PR for llvm/llvm-project#79762 #79763
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… of the same type) (llvm#77768)" This reverts commit 9247013. Causes compilation errors on valid code, see llvm#77768 (comment). (cherry picked from commit 6e4930c)
llvmbot
added
clang
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@llvm/pr-subscribers-clang @llvm/pr-subscribers-libcxx Author: None (llvmbot) Changesresolves llvm/llvm-project#79762 Full diff: https://github.com/llvm/llvm-project/pull/79763.diff 7 Files Affected:
diff --git a/clang/lib/Sema/SemaInit.cpp b/clang/lib/Sema/SemaInit.cpp
index 91e4cb7b68a24a9..457fa377355a97c 100644
--- a/clang/lib/Sema/SemaInit.cpp
+++ b/clang/lib/Sema/SemaInit.cpp
@@ -4200,7 +4200,7 @@ static OverloadingResult ResolveConstructorOverload(
/// \param IsListInit Is this list-initialization?
/// \param IsInitListCopy Is this non-list-initialization resulting from a
/// list-initialization from {x} where x is the same
-/// aggregate type as the entity?
+/// type as the entity?
static void TryConstructorInitialization(Sema &S,
const InitializedEntity &Entity,
const InitializationKind &Kind,
@@ -4230,14 +4230,6 @@ static void TryConstructorInitialization(Sema &S,
Entity.getKind() !=
InitializedEntity::EK_LambdaToBlockConversionBlockElement);
- bool CopyElisionPossible = false;
- auto ElideConstructor = [&] {
- // Convert qualifications if necessary.
- Sequence.AddQualificationConversionStep(DestType, VK_PRValue);
- if (ILE)
- Sequence.RewrapReferenceInitList(DestType, ILE);
- };
-
// C++17 [dcl.init]p17:
// - If the initializer expression is a prvalue and the cv-unqualified
// version of the source type is the same class as the class of the
@@ -4250,17 +4242,11 @@ static void TryConstructorInitialization(Sema &S,
if (S.getLangOpts().CPlusPlus17 && !RequireActualConstructor &&
UnwrappedArgs.size() == 1 && UnwrappedArgs[0]->isPRValue() &&
S.Context.hasSameUnqualifiedType(UnwrappedArgs[0]->getType(), DestType)) {
- if (ILE && !DestType->isAggregateType()) {
- // CWG2311: T{ prvalue_of_type_T } is not eligible for copy elision
- // Make this an elision if this won't call an initializer-list
- // constructor. (Always on an aggregate type or check constructors first.)
- assert(!IsInitListCopy &&
- "IsInitListCopy only possible with aggregate types");
- CopyElisionPossible = true;
- } else {
- ElideConstructor();
- return;
- }
+ // Convert qualifications if necessary.
+ Sequence.AddQualificationConversionStep(DestType, VK_PRValue);
+ if (ILE)
+ Sequence.RewrapReferenceInitList(DestType, ILE);
+ return;
}
const RecordType *DestRecordType = DestType->getAs<RecordType>();
@@ -4305,12 +4291,6 @@ static void TryConstructorInitialization(Sema &S,
S, Kind.getLocation(), Args, CandidateSet, DestType, Ctors, Best,
CopyInitialization, AllowExplicit,
/*OnlyListConstructors=*/true, IsListInit, RequireActualConstructor);
-
- if (CopyElisionPossible && Result == OR_No_Viable_Function) {
- // No initializer list candidate
- ElideConstructor();
- return;
- }
}
// C++11 [over.match.list]p1:
@@ -4592,9 +4572,9 @@ static void TryListInitialization(Sema &S,
return;
}
- // C++11 [dcl.init.list]p3, per DR1467 and DR2137:
- // - If T is an aggregate class and the initializer list has a single element
- // of type cv U, where U is T or a class derived from T, the object is
+ // C++11 [dcl.init.list]p3, per DR1467:
+ // - If T is a class type and the initializer list has a single element of
+ // type cv U, where U is T or a class derived from T, the object is
// initialized from that element (by copy-initialization for
// copy-list-initialization, or by direct-initialization for
// direct-list-initialization).
@@ -4605,7 +4585,7 @@ static void TryListInitialization(Sema &S,
// - Otherwise, if T is an aggregate, [...] (continue below).
if (S.getLangOpts().CPlusPlus11 && InitList->getNumInits() == 1 &&
!IsDesignatedInit) {
- if (DestType->isRecordType() && DestType->isAggregateType()) {
+ if (DestType->isRecordType()) {
QualType InitType = InitList->getInit(0)->getType();
if (S.Context.hasSameUnqualifiedType(InitType, DestType) ||
S.IsDerivedFrom(InitList->getBeginLoc(), InitType, DestType)) {
diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index 030878899b81223..c9eb67898356334 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -1568,37 +1568,19 @@ TryUserDefinedConversion(Sema &S, Expr *From, QualType ToType,
// called for those cases.
if (CXXConstructorDecl *Constructor
= dyn_cast<CXXConstructorDecl>(ICS.UserDefined.ConversionFunction)) {
- QualType FromType;
- SourceLocation FromLoc;
- // C++11 [over.ics.list]p6, per DR2137:
- // C++17 [over.ics.list]p6:
- // If C is not an initializer-list constructor and the initializer list
- // has a single element of type cv U, where U is X or a class derived
- // from X, the implicit conversion sequence has Exact Match rank if U is
- // X, or Conversion rank if U is derived from X.
- if (const auto *InitList = dyn_cast<InitListExpr>(From);
- InitList && InitList->getNumInits() == 1 &&
- !S.isInitListConstructor(Constructor)) {
- const Expr *SingleInit = InitList->getInit(0);
- FromType = SingleInit->getType();
- FromLoc = SingleInit->getBeginLoc();
- } else {
- FromType = From->getType();
- FromLoc = From->getBeginLoc();
- }
- QualType FromCanon =
- S.Context.getCanonicalType(FromType.getUnqualifiedType());
+ QualType FromCanon
+ = S.Context.getCanonicalType(From->getType().getUnqualifiedType());
QualType ToCanon
= S.Context.getCanonicalType(ToType).getUnqualifiedType();
if (Constructor->isCopyConstructor() &&
(FromCanon == ToCanon ||
- S.IsDerivedFrom(FromLoc, FromCanon, ToCanon))) {
+ S.IsDerivedFrom(From->getBeginLoc(), FromCanon, ToCanon))) {
// Turn this into a "standard" conversion sequence, so that it
// gets ranked with standard conversion sequences.
DeclAccessPair Found = ICS.UserDefined.FoundConversionFunction;
ICS.setStandard();
ICS.Standard.setAsIdentityConversion();
- ICS.Standard.setFromType(FromType);
+ ICS.Standard.setFromType(From->getType());
ICS.Standard.setAllToTypes(ToType);
ICS.Standard.CopyConstructor = Constructor;
ICS.Standard.FoundCopyConstructor = Found;
@@ -5324,18 +5306,18 @@ TryListConversion(Sema &S, InitListExpr *From, QualType ToType,
IsDesignatedInit)
return Result;
- // Per DR1467 and DR2137:
- // If the parameter type is an aggregate class X and the initializer list
- // has a single element of type cv U, where U is X or a class derived from
- // X, the implicit conversion sequence is the one required to convert the
- // element to the parameter type.
+ // Per DR1467:
+ // If the parameter type is a class X and the initializer list has a single
+ // element of type cv U, where U is X or a class derived from X, the
+ // implicit conversion sequence is the one required to convert the element
+ // to the parameter type.
//
// Otherwise, if the parameter type is a character array [... ]
// and the initializer list has a single element that is an
// appropriately-typed string literal (8.5.2 [dcl.init.string]), the
// implicit conversion sequence is the identity conversion.
if (From->getNumInits() == 1 && !IsDesignatedInit) {
- if (ToType->isRecordType() && ToType->isAggregateType()) {
+ if (ToType->isRecordType()) {
QualType InitType = From->getInit(0)->getType();
if (S.Context.hasSameUnqualifiedType(InitType, ToType) ||
S.IsDerivedFrom(From->getBeginLoc(), InitType, ToType))
diff --git a/clang/test/CXX/drs/dr14xx.cpp b/clang/test/CXX/drs/dr14xx.cpp
index 4c29d03a6e117a3..d262f6f9dcab796 100644
--- a/clang/test/CXX/drs/dr14xx.cpp
+++ b/clang/test/CXX/drs/dr14xx.cpp
@@ -488,6 +488,16 @@ namespace dr1467 { // dr1467: 3.7 c++11
}
} // nonaggregate
+ namespace SelfInitIsNotListInit {
+ struct S {
+ S();
+ explicit S(S &);
+ S(const S &);
+ };
+ S s1;
+ S s2 = {s1}; // ok, not list-initialization so we pick the non-explicit constructor
+ }
+
struct NestedInit { int a, b, c; };
NestedInit ni[1] = {{NestedInit{1, 2, 3}}};
diff --git a/clang/test/CXX/drs/dr21xx.cpp b/clang/test/CXX/drs/dr21xx.cpp
index 87040246aa5cd40..a7e50df3f374be9 100644
--- a/clang/test/CXX/drs/dr21xx.cpp
+++ b/clang/test/CXX/drs/dr21xx.cpp
@@ -11,16 +11,6 @@
// cxx98-error@-1 {{variadic macros are a C99 feature}}
#endif
-namespace std {
- __extension__ typedef __SIZE_TYPE__ size_t;
-
- template<typename E> struct initializer_list {
- const E *p; size_t n;
- initializer_list(const E *p, size_t n);
- initializer_list();
- };
-}
-
namespace dr2100 { // dr2100: 12
template<const int *P, bool = true> struct X {};
template<typename T> struct A {
@@ -142,41 +132,6 @@ namespace dr2126 { // dr2126: 12
#endif
}
-namespace dr2137 { // dr2137: 18
-#if __cplusplus >= 201103L
- struct Q {
- Q();
- Q(Q&&);
- Q(std::initializer_list<Q>) = delete; // #dr2137-Qcons
- };
-
- Q x = Q { Q() };
- // since-cxx11-error@-1 {{call to deleted constructor of 'Q'}}
- // since-cxx11-note@#dr2137-Qcons {{'Q' has been explicitly marked deleted here}}
-
- int f(Q); // #dr2137-f
- int y = f({ Q() });
- // since-cxx11-error@-1 {{call to deleted constructor of 'Q'}}
- // since-cxx11-note@#dr2137-Qcons {{'Q' has been explicitly marked deleted here}}
- // since-cxx11-note@#dr2137-f {{passing argument to parameter here}}
-
- struct U {
- U();
- U(const U&);
- };
-
- struct Derived : U {
- Derived();
- Derived(const Derived&);
- } d;
-
- int g(Derived);
- int g(U(&&)[1]) = delete;
-
- int z = g({ d });
-#endif
-}
-
namespace dr2140 { // dr2140: 9
#if __cplusplus >= 201103L
union U { int a; decltype(nullptr) b; };
diff --git a/clang/test/CXX/drs/dr23xx.cpp b/clang/test/CXX/drs/dr23xx.cpp
index d8556998315c777..03077ae9239a458 100644
--- a/clang/test/CXX/drs/dr23xx.cpp
+++ b/clang/test/CXX/drs/dr23xx.cpp
@@ -6,16 +6,6 @@
// RUN: %clang_cc1 -std=c++23 %s -verify=expected,since-cxx11,since-cxx14,since-cxx17,since-cxx20 -fexceptions -fcxx-exceptions -pedantic-errors 2>&1 | FileCheck %s
// RUN: %clang_cc1 -std=c++2c %s -verify=expected,since-cxx11,since-cxx14,since-cxx17,since-cxx20 -fexceptions -fcxx-exceptions -pedantic-errors 2>&1 | FileCheck %s
-namespace std {
- __extension__ typedef __SIZE_TYPE__ size_t;
-
- template<typename E> struct initializer_list {
- const E *p; size_t n;
- initializer_list(const E *p, size_t n);
- initializer_list();
- };
-}
-
#if __cplusplus >= 201103L
namespace dr2303 { // dr2303: 12
template <typename... T>
@@ -57,81 +47,6 @@ void g() {
} //namespace dr2303
#endif
-namespace dr2311 { // dr2311: 18 open
-#if __cplusplus >= 201707L
-template<typename T>
-void test() {
- // Ensure none of these try to call a move constructor.
- T a = T{T(0)};
- T b{T(0)};
- auto c{T(0)};
- T d = {T(0)};
- auto e = {T(0)};
-#if __cplusplus >= 202302L
- auto f = auto{T(0)};
-#endif
- void(*fn)(T);
- fn({T(0)});
-}
-
-struct NonMovable {
- NonMovable(int);
- NonMovable(NonMovable&&) = delete;
-};
-struct NonMovableNonApplicableIList {
- NonMovableNonApplicableIList(int);
- NonMovableNonApplicableIList(NonMovableNonApplicableIList&&) = delete;
- NonMovableNonApplicableIList(std::initializer_list<int>);
-};
-struct ExplicitMovable {
- ExplicitMovable(int);
- explicit ExplicitMovable(ExplicitMovable&&);
-};
-struct ExplicitNonMovable {
- ExplicitNonMovable(int);
- explicit ExplicitNonMovable(ExplicitNonMovable&&) = delete;
-};
-struct ExplicitNonMovableNonApplicableIList {
- ExplicitNonMovableNonApplicableIList(int);
- explicit ExplicitNonMovableNonApplicableIList(ExplicitNonMovableNonApplicableIList&&) = delete;
- ExplicitNonMovableNonApplicableIList(std::initializer_list<int>);
-};
-struct CopyOnly {
- CopyOnly(int);
- CopyOnly(const CopyOnly&);
- CopyOnly(CopyOnly&&) = delete;
-};
-struct ExplicitCopyOnly {
- ExplicitCopyOnly(int);
- explicit ExplicitCopyOnly(const ExplicitCopyOnly&);
- explicit ExplicitCopyOnly(ExplicitCopyOnly&&) = delete;
-};
-
-template void test<NonMovable>();
-template void test<NonMovableNonApplicableIList>();
-template void test<ExplicitMovable>();
-template void test<ExplicitNonMovable>();
-template void test<ExplicitNonMovableNonApplicableIList>();
-template void test<CopyOnly>();
-template void test<ExplicitCopyOnly>();
-
-struct any {
- template<typename T>
- any(T&&);
-};
-
-template<typename T>
-struct X {
- X();
- X(T) = delete; // #dr2311-X
-};
-
-X<std::initializer_list<any>> x{ X<std::initializer_list<any>>() };
-// since-cxx17-error@-1 {{call to deleted constructor of 'X<std::initializer_list<any>>'}}
-// since-cxx17-note@#dr2311-X {{'X' has been explicitly marked deleted here}}
-#endif
-}
-
// dr2331: na
// dr2335 is in dr2335.cxx
diff --git a/clang/www/cxx_dr_status.html b/clang/www/cxx_dr_status.html
index f0d835fc091ceae..c9d21f096a34c6f 100755
--- a/clang/www/cxx_dr_status.html
+++ b/clang/www/cxx_dr_status.html
@@ -12630,7 +12630,7 @@ <h2 id="cxxdr">C++ defect report implementation status</h2>
<td><a href="https://cplusplus.github.io/CWG/issues/2137.html">2137</a></td>
<td>CD4</td>
<td>List-initialization from object of same type</td>
- <td class="unreleased" align="center">Clang 18</td>
+ <td class="unknown" align="center">Unknown</td>
</tr>
<tr id="2138">
<td><a href="https://cplusplus.github.io/CWG/issues/2138.html">2138</a></td>
@@ -13674,7 +13674,7 @@ <h2 id="cxxdr">C++ defect report implementation status</h2>
<td><a href="https://cplusplus.github.io/CWG/issues/2311.html">2311</a></td>
<td>open</td>
<td>Missed case for guaranteed copy elision</td>
- <td class="unreleased" align="center">Clang 18</td>
+ <td align="center">Not resolved</td>
</tr>
<tr id="2312">
<td><a href="https://cplusplus.github.io/CWG/issues/2312.html">2312</a></td>
diff --git a/libcxx/test/std/utilities/utility/pairs/pairs.pair/ctor.pair_U_V_move.pass.cpp b/libcxx/test/std/utilities/utility/pairs/pairs.pair/ctor.pair_U_V_move.pass.cpp
index 30fdb19fd3aebeb..3b2d093eb34d490 100644
--- a/libcxx/test/std/utilities/utility/pairs/pairs.pair/ctor.pair_U_V_move.pass.cpp
+++ b/libcxx/test/std/utilities/utility/pairs/pairs.pair/ctor.pair_U_V_move.pass.cpp
@@ -121,26 +121,7 @@ int main(int, char**)
test_pair_rv<CopyOnly, CopyOnly&>();
test_pair_rv<CopyOnly, CopyOnly&&>();
- /* For ExplicitTypes::CopyOnly, two of the viable candidates for initializing from a non-const xvalue are:
- * pair(const pair&); // (defaulted copy constructor)
- * template<class U1, class U2> explicit pair(const pair<U1, U2>&&); [U1 = ExplicitTypes::CopyOnly, U2 = int]
- * This results in diverging behavior for test_convertible which uses copy-list-initialization
- * Prior to CWG2137, this would have selected the first (non-explicit) ctor as explicit ctors would not be considered
- * Afterwards, it should select the second since it is a better match, and then failed because it is explicit
- *
- * This may change with future defect reports, and some compilers only have partial support for CWG2137,
- * so use std::is_convertible directly to avoid a copy-list-initialization
- */
- {
- using P1 = std::pair<ExplicitTypes::CopyOnly, int>;
- using P2 = std::pair<int, ExplicitTypes::CopyOnly>;
- using UP1 = std::pair<ExplicitTypes::CopyOnly, int>&&;
- using UP2 = std::pair<int, ExplicitTypes::CopyOnly>&&;
- static_assert(std::is_constructible<P1, UP1>::value, "");
- static_assert(std::is_convertible<P1, UP1>::value, "");
- static_assert(std::is_constructible<P2, UP2>::value, "");
- static_assert(std::is_convertible<P2, UP2>::value, "");
- }
+ test_pair_rv<ExplicitTypes::CopyOnly, ExplicitTypes::CopyOnly>();
test_pair_rv<ExplicitTypes::CopyOnly, ExplicitTypes::CopyOnly&, true, false>();
test_pair_rv<ExplicitTypes::CopyOnly, ExplicitTypes::CopyOnly&&, true, false>();
|
You can test this locally with the following command:git-clang-format --diff 27654471cc7acfca733c104e2ec24f882cfc6132 a9c2fe6d85b9136199acfcdacf01a2db0bdfc52a -- clang/lib/Sema/SemaInit.cpp clang/lib/Sema/SemaOverload.cpp clang/test/CXX/drs/dr14xx.cpp clang/test/CXX/drs/dr21xx.cpp clang/test/CXX/drs/dr23xx.cpp libcxx/test/std/utilities/utility/pairs/pairs.pair/ctor.pair_U_V_move.pass.cppView the diff from clang-format here.diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index c9eb678983..018043c3b3 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -1568,8 +1568,8 @@ TryUserDefinedConversion(Sema &S, Expr *From, QualType ToType,
// called for those cases.
if (CXXConstructorDecl *Constructor
= dyn_cast<CXXConstructorDecl>(ICS.UserDefined.ConversionFunction)) {
- QualType FromCanon
- = S.Context.getCanonicalType(From->getType().getUnqualifiedType());
+ QualType FromCanon =
+ S.Context.getCanonicalType(From->getType().getUnqualifiedType());
QualType ToCanon
= S.Context.getCanonicalType(ToType).getUnqualifiedType();
if (Constructor->isCopyConstructor() &&
|
Endilll
approved these changes
Jan 28, 2024
ldionne
approved these changes
Jan 29, 2024
|
Merged: b73cd5e |
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resolves #79762