Files
clang-p2996/clang/test/SemaTemplate/dependent-names.cpp
Matheus Izvekov 15f3cd6bfc [clang] Implement ElaboratedType sugaring for types written bare
Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which goes against the intent that
we should produce an AST which retains enough details to recover how things are
written.

The lack of this sugar is incompatible with the intent of the type printer
default policy, which is to print types as written, but to fall back and print
them fully qualified when they are desugared.

An ElaboratedTypeLoc without keyword / NNS uses no storage by itself, but still
requires pointer alignment due to pre-existing bug in the TypeLoc buffer
handling.

---

Troubleshooting list to deal with any breakage seen with this patch:

1) The most likely effect one would see by this patch is a change in how
   a type is printed. The type printer will, by design and default,
   print types as written. There are customization options there, but
   not that many, and they mainly apply to how to print a type that we
   somehow failed to track how it was written. This patch fixes a
   problem where we failed to distinguish between a type
   that was written without any elaborated-type qualifiers,
   such as a 'struct'/'class' tags and name spacifiers such as 'std::',
   and one that has been stripped of any 'metadata' that identifies such,
   the so called canonical types.
   Example:
   ```
   namespace foo {
     struct A {};
     A a;
   };
   ```
   If one were to print the type of `foo::a`, prior to this patch, this
   would result in `foo::A`. This is how the type printer would have,
   by default, printed the canonical type of A as well.
   As soon as you add any name qualifiers to A, the type printer would
   suddenly start accurately printing the type as written. This patch
   will make it print it accurately even when written without
   qualifiers, so we will just print `A` for the initial example, as
   the user did not really write that `foo::` namespace qualifier.

2) This patch could expose a bug in some AST matcher. Matching types
   is harder to get right when there is sugar involved. For example,
   if you want to match a type against being a pointer to some type A,
   then you have to account for getting a type that is sugar for a
   pointer to A, or being a pointer to sugar to A, or both! Usually
   you would get the second part wrong, and this would work for a
   very simple test where you don't use any name qualifiers, but
   you would discover is broken when you do. The usual fix is to
   either use the matcher which strips sugar, which is annoying
   to use as for example if you match an N level pointer, you have
   to put N+1 such matchers in there, beginning to end and between
   all those levels. But in a lot of cases, if the property you want
   to match is present in the canonical type, it's easier and faster
   to just match on that... This goes with what is said in 1), if
   you want to match against the name of a type, and you want
   the name string to be something stable, perhaps matching on
   the name of the canonical type is the better choice.

3) This patch could expose a bug in how you get the source range of some
   TypeLoc. For some reason, a lot of code is using getLocalSourceRange(),
   which only looks at the given TypeLoc node. This patch introduces a new,
   and more common TypeLoc node which contains no source locations on itself.
   This is not an inovation here, and some other, more rare TypeLoc nodes could
   also have this property, but if you use getLocalSourceRange on them, it's not
   going to return any valid locations, because it doesn't have any. The right fix
   here is to always use getSourceRange() or getBeginLoc/getEndLoc which will dive
   into the inner TypeLoc to get the source range if it doesn't find it on the
   top level one. You can use getLocalSourceRange if you are really into
   micro-optimizations and you have some outside knowledge that the TypeLocs you are
   dealing with will always include some source location.

4) Exposed a bug somewhere in the use of the normal clang type class API, where you
   have some type, you want to see if that type is some particular kind, you try a
   `dyn_cast` such as `dyn_cast<TypedefType>` and that fails because now you have an
   ElaboratedType which has a TypeDefType inside of it, which is what you wanted to match.
   Again, like 2), this would usually have been tested poorly with some simple tests with
   no qualifications, and would have been broken had there been any other kind of type sugar,
   be it an ElaboratedType or a TemplateSpecializationType or a SubstTemplateParmType.
   The usual fix here is to use `getAs` instead of `dyn_cast`, which will look deeper
   into the type. Or use `getAsAdjusted` when dealing with TypeLocs.
   For some reason the API is inconsistent there and on TypeLocs getAs behaves like a dyn_cast.

5) It could be a bug in this patch perhaps.

Let me know if you need any help!

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Differential Revision: https://reviews.llvm.org/D112374
2022-07-27 11:10:54 +02:00

459 lines
13 KiB
C++

// RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 %s
typedef double A;
template<typename T> class B {
typedef int A;
};
template<typename T> struct X : B<T> {
static A a;
};
int a0[sizeof(X<int>::a) == sizeof(double) ? 1 : -1];
// PR4365.
template<class T> class Q;
template<class T> class R : Q<T> {T current;};
namespace test0 {
template <class T> class Base {
public:
void instance_foo();
static void static_foo();
class Inner {
public:
void instance_foo();
static void static_foo();
};
};
template <class T> class Derived1 : Base<T> {
public:
void test0() {
Base<T>::static_foo();
Base<T>::instance_foo();
}
void test1() {
Base<T>::Inner::static_foo();
Base<T>::Inner::instance_foo(); // expected-error {{call to non-static member function without an object argument}}
}
static void test2() {
Base<T>::static_foo();
Base<T>::instance_foo(); // expected-error {{call to non-static member function without an object argument}}
}
static void test3() {
Base<T>::Inner::static_foo();
Base<T>::Inner::instance_foo(); // expected-error {{call to non-static member function without an object argument}}
}
};
template <class T> class Derived2 : Base<T>::Inner {
public:
void test0() {
Base<T>::static_foo();
Base<T>::instance_foo(); // expected-error {{call to non-static member function without an object argument}}
}
void test1() {
Base<T>::Inner::static_foo();
Base<T>::Inner::instance_foo();
}
static void test2() {
Base<T>::static_foo();
Base<T>::instance_foo(); // expected-error {{call to non-static member function without an object argument}}
}
static void test3() {
Base<T>::Inner::static_foo();
Base<T>::Inner::instance_foo(); // expected-error {{call to non-static member function without an object argument}}
}
};
void test0() {
Derived1<int> d1;
d1.test0();
d1.test1(); // expected-note {{in instantiation of member function}}
d1.test2(); // expected-note {{in instantiation of member function}}
d1.test3(); // expected-note {{in instantiation of member function}}
Derived2<int> d2;
d2.test0(); // expected-note {{in instantiation of member function}}
d2.test1();
d2.test2(); // expected-note {{in instantiation of member function}}
d2.test3(); // expected-note {{in instantiation of member function}}
}
}
namespace test1 {
template <class T> struct Base {
void foo(T); // expected-note {{member is declared here}}
};
template <class T> struct Derived : Base<T> {
void doFoo(T v) {
foo(v); // expected-error {{explicit qualification required to use member 'foo' from dependent base class}}
}
};
template struct Derived<int>; // expected-note {{requested here}}
}
namespace PR8966 {
template <class T>
class MyClassCore
{
};
template <class T>
class MyClass : public MyClassCore<T>
{
public:
enum {
N
};
// static member declaration
static const char* array [N];
void f() {
MyClass<T>::InBase = 17;
}
};
// static member definition
template <class T>
const char* MyClass<T>::array [MyClass<T>::N] = { "A", "B", "C" };
}
namespace std {
inline namespace v1 {
template<typename T> struct basic_ostream;
}
namespace inner {
template<typename T> struct vector {};
}
using inner::vector;
template<typename T, typename U> struct pair {};
typedef basic_ostream<char> ostream;
extern ostream cout;
std::ostream &operator<<(std::ostream &out, const char *);
}
namespace PR10053 {
template<typename T> struct A {
T t;
A() {
f(t); // expected-error {{call to function 'f' that is neither visible in the template definition nor found by argument-dependent lookup}}
}
};
void f(int&); // expected-note {{'f' should be declared prior to the call site}}
A<int> a; // expected-note {{in instantiation of member function}}
namespace N {
namespace M {
template<typename T> int g(T t) {
f(t); // expected-error {{call to function 'f' that is neither visible in the template definition nor found by argument-dependent lookup}}
};
}
void f(char&); // expected-note {{'f' should be declared prior to the call site}}
}
void f(char&);
int k = N::M::g<char>(0);; // expected-note {{in instantiation of function}}
namespace O {
int f(char&); // expected-note {{candidate function not viable}}
template<typename T> struct C {
static const int n = f(T()); // expected-error {{no matching function}}
};
}
int f(double); // no note, shadowed by O::f
O::C<double> c; // expected-note {{requested here}}
// Example from www/compatibility.html
namespace my_file {
template <typename T> T Squared(T x) {
return Multiply(x, x); // expected-error {{neither visible in the template definition nor found by argument-dependent lookup}}
}
int Multiply(int x, int y) { // expected-note {{should be declared prior to the call site}}
return x * y;
}
int main() {
Squared(5); // expected-note {{here}}
}
}
// Example from www/compatibility.html
namespace my_file2 {
template<typename T>
void Dump(const T& value) {
std::cout << value << "\n"; // expected-error {{neither visible in the template definition nor found by argument-dependent lookup}}
}
namespace ns {
struct Data {};
}
std::ostream& operator<<(std::ostream& out, ns::Data data) { // expected-note {{should be declared prior to the call site or in namespace 'PR10053::my_file2::ns'}}
return out << "Some data";
}
void Use() {
Dump(ns::Data()); // expected-note {{here}}
}
}
namespace my_file2_a {
template<typename T>
void Dump(const T &value) {
print(std::cout, value); // expected-error 4{{neither visible in the template definition nor found by argument-dependent lookup}}
}
namespace ns {
struct Data {};
}
namespace ns2 {
struct Data {};
}
std::ostream &print(std::ostream &out, int); // expected-note-re {{should be declared prior to the call site{{$}}}}
std::ostream &print(std::ostream &out, ns::Data); // expected-note {{should be declared prior to the call site or in namespace 'PR10053::my_file2_a::ns'}}
std::ostream &print(std::ostream &out, std::vector<ns2::Data>); // expected-note {{should be declared prior to the call site or in namespace 'PR10053::my_file2_a::ns2'}}
std::ostream &print(std::ostream &out, std::pair<ns::Data, ns2::Data>); // expected-note {{should be declared prior to the call site or in an associated namespace of one of its arguments}}
void Use() {
Dump(0); // expected-note {{requested here}}
Dump(ns::Data()); // expected-note {{requested here}}
Dump(std::vector<ns2::Data>()); // expected-note {{requested here}}
Dump(std::pair<ns::Data, ns2::Data>()); // expected-note {{requested here}}
}
}
namespace unary {
template<typename T>
T Negate(const T& value) {
return !value; // expected-error {{call to function 'operator!' that is neither visible in the template definition nor found by argument-dependent lookup}}
}
namespace ns {
struct Data {};
}
ns::Data operator!(ns::Data); // expected-note {{should be declared prior to the call site or in namespace 'PR10053::unary::ns'}}
void Use() {
Negate(ns::Data()); // expected-note {{requested here}}
}
}
}
namespace PR10187 {
namespace A1 {
template<typename T>
struct S {
void f() {
for (auto &a : e)
__range(a); // expected-error {{undeclared identifier '__range'}}
}
int e[10];
};
}
namespace A2 {
template<typename T>
struct S {
void f() {
for (auto &a : e)
__range(a); // expected-error {{undeclared identifier '__range'}}
}
T e[10];
};
void g() {
S<int>().f(); // expected-note {{here}}
}
struct X {};
void __range(X);
void h() {
S<X>().f();
}
}
namespace B {
template<typename T> void g(); // expected-note {{not viable}}
template<typename T> void f() {
g<int>(T()); // expected-error {{no matching function}}
}
namespace {
struct S {};
}
void g(S);
template void f<S>(); // expected-note {{here}}
}
}
namespace rdar11242625 {
template <typename T>
struct Main {
struct default_names {
typedef int id;
};
template <typename T2 = typename default_names::id>
struct TS {
T2 q;
};
};
struct Sub : public Main<int> {
TS<> ff;
};
int arr[sizeof(Sub)];
}
namespace PR11421 {
template < unsigned > struct X {
static const unsigned dimension = 3;
template<unsigned dim=dimension>
struct Y: Y<dim> { }; // expected-error{{circular inheritance between 'Y<dim>' and 'Y<dim>'}}
};
typedef X<3> X3;
X3::Y<>::iterator it; // expected-error {{no type named 'iterator' in 'PR11421::X<3>::Y<3>'}}
}
namespace rdar12629723 {
template<class T>
struct X {
struct C : public C { }; // expected-error{{circular inheritance between 'C' and 'rdar12629723::X::C'}}
struct B;
struct A : public B { // expected-note{{'A' declared here}}
virtual void foo() { }
};
struct D : T::foo { };
struct E : D { };
};
template<class T>
struct X<T>::B : public A { // expected-error{{circular inheritance between 'A' and 'rdar12629723::X::B'}}
virtual void foo() { }
};
}
namespace test_reserved_identifiers {
template<typename A, typename B> void tempf(A a, B b) {
a + b; // expected-error{{call to function 'operator+' that is neither visible in the template definition nor found by argument-dependent lookup}}
}
namespace __gnu_cxx { struct X {}; }
namespace ns { struct Y {}; }
void operator+(__gnu_cxx::X, ns::Y); // expected-note{{or in namespace 'test_reserved_identifiers::ns'}}
void test() {
__gnu_cxx::X x;
ns::Y y;
tempf(x, y); // expected-note{{in instantiation of}}
}
}
// This test must live in the global namespace.
struct PR14695_X {};
// FIXME: This note is bogus; it is the using directive which would need to move
// to prior to the call site to fix the problem.
namespace PR14695_A { void PR14695_f(PR14695_X); } // expected-note {{'PR14695_f' should be declared prior to the call site or in the global namespace}}
template<typename T> void PR14695_g(T t) { PR14695_f(t); } // expected-error {{call to function 'PR14695_f' that is neither visible in the template definition nor found by argument-dependent lookup}}
using namespace PR14695_A;
template void PR14695_g(PR14695_X); // expected-note{{requested here}}
namespace OperatorNew {
template<typename T> void f(T t) {
operator new(100, t); // expected-error{{call to function 'operator new' that is neither visible in the template definition nor found by argument-dependent lookup}}
// FIXME: This should give the same error.
new (t) int;
}
struct X {};
};
using size_t = decltype(sizeof(0));
void *operator new(size_t, OperatorNew::X); // expected-note-re {{should be declared prior to the call site{{$}}}}
template void OperatorNew::f(OperatorNew::X); // expected-note {{instantiation of}}
namespace PR19936 {
template<typename T> decltype(*T()) f() {} // expected-note {{previous}}
template<typename T> decltype(T() * T()) g() {} // expected-note {{previous}}
// Create some overloaded operators so we build an overload operator call
// instead of a builtin operator call for the dependent expression.
enum E {};
int operator*(E);
int operator*(E, E);
// Check that they still profile the same.
template<typename T> decltype(*T()) f() {} // expected-error {{redefinition}}
template<typename T> decltype(T() * T()) g() {} // expected-error {{redefinition}}
}
template <typename> struct CT2 {
template <class U> struct X;
};
template <typename T> int CT2<int>::X<>; // expected-error {{template parameter list matching the non-templated nested type 'CT2<int>' should be empty}}
namespace DependentTemplateIdWithNoArgs {
template<typename T> void f() { T::template f(); }
struct X {
template<int = 0> static void f();
};
void g() { f<X>(); }
}
namespace DependentUnresolvedUsingTemplate {
template<typename T>
struct X : T {
using T::foo;
void f() { this->template foo(); } // expected-error {{does not refer to a template}}
void g() { this->template foo<>(); } // expected-error {{does not refer to a template}}
void h() { this->template foo<int>(); } // expected-error {{does not refer to a template}}
};
struct A { template<typename = int> int foo(); };
struct B { int foo(); }; // expected-note 3{{non-template here}}
void test(X<A> xa, X<B> xb) {
xa.f();
xa.g();
xa.h();
xb.f(); // expected-note {{instantiation of}}
xb.g(); // expected-note {{instantiation of}}
xb.h(); // expected-note {{instantiation of}}
}
}
namespace PR37680 {
template <class a> struct b : a {
using a::add;
template<int> int add() { return this->template add(0); }
};
struct a {
template<typename T = void> int add(...);
void add(int);
};
int f(b<a> ba) { return ba.add<0>(); }
}