SemaAccess.cpp File Reference (original) (raw)

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Functions
static CXXRecordDecl *	FindDeclaringClass (NamedDecl *D)

static bool	MightInstantiateTo (const CXXRecordDecl From, const CXXRecordDecl To)
	Checks whether one class might instantiate to the other.

static AccessResult	IsDerivedFromInclusive (const CXXRecordDecl Derived, const CXXRecordDecl Target)
	Checks whether one class is derived from another, inclusively.

static bool	MightInstantiateTo (Sema &S, DeclContext Context, DeclContext Friend)

static bool	MightInstantiateTo (Sema &S, CanQualType Context, CanQualType Friend)

static bool	MightInstantiateTo (Sema &S, FunctionDecl Context, FunctionDecl Friend)

static bool	MightInstantiateTo (Sema &S, FunctionTemplateDecl Context, FunctionTemplateDecl Friend)

static AccessResult	MatchesFriend (Sema &S, const EffectiveContext &EC, const CXXRecordDecl *Friend)

static AccessResult	MatchesFriend (Sema &S, const EffectiveContext &EC, CanQualType Friend)

static AccessResult	MatchesFriend (Sema &S, const EffectiveContext &EC, ClassTemplateDecl *Friend)
	Determines whether the given friend class template matches anything in the effective context.

static AccessResult	MatchesFriend (Sema &S, const EffectiveContext &EC, FunctionDecl *Friend)
	Determines whether the given friend function matches anything in the effective context.

static AccessResult	MatchesFriend (Sema &S, const EffectiveContext &EC, FunctionTemplateDecl *Friend)
	Determines whether the given friend function template matches anything in the effective context.

static AccessResult	MatchesFriend (Sema &S, const EffectiveContext &EC, FriendDecl *FriendD)
	Determines whether the given friend declaration matches anything in the effective context.

static AccessResult	GetFriendKind (Sema &S, const EffectiveContext &EC, const CXXRecordDecl *Class)

static AccessResult	GetProtectedFriendKind (Sema &S, const EffectiveContext &EC, const CXXRecordDecl InstanceContext, const CXXRecordDecl NamingClass)
	Search for a class P that EC is a friend of, under the constraint InstanceContext <= P if InstanceContext exists, or else NamingClass <= P and with the additional restriction that a protected member of NamingClass would have some natural access in P, which implicitly imposes the constraint that P <= NamingClass.

static AccessResult	HasAccess (Sema &S, const EffectiveContext &EC, const CXXRecordDecl *NamingClass, AccessSpecifier Access, const AccessTarget &Target)

static CXXBasePath *	FindBestPath (Sema &S, const EffectiveContext &EC, AccessTarget &Target, AccessSpecifier FinalAccess, CXXBasePaths &Paths)
	Finds the best path from the naming class to the declaring class, taking friend declarations into account.

static bool	TryDiagnoseProtectedAccess (Sema &S, const EffectiveContext &EC, AccessTarget &Target)
	Given that an entity has protected natural access, check whether access might be denied because of the protected member access restriction.

static void	diagnoseBadDirectAccess (Sema &S, const EffectiveContext &EC, AccessTarget &entity)
	We are unable to access a given declaration due to its direct access control; diagnose that.

static void	DiagnoseAccessPath (Sema &S, const EffectiveContext &EC, AccessTarget &entity)
	Diagnose the path which caused the given declaration or base class to become inaccessible.

static void	DiagnoseBadAccess (Sema &S, SourceLocation Loc, const EffectiveContext &EC, AccessTarget &Entity)

static bool	IsMicrosoftUsingDeclarationAccessBug (Sema &S, SourceLocation AccessLoc, AccessTarget &Entity)
	MSVC has a bug where if during an using declaration name lookup, the declaration found is unaccessible (private) and that declaration was bring into scope via another using declaration whose target declaration is accessible (public) then no error is generated.

static AccessResult	IsAccessible (Sema &S, const EffectiveContext &EC, AccessTarget &Entity)
	Determines whether the accessed entity is accessible.

static void	DelayDependentAccess (Sema &S, const EffectiveContext &EC, SourceLocation Loc, const AccessTarget &Entity)

static AccessResult	CheckEffectiveAccess (Sema &S, const EffectiveContext &EC, SourceLocation Loc, AccessTarget &Entity)
	Checks access to an entity from the given effective context.

static Sema::AccessResult	CheckAccess (Sema &S, SourceLocation Loc, AccessTarget &Entity)

◆ AccessResult

A copy of Sema's enum without AR_delayed.

Enumerator
AR_accessible
AR_inaccessible
AR_dependent

Definition at line 30 of file SemaAccess.cpp.

◆ CheckAccess()

Definition at line 1458 of file SemaAccess.cpp.

References clang::Sema::DelayedDiagnostics::add(), clang::Sema::AR_accessible, AR_accessible, clang::Sema::AR_delayed, clang::Sema::AR_dependent, AR_dependent, clang::Sema::AR_inaccessible, AR_inaccessible, clang::AS_public, CheckEffectiveAccess(), clang::Sema::CurContext, clang::Sema::DelayedDiagnostics, clang::Sema::getCurScope(), clang::Scope::getParent(), clang::Scope::isFriendScope(), Loc, clang::sema::DelayedDiagnostic::makeAccess(), and clang::Sema::DelayedDiagnostics::shouldDelayDiagnostics().

◆ CheckEffectiveAccess()

Checks access to an entity from the given effective context.

Definition at line 1431 of file SemaAccess.cpp.

References AR_accessible, AR_dependent, AR_inaccessible, clang::AS_public, DelayDependentAccess(), DiagnoseBadAccess(), clang::Sema::getLangOpts(), IsAccessible(), IsMicrosoftUsingDeclarationAccessBug(), and Loc.

Referenced by CheckAccess(), clang::Sema::CheckBaseClassAccess(), clang::Sema::CheckFriendAccess(), and clang::Sema::HandleDelayedAccessCheck().

◆ DelayDependentAccess()

static void DelayDependentAccess ( Sema & S, const EffectiveContext & EC, SourceLocation Loc, const AccessTarget & Entity )	static

◆ DiagnoseAccessPath()

static void DiagnoseAccessPath ( Sema & S, const EffectiveContext & EC, AccessTarget & entity )	static

Diagnose the path which caused the given declaration or base class to become inaccessible.

Definition at line 1170 of file SemaAccess.cpp.

References clang::CXXBasePath::Access, AR_accessible, AR_dependent, AR_inaccessible, clang::AS_none, clang::AS_private, clang::AS_protected, clang::AS_public, D, clang::SemaBase::Diag(), diagnoseBadDirectAccess(), FindBestPath(), clang::Decl::getAccess(), clang::CXXBaseSpecifier::getAccessSpecifier(), clang::CXXBaseSpecifier::getAccessSpecifierAsWritten(), clang::SourceRange::getBegin(), clang::CXXRecordDecl::getCanonicalDecl(), clang::CXXBaseSpecifier::getSourceRange(), and HasAccess().

Referenced by DiagnoseBadAccess().

◆ DiagnoseBadAccess()

static void DiagnoseBadAccess ( Sema & S, SourceLocation Loc, const EffectiveContext & EC, AccessTarget & Entity )	static

◆ diagnoseBadDirectAccess()

static void diagnoseBadDirectAccess ( Sema & S, const EffectiveContext & EC, AccessTarget & entity )	static

We are unable to access a given declaration due to its direct access control; diagnose that.

Definition at line 1113 of file SemaAccess.cpp.

References clang::AS_protected, D, clang::DeclContext::decls(), clang::SemaBase::Diag(), FindDeclaringClass(), clang::Decl::getAccess(), clang::Decl::getDeclContext(), clang::Decl::getLocation(), clang::DeclContext::getParent(), clang::Decl::getPreviousDecl(), clang::Decl::isOutOfLine(), and TryDiagnoseProtectedAccess().

Referenced by DiagnoseAccessPath().

◆ FindBestPath()

Finds the best path from the naming class to the declaring class, taking friend declarations into account.

C++0x [class.access.base]p5: A member m is accessible at the point R when named in class N if [M1] m as a member of N is public, or [M2] m as a member of N is private, and R occurs in a member or friend of class N, or [M3] m as a member of N is protected, and R occurs in a member or friend of class N, or in a member or friend of a class P derived from N, where m as a member of P is public, private, or protected, or [M4] there exists a base class B of N that is accessible at R, and m is accessible at R when named in class B.

C++0x [class.access.base]p4: A base class B of N is accessible at R, if [B1] an invented public member of B would be a public member of N, or [B2] R occurs in a member or friend of class N, and an invented public member of B would be a private or protected member of N, or [B3] R occurs in a member or friend of a class P derived from N, and an invented public member of B would be a private or protected member of P, or [B4] there exists a class S such that B is a base class of S accessible at R and S is a base class of N accessible at R.

Along a single inheritance path we can restate both of these iteratively:

First, we note that M1-4 are equivalent to B1-4 if the member is treated as a notional base of its declaring class with inheritance access equivalent to the member's access. Therefore we need only ask whether a class B is accessible from a class N in context R.

Let B_1 .. B_n be the inheritance path in question (i.e. where B_1 = N, B_n = B, and for all i, B_{i+1} is a direct base class of B_i). For i in 1..n, we will calculate ACAB(i), the access to the closest accessible base in the path: Access(a, b) = (* access on the base specifier from a to b *) Merge(a, forbidden) = forbidden Merge(a, private) = forbidden Merge(a, b) = min(a,b) Accessible(c, forbidden) = false Accessible(c, private) = (R is c) || IsFriend(c, R) Accessible(c, protected) = (R derived from c) || IsFriend(c, R) Accessible(c, public) = true ACAB(n) = public ACAB(i) = let AccessToBase = Merge(Access(B_i, B_{i+1}), ACAB(i+1)) in if Accessible(B_i, AccessToBase) then public else AccessToBase

B is an accessible base of N at R iff ACAB(1) = public.

Parameters

FinalAccess	the access of the "final step", or AS_public if there is no final step.

Returns

null if friendship is dependent

Definition at line 946 of file SemaAccess.cpp.

References clang::CXXBasePath::Access, AR_accessible, AR_dependent, AR_inaccessible, clang::AS_none, clang::AS_private, clang::AS_public, E, clang::CXXRecordDecl::getCanonicalDecl(), HasAccess(), and clang::CXXRecordDecl::isDerivedFrom().

Referenced by DiagnoseAccessPath(), and IsAccessible().

◆ FindDeclaringClass()

◆ GetFriendKind()

◆ GetProtectedFriendKind()

Search for a class P that EC is a friend of, under the constraint InstanceContext <= P if InstanceContext exists, or else NamingClass <= P and with the additional restriction that a protected member of NamingClass would have some natural access in P, which implicitly imposes the constraint that P <= NamingClass.

This isn't quite the condition laid out in the standard. Instead of saying that a notional protected member of NamingClass would have to have some natural access in P, it says the actual target has to have some natural access in P, which opens up the possibility that the target (which is not necessarily a member of NamingClass) might be more accessible along some path not passing through it. That's really a bad idea, though, because it introduces two problems:

Most importantly, it breaks encapsulation because you can access a forbidden base class's members by directly subclassing it elsewhere.
It also makes access substantially harder to compute because it breaks the hill-climbing algorithm: knowing that the target is accessible in some base class would no longer let you change the question solely to whether the base class is accessible, because the original target might have been more accessible because of crazy subclassing. So we don't implement that.

Definition at line 730 of file SemaAccess.cpp.

References AR_accessible, AR_dependent, AR_inaccessible, clang::CXXRecordDecl::getCanonicalDecl(), and GetFriendKind().

Referenced by HasAccess().