T1Function = T1->isFunctionType();
   if (isLValueRef || T1Function) {
     if (InitCategory.isLValue() &&
-        (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification ||
+        (RefRelationship == Sema::Ref_Compatible ||
          (Kind.isCStyleOrFunctionalCast() &&
           RefRelationship == Sema::Ref_Related))) {
       //   - is an lvalue (but is not a bit-field), and "cv1 T1" is
@@ -4336,7 +4336,7 @@ static void TryReferenceInitializationCore(Sema &S,
   //        "cv1 T1" is reference-compatible with "cv2 T2"
   // Note: functions are handled below.
   if (!T1Function &&
-      (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification ||
+      (RefRelationship == Sema::Ref_Compatible ||
        (Kind.isCStyleOrFunctionalCast() &&
         RefRelationship == Sema::Ref_Related)) &&
       (InitCategory.isXValue() ||
@@ -4393,8 +4393,7 @@ static void TryReferenceInitializationCore(Sema &S,
       return;
     }
 
-    if ((RefRelationship == Sema::Ref_Compatible ||
-         RefRelationship == Sema::Ref_Compatible_With_Added_Qualification) &&
+    if (RefRelationship == Sema::Ref_Compatible &&
         isRValueRef && InitCategory.isLValue()) {
       Sequence.SetFailed(
         InitializationSequence::FK_RValueReferenceBindingToLValue);
diff --git a/lib/Sema/SemaOverload.cpp b/lib/Sema/SemaOverload.cpp
index 8d6c562dd0..a39ad58c4f 100644
--- a/lib/Sema/SemaOverload.cpp
+++ b/lib/Sema/SemaOverload.cpp
@@ -4220,10 +4220,8 @@ Sema::CompareReferenceRelationship(SourceLocation Loc,
   T1Quals.removeUnaligned();
   T2Quals.removeUnaligned();
 
-  if (T1Quals == T2Quals)
+  if (T1Quals.compatiblyIncludes(T2Quals))
     return Ref_Compatible;
-  else if (T1Quals.compatiblyIncludes(T2Quals))
-    return Ref_Compatible_With_Added_Qualification;
   else
     return Ref_Related;
 }
@@ -4401,8 +4399,7 @@ TryReferenceInit(Sema &S, Expr *Init, QualType DeclType,
     //        reference-compatible with "cv2 T2," or
     //
     // Per C++ [over.ics.ref]p4, we don't check the bit-field property here.
-    if (InitCategory.isLValue() &&
-        RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification) {
+    if (InitCategory.isLValue() && RefRelationship == Sema::Ref_Compatible) {
       // C++ [over.ics.ref]p1:
       //   When a parameter of reference type binds directly (8.5.3)
       //   to an argument expression, the implicit conversion sequence
@@ -4464,10 +4461,10 @@ TryReferenceInit(Sema &S, Expr *Init, QualType DeclType,
   //
   //            -- is an xvalue, class prvalue, array prvalue or function
   //               lvalue and "cv1 T1" is reference-compatible with "cv2 T2", or
-  if (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification &&
+  if (RefRelationship == Sema::Ref_Compatible &&
       (InitCategory.isXValue() ||
-      (InitCategory.isPRValue() && (T2->isRecordType() || T2->isArrayType())) ||
-      (InitCategory.isLValue() && T2->isFunctionType()))) {
+       (InitCategory.isPRValue() && (T2->isRecordType() || T2->isArrayType())) ||
+       (InitCategory.isLValue() && T2->isFunctionType()))) {
     ICS.setStandard();
     ICS.Standard.First = ICK_Identity;
     ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base
-- 
2.40.0