https://github.com/cor3ntin created https://github.com/llvm/llvm-project/pull/161163
We failed to check that the trivial constructor where eligible (this implies non deleted).
Fixes #160610
>From 8a5da1fe903d6b42b11fd118888eb51078526beb Mon Sep 17 00:00:00 2001
From: Corentin Jabot <corentinjabot at gmail.com>
Date: Mon, 29 Sep 2025 11:35:07 +0200
Subject: [PATCH] [Clang] Fixes __builtin_is_implicit_lifetime for types with a
user-provided Ctr
We failed to check that the trivial constructor where eligible
(this implies non deleted).
Fixes #160610
---
clang/docs/ReleaseNotes.rst | 1 +
clang/lib/Sema/SemaTypeTraits.cpp | 17 +++++++------
clang/test/SemaCXX/type-traits.cpp | 40 ++++++++++++++++++++++++++++++
3 files changed, 51 insertions(+), 7 deletions(-)
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 270b5d336eba7..e8deae50e4cb0 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -432,6 +432,7 @@ Bug Fixes to C++ Support
- Fix an assertion failure when taking the address on a non-type template parameter argument of
object type. (#GH151531)
- Suppress ``-Wdouble-promotion`` when explicitly asked for with C++ list initialization (#GH33409).
+- Fix the result of `__builtin_is_implicit_lifetime` for types with a user-provided constructor. (#GH160610)
Bug Fixes to AST Handling
^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/clang/lib/Sema/SemaTypeTraits.cpp b/clang/lib/Sema/SemaTypeTraits.cpp
index c2427dcf52538..6c798d6acb0a0 100644
--- a/clang/lib/Sema/SemaTypeTraits.cpp
+++ b/clang/lib/Sema/SemaTypeTraits.cpp
@@ -1163,13 +1163,16 @@ static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
// - it has at least one trivial eligible constructor and a trivial,
// non-deleted destructor.
const CXXDestructorDecl *Dtor = RD->getDestructor();
- if (UnqualT->isAggregateType())
- if (Dtor && !Dtor->isUserProvided())
- return true;
- if (RD->hasTrivialDestructor() && (!Dtor || !Dtor->isDeleted()))
- if (RD->hasTrivialDefaultConstructor() ||
- RD->hasTrivialCopyConstructor() || RD->hasTrivialMoveConstructor())
- return true;
+ if (UnqualT->isAggregateType() && (!Dtor || !Dtor->isUserProvided()))
+ return true;
+ if (RD->hasTrivialDestructor() && (!Dtor || !Dtor->isDeleted())) {
+ for (CXXConstructorDecl *Ctr : RD->ctors()) {
+ if (Ctr->isIneligibleOrNotSelected() || Ctr->isDeleted())
+ continue;
+ if (Ctr->isTrivial())
+ return true;
+ }
+ }
return false;
}
case UTT_IsIntangibleType:
diff --git a/clang/test/SemaCXX/type-traits.cpp b/clang/test/SemaCXX/type-traits.cpp
index 3f0124755c674..f8a88b1d0c0ad 100644
--- a/clang/test/SemaCXX/type-traits.cpp
+++ b/clang/test/SemaCXX/type-traits.cpp
@@ -2038,6 +2038,46 @@ void is_implicit_lifetime(int n) {
static_assert(__builtin_is_implicit_lifetime(int * __restrict));
}
+namespace GH160610 {
+class NonAggregate {
+public:
+ NonAggregate() = default;
+
+ NonAggregate(const NonAggregate&) = delete;
+ NonAggregate& operator=(const NonAggregate&) = delete;
+private:
+ int num;
+};
+
+class DataMemberInitializer {
+public:
+ DataMemberInitializer() = default;
+
+ DataMemberInitializer(const DataMemberInitializer&) = delete;
+ DataMemberInitializer& operator=(const DataMemberInitializer&) = delete;
+private:
+ int num = 0;
+};
+
+class UserProvidedConstructor {
+public:
+ UserProvidedConstructor() {}
+
+ UserProvidedConstructor(const UserProvidedConstructor&) = delete;
+ UserProvidedConstructor& operator=(const UserProvidedConstructor&) = delete;
+};
+
+template <typename T>
+class Tpl {
+ Tpl() requires false = default ;
+};
+
+static_assert(__builtin_is_implicit_lifetime(NonAggregate));
+static_assert(!__builtin_is_implicit_lifetime(DataMemberInitializer));
+static_assert(!__builtin_is_implicit_lifetime(UserProvidedConstructor));
+static_assert(!__builtin_is_implicit_lifetime(Tpl<int>));
+}
+
void is_signed()
{
//static_assert(__is_signed(char));