llvm/clang/lib/Sema/SemaAvailability.cpp

//===--- SemaAvailability.cpp - Availability attribute handling -----------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
//  This file processes the availability attribute.
//
//===----------------------------------------------------------------------===//

#include "clang/AST/Attr.h"
#include "clang/AST/Decl.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/AST/RecursiveASTVisitor.h"
#include "clang/Basic/DiagnosticSema.h"
#include "clang/Basic/IdentifierTable.h"
#include "clang/Basic/LangOptions.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Sema/DelayedDiagnostic.h"
#include "clang/Sema/ScopeInfo.h"
#include "clang/Sema/Sema.h"
#include "clang/Sema/SemaObjC.h"
#include "llvm/ADT/StringRef.h"
#include <optional>

usingnamespaceclang;
usingnamespacesema;

static bool hasMatchingEnvironmentOrNone(const ASTContext &Context,
                                         const AvailabilityAttr *AA) { … }

static const AvailabilityAttr *getAttrForPlatform(ASTContext &Context,
                                                  const Decl *D) { … }

/// The diagnostic we should emit for \c D, and the declaration that
/// originated it, or \c AR_Available.
///
/// \param D The declaration to check.
/// \param Message If non-null, this will be populated with the message from
/// the availability attribute that is selected.
/// \param ClassReceiver If we're checking the method of a class message
/// send, the class. Otherwise nullptr.
static std::pair<AvailabilityResult, const NamedDecl *>
ShouldDiagnoseAvailabilityOfDecl(Sema &S, const NamedDecl *D,
                                 std::string *Message,
                                 ObjCInterfaceDecl *ClassReceiver) { … }


/// whether we should emit a diagnostic for \c K and \c DeclVersion in
/// the context of \c Ctx. For example, we should emit an unavailable diagnostic
/// in a deprecated context, but not the other way around.
static bool ShouldDiagnoseAvailabilityInContext(
    Sema &S, AvailabilityResult K, VersionTuple DeclVersion,
    const IdentifierInfo *DeclEnv, Decl *Ctx, const NamedDecl *OffendingDecl) { … }

static unsigned getAvailabilityDiagnosticKind(
    const ASTContext &Context, const VersionTuple &DeploymentVersion,
    const VersionTuple &DeclVersion, bool HasMatchingEnv) { … }

static NamedDecl *findEnclosingDeclToAnnotate(Decl *OrigCtx) { … }

namespace {

struct AttributeInsertion { … };

} // end anonymous namespace

/// Tries to parse a string as ObjC method name.
///
/// \param Name The string to parse. Expected to originate from availability
/// attribute argument.
/// \param SlotNames The vector that will be populated with slot names. In case
/// of unsuccessful parsing can contain invalid data.
/// \returns A number of method parameters if parsing was successful,
/// std::nullopt otherwise.
static std::optional<unsigned>
tryParseObjCMethodName(StringRef Name, SmallVectorImpl<StringRef> &SlotNames,
                       const LangOptions &LangOpts) { … }

/// Returns a source location in which it's appropriate to insert a new
/// attribute for the given declaration \D.
static std::optional<AttributeInsertion>
createAttributeInsertion(const NamedDecl *D, const SourceManager &SM,
                         const LangOptions &LangOpts) { … }

/// Actually emit an availability diagnostic for a reference to an unavailable
/// decl.
///
/// \param Ctx The context that the reference occurred in
/// \param ReferringDecl The exact declaration that was referenced.
/// \param OffendingDecl A related decl to \c ReferringDecl that has an
/// availability attribute corresponding to \c K attached to it. Note that this
/// may not be the same as ReferringDecl, i.e. if an EnumDecl is annotated and
/// we refer to a member EnumConstantDecl, ReferringDecl is the EnumConstantDecl
/// and OffendingDecl is the EnumDecl.
static void DoEmitAvailabilityWarning(Sema &S, AvailabilityResult K,
                                      Decl *Ctx, const NamedDecl *ReferringDecl,
                                      const NamedDecl *OffendingDecl,
                                      StringRef Message,
                                      ArrayRef<SourceLocation> Locs,
                                      const ObjCInterfaceDecl *UnknownObjCClass,
                                      const ObjCPropertyDecl *ObjCProperty,
                                      bool ObjCPropertyAccess) { … }

void Sema::handleDelayedAvailabilityCheck(DelayedDiagnostic &DD, Decl *Ctx) { … }

static void EmitAvailabilityWarning(Sema &S, AvailabilityResult AR,
                                    const NamedDecl *ReferringDecl,
                                    const NamedDecl *OffendingDecl,
                                    StringRef Message,
                                    ArrayRef<SourceLocation> Locs,
                                    const ObjCInterfaceDecl *UnknownObjCClass,
                                    const ObjCPropertyDecl *ObjCProperty,
                                    bool ObjCPropertyAccess) { … }

namespace {

/// Returns true if the given statement can be a body-like child of \p Parent.
bool isBodyLikeChildStmt(const Stmt *S, const Stmt *Parent) { … }

class StmtUSEFinder : public RecursiveASTVisitor<StmtUSEFinder> { … };

/// Traverses the AST and finds the last statement that used a given
/// declaration.
class LastDeclUSEFinder : public RecursiveASTVisitor<LastDeclUSEFinder> { … };

/// This class implements -Wunguarded-availability.
///
/// This is done with a traversal of the AST of a function that makes reference
/// to a partially available declaration. Whenever we encounter an \c if of the
/// form: \c if(@available(...)), we use the version from the condition to visit
/// the then statement.
class DiagnoseUnguardedAvailability
    : public RecursiveASTVisitor<DiagnoseUnguardedAvailability> { … };

void DiagnoseUnguardedAvailability::DiagnoseDeclAvailability(
    NamedDecl *D, SourceRange Range, ObjCInterfaceDecl *ReceiverClass) { … }

bool DiagnoseUnguardedAvailability::VisitTypeLoc(TypeLoc Ty) { … }

bool DiagnoseUnguardedAvailability::TraverseIfStmt(IfStmt *If) { … }

} // end anonymous namespace

void Sema::DiagnoseUnguardedAvailabilityViolations(Decl *D) { … }

FunctionScopeInfo *Sema::getCurFunctionAvailabilityContext() { … }

void Sema::DiagnoseAvailabilityOfDecl(NamedDecl *D,
                                      ArrayRef<SourceLocation> Locs,
                                      const ObjCInterfaceDecl *UnknownObjCClass,
                                      bool ObjCPropertyAccess,
                                      bool AvoidPartialAvailabilityChecks,
                                      ObjCInterfaceDecl *ClassReceiver) { … }