llvm-project/clang/lib/Parse/ParseExprCXX.cpp

1284 lines
44 KiB
C++

//===--- ParseExprCXX.cpp - C++ Expression Parsing ------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the Expression parsing implementation for C++.
//
//===----------------------------------------------------------------------===//
#include "clang/Parse/ParseDiagnostic.h"
#include "clang/Parse/Parser.h"
#include "clang/Parse/DeclSpec.h"
using namespace clang;
/// \brief Parse global scope or nested-name-specifier if present.
///
/// Parses a C++ global scope specifier ('::') or nested-name-specifier (which
/// may be preceded by '::'). Note that this routine will not parse ::new or
/// ::delete; it will just leave them in the token stream.
///
/// '::'[opt] nested-name-specifier
/// '::'
///
/// nested-name-specifier:
/// type-name '::'
/// namespace-name '::'
/// nested-name-specifier identifier '::'
/// nested-name-specifier 'template'[opt] simple-template-id '::'
///
///
/// \param SS the scope specifier that will be set to the parsed
/// nested-name-specifier (or empty)
///
/// \param ObjectType if this nested-name-specifier is being parsed following
/// the "." or "->" of a member access expression, this parameter provides the
/// type of the object whose members are being accessed.
///
/// \param EnteringContext whether we will be entering into the context of
/// the nested-name-specifier after parsing it.
///
/// \returns true if a scope specifier was parsed.
bool Parser::ParseOptionalCXXScopeSpecifier(CXXScopeSpec &SS,
Action::TypeTy *ObjectType,
bool EnteringContext) {
assert(getLang().CPlusPlus &&
"Call sites of this function should be guarded by checking for C++");
if (Tok.is(tok::annot_cxxscope)) {
SS.setScopeRep(Tok.getAnnotationValue());
SS.setRange(Tok.getAnnotationRange());
ConsumeToken();
return true;
}
bool HasScopeSpecifier = false;
if (Tok.is(tok::coloncolon)) {
// ::new and ::delete aren't nested-name-specifiers.
tok::TokenKind NextKind = NextToken().getKind();
if (NextKind == tok::kw_new || NextKind == tok::kw_delete)
return false;
// '::' - Global scope qualifier.
SourceLocation CCLoc = ConsumeToken();
SS.setBeginLoc(CCLoc);
SS.setScopeRep(Actions.ActOnCXXGlobalScopeSpecifier(CurScope, CCLoc));
SS.setEndLoc(CCLoc);
HasScopeSpecifier = true;
}
while (true) {
if (HasScopeSpecifier) {
// C++ [basic.lookup.classref]p5:
// If the qualified-id has the form
//
// ::class-name-or-namespace-name::...
//
// the class-name-or-namespace-name is looked up in global scope as a
// class-name or namespace-name.
//
// To implement this, we clear out the object type as soon as we've
// seen a leading '::' or part of a nested-name-specifier.
ObjectType = 0;
if (Tok.is(tok::code_completion)) {
// Code completion for a nested-name-specifier, where the code
// code completion token follows the '::'.
Actions.CodeCompleteQualifiedId(CurScope, SS, EnteringContext);
ConsumeToken();
}
}
// nested-name-specifier:
// nested-name-specifier 'template'[opt] simple-template-id '::'
// Parse the optional 'template' keyword, then make sure we have
// 'identifier <' after it.
if (Tok.is(tok::kw_template)) {
// If we don't have a scope specifier or an object type, this isn't a
// nested-name-specifier, since they aren't allowed to start with
// 'template'.
if (!HasScopeSpecifier && !ObjectType)
break;
SourceLocation TemplateKWLoc = ConsumeToken();
if (Tok.isNot(tok::identifier)) {
Diag(Tok.getLocation(),
diag::err_id_after_template_in_nested_name_spec)
<< SourceRange(TemplateKWLoc);
break;
}
if (NextToken().isNot(tok::less)) {
Diag(NextToken().getLocation(),
diag::err_less_after_template_name_in_nested_name_spec)
<< Tok.getIdentifierInfo()->getName()
<< SourceRange(TemplateKWLoc, Tok.getLocation());
break;
}
TemplateTy Template
= Actions.ActOnDependentTemplateName(TemplateKWLoc,
*Tok.getIdentifierInfo(),
Tok.getLocation(), SS,
ObjectType);
if (!Template)
break;
if (AnnotateTemplateIdToken(Template, TNK_Dependent_template_name,
&SS, TemplateKWLoc, false))
break;
continue;
}
if (Tok.is(tok::annot_template_id) && NextToken().is(tok::coloncolon)) {
// We have
//
// simple-template-id '::'
//
// So we need to check whether the simple-template-id is of the
// right kind (it should name a type or be dependent), and then
// convert it into a type within the nested-name-specifier.
TemplateIdAnnotation *TemplateId
= static_cast<TemplateIdAnnotation *>(Tok.getAnnotationValue());
if (TemplateId->Kind == TNK_Type_template ||
TemplateId->Kind == TNK_Dependent_template_name) {
AnnotateTemplateIdTokenAsType(&SS);
assert(Tok.is(tok::annot_typename) &&
"AnnotateTemplateIdTokenAsType isn't working");
Token TypeToken = Tok;
ConsumeToken();
assert(Tok.is(tok::coloncolon) && "NextToken() not working properly!");
SourceLocation CCLoc = ConsumeToken();
if (!HasScopeSpecifier) {
SS.setBeginLoc(TypeToken.getLocation());
HasScopeSpecifier = true;
}
if (TypeToken.getAnnotationValue())
SS.setScopeRep(
Actions.ActOnCXXNestedNameSpecifier(CurScope, SS,
TypeToken.getAnnotationValue(),
TypeToken.getAnnotationRange(),
CCLoc));
else
SS.setScopeRep(0);
SS.setEndLoc(CCLoc);
continue;
}
assert(false && "FIXME: Only type template names supported here");
}
// The rest of the nested-name-specifier possibilities start with
// tok::identifier.
if (Tok.isNot(tok::identifier))
break;
IdentifierInfo &II = *Tok.getIdentifierInfo();
// nested-name-specifier:
// type-name '::'
// namespace-name '::'
// nested-name-specifier identifier '::'
Token Next = NextToken();
if (Next.is(tok::coloncolon)) {
// We have an identifier followed by a '::'. Lookup this name
// as the name in a nested-name-specifier.
SourceLocation IdLoc = ConsumeToken();
assert(Tok.is(tok::coloncolon) && "NextToken() not working properly!");
SourceLocation CCLoc = ConsumeToken();
if (!HasScopeSpecifier) {
SS.setBeginLoc(IdLoc);
HasScopeSpecifier = true;
}
if (SS.isInvalid())
continue;
SS.setScopeRep(
Actions.ActOnCXXNestedNameSpecifier(CurScope, SS, IdLoc, CCLoc, II,
ObjectType, EnteringContext));
SS.setEndLoc(CCLoc);
continue;
}
// nested-name-specifier:
// type-name '<'
if (Next.is(tok::less)) {
TemplateTy Template;
if (TemplateNameKind TNK = Actions.isTemplateName(CurScope, II,
Tok.getLocation(),
&SS,
ObjectType,
EnteringContext,
Template)) {
// We have found a template name, so annotate this this token
// with a template-id annotation. We do not permit the
// template-id to be translated into a type annotation,
// because some clients (e.g., the parsing of class template
// specializations) still want to see the original template-id
// token.
if (AnnotateTemplateIdToken(Template, TNK, &SS, SourceLocation(),
false))
break;
continue;
}
}
// We don't have any tokens that form the beginning of a
// nested-name-specifier, so we're done.
break;
}
return HasScopeSpecifier;
}
/// ParseCXXIdExpression - Handle id-expression.
///
/// id-expression:
/// unqualified-id
/// qualified-id
///
/// unqualified-id:
/// identifier
/// operator-function-id
/// conversion-function-id [TODO]
/// '~' class-name [TODO]
/// template-id
///
/// qualified-id:
/// '::'[opt] nested-name-specifier 'template'[opt] unqualified-id
/// '::' identifier
/// '::' operator-function-id
/// '::' template-id
///
/// nested-name-specifier:
/// type-name '::'
/// namespace-name '::'
/// nested-name-specifier identifier '::'
/// nested-name-specifier 'template'[opt] simple-template-id '::' [TODO]
///
/// NOTE: The standard specifies that, for qualified-id, the parser does not
/// expect:
///
/// '::' conversion-function-id
/// '::' '~' class-name
///
/// This may cause a slight inconsistency on diagnostics:
///
/// class C {};
/// namespace A {}
/// void f() {
/// :: A :: ~ C(); // Some Sema error about using destructor with a
/// // namespace.
/// :: ~ C(); // Some Parser error like 'unexpected ~'.
/// }
///
/// We simplify the parser a bit and make it work like:
///
/// qualified-id:
/// '::'[opt] nested-name-specifier 'template'[opt] unqualified-id
/// '::' unqualified-id
///
/// That way Sema can handle and report similar errors for namespaces and the
/// global scope.
///
/// The isAddressOfOperand parameter indicates that this id-expression is a
/// direct operand of the address-of operator. This is, besides member contexts,
/// the only place where a qualified-id naming a non-static class member may
/// appear.
///
Parser::OwningExprResult Parser::ParseCXXIdExpression(bool isAddressOfOperand) {
// qualified-id:
// '::'[opt] nested-name-specifier 'template'[opt] unqualified-id
// '::' unqualified-id
//
CXXScopeSpec SS;
ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/0, false);
// unqualified-id:
// identifier
// operator-function-id
// conversion-function-id
// '~' class-name [TODO]
// template-id
//
switch (Tok.getKind()) {
default:
return ExprError(Diag(Tok, diag::err_expected_unqualified_id));
case tok::identifier: {
// Consume the identifier so that we can see if it is followed by a '('.
IdentifierInfo &II = *Tok.getIdentifierInfo();
SourceLocation L = ConsumeToken();
return Actions.ActOnIdentifierExpr(CurScope, L, II, Tok.is(tok::l_paren),
&SS, isAddressOfOperand);
}
case tok::kw_operator: {
SourceLocation OperatorLoc = Tok.getLocation();
if (OverloadedOperatorKind Op = TryParseOperatorFunctionId())
return Actions.ActOnCXXOperatorFunctionIdExpr(
CurScope, OperatorLoc, Op, Tok.is(tok::l_paren), SS,
isAddressOfOperand);
if (TypeTy *Type = ParseConversionFunctionId())
return Actions.ActOnCXXConversionFunctionExpr(CurScope, OperatorLoc, Type,
Tok.is(tok::l_paren), SS,
isAddressOfOperand);
// We already complained about a bad conversion-function-id,
// above.
return ExprError();
}
case tok::annot_template_id: {
TemplateIdAnnotation *TemplateId
= static_cast<TemplateIdAnnotation *>(Tok.getAnnotationValue());
assert((TemplateId->Kind == TNK_Function_template ||
TemplateId->Kind == TNK_Dependent_template_name) &&
"A template type name is not an ID expression");
ASTTemplateArgsPtr TemplateArgsPtr(Actions,
TemplateId->getTemplateArgs(),
TemplateId->getTemplateArgIsType(),
TemplateId->NumArgs);
OwningExprResult Result
= Actions.ActOnTemplateIdExpr(TemplateTy::make(TemplateId->Template),
TemplateId->TemplateNameLoc,
TemplateId->LAngleLoc,
TemplateArgsPtr,
TemplateId->getTemplateArgLocations(),
TemplateId->RAngleLoc);
ConsumeToken(); // Consume the template-id token
return move(Result);
}
} // switch.
assert(0 && "The switch was supposed to take care everything.");
}
/// ParseCXXCasts - This handles the various ways to cast expressions to another
/// type.
///
/// postfix-expression: [C++ 5.2p1]
/// 'dynamic_cast' '<' type-name '>' '(' expression ')'
/// 'static_cast' '<' type-name '>' '(' expression ')'
/// 'reinterpret_cast' '<' type-name '>' '(' expression ')'
/// 'const_cast' '<' type-name '>' '(' expression ')'
///
Parser::OwningExprResult Parser::ParseCXXCasts() {
tok::TokenKind Kind = Tok.getKind();
const char *CastName = 0; // For error messages
switch (Kind) {
default: assert(0 && "Unknown C++ cast!"); abort();
case tok::kw_const_cast: CastName = "const_cast"; break;
case tok::kw_dynamic_cast: CastName = "dynamic_cast"; break;
case tok::kw_reinterpret_cast: CastName = "reinterpret_cast"; break;
case tok::kw_static_cast: CastName = "static_cast"; break;
}
SourceLocation OpLoc = ConsumeToken();
SourceLocation LAngleBracketLoc = Tok.getLocation();
if (ExpectAndConsume(tok::less, diag::err_expected_less_after, CastName))
return ExprError();
TypeResult CastTy = ParseTypeName();
SourceLocation RAngleBracketLoc = Tok.getLocation();
if (ExpectAndConsume(tok::greater, diag::err_expected_greater))
return ExprError(Diag(LAngleBracketLoc, diag::note_matching) << "<");
SourceLocation LParenLoc = Tok.getLocation(), RParenLoc;
if (ExpectAndConsume(tok::l_paren, diag::err_expected_lparen_after, CastName))
return ExprError();
OwningExprResult Result = ParseExpression();
// Match the ')'.
if (Result.isInvalid())
SkipUntil(tok::r_paren);
if (Tok.is(tok::r_paren))
RParenLoc = ConsumeParen();
else
MatchRHSPunctuation(tok::r_paren, LParenLoc);
if (!Result.isInvalid() && !CastTy.isInvalid())
Result = Actions.ActOnCXXNamedCast(OpLoc, Kind,
LAngleBracketLoc, CastTy.get(),
RAngleBracketLoc,
LParenLoc, move(Result), RParenLoc);
return move(Result);
}
/// ParseCXXTypeid - This handles the C++ typeid expression.
///
/// postfix-expression: [C++ 5.2p1]
/// 'typeid' '(' expression ')'
/// 'typeid' '(' type-id ')'
///
Parser::OwningExprResult Parser::ParseCXXTypeid() {
assert(Tok.is(tok::kw_typeid) && "Not 'typeid'!");
SourceLocation OpLoc = ConsumeToken();
SourceLocation LParenLoc = Tok.getLocation();
SourceLocation RParenLoc;
// typeid expressions are always parenthesized.
if (ExpectAndConsume(tok::l_paren, diag::err_expected_lparen_after,
"typeid"))
return ExprError();
OwningExprResult Result(Actions);
if (isTypeIdInParens()) {
TypeResult Ty = ParseTypeName();
// Match the ')'.
MatchRHSPunctuation(tok::r_paren, LParenLoc);
if (Ty.isInvalid())
return ExprError();
Result = Actions.ActOnCXXTypeid(OpLoc, LParenLoc, /*isType=*/true,
Ty.get(), RParenLoc);
} else {
// C++0x [expr.typeid]p3:
// When typeid is applied to an expression other than an lvalue of a
// polymorphic class type [...] The expression is an unevaluated
// operand (Clause 5).
//
// Note that we can't tell whether the expression is an lvalue of a
// polymorphic class type until after we've parsed the expression, so
// we the expression is potentially potentially evaluated.
EnterExpressionEvaluationContext Unevaluated(Actions,
Action::PotentiallyPotentiallyEvaluated);
Result = ParseExpression();
// Match the ')'.
if (Result.isInvalid())
SkipUntil(tok::r_paren);
else {
MatchRHSPunctuation(tok::r_paren, LParenLoc);
Result = Actions.ActOnCXXTypeid(OpLoc, LParenLoc, /*isType=*/false,
Result.release(), RParenLoc);
}
}
return move(Result);
}
/// ParseCXXBoolLiteral - This handles the C++ Boolean literals.
///
/// boolean-literal: [C++ 2.13.5]
/// 'true'
/// 'false'
Parser::OwningExprResult Parser::ParseCXXBoolLiteral() {
tok::TokenKind Kind = Tok.getKind();
return Actions.ActOnCXXBoolLiteral(ConsumeToken(), Kind);
}
/// ParseThrowExpression - This handles the C++ throw expression.
///
/// throw-expression: [C++ 15]
/// 'throw' assignment-expression[opt]
Parser::OwningExprResult Parser::ParseThrowExpression() {
assert(Tok.is(tok::kw_throw) && "Not throw!");
SourceLocation ThrowLoc = ConsumeToken(); // Eat the throw token.
// If the current token isn't the start of an assignment-expression,
// then the expression is not present. This handles things like:
// "C ? throw : (void)42", which is crazy but legal.
switch (Tok.getKind()) { // FIXME: move this predicate somewhere common.
case tok::semi:
case tok::r_paren:
case tok::r_square:
case tok::r_brace:
case tok::colon:
case tok::comma:
return Actions.ActOnCXXThrow(ThrowLoc, ExprArg(Actions));
default:
OwningExprResult Expr(ParseAssignmentExpression());
if (Expr.isInvalid()) return move(Expr);
return Actions.ActOnCXXThrow(ThrowLoc, move(Expr));
}
}
/// ParseCXXThis - This handles the C++ 'this' pointer.
///
/// C++ 9.3.2: In the body of a non-static member function, the keyword this is
/// a non-lvalue expression whose value is the address of the object for which
/// the function is called.
Parser::OwningExprResult Parser::ParseCXXThis() {
assert(Tok.is(tok::kw_this) && "Not 'this'!");
SourceLocation ThisLoc = ConsumeToken();
return Actions.ActOnCXXThis(ThisLoc);
}
/// ParseCXXTypeConstructExpression - Parse construction of a specified type.
/// Can be interpreted either as function-style casting ("int(x)")
/// or class type construction ("ClassType(x,y,z)")
/// or creation of a value-initialized type ("int()").
///
/// postfix-expression: [C++ 5.2p1]
/// simple-type-specifier '(' expression-list[opt] ')' [C++ 5.2.3]
/// typename-specifier '(' expression-list[opt] ')' [TODO]
///
Parser::OwningExprResult
Parser::ParseCXXTypeConstructExpression(const DeclSpec &DS) {
Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
TypeTy *TypeRep = Actions.ActOnTypeName(CurScope, DeclaratorInfo).get();
assert(Tok.is(tok::l_paren) && "Expected '('!");
SourceLocation LParenLoc = ConsumeParen();
ExprVector Exprs(Actions);
CommaLocsTy CommaLocs;
if (Tok.isNot(tok::r_paren)) {
if (ParseExpressionList(Exprs, CommaLocs)) {
SkipUntil(tok::r_paren);
return ExprError();
}
}
// Match the ')'.
SourceLocation RParenLoc = MatchRHSPunctuation(tok::r_paren, LParenLoc);
// TypeRep could be null, if it references an invalid typedef.
if (!TypeRep)
return ExprError();
assert((Exprs.size() == 0 || Exprs.size()-1 == CommaLocs.size())&&
"Unexpected number of commas!");
return Actions.ActOnCXXTypeConstructExpr(DS.getSourceRange(), TypeRep,
LParenLoc, move_arg(Exprs),
CommaLocs.data(), RParenLoc);
}
/// ParseCXXCondition - if/switch/while/for condition expression.
///
/// condition:
/// expression
/// type-specifier-seq declarator '=' assignment-expression
/// [GNU] type-specifier-seq declarator simple-asm-expr[opt] attributes[opt]
/// '=' assignment-expression
///
Parser::OwningExprResult Parser::ParseCXXCondition() {
if (!isCXXConditionDeclaration())
return ParseExpression(); // expression
SourceLocation StartLoc = Tok.getLocation();
// type-specifier-seq
DeclSpec DS;
ParseSpecifierQualifierList(DS);
// declarator
Declarator DeclaratorInfo(DS, Declarator::ConditionContext);
ParseDeclarator(DeclaratorInfo);
// simple-asm-expr[opt]
if (Tok.is(tok::kw_asm)) {
SourceLocation Loc;
OwningExprResult AsmLabel(ParseSimpleAsm(&Loc));
if (AsmLabel.isInvalid()) {
SkipUntil(tok::semi);
return ExprError();
}
DeclaratorInfo.setAsmLabel(AsmLabel.release());
DeclaratorInfo.SetRangeEnd(Loc);
}
// If attributes are present, parse them.
if (Tok.is(tok::kw___attribute)) {
SourceLocation Loc;
AttributeList *AttrList = ParseAttributes(&Loc);
DeclaratorInfo.AddAttributes(AttrList, Loc);
}
// '=' assignment-expression
if (Tok.isNot(tok::equal))
return ExprError(Diag(Tok, diag::err_expected_equal_after_declarator));
SourceLocation EqualLoc = ConsumeToken();
OwningExprResult AssignExpr(ParseAssignmentExpression());
if (AssignExpr.isInvalid())
return ExprError();
return Actions.ActOnCXXConditionDeclarationExpr(CurScope, StartLoc,
DeclaratorInfo,EqualLoc,
move(AssignExpr));
}
/// ParseCXXSimpleTypeSpecifier - [C++ 7.1.5.2] Simple type specifiers.
/// This should only be called when the current token is known to be part of
/// simple-type-specifier.
///
/// simple-type-specifier:
/// '::'[opt] nested-name-specifier[opt] type-name
/// '::'[opt] nested-name-specifier 'template' simple-template-id [TODO]
/// char
/// wchar_t
/// bool
/// short
/// int
/// long
/// signed
/// unsigned
/// float
/// double
/// void
/// [GNU] typeof-specifier
/// [C++0x] auto [TODO]
///
/// type-name:
/// class-name
/// enum-name
/// typedef-name
///
void Parser::ParseCXXSimpleTypeSpecifier(DeclSpec &DS) {
DS.SetRangeStart(Tok.getLocation());
const char *PrevSpec;
unsigned DiagID;
SourceLocation Loc = Tok.getLocation();
switch (Tok.getKind()) {
case tok::identifier: // foo::bar
case tok::coloncolon: // ::foo::bar
assert(0 && "Annotation token should already be formed!");
default:
assert(0 && "Not a simple-type-specifier token!");
abort();
// type-name
case tok::annot_typename: {
DS.SetTypeSpecType(DeclSpec::TST_typename, Loc, PrevSpec, DiagID,
Tok.getAnnotationValue());
break;
}
// builtin types
case tok::kw_short:
DS.SetTypeSpecWidth(DeclSpec::TSW_short, Loc, PrevSpec, DiagID);
break;
case tok::kw_long:
DS.SetTypeSpecWidth(DeclSpec::TSW_long, Loc, PrevSpec, DiagID);
break;
case tok::kw_signed:
DS.SetTypeSpecSign(DeclSpec::TSS_signed, Loc, PrevSpec, DiagID);
break;
case tok::kw_unsigned:
DS.SetTypeSpecSign(DeclSpec::TSS_unsigned, Loc, PrevSpec, DiagID);
break;
case tok::kw_void:
DS.SetTypeSpecType(DeclSpec::TST_void, Loc, PrevSpec, DiagID);
break;
case tok::kw_char:
DS.SetTypeSpecType(DeclSpec::TST_char, Loc, PrevSpec, DiagID);
break;
case tok::kw_int:
DS.SetTypeSpecType(DeclSpec::TST_int, Loc, PrevSpec, DiagID);
break;
case tok::kw_float:
DS.SetTypeSpecType(DeclSpec::TST_float, Loc, PrevSpec, DiagID);
break;
case tok::kw_double:
DS.SetTypeSpecType(DeclSpec::TST_double, Loc, PrevSpec, DiagID);
break;
case tok::kw_wchar_t:
DS.SetTypeSpecType(DeclSpec::TST_wchar, Loc, PrevSpec, DiagID);
break;
case tok::kw_char16_t:
DS.SetTypeSpecType(DeclSpec::TST_char16, Loc, PrevSpec, DiagID);
break;
case tok::kw_char32_t:
DS.SetTypeSpecType(DeclSpec::TST_char32, Loc, PrevSpec, DiagID);
break;
case tok::kw_bool:
DS.SetTypeSpecType(DeclSpec::TST_bool, Loc, PrevSpec, DiagID);
break;
// GNU typeof support.
case tok::kw_typeof:
ParseTypeofSpecifier(DS);
DS.Finish(Diags, PP);
return;
}
if (Tok.is(tok::annot_typename))
DS.SetRangeEnd(Tok.getAnnotationEndLoc());
else
DS.SetRangeEnd(Tok.getLocation());
ConsumeToken();
DS.Finish(Diags, PP);
}
/// ParseCXXTypeSpecifierSeq - Parse a C++ type-specifier-seq (C++
/// [dcl.name]), which is a non-empty sequence of type-specifiers,
/// e.g., "const short int". Note that the DeclSpec is *not* finished
/// by parsing the type-specifier-seq, because these sequences are
/// typically followed by some form of declarator. Returns true and
/// emits diagnostics if this is not a type-specifier-seq, false
/// otherwise.
///
/// type-specifier-seq: [C++ 8.1]
/// type-specifier type-specifier-seq[opt]
///
bool Parser::ParseCXXTypeSpecifierSeq(DeclSpec &DS) {
DS.SetRangeStart(Tok.getLocation());
const char *PrevSpec = 0;
unsigned DiagID;
bool isInvalid = 0;
// Parse one or more of the type specifiers.
if (!ParseOptionalTypeSpecifier(DS, isInvalid, PrevSpec, DiagID)) {
Diag(Tok, diag::err_operator_missing_type_specifier);
return true;
}
while (ParseOptionalTypeSpecifier(DS, isInvalid, PrevSpec, DiagID)) ;
return false;
}
/// TryParseOperatorFunctionId - Attempts to parse a C++ overloaded
/// operator name (C++ [over.oper]). If successful, returns the
/// predefined identifier that corresponds to that overloaded
/// operator. Otherwise, returns NULL and does not consume any tokens.
///
/// operator-function-id: [C++ 13.5]
/// 'operator' operator
///
/// operator: one of
/// new delete new[] delete[]
/// + - * / % ^ & | ~
/// ! = < > += -= *= /= %=
/// ^= &= |= << >> >>= <<= == !=
/// <= >= && || ++ -- , ->* ->
/// () []
OverloadedOperatorKind
Parser::TryParseOperatorFunctionId(SourceLocation *EndLoc) {
assert(Tok.is(tok::kw_operator) && "Expected 'operator' keyword");
SourceLocation Loc;
OverloadedOperatorKind Op = OO_None;
switch (NextToken().getKind()) {
case tok::kw_new:
ConsumeToken(); // 'operator'
Loc = ConsumeToken(); // 'new'
if (Tok.is(tok::l_square)) {
ConsumeBracket(); // '['
Loc = Tok.getLocation();
ExpectAndConsume(tok::r_square, diag::err_expected_rsquare); // ']'
Op = OO_Array_New;
} else {
Op = OO_New;
}
if (EndLoc)
*EndLoc = Loc;
return Op;
case tok::kw_delete:
ConsumeToken(); // 'operator'
Loc = ConsumeToken(); // 'delete'
if (Tok.is(tok::l_square)) {
ConsumeBracket(); // '['
Loc = Tok.getLocation();
ExpectAndConsume(tok::r_square, diag::err_expected_rsquare); // ']'
Op = OO_Array_Delete;
} else {
Op = OO_Delete;
}
if (EndLoc)
*EndLoc = Loc;
return Op;
#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \
case tok::Token: Op = OO_##Name; break;
#define OVERLOADED_OPERATOR_MULTI(Name,Spelling,Unary,Binary,MemberOnly)
#include "clang/Basic/OperatorKinds.def"
case tok::l_paren:
ConsumeToken(); // 'operator'
ConsumeParen(); // '('
Loc = Tok.getLocation();
ExpectAndConsume(tok::r_paren, diag::err_expected_rparen); // ')'
if (EndLoc)
*EndLoc = Loc;
return OO_Call;
case tok::l_square:
ConsumeToken(); // 'operator'
ConsumeBracket(); // '['
Loc = Tok.getLocation();
ExpectAndConsume(tok::r_square, diag::err_expected_rsquare); // ']'
if (EndLoc)
*EndLoc = Loc;
return OO_Subscript;
case tok::code_completion: {
// Code completion for the operator name.
Actions.CodeCompleteOperatorName(CurScope);
// Consume the 'operator' token, then replace the code-completion token
// with an 'operator' token and try again.
SourceLocation OperatorLoc = ConsumeToken();
Tok.setLocation(OperatorLoc);
Tok.setKind(tok::kw_operator);
return TryParseOperatorFunctionId(EndLoc);
}
default:
return OO_None;
}
ConsumeToken(); // 'operator'
Loc = ConsumeAnyToken(); // the operator itself
if (EndLoc)
*EndLoc = Loc;
return Op;
}
/// ParseConversionFunctionId - Parse a C++ conversion-function-id,
/// which expresses the name of a user-defined conversion operator
/// (C++ [class.conv.fct]p1). Returns the type that this operator is
/// specifying a conversion for, or NULL if there was an error.
///
/// conversion-function-id: [C++ 12.3.2]
/// operator conversion-type-id
///
/// conversion-type-id:
/// type-specifier-seq conversion-declarator[opt]
///
/// conversion-declarator:
/// ptr-operator conversion-declarator[opt]
Parser::TypeTy *Parser::ParseConversionFunctionId(SourceLocation *EndLoc) {
assert(Tok.is(tok::kw_operator) && "Expected 'operator' keyword");
ConsumeToken(); // 'operator'
// Parse the type-specifier-seq.
DeclSpec DS;
if (ParseCXXTypeSpecifierSeq(DS))
return 0;
// Parse the conversion-declarator, which is merely a sequence of
// ptr-operators.
Declarator D(DS, Declarator::TypeNameContext);
ParseDeclaratorInternal(D, /*DirectDeclParser=*/0);
if (EndLoc)
*EndLoc = D.getSourceRange().getEnd();
// Finish up the type.
Action::TypeResult Result = Actions.ActOnTypeName(CurScope, D);
if (Result.isInvalid())
return 0;
else
return Result.get();
}
/// ParseCXXNewExpression - Parse a C++ new-expression. New is used to allocate
/// memory in a typesafe manner and call constructors.
///
/// This method is called to parse the new expression after the optional :: has
/// been already parsed. If the :: was present, "UseGlobal" is true and "Start"
/// is its location. Otherwise, "Start" is the location of the 'new' token.
///
/// new-expression:
/// '::'[opt] 'new' new-placement[opt] new-type-id
/// new-initializer[opt]
/// '::'[opt] 'new' new-placement[opt] '(' type-id ')'
/// new-initializer[opt]
///
/// new-placement:
/// '(' expression-list ')'
///
/// new-type-id:
/// type-specifier-seq new-declarator[opt]
///
/// new-declarator:
/// ptr-operator new-declarator[opt]
/// direct-new-declarator
///
/// new-initializer:
/// '(' expression-list[opt] ')'
/// [C++0x] braced-init-list [TODO]
///
Parser::OwningExprResult
Parser::ParseCXXNewExpression(bool UseGlobal, SourceLocation Start) {
assert(Tok.is(tok::kw_new) && "expected 'new' token");
ConsumeToken(); // Consume 'new'
// A '(' now can be a new-placement or the '(' wrapping the type-id in the
// second form of new-expression. It can't be a new-type-id.
ExprVector PlacementArgs(Actions);
SourceLocation PlacementLParen, PlacementRParen;
bool ParenTypeId;
DeclSpec DS;
Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
if (Tok.is(tok::l_paren)) {
// If it turns out to be a placement, we change the type location.
PlacementLParen = ConsumeParen();
if (ParseExpressionListOrTypeId(PlacementArgs, DeclaratorInfo)) {
SkipUntil(tok::semi, /*StopAtSemi=*/true, /*DontConsume=*/true);
return ExprError();
}
PlacementRParen = MatchRHSPunctuation(tok::r_paren, PlacementLParen);
if (PlacementRParen.isInvalid()) {
SkipUntil(tok::semi, /*StopAtSemi=*/true, /*DontConsume=*/true);
return ExprError();
}
if (PlacementArgs.empty()) {
// Reset the placement locations. There was no placement.
PlacementLParen = PlacementRParen = SourceLocation();
ParenTypeId = true;
} else {
// We still need the type.
if (Tok.is(tok::l_paren)) {
SourceLocation LParen = ConsumeParen();
ParseSpecifierQualifierList(DS);
DeclaratorInfo.SetSourceRange(DS.getSourceRange());
ParseDeclarator(DeclaratorInfo);
MatchRHSPunctuation(tok::r_paren, LParen);
ParenTypeId = true;
} else {
if (ParseCXXTypeSpecifierSeq(DS))
DeclaratorInfo.setInvalidType(true);
else {
DeclaratorInfo.SetSourceRange(DS.getSourceRange());
ParseDeclaratorInternal(DeclaratorInfo,
&Parser::ParseDirectNewDeclarator);
}
ParenTypeId = false;
}
}
} else {
// A new-type-id is a simplified type-id, where essentially the
// direct-declarator is replaced by a direct-new-declarator.
if (ParseCXXTypeSpecifierSeq(DS))
DeclaratorInfo.setInvalidType(true);
else {
DeclaratorInfo.SetSourceRange(DS.getSourceRange());
ParseDeclaratorInternal(DeclaratorInfo,
&Parser::ParseDirectNewDeclarator);
}
ParenTypeId = false;
}
if (DeclaratorInfo.isInvalidType()) {
SkipUntil(tok::semi, /*StopAtSemi=*/true, /*DontConsume=*/true);
return ExprError();
}
ExprVector ConstructorArgs(Actions);
SourceLocation ConstructorLParen, ConstructorRParen;
if (Tok.is(tok::l_paren)) {
ConstructorLParen = ConsumeParen();
if (Tok.isNot(tok::r_paren)) {
CommaLocsTy CommaLocs;
if (ParseExpressionList(ConstructorArgs, CommaLocs)) {
SkipUntil(tok::semi, /*StopAtSemi=*/true, /*DontConsume=*/true);
return ExprError();
}
}
ConstructorRParen = MatchRHSPunctuation(tok::r_paren, ConstructorLParen);
if (ConstructorRParen.isInvalid()) {
SkipUntil(tok::semi, /*StopAtSemi=*/true, /*DontConsume=*/true);
return ExprError();
}
}
return Actions.ActOnCXXNew(Start, UseGlobal, PlacementLParen,
move_arg(PlacementArgs), PlacementRParen,
ParenTypeId, DeclaratorInfo, ConstructorLParen,
move_arg(ConstructorArgs), ConstructorRParen);
}
/// ParseDirectNewDeclarator - Parses a direct-new-declarator. Intended to be
/// passed to ParseDeclaratorInternal.
///
/// direct-new-declarator:
/// '[' expression ']'
/// direct-new-declarator '[' constant-expression ']'
///
void Parser::ParseDirectNewDeclarator(Declarator &D) {
// Parse the array dimensions.
bool first = true;
while (Tok.is(tok::l_square)) {
SourceLocation LLoc = ConsumeBracket();
OwningExprResult Size(first ? ParseExpression()
: ParseConstantExpression());
if (Size.isInvalid()) {
// Recover
SkipUntil(tok::r_square);
return;
}
first = false;
SourceLocation RLoc = MatchRHSPunctuation(tok::r_square, LLoc);
D.AddTypeInfo(DeclaratorChunk::getArray(0, /*static=*/false, /*star=*/false,
Size.release(), LLoc, RLoc),
RLoc);
if (RLoc.isInvalid())
return;
}
}
/// ParseExpressionListOrTypeId - Parse either an expression-list or a type-id.
/// This ambiguity appears in the syntax of the C++ new operator.
///
/// new-expression:
/// '::'[opt] 'new' new-placement[opt] '(' type-id ')'
/// new-initializer[opt]
///
/// new-placement:
/// '(' expression-list ')'
///
bool Parser::ParseExpressionListOrTypeId(ExprListTy &PlacementArgs,
Declarator &D) {
// The '(' was already consumed.
if (isTypeIdInParens()) {
ParseSpecifierQualifierList(D.getMutableDeclSpec());
D.SetSourceRange(D.getDeclSpec().getSourceRange());
ParseDeclarator(D);
return D.isInvalidType();
}
// It's not a type, it has to be an expression list.
// Discard the comma locations - ActOnCXXNew has enough parameters.
CommaLocsTy CommaLocs;
return ParseExpressionList(PlacementArgs, CommaLocs);
}
/// ParseCXXDeleteExpression - Parse a C++ delete-expression. Delete is used
/// to free memory allocated by new.
///
/// This method is called to parse the 'delete' expression after the optional
/// '::' has been already parsed. If the '::' was present, "UseGlobal" is true
/// and "Start" is its location. Otherwise, "Start" is the location of the
/// 'delete' token.
///
/// delete-expression:
/// '::'[opt] 'delete' cast-expression
/// '::'[opt] 'delete' '[' ']' cast-expression
Parser::OwningExprResult
Parser::ParseCXXDeleteExpression(bool UseGlobal, SourceLocation Start) {
assert(Tok.is(tok::kw_delete) && "Expected 'delete' keyword");
ConsumeToken(); // Consume 'delete'
// Array delete?
bool ArrayDelete = false;
if (Tok.is(tok::l_square)) {
ArrayDelete = true;
SourceLocation LHS = ConsumeBracket();
SourceLocation RHS = MatchRHSPunctuation(tok::r_square, LHS);
if (RHS.isInvalid())
return ExprError();
}
OwningExprResult Operand(ParseCastExpression(false));
if (Operand.isInvalid())
return move(Operand);
return Actions.ActOnCXXDelete(Start, UseGlobal, ArrayDelete, move(Operand));
}
static UnaryTypeTrait UnaryTypeTraitFromTokKind(tok::TokenKind kind) {
switch(kind) {
default: assert(false && "Not a known unary type trait.");
case tok::kw___has_nothrow_assign: return UTT_HasNothrowAssign;
case tok::kw___has_nothrow_copy: return UTT_HasNothrowCopy;
case tok::kw___has_nothrow_constructor: return UTT_HasNothrowConstructor;
case tok::kw___has_trivial_assign: return UTT_HasTrivialAssign;
case tok::kw___has_trivial_copy: return UTT_HasTrivialCopy;
case tok::kw___has_trivial_constructor: return UTT_HasTrivialConstructor;
case tok::kw___has_trivial_destructor: return UTT_HasTrivialDestructor;
case tok::kw___has_virtual_destructor: return UTT_HasVirtualDestructor;
case tok::kw___is_abstract: return UTT_IsAbstract;
case tok::kw___is_class: return UTT_IsClass;
case tok::kw___is_empty: return UTT_IsEmpty;
case tok::kw___is_enum: return UTT_IsEnum;
case tok::kw___is_pod: return UTT_IsPOD;
case tok::kw___is_polymorphic: return UTT_IsPolymorphic;
case tok::kw___is_union: return UTT_IsUnion;
}
}
/// ParseUnaryTypeTrait - Parse the built-in unary type-trait
/// pseudo-functions that allow implementation of the TR1/C++0x type traits
/// templates.
///
/// primary-expression:
/// [GNU] unary-type-trait '(' type-id ')'
///
Parser::OwningExprResult Parser::ParseUnaryTypeTrait() {
UnaryTypeTrait UTT = UnaryTypeTraitFromTokKind(Tok.getKind());
SourceLocation Loc = ConsumeToken();
SourceLocation LParen = Tok.getLocation();
if (ExpectAndConsume(tok::l_paren, diag::err_expected_lparen))
return ExprError();
// FIXME: Error reporting absolutely sucks! If the this fails to parse a type
// there will be cryptic errors about mismatched parentheses and missing
// specifiers.
TypeResult Ty = ParseTypeName();
SourceLocation RParen = MatchRHSPunctuation(tok::r_paren, LParen);
if (Ty.isInvalid())
return ExprError();
return Actions.ActOnUnaryTypeTrait(UTT, Loc, LParen, Ty.get(), RParen);
}
/// ParseCXXAmbiguousParenExpression - We have parsed the left paren of a
/// parenthesized ambiguous type-id. This uses tentative parsing to disambiguate
/// based on the context past the parens.
Parser::OwningExprResult
Parser::ParseCXXAmbiguousParenExpression(ParenParseOption &ExprType,
TypeTy *&CastTy,
SourceLocation LParenLoc,
SourceLocation &RParenLoc) {
assert(getLang().CPlusPlus && "Should only be called for C++!");
assert(ExprType == CastExpr && "Compound literals are not ambiguous!");
assert(isTypeIdInParens() && "Not a type-id!");
OwningExprResult Result(Actions, true);
CastTy = 0;
// We need to disambiguate a very ugly part of the C++ syntax:
//
// (T())x; - type-id
// (T())*x; - type-id
// (T())/x; - expression
// (T()); - expression
//
// The bad news is that we cannot use the specialized tentative parser, since
// it can only verify that the thing inside the parens can be parsed as
// type-id, it is not useful for determining the context past the parens.
//
// The good news is that the parser can disambiguate this part without
// making any unnecessary Action calls.
//
// It uses a scheme similar to parsing inline methods. The parenthesized
// tokens are cached, the context that follows is determined (possibly by
// parsing a cast-expression), and then we re-introduce the cached tokens
// into the token stream and parse them appropriately.
ParenParseOption ParseAs;
CachedTokens Toks;
// Store the tokens of the parentheses. We will parse them after we determine
// the context that follows them.
if (!ConsumeAndStoreUntil(tok::r_paren, tok::unknown, Toks, tok::semi)) {
// We didn't find the ')' we expected.
MatchRHSPunctuation(tok::r_paren, LParenLoc);
return ExprError();
}
if (Tok.is(tok::l_brace)) {
ParseAs = CompoundLiteral;
} else {
bool NotCastExpr;
// FIXME: Special-case ++ and --: "(S())++;" is not a cast-expression
if (Tok.is(tok::l_paren) && NextToken().is(tok::r_paren)) {
NotCastExpr = true;
} else {
// Try parsing the cast-expression that may follow.
// If it is not a cast-expression, NotCastExpr will be true and no token
// will be consumed.
Result = ParseCastExpression(false/*isUnaryExpression*/,
false/*isAddressofOperand*/,
NotCastExpr, false);
}
// If we parsed a cast-expression, it's really a type-id, otherwise it's
// an expression.
ParseAs = NotCastExpr ? SimpleExpr : CastExpr;
}
// The current token should go after the cached tokens.
Toks.push_back(Tok);
// Re-enter the stored parenthesized tokens into the token stream, so we may
// parse them now.
PP.EnterTokenStream(Toks.data(), Toks.size(),
true/*DisableMacroExpansion*/, false/*OwnsTokens*/);
// Drop the current token and bring the first cached one. It's the same token
// as when we entered this function.
ConsumeAnyToken();
if (ParseAs >= CompoundLiteral) {
TypeResult Ty = ParseTypeName();
// Match the ')'.
if (Tok.is(tok::r_paren))
RParenLoc = ConsumeParen();
else
MatchRHSPunctuation(tok::r_paren, LParenLoc);
if (ParseAs == CompoundLiteral) {
ExprType = CompoundLiteral;
return ParseCompoundLiteralExpression(Ty.get(), LParenLoc, RParenLoc);
}
// We parsed '(' type-id ')' and the thing after it wasn't a '{'.
assert(ParseAs == CastExpr);
if (Ty.isInvalid())
return ExprError();
CastTy = Ty.get();
// Result is what ParseCastExpression returned earlier.
if (!Result.isInvalid())
Result = Actions.ActOnCastExpr(CurScope, LParenLoc, CastTy, RParenLoc,
move(Result));
return move(Result);
}
// Not a compound literal, and not followed by a cast-expression.
assert(ParseAs == SimpleExpr);
ExprType = SimpleExpr;
Result = ParseExpression();
if (!Result.isInvalid() && Tok.is(tok::r_paren))
Result = Actions.ActOnParenExpr(LParenLoc, Tok.getLocation(), move(Result));
// Match the ')'.
if (Result.isInvalid()) {
SkipUntil(tok::r_paren);
return ExprError();
}
if (Tok.is(tok::r_paren))
RParenLoc = ConsumeParen();
else
MatchRHSPunctuation(tok::r_paren, LParenLoc);
return move(Result);
}