PR13381: consider cv-qualifiers on a class member's type when determining which

constructor will be used for moving that object, in the computation of its
exception specification.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@160417 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Sema/Sema.h

@@ -2124,9 +2124,10 @@ public:
                                                unsigned Quals);
   CXXMethodDecl *LookupCopyingAssignment(CXXRecordDecl *Class, unsigned Quals,
                                          bool RValueThis, unsigned ThisQuals);
-  CXXConstructorDecl *LookupMovingConstructor(CXXRecordDecl *Class);
-  CXXMethodDecl *LookupMovingAssignment(CXXRecordDecl *Class, bool RValueThis,
-                                        unsigned ThisQuals);
+  CXXConstructorDecl *LookupMovingConstructor(CXXRecordDecl *Class,
+                                              unsigned Quals);
+  CXXMethodDecl *LookupMovingAssignment(CXXRecordDecl *Class, unsigned Quals,
+                                        bool RValueThis, unsigned ThisQuals);
   CXXDestructorDecl *LookupDestructor(CXXRecordDecl *Class);
 
   LiteralOperatorLookupResult LookupLiteralOperator(Scope *S, LookupResult &R,

lib/Sema/SemaDeclCXX.cpp

@@ -7559,7 +7559,9 @@ Sema::ComputeDefaultedCopyAssignmentExceptionSpecAndConst(
     QualType FieldType = Context.getBaseElementType(Field->getType());
     if (CXXRecordDecl *FieldClassDecl = FieldType->getAsCXXRecordDecl()) {
       if (CXXMethodDecl *CopyAssign =
-          LookupCopyingAssignment(FieldClassDecl, ArgQuals, false, 0))
+          LookupCopyingAssignment(FieldClassDecl,
+                                  ArgQuals | FieldType.getCVRQualifiers(),
+                                  false, 0))
         ExceptSpec.CalledDecl(Field->getLocation(), CopyAssign);
     }
   }
@@ -7966,7 +7968,7 @@ Sema::ComputeDefaultedMoveAssignmentExceptionSpec(CXXRecordDecl *ClassDecl) {
     CXXRecordDecl *BaseClassDecl
       = cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
     if (CXXMethodDecl *MoveAssign = LookupMovingAssignment(BaseClassDecl,
-                                                           false, 0))
+                                                           0, false, 0))
       ExceptSpec.CalledDecl(Base->getLocStart(), MoveAssign);
   }
 
@@ -7976,7 +7978,7 @@ Sema::ComputeDefaultedMoveAssignmentExceptionSpec(CXXRecordDecl *ClassDecl) {
     CXXRecordDecl *BaseClassDecl
       = cast<CXXRecordDecl>(Base->getType()->getAs<RecordType>()->getDecl());
     if (CXXMethodDecl *MoveAssign = LookupMovingAssignment(BaseClassDecl,
-                                                           false, 0))
+                                                           0, false, 0))
       ExceptSpec.CalledDecl(Base->getLocStart(), MoveAssign);
   }
 
@@ -7986,8 +7988,10 @@ Sema::ComputeDefaultedMoveAssignmentExceptionSpec(CXXRecordDecl *ClassDecl) {
        ++Field) {
     QualType FieldType = Context.getBaseElementType(Field->getType());
     if (CXXRecordDecl *FieldClassDecl = FieldType->getAsCXXRecordDecl()) {
-      if (CXXMethodDecl *MoveAssign = LookupMovingAssignment(FieldClassDecl,
-                                                             false, 0))
+      if (CXXMethodDecl *MoveAssign =
+              LookupMovingAssignment(FieldClassDecl,
+                                     FieldType.getCVRQualifiers(),
+                                     false, 0))
         ExceptSpec.CalledDecl(Field->getLocation(), MoveAssign);
     }
   }
@@ -8580,7 +8584,8 @@ Sema::ComputeDefaultedCopyCtorExceptionSpecAndConst(CXXRecordDecl *ClassDecl) {
     QualType FieldType = Context.getBaseElementType(Field->getType());
     if (CXXRecordDecl *FieldClassDecl = FieldType->getAsCXXRecordDecl()) {
       if (CXXConstructorDecl *CopyConstructor =
-        LookupCopyingConstructor(FieldClassDecl, Quals))
+              LookupCopyingConstructor(FieldClassDecl,
+                                       Quals | FieldType.getCVRQualifiers()))
       ExceptSpec.CalledDecl(Field->getLocation(), CopyConstructor);
     }
   }
@@ -8708,7 +8713,8 @@ Sema::ComputeDefaultedMoveCtorExceptionSpec(CXXRecordDecl *ClassDecl) {
     
     if (const RecordType *BaseType = B->getType()->getAs<RecordType>()) {
       CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
-      CXXConstructorDecl *Constructor = LookupMovingConstructor(BaseClassDecl);
+      CXXConstructorDecl *Constructor =
+          LookupMovingConstructor(BaseClassDecl, 0);
       // If this is a deleted function, add it anyway. This might be conformant
       // with the standard. This might not. I'm not sure. It might not matter.
       if (Constructor)
@@ -8722,7 +8728,8 @@ Sema::ComputeDefaultedMoveCtorExceptionSpec(CXXRecordDecl *ClassDecl) {
        B != BEnd; ++B) {
     if (const RecordType *BaseType = B->getType()->getAs<RecordType>()) {
       CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
-      CXXConstructorDecl *Constructor = LookupMovingConstructor(BaseClassDecl);
+      CXXConstructorDecl *Constructor =
+          LookupMovingConstructor(BaseClassDecl, 0);
       // If this is a deleted function, add it anyway. This might be conformant
       // with the standard. This might not. I'm not sure. It might not matter.
       if (Constructor)
@@ -8734,10 +8741,10 @@ Sema::ComputeDefaultedMoveCtorExceptionSpec(CXXRecordDecl *ClassDecl) {
   for (RecordDecl::field_iterator F = ClassDecl->field_begin(),
                                FEnd = ClassDecl->field_end();
        F != FEnd; ++F) {
-    if (const RecordType *RecordTy
-              = Context.getBaseElementType(F->getType())->getAs<RecordType>()) {
-      CXXRecordDecl *FieldRecDecl = cast<CXXRecordDecl>(RecordTy->getDecl());
-      CXXConstructorDecl *Constructor = LookupMovingConstructor(FieldRecDecl);
+    QualType FieldType = Context.getBaseElementType(F->getType());
+    if (CXXRecordDecl *FieldRecDecl = FieldType->getAsCXXRecordDecl()) {
+      CXXConstructorDecl *Constructor =
+          LookupMovingConstructor(FieldRecDecl, FieldType.getCVRQualifiers());
       // If this is a deleted function, add it anyway. This might be conformant
       // with the standard. This might not. I'm not sure. It might not matter.
       // In particular, the problem is that this function never gets called. It

lib/Sema/SemaLookup.cpp

@@ -2432,10 +2432,11 @@ CXXConstructorDecl *Sema::LookupCopyingConstructor(CXXRecordDecl *Class,
 }
 
 /// \brief Look up the moving constructor for the given class.
-CXXConstructorDecl *Sema::LookupMovingConstructor(CXXRecordDecl *Class) {
+CXXConstructorDecl *Sema::LookupMovingConstructor(CXXRecordDecl *Class,
+                                                  unsigned Quals) {
   SpecialMemberOverloadResult *Result =
-    LookupSpecialMember(Class, CXXMoveConstructor, false,
-                        false, false, false, false);
+    LookupSpecialMember(Class, CXXMoveConstructor, Quals & Qualifiers::Const,
+                        Quals & Qualifiers::Volatile, false, false, false);
 
   return cast_or_null<CXXConstructorDecl>(Result->getMethod());
 }
@@ -2476,12 +2477,14 @@ CXXMethodDecl *Sema::LookupCopyingAssignment(CXXRecordDecl *Class,
 
 /// \brief Look up the moving assignment operator for the given class.
 CXXMethodDecl *Sema::LookupMovingAssignment(CXXRecordDecl *Class,
+                                            unsigned Quals,
                                             bool RValueThis,
                                             unsigned ThisQuals) {
   assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
          "non-const, non-volatile qualifiers for copy assignment this");
   SpecialMemberOverloadResult *Result =
-    LookupSpecialMember(Class, CXXMoveAssignment, false, false, RValueThis,
+    LookupSpecialMember(Class, CXXMoveAssignment, Quals & Qualifiers::Const,
+                        Quals & Qualifiers::Volatile, RValueThis,
                         ThisQuals & Qualifiers::Const,
                         ThisQuals & Qualifiers::Volatile);
 

test/CXX/except/except.spec/p14.cpp

@@ -39,3 +39,27 @@ struct IC1 {
 // we cannot currently compute the set of thrown types.
 static_assert(noexcept(IC0()), "IC0() does not throw");
 static_assert(!noexcept(IC1()), "IC1() throws");
+
+namespace PR13381 {
+  struct NoThrowMove {
+    NoThrowMove(const NoThrowMove &);
+    NoThrowMove(NoThrowMove &&) noexcept;
+    NoThrowMove &operator=(const NoThrowMove &);
+    NoThrowMove &operator=(NoThrowMove &&) noexcept;
+  };
+  struct NoThrowMoveOnly {
+    NoThrowMoveOnly(NoThrowMoveOnly &&) noexcept;
+    NoThrowMoveOnly &operator=(NoThrowMoveOnly &&) noexcept;
+  };
+  struct X {
+    const NoThrowMove a;
+    NoThrowMoveOnly b;
+
+    static X val();
+    static X &ref();
+  };
+  // These both perform a move, but that copy might throw, because it calls
+  // NoThrowMove's copy constructor (because PR13381::a is const).
+  static_assert(!noexcept(X(X::val())), "");
+  static_assert(!noexcept(X::ref() = X::val()), "");
+}