Unrevert r166268, reverted in r166272, with a fix for the issue which Nick

found: if an overloaded operator& is present before a template definition,
the expression &T::foo is represented as a CXXOperatorCallExpr, not as a
UnaryOperator, so we didn't notice that it's permitted to reference a non-static
data member of an unrelated class.

While investigating this, I discovered another problem in this area: we are
treating template default arguments as unevaluated contexts during substitution,
resulting in performing incorrect checks for uses of non-static data members in
C++11. That is not fixed by this patch (I'll look into this soon; it's related
to the failure to correctly instantiate constexpr function templates), but was
resulting in this bug not firing in C++11 mode (except with -Wc++98-compat).

Original message:

PR14124: When performing template instantiation of a qualified-id outside of a
class, diagnose if the qualified-id instantiates to a non-static class member.

llvm-svn: 166385
This commit is contained in:
Richard Smith 2012-10-21 03:28:35 +00:00
parent 7e1084d36c
commit db2630fb04
6 changed files with 76 additions and 18 deletions

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@ -2911,7 +2911,8 @@ public:
bool HasTrailingLParen);
ExprResult BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS,
const DeclarationNameInfo &NameInfo);
const DeclarationNameInfo &NameInfo,
bool IsAddressOfOperand);
ExprResult BuildDependentDeclRefExpr(const CXXScopeSpec &SS,
SourceLocation TemplateKWLoc,
const DeclarationNameInfo &NameInfo,

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@ -1895,7 +1895,8 @@ ExprResult Sema::ActOnIdExpression(Scope *S,
/// this path.
ExprResult
Sema::BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS,
const DeclarationNameInfo &NameInfo) {
const DeclarationNameInfo &NameInfo,
bool IsAddressOfOperand) {
DeclContext *DC;
if (!(DC = computeDeclContext(SS, false)) || DC->isDependentContext())
return BuildDependentDeclRefExpr(SS, /*TemplateKWLoc=*/SourceLocation(),
@ -1916,7 +1917,16 @@ Sema::BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS,
return ExprError();
}
return BuildDeclarationNameExpr(SS, R, /*ADL*/ false);
// Defend against this resolving to an implicit member access. We usually
// won't get here if this might be a legitimate a class member (we end up in
// BuildMemberReferenceExpr instead), but this can be valid if we're forming
// a pointer-to-member or in an unevaluated context in C++11.
if (!R.empty() && (*R.begin())->isCXXClassMember() && !IsAddressOfOperand)
return BuildPossibleImplicitMemberExpr(SS,
/*TemplateKWLoc=*/SourceLocation(),
R, /*TemplateArgs=*/0);
return BuildDeclarationNameExpr(SS, R, /* ADL */ false);
}
/// LookupInObjCMethod - The parser has read a name in, and Sema has

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@ -574,6 +574,10 @@ public:
/// \brief Transform the captures and body of a lambda expression.
ExprResult TransformLambdaScope(LambdaExpr *E, CXXMethodDecl *CallOperator);
ExprResult TransformAddressOfOperand(Expr *E);
ExprResult TransformDependentScopeDeclRefExpr(DependentScopeDeclRefExpr *E,
bool IsAddressOfOperand);
#define STMT(Node, Parent) \
StmtResult Transform##Node(Node *S);
#define EXPR(Node, Parent) \
@ -2073,7 +2077,8 @@ public:
NestedNameSpecifierLoc QualifierLoc,
SourceLocation TemplateKWLoc,
const DeclarationNameInfo &NameInfo,
const TemplateArgumentListInfo *TemplateArgs) {
const TemplateArgumentListInfo *TemplateArgs,
bool IsAddressOfOperand) {
CXXScopeSpec SS;
SS.Adopt(QualifierLoc);
@ -2081,7 +2086,8 @@ public:
return getSema().BuildQualifiedTemplateIdExpr(SS, TemplateKWLoc,
NameInfo, TemplateArgs);
return getSema().BuildQualifiedDeclarationNameExpr(SS, NameInfo);
return getSema().BuildQualifiedDeclarationNameExpr(SS, NameInfo,
IsAddressOfOperand);
}
/// \brief Build a new template-id expression.
@ -6138,10 +6144,22 @@ TreeTransform<Derived>::TransformParenExpr(ParenExpr *E) {
E->getRParen());
}
/// \brief The operand of a unary address-of operator has special rules: it's
/// allowed to refer to a non-static member of a class even if there's no 'this'
/// object available.
template<typename Derived>
ExprResult
TreeTransform<Derived>::TransformAddressOfOperand(Expr *E) {
if (DependentScopeDeclRefExpr *DRE = dyn_cast<DependentScopeDeclRefExpr>(E))
return getDerived().TransformDependentScopeDeclRefExpr(DRE, true);
else
return getDerived().TransformExpr(E);
}
template<typename Derived>
ExprResult
TreeTransform<Derived>::TransformUnaryOperator(UnaryOperator *E) {
ExprResult SubExpr = getDerived().TransformExpr(E->getSubExpr());
ExprResult SubExpr = TransformAddressOfOperand(E->getSubExpr());
if (SubExpr.isInvalid())
return ExprError();
@ -6842,7 +6860,11 @@ TreeTransform<Derived>::TransformCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
if (Callee.isInvalid())
return ExprError();
ExprResult First = getDerived().TransformExpr(E->getArg(0));
ExprResult First;
if (E->getOperator() == OO_Amp)
First = getDerived().TransformAddressOfOperand(E->getArg(0));
else
First = getDerived().TransformExpr(E->getArg(0));
if (First.isInvalid())
return ExprError();
@ -7671,6 +7693,14 @@ template<typename Derived>
ExprResult
TreeTransform<Derived>::TransformDependentScopeDeclRefExpr(
DependentScopeDeclRefExpr *E) {
return TransformDependentScopeDeclRefExpr(E, /*IsAddressOfOperand*/false);
}
template<typename Derived>
ExprResult
TreeTransform<Derived>::TransformDependentScopeDeclRefExpr(
DependentScopeDeclRefExpr *E,
bool IsAddressOfOperand) {
NestedNameSpecifierLoc QualifierLoc
= getDerived().TransformNestedNameSpecifierLoc(E->getQualifierLoc());
if (!QualifierLoc)
@ -7697,7 +7727,8 @@ TreeTransform<Derived>::TransformDependentScopeDeclRefExpr(
return getDerived().RebuildDependentScopeDeclRefExpr(QualifierLoc,
TemplateKWLoc,
NameInfo,
/*TemplateArgs*/ 0);
/*TemplateArgs*/ 0,
IsAddressOfOperand);
}
TemplateArgumentListInfo TransArgs(E->getLAngleLoc(), E->getRAngleLoc());
@ -7709,7 +7740,8 @@ TreeTransform<Derived>::TransformDependentScopeDeclRefExpr(
return getDerived().RebuildDependentScopeDeclRefExpr(QualifierLoc,
TemplateKWLoc,
NameInfo,
&TransArgs);
&TransArgs,
IsAddressOfOperand);
}
template<typename Derived>

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@ -1,16 +1,16 @@
// RUN: %clang_cc1 -fsyntax-only -verify %s -std=c++11
void f(); // expected-note{{possible target for call}}
void f(int); // expected-note{{possible target for call}}
void f(); // expected-note{{possible target for call}}
void f(int); // expected-note{{possible target for call}}
decltype(f) a; // expected-error{{reference to overloaded function could not be resolved; did you mean to call it with no arguments?}} expected-error {{variable has incomplete type 'decltype(f())' (aka 'void')}}
template<typename T> struct S {
decltype(T::f) * f; // expected-error{{reference to overloaded function could not be resolved; did you mean to call it with no arguments?}} expected-error {{call to non-static member function without an object argument}}
decltype(T::f) * f; // expected-error {{call to non-static member function without an object argument}}
};
struct K {
void f(); // expected-note{{possible target for call}}
void f(int); // expected-note{{possible target for call}}
void f();
void f(int);
};
S<K> b; // expected-note{{in instantiation of template class 'S<K>' requested here}}

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@ -133,14 +133,14 @@ void test2() {
namespace rdar9027658 {
template <typename T>
void f() {
if ((T::g == 3)) { } // expected-warning {{equality comparison with extraneous parentheses}} \
void f(T t) {
if ((t.g == 3)) { } // expected-warning {{equality comparison with extraneous parentheses}} \
// expected-note {{use '=' to turn this equality comparison into an assignment}} \
// expected-note {{remove extraneous parentheses around the comparison to silence this warning}}
}
struct S { int g; };
void test() {
f<S>(); // expected-note {{in instantiation}}
f(S()); // expected-note {{in instantiation}}
}
}

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@ -1,4 +1,4 @@
// RUN: %clang_cc1 -fsyntax-only -verify %s
// RUN: %clang_cc1 -fsyntax-only -verify %s -pedantic
template<typename T>
struct S {
S() { }
@ -66,3 +66,18 @@ namespace test2 {
template class B<int>;
}
namespace PR14124 {
template<typename T> struct S {
int value;
};
template<typename T> void f() { S<T>::value; } // expected-error {{invalid use of non-static data member 'value'}}
template void f<int>(); // expected-note {{in instantiation of}}
struct List { List *next; };
template<typename T, T *(T::*p) = &T::next> struct A {};
A<List> a; // ok
void operator&(struct Whatever);
template<typename T, T *(T::*p) = &T::next> struct B {};
B<List> b; // still ok
}