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[Clang] Ensure "=default"ed function can be deleted when used as an extension in C++03 #90725

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[Clang] Ensure "=default"ed function can be deleted when used as an extension in C++03 #90725

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0793795
[Clang] Ensure "=default"ed function can be deleted when used as an e…
MitalAshok May 1, 2024
cb60e46
Change some tests' expected messages
MitalAshok May 1, 2024
383b460
Merge branch 'main' into fix-cxx03-defaulted-extension
MitalAshok May 1, 2024
5df6f72
Assert ShouldDeleteSpecialMember is called in C++ only
MitalAshok May 1, 2024
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13 changes: 11 additions & 2 deletions clang/lib/Sema/SemaDeclCXX.cpp
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Expand Up @@ -9763,13 +9763,22 @@ bool Sema::ShouldDeleteSpecialMember(CXXMethodDecl *MD,
CXXSpecialMemberKind CSM,
InheritedConstructorInfo *ICI,
bool Diagnose) {
assert(LangOpts.CPlusPlus &&
"Special member function = default outside of C++?");
if (MD->isInvalidDecl())
return false;
CXXRecordDecl *RD = MD->getParent();
assert(!RD->isDependentType() && "do deletion after instantiation");
if (!LangOpts.CPlusPlus || (!LangOpts.CPlusPlus11 && !RD->isLambda()) ||
RD->isInvalidDecl())
if (RD->isInvalidDecl())
return false;
if (!LangOpts.CPlusPlus11) {
// Before C++11, implicitly-declared (defaulted) special member functions
// weren't defined as deleted.
// Allow lambda members and explicitly defaulted members to be defined
// as deleted before C++11 as an extension
if (!(RD->isLambda() || MD->isExplicitlyDefaulted()))
return false;
}

// C++11 [expr.lambda.prim]p19:
// The closure type associated with a lambda-expression has a
Expand Down
70 changes: 20 additions & 50 deletions clang/test/CXX/drs/dr16xx.cpp
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Expand Up @@ -192,36 +192,24 @@ namespace cwg1658 { // cwg1658: 5
struct E : A { E(); virtual void foo() = 0; }; // #cwg1658-E1
E::E() = default; // #cwg1658-E1-ctor
// cxx98-error@-1 {{defaulted function definitions are a C++11 extension}}
// cxx98-error@-2 {{base class 'A' has private default constructor}}
// cxx98-note@-3 {{in defaulted default constructor for 'cwg1658::DefCtor::E' first required here}}
// cxx98-note@#cwg1658-A1 {{implicitly declared private here}}
// since-cxx11-error@#cwg1658-E1-ctor {{defaulting this default constructor would delete it after its first declaration}}
// since-cxx11-note@#cwg1658-E1 {{default constructor of 'E' is implicitly deleted because base class 'A' has an inaccessible default constructor}}
// expected-error@#cwg1658-E1-ctor {{defaulting this default constructor would delete it after its first declaration}}
// expected-note@#cwg1658-E1 {{default constructor of 'E' is implicitly deleted because base class 'A' has an inaccessible default constructor}}
struct F : virtual A { F(); }; // #cwg1658-F1
F::F() = default; // #cwg1658-F1-ctor
// cxx98-error@-1 {{defaulted function definitions are a C++11 extension}}
// cxx98-error@-2 {{inherited virtual base class 'A' has private default constructor}}
// cxx98-note@-3 {{in defaulted default constructor for 'cwg1658::DefCtor::F' first required here}}
// cxx98-note@#cwg1658-A1 {{implicitly declared private here}}
// since-cxx11-error@#cwg1658-F1-ctor {{defaulting this default constructor would delete it after its first declaration}}
// since-cxx11-note@#cwg1658-F1 {{default constructor of 'F' is implicitly deleted because base class 'A' has an inaccessible default constructor}}
// expected-error@#cwg1658-F1-ctor {{defaulting this default constructor would delete it after its first declaration}}
// expected-note@#cwg1658-F1 {{default constructor of 'F' is implicitly deleted because base class 'A' has an inaccessible default constructor}}

struct G : B { G(); virtual void foo() = 0; }; // #cwg1658-G1
G::G() = default; // #cwg1658-G1-ctor
// cxx98-error@-1 {{defaulted function definitions are a C++11 extension}}
// cxx98-error@#cwg1658-G1 {{base class 'B' has private destructor}}
// cxx98-note@#cwg1658-G1-ctor {{in defaulted default constructor for 'cwg1658::DefCtor::G' first required here}}
// cxx98-note@#cwg1658-B1 {{implicitly declared private here}}
// since-cxx11-error@#cwg1658-G1-ctor {{defaulting this default constructor would delete it after its first declaration}}
// since-cxx11-note@#cwg1658-G1 {{default constructor of 'G' is implicitly deleted because base class 'B' has an inaccessible destructor}}
// expected-error@#cwg1658-G1-ctor {{defaulting this default constructor would delete it after its first declaration}}
// expected-note@#cwg1658-G1 {{default constructor of 'G' is implicitly deleted because base class 'B' has an inaccessible destructor}}
struct H : virtual B { H(); }; // #cwg1658-H1
H::H() = default; // #cwg1658-H1-ctor
// cxx98-error@-1 {{defaulted function definitions are a C++11 extension}}
// cxx98-error@#cwg1658-H1 {{base class 'B' has private destructor}}
// cxx98-note@#cwg1658-H1-ctor {{in defaulted default constructor for 'cwg1658::DefCtor::H' first required here}}
// cxx98-note@#cwg1658-B1 {{implicitly declared private here}}
// since-cxx11-error@#cwg1658-H1-ctor {{defaulting this default constructor would delete it after its first declaration}}
// since-cxx11-note@#cwg1658-H1 {{default constructor of 'H' is implicitly deleted because base class 'B' has an inaccessible destructor}}
// expected-error@#cwg1658-H1-ctor {{defaulting this default constructor would delete it after its first declaration}}
// expected-note@#cwg1658-H1 {{default constructor of 'H' is implicitly deleted because base class 'B' has an inaccessible destructor}}
}

namespace Dtor {
Expand All @@ -234,19 +222,13 @@ namespace cwg1658 { // cwg1658: 5
struct G : B { ~G(); virtual void foo() = 0; }; // #cwg1658-G2
G::~G() = default; // #cwg1658-G2-dtor
// cxx98-error@-1 {{defaulted function definitions are a C++11 extension}}
// cxx98-error@#cwg1658-G2 {{base class 'B' has private destructor}}
// cxx98-note@#cwg1658-G2-dtor {{in defaulted destructor for 'cwg1658::Dtor::G' first required here}}
// cxx98-note@#cwg1658-B2 {{implicitly declared private here}}
// since-cxx11-error@#cwg1658-G2-dtor {{defaulting this destructor would delete it after its first declaration}}
// since-cxx11-note@#cwg1658-G2 {{destructor of 'G' is implicitly deleted because base class 'B' has an inaccessible destructor}}
// expected-error@#cwg1658-G2-dtor {{defaulting this destructor would delete it after its first declaration}}
// expected-note@#cwg1658-G2 {{destructor of 'G' is implicitly deleted because base class 'B' has an inaccessible destructor}}
struct H : virtual B { ~H(); }; // #cwg1658-H2
H::~H() = default; // #cwg1658-H2-dtor
// cxx98-error@-1 {{defaulted function definitions are a C++11 extension}}
// cxx98-error@#cwg1658-H2 {{base class 'B' has private destructor}}
// cxx98-note@#cwg1658-H2-dtor {{in defaulted destructor for 'cwg1658::Dtor::H' first required here}}
// cxx98-note@#cwg1658-B2 {{implicitly declared private here}}
// since-cxx11-error@#cwg1658-H2-dtor {{defaulting this destructor would delete it after its first declaration}}
// since-cxx11-note@#cwg1658-H2 {{destructor of 'H' is implicitly deleted because base class 'B' has an inaccessible destructor}}
// expected-error@#cwg1658-H2-dtor {{defaulting this destructor would delete it after its first declaration}}
// expected-note@#cwg1658-H2 {{destructor of 'H' is implicitly deleted because base class 'B' has an inaccessible destructor}}
}

namespace MemInit {
Expand Down Expand Up @@ -291,36 +273,24 @@ namespace cwg1658 { // cwg1658: 5
// cxx98-error@-1 {{rvalue references are a C++11 extension}}
E::E(const E&) = default; // #cwg1658-E5-copy-ctor
// cxx98-error@-1 {{defaulted function definitions are a C++11 extension}}
// cxx98-error@-2 {{base class 'A' has private copy constructor}}
// cxx98-note@-3 {{in defaulted copy constructor for 'cwg1658::CopyCtor::E' first required here}}
// cxx98-note@#cwg1658-A5 {{implicitly declared private here}}
// since-cxx11-error@#cwg1658-E5-copy-ctor {{defaulting this copy constructor would delete it after its first declaration}}
// since-cxx11-note@#cwg1658-E5 {{copy constructor of 'E' is implicitly deleted because base class 'A' has an inaccessible copy constructor}}
// expected-error@#cwg1658-E5-copy-ctor {{defaulting this copy constructor would delete it after its first declaration}}
// expected-note@#cwg1658-E5 {{copy constructor of 'E' is implicitly deleted because base class 'A' has an inaccessible copy constructor}}
E::E(E&&) = default; // #cwg1658-E5-move-ctor
// cxx98-error@-1 {{rvalue references are a C++11 extension}}
// cxx98-error@-2 {{defaulted function definitions are a C++11 extension}}
// cxx98-error@-3 {{base class 'A' has private move constructor}}
// cxx98-note@-4 {{in defaulted move constructor for 'cwg1658::CopyCtor::E' first required here}}
// cxx98-note@#cwg1658-A5 {{implicitly declared private here}}
// since-cxx11-error@#cwg1658-E5-move-ctor {{defaulting this move constructor would delete it after its first declaration}}
// since-cxx11-note@#cwg1658-E5 {{move constructor of 'E' is implicitly deleted because base class 'A' has an inaccessible move constructor}}
// expected-error@#cwg1658-E5-move-ctor {{defaulting this move constructor would delete it after its first declaration}}
// expected-note@#cwg1658-E5 {{move constructor of 'E' is implicitly deleted because base class 'A' has an inaccessible move constructor}}
struct F : virtual A { F(const F&); F(F&&); }; // #cwg1658-F5
// cxx98-error@-1 {{rvalue references are a C++11 extension}}
F::F(const F&) = default; // #cwg1658-F5-copy-ctor
// cxx98-error@-1 {{defaulted function definitions are a C++11 extension}}
// cxx98-error@-2 {{inherited virtual base class 'A' has private copy constructor}}
// cxx98-note@-3 {{in defaulted copy constructor for 'cwg1658::CopyCtor::F' first required here}}
// cxx98-note@#cwg1658-A5 {{implicitly declared private here}}
// since-cxx11-error@#cwg1658-F5-copy-ctor {{defaulting this copy constructor would delete it after its first declaration}}
// since-cxx11-note@#cwg1658-F5 {{copy constructor of 'F' is implicitly deleted because base class 'A' has an inaccessible copy constructor}}
// expected-error@#cwg1658-F5-copy-ctor {{defaulting this copy constructor would delete it after its first declaration}}
// expected-note@#cwg1658-F5 {{copy constructor of 'F' is implicitly deleted because base class 'A' has an inaccessible copy constructor}}
F::F(F&&) = default; // #cwg1658-F5-move-ctor
// cxx98-error@-1 {{rvalue references are a C++11 extension}}
// cxx98-error@-2 {{defaulted function definitions are a C++11 extension}}
// cxx98-error@-3 {{inherited virtual base class 'A' has private move constructor}}
// cxx98-note@-4 {{in defaulted move constructor for 'cwg1658::CopyCtor::F' first required here}}
// cxx98-note@#cwg1658-A5 {{implicitly declared private here}}
// since-cxx11-error@#cwg1658-F5-move-ctor {{defaulting this move constructor would delete it after its first declaration}}
// since-cxx11-note@#cwg1658-F5 {{move constructor of 'F' is implicitly deleted because base class 'A' has an inaccessible move constructor}}
// expected-error@#cwg1658-F5-move-ctor {{defaulting this move constructor would delete it after its first declaration}}
// expected-note@#cwg1658-F5 {{move constructor of 'F' is implicitly deleted because base class 'A' has an inaccessible move constructor}}
}

// assignment case is superseded by cwg2180
Expand Down
14 changes: 4 additions & 10 deletions clang/test/CXX/drs/dr21xx.cpp
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Expand Up @@ -246,19 +246,13 @@ namespace cwg2180 { // cwg2180: yes
};
B &B::operator=(const B&) = default; // #cwg2180-B-copy
// cxx98-error@-1 {{defaulted function definitions are a C++11 extension}}
// cxx98-error@-2 {{'operator=' is a private member of 'cwg2180::A'}}
// cxx98-note@-3 {{in defaulted copy assignment operator for 'cwg2180::B' first required here}}
// cxx98-note@#cwg2180-A-copy {{implicitly declared private here}}
// since-cxx11-error@#cwg2180-B-copy {{defaulting this copy assignment operator would delete it after its first declaration}}
// since-cxx11-note@#cwg2180-B {{copy assignment operator of 'B' is implicitly deleted because base class 'A' has an inaccessible copy assignment operator}}
// expected-error@#cwg2180-B-copy {{defaulting this copy assignment operator would delete it after its first declaration}}
// expected-note@#cwg2180-B {{copy assignment operator of 'B' is implicitly deleted because base class 'A' has an inaccessible copy assignment operator}}
B &B::operator=(B&&) = default; // #cwg2180-B-move
// cxx98-error@-1 {{rvalue references are a C++11 extension}}
// cxx98-error@-2 {{defaulted function definitions are a C++11 extension}}
// cxx98-error@-3 {{'operator=' is a private member of 'cwg2180::A'}}
// cxx98-note@-4 {{in defaulted move assignment operator for 'cwg2180::B' first required here}}
// cxx98-note@#cwg2180-A-move {{implicitly declared private here}}
// since-cxx11-error@#cwg2180-B-move {{defaulting this move assignment operator would delete it after its first declaration}}
// since-cxx11-note@#cwg2180-B {{move assignment operator of 'B' is implicitly deleted because base class 'A' has an inaccessible move assignment operator}}
// expected-error@#cwg2180-B-move {{defaulting this move assignment operator would delete it after its first declaration}}
// expected-note@#cwg2180-B {{move assignment operator of 'B' is implicitly deleted because base class 'A' has an inaccessible move assignment operator}}
}

namespace cwg2199 { // cwg2199: 3.8
Expand Down
34 changes: 31 additions & 3 deletions clang/test/SemaCXX/cxx0x-cursory-default-delete.cpp
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@@ -1,4 +1,11 @@
// RUN: %clang_cc1 -std=c++11 -fsyntax-only -verify %s
// RUN: %clang_cc1 -std=c++03 -Wno-c++11-extensions -fsyntax-only -verify %s

#if __cplusplus < 201103L
#define static_assert __extension__ _Static_assert
#define nullptr 0
#define noexcept throw()
#endif

struct non_copiable {
non_copiable(const non_copiable&) = delete; // expected-note {{marked deleted here}}
Expand All @@ -25,10 +32,12 @@ void fn1 () {
non_const_copy ncc;
non_const_copy ncc2 = ncc;
ncc = ncc2;
#if __cplusplus >= 201103L
const non_const_copy cncc{};
#endif
const non_const_copy cncc1; // expected-error {{default initialization of an object of const type 'const non_const_copy' without a user-provided default constructor}}
non_const_copy ncc3 = cncc; // expected-error {{no matching}}
ncc = cncc; // expected-error {{no viable overloaded}}
non_const_copy ncc3 = cncc1; // expected-error {{no matching}}
ncc = cncc1; // expected-error {{no viable overloaded}}
};

struct no_fields { };
Expand Down Expand Up @@ -196,7 +205,7 @@ struct except_spec_d_match : except_spec_a, except_spec_b {
struct S { S(); };
S::S() __attribute((noreturn)) = default;

using size_t = decltype(sizeof(0));
using size_t = __SIZE_TYPE__;
void *operator new(size_t) = delete; // expected-error {{deleted definition must be first declaration}} expected-note {{implicit}}
void operator delete(void *) noexcept = delete; // expected-error {{deleted definition must be first declaration}} expected-note {{implicit}}

Expand All @@ -217,3 +226,22 @@ namespace deleted_overrides_deleted {
template<typename T> struct B : A { virtual void f() = delete; };
template struct B<int>;
}

namespace GH90605 {
struct Element {
Element& operator=(const Element&) = delete; // #GH90605-Element-assign
};

struct S {
Element i; // #GH90605-i

S& operator=(const S&) = default;
// expected-warning@-1 {{explicitly defaulted copy assignment operator is implicitly deleted}}
// expected-note@#GH90605-i {{copy assignment operator of 'S' is implicitly deleted because field 'i' has a deleted copy assignment operator}}
// expected-note@#GH90605-Element-assign {{'operator=' has been explicitly marked deleted here}}
// expected-note@-4 {{replace 'default' with 'delete'}}
};

static_assert(!__is_trivially_assignable(S&, const S&), "");
static_assert(!__is_assignable(S&, const S&), "");
}
13 changes: 13 additions & 0 deletions clang/test/SemaCXX/cxx0x-defaulted-functions.cpp
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@@ -1,4 +1,9 @@
// RUN: %clang_cc1 -std=c++11 -fsyntax-only -verify -fcxx-exceptions -Wno-deprecated-builtins %s
// RUN: %clang_cc1 -std=c++03 -Wno-c++11-extensions -fsyntax-only -verify -fcxx-exceptions -Wno-deprecated-builtins %s

#if __cplusplus < 201103L
#define static_assert _Static_assert
#endif

void fn() = default; // expected-error {{only special member}}
struct foo {
Expand Down Expand Up @@ -43,6 +48,7 @@ void tester() {
b = c;
}

#if __cplusplus >= 201103L
template<typename T> struct S : T {
constexpr S() = default; // expected-note {{previous declaration is here}}
constexpr S(const S&) = default; // expected-note {{previous declaration is here}}
Expand Down Expand Up @@ -118,6 +124,7 @@ namespace DefaultedFnExceptionSpec {
*p = *p; // expected-note {{instantiation of}}
}
}
#endif

namespace PR13527 {
struct X {
Expand All @@ -135,6 +142,7 @@ namespace PR13527 {
X &X::operator=(X&&) = default; // expected-error {{redefinition}}
X::~X() = default; // expected-error {{redefinition}}

#if __cplusplus >= 201103L
struct Y {
Y() = default;
Y(const Y&) = default;
Expand All @@ -149,6 +157,7 @@ namespace PR13527 {
Y &Y::operator=(const Y&) noexcept = default; // expected-error {{definition of explicitly defaulted}}
Y &Y::operator=(Y&&) noexcept = default; // expected-error {{definition of explicitly defaulted}}
Y::~Y() = default; // expected-error {{definition of explicitly defaulted}}
#endif
}

namespace PR27699 {
Expand Down Expand Up @@ -185,6 +194,7 @@ extern "C" { // expected-note {{extern "C" language linkage specification begins
void PR13573(const _Tp&) = delete;
}

#if __cplusplus >= 201103L
namespace PR15597 {
template<typename T> struct A {
A() noexcept(true) = default;
Expand All @@ -197,6 +207,7 @@ namespace PR15597 {
A<int> a;
B<int> b;
}
#endif

namespace PR27941 {
struct ExplicitBool {
Expand Down Expand Up @@ -245,6 +256,7 @@ E<Type>::E(const int&) {} // expected-error {{definition of explicitly defaulte

}

#if __cplusplus >= 201103L
namespace P1286R2 {
struct X {
X();
Expand Down Expand Up @@ -286,3 +298,4 @@ struct B {
auto operator = (RM<B>) -> RV<B> = delete;
};
}
#endif
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