[clang] [llvm] [LifetimeSafety] Add lifetimebound inference for std::make_unique (PR #191632)
Utkarsh Saxena via cfe-commits
cfe-commits at lists.llvm.org
Wed Apr 15 10:47:58 PDT 2026
https://github.com/usx95 updated https://github.com/llvm/llvm-project/pull/191632
>From ea1e700d3c41ca48563e27c1a57fd7a86be50d8d Mon Sep 17 00:00:00 2001
From: Utkarsh Saxena <usx at google.com>
Date: Sat, 11 Apr 2026 13:11:00 +0000
Subject: [PATCH 1/9] Make Unique inference
---
a.o | Bin 0 -> 3448 bytes
.../LifetimeSafety/FactsGenerator.cpp | 3 +-
clang/lib/Analysis/LifetimeSafety/Origins.cpp | 1 +
clang/lib/Sema/SemaAttr.cpp | 55 ++++++++++++++
.../lib/Sema/SemaTemplateInstantiateDecl.cpp | 2 +
clang/test/Sema/Inputs/lifetime-analysis.h | 3 +
.../Sema/warn-lifetime-analysis-nocfg.cpp | 11 +++
clang/test/Sema/warn-lifetime-safety.cpp | 70 +++++++++++++++++-
8 files changed, 141 insertions(+), 4 deletions(-)
create mode 100644 a.o
diff --git a/a.o b/a.o
new file mode 100644
index 0000000000000000000000000000000000000000..62582c83f3bfdb00d8640bee02912561d1d29b77
GIT binary patch
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diff --git a/clang/lib/Analysis/LifetimeSafety/FactsGenerator.cpp b/clang/lib/Analysis/LifetimeSafety/FactsGenerator.cpp
index 2a2ef88987286..be9dd03dfe3da 100644
--- a/clang/lib/Analysis/LifetimeSafety/FactsGenerator.cpp
+++ b/clang/lib/Analysis/LifetimeSafety/FactsGenerator.cpp
@@ -489,7 +489,8 @@ void FactsGenerator::VisitCXXOperatorCallExpr(const CXXOperatorCallExpr *OCE) {
hasOrigins(OCE->getArg(0)->getType())) {
// Pointer-like types: assignment inherently propagates origins.
QualType LHSTy = OCE->getArg(0)->getType();
- if (LHSTy->isPointerOrReferenceType() || isGslPointerType(LHSTy)) {
+ if (LHSTy->isPointerOrReferenceType() || isGslPointerType(LHSTy) ||
+ isGslOwnerType(LHSTy)) {
handleAssignment(OCE->getArg(0), OCE->getArg(1));
return;
}
diff --git a/clang/lib/Analysis/LifetimeSafety/Origins.cpp b/clang/lib/Analysis/LifetimeSafety/Origins.cpp
index fdd2671dee2e0..72c61042afb3a 100644
--- a/clang/lib/Analysis/LifetimeSafety/Origins.cpp
+++ b/clang/lib/Analysis/LifetimeSafety/Origins.cpp
@@ -68,6 +68,7 @@ class LifetimeAnnotatedOriginTypeCollector
}
bool shouldVisitLambdaBody() const { return false; }
+ bool shouldVisitTemplateInstantiations() const { return true; }
const llvm::SmallVector<QualType> &getCollectedTypes() const {
return CollectedTypes;
diff --git a/clang/lib/Sema/SemaAttr.cpp b/clang/lib/Sema/SemaAttr.cpp
index 7c79f954e6743..d173b1ba58d8e 100644
--- a/clang/lib/Sema/SemaAttr.cpp
+++ b/clang/lib/Sema/SemaAttr.cpp
@@ -250,6 +250,61 @@ void Sema::inferLifetimeBoundAttribute(FunctionDecl *FD) {
}
return;
}
+
+ // Handle std::make_unique to propagate lifetimebound attributes from the
+ // constructed type's constructor to make_unique's parameters.
+ if (FD->isInStdNamespace() && FD->getDeclName().isIdentifier() &&
+ FD->getName() == "make_unique") {
+ if (!FD->isFunctionTemplateSpecialization())
+ return;
+
+ const TemplateArgumentList *TAL = FD->getTemplateSpecializationArgs();
+ if (!TAL || TAL->size() < 1)
+ return;
+
+ // make_unique's first template argument is the type being constructed.
+ TemplateArgument TA = TAL->get(0);
+ if (TA.getKind() != TemplateArgument::Type)
+ return;
+
+ QualType T = TA.getAsType();
+ const auto *RD = T->getAsCXXRecordDecl();
+ if (!RD)
+ return;
+
+ // Find the constructor that matches make_unique's arguments.
+ for (const auto *Ctor : RD->ctors()) {
+ if (Ctor->getNumParams() != FD->getNumParams())
+ continue;
+
+ bool Compatible = true;
+ for (unsigned i = 0; i < Ctor->getNumParams(); ++i) {
+ QualType CtorParamType = Ctor->getParamDecl(i)->getType();
+ QualType FDParamType = FD->getParamDecl(i)->getType();
+ // Compare types ignoring references.
+ if (!Context.hasSameUnqualifiedType(
+ CtorParamType.getNonReferenceType(),
+ FDParamType.getNonReferenceType())) {
+ Compatible = false;
+ break;
+ }
+ }
+
+ if (!Compatible)
+ continue;
+ // Propagate lifetimebound attributes only if the constructor parameter is
+ // a reference. This avoids incorrect loan tracking when a by-value view
+ // (like string_view) is passed by reference to make_unique.
+ for (unsigned i = 0; i < Ctor->getNumParams(); ++i)
+ if (Ctor->getParamDecl(i)->hasAttr<LifetimeBoundAttr>() &&
+ Ctor->getParamDecl(i)->getType()->isReferenceType())
+ FD->getParamDecl(i)->addAttr(
+ LifetimeBoundAttr::CreateImplicit(Context, FD->getLocation()));
+ break; // Found matching constructor, done.
+ }
+ return;
+ }
+
if (auto *CMD = dyn_cast<CXXMethodDecl>(FD)) {
const auto *CRD = CMD->getParent();
if (!CRD->isInStdNamespace() || !CRD->getIdentifier())
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 09c2482168ab7..954160d4112a5 100644
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -5473,6 +5473,8 @@ TemplateDeclInstantiator::InitFunctionInstantiation(FunctionDecl *New,
SemaRef.InstantiateAttrs(TemplateArgs, Definition, New,
LateAttrs, StartingScope);
+ SemaRef.inferLifetimeBoundAttribute(New);
+
return false;
}
diff --git a/clang/test/Sema/Inputs/lifetime-analysis.h b/clang/test/Sema/Inputs/lifetime-analysis.h
index d1e847d20cc50..67e6c0f18de5c 100644
--- a/clang/test/Sema/Inputs/lifetime-analysis.h
+++ b/clang/test/Sema/Inputs/lifetime-analysis.h
@@ -205,6 +205,9 @@ struct unique_ptr {
T *get() const;
};
+template<typename T, typename... Args>
+unique_ptr<T> make_unique(Args&&... args);
+
template<typename T>
struct optional {
optional();
diff --git a/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp b/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp
index 2b6c2d3d8bdb6..e07c90f248764 100644
--- a/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp
+++ b/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp
@@ -174,6 +174,17 @@ void initLocalGslPtrWithTempOwner() {
use(global2, p2); // cfg-note 2 {{later used here}}
}
+struct LifetimeBoundCtor {
+ LifetimeBoundCtor(const MyIntOwner& obj1 [[clang::lifetimebound]]);
+ LifetimeBoundCtor(std::string_view sv [[clang::lifetimebound]]);
+};
+
+auto lifetimebound_make_unique_single_param() {
+ return std::make_unique<LifetimeBoundCtor>(MyIntOwner{}); // expected-warning {{returning address of local temporary object}} \
+ // cfg-warning {{address of stack memory is returned later}} cfg-note {{returned here}}
+}
+
+
struct Unannotated {
typedef std::vector<int>::iterator iterator;
diff --git a/clang/test/Sema/warn-lifetime-safety.cpp b/clang/test/Sema/warn-lifetime-safety.cpp
index 2aca44daeb0aa..29f4880993b42 100644
--- a/clang/test/Sema/warn-lifetime-safety.cpp
+++ b/clang/test/Sema/warn-lifetime-safety.cpp
@@ -936,6 +936,70 @@ void lifetimebound_ctor() {
(void)v; // expected-note {{later used here}}
}
+void lifetimebound_make_unique() {
+ std::unique_ptr<LifetimeBoundCtor> ptr;
+ {
+ MyObj obj;
+ ptr = std::make_unique<LifetimeBoundCtor>(obj); // expected-warning {{object whose reference is captured does not live long enough}}
+ } // expected-note {{destroyed here}}
+ (void)ptr; // expected-note {{later used here}}
+}
+
+void lifetimebound_make_unique_temp() {
+ std::unique_ptr<LifetimeBoundCtor> ptr = std::make_unique<LifetimeBoundCtor>(MyObj()); // expected-warning {{object whose reference is captured does not live long enough}} \
+ // expected-note {{destroyed here}}
+ (void)ptr; // expected-note {{later used here}}
+}
+
+struct MultiLifetimeBoundCtor {
+ MultiLifetimeBoundCtor(const MyObj& obj1 [[clang::lifetimebound]], const MyObj& obj2);
+ MultiLifetimeBoundCtor(const MyObj& obj1, const MyObj& obj2 [[clang::lifetimebound]], int);
+ MultiLifetimeBoundCtor(const MyObj& obj1 [[clang::lifetimebound]], const MyObj& obj2 [[clang::lifetimebound]], double);
+ MultiLifetimeBoundCtor(std::string_view sv [[clang::lifetimebound]]);
+};
+
+void lifetimebound_make_unique_multi_params() {
+ std::unique_ptr<MultiLifetimeBoundCtor> ptr;
+ MyObj obj_long;
+ {
+ MyObj obj_short;
+ ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_short, obj_long); // expected-warning {{object whose reference is captured does not live long enough}}
+ } // expected-note {{destroyed here}}
+ (void)ptr; // expected-note {{later used here}}
+}
+
+void lifetimebound_make_unique_multi_params2() {
+ std::unique_ptr<MultiLifetimeBoundCtor> ptr;
+ MyObj obj_long;
+ {
+ MyObj obj_short;
+ ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_long, obj_short, 1); // expected-warning {{object whose reference is captured does not live long enough}}
+ } // expected-note {{destroyed here}}
+ (void)ptr; // expected-note {{later used here}}
+}
+
+void lifetimebound_make_unique_multi_params3_1() {
+ std::unique_ptr<MultiLifetimeBoundCtor> ptr;
+ MyObj obj_long;
+ {
+ MyObj obj_short;
+ ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_short, obj_long, 1.0); // expected-warning {{object whose reference is captured does not live long enough}}
+ } // expected-note {{destroyed here}}
+ (void)ptr; // expected-note {{later used here}}
+}
+
+void lifetimebound_make_unique_multi_params3_2() {
+ std::unique_ptr<MultiLifetimeBoundCtor> ptr;
+ MyObj obj_long;
+ {
+ MyObj obj_short;
+ ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_long, obj_short, 1.0); // expected-warning {{object whose reference is captured does not live long enough}}
+ } // expected-note {{destroyed here}}
+ (void)ptr; // expected-note {{later used here}}
+}
+
+
+
View lifetimebound_return_of_local() {
MyObj stack;
return Identity(stack); // expected-warning {{address of stack memory is returned later}}
@@ -2425,9 +2489,9 @@ void owner_outlives_lifetimebound_source() {
std::unique_ptr<S> ups;
{
std::string local;
- ups = getUniqueS(local);
- }
- (void)ups; // Should warn.
+ ups = getUniqueS(local); // expected-warning {{object whose reference is captured does not live long enough}}
+ } // expected-note {{destroyed here}}
+ (void)ups; // expected-note {{later used here}}
}
} // namespace track_origins_for_lifetimebound_record_type
>From 93a273357ae251dddcdbe2f17e0c24159c922dc3 Mon Sep 17 00:00:00 2001
From: Utkarsh Saxena <usx at google.com>
Date: Sat, 11 Apr 2026 13:26:11 +0000
Subject: [PATCH 2/9] string_view and pointer parameters
---
a.o | Bin 3448 -> 2984 bytes
clang/test/Sema/warn-lifetime-safety.cpp | 24 ++++++++++++++++++++++-
2 files changed, 23 insertions(+), 1 deletion(-)
diff --git a/a.o b/a.o
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diff --git a/clang/test/Sema/warn-lifetime-safety.cpp b/clang/test/Sema/warn-lifetime-safety.cpp
index 29f4880993b42..678354341a1fb 100644
--- a/clang/test/Sema/warn-lifetime-safety.cpp
+++ b/clang/test/Sema/warn-lifetime-safety.cpp
@@ -925,6 +925,7 @@ void lifetimebound_return_reference() {
struct LifetimeBoundCtor {
LifetimeBoundCtor();
LifetimeBoundCtor(const MyObj& obj [[clang::lifetimebound]]);
+ LifetimeBoundCtor(int* p [[clang::lifetimebound]]);
};
void lifetimebound_ctor() {
@@ -951,11 +952,32 @@ void lifetimebound_make_unique_temp() {
(void)ptr; // expected-note {{later used here}}
}
+void lifetimebound_make_unique_raw_ptr() {
+ std::unique_ptr<LifetimeBoundCtor> ptr;
+ int x = 0;
+ {
+ int* p = &x;
+ // FIXME: No warning expected with current implementation
+ ptr = std::make_unique<LifetimeBoundCtor>(p);
+ }
+ (void)ptr;
+}
+
+void lifetimebound_make_unique_string_view_local() {
+ std::unique_ptr<LifetimeBoundCtor> ptr;
+ {
+ std::string s;
+ std::string_view sv(s);
+ // FIXME: No warning expected with current implementation because of reference mismatch
+ ptr = std::make_unique<LifetimeBoundCtor>(sv);
+ }
+ (void)ptr;
+}
+
struct MultiLifetimeBoundCtor {
MultiLifetimeBoundCtor(const MyObj& obj1 [[clang::lifetimebound]], const MyObj& obj2);
MultiLifetimeBoundCtor(const MyObj& obj1, const MyObj& obj2 [[clang::lifetimebound]], int);
MultiLifetimeBoundCtor(const MyObj& obj1 [[clang::lifetimebound]], const MyObj& obj2 [[clang::lifetimebound]], double);
- MultiLifetimeBoundCtor(std::string_view sv [[clang::lifetimebound]]);
};
void lifetimebound_make_unique_multi_params() {
>From 0913da75f7b756295eb3ba2ae2b9b82cc4d8518b Mon Sep 17 00:00:00 2001
From: Utkarsh Saxena <usx at google.com>
Date: Sat, 11 Apr 2026 13:27:10 +0000
Subject: [PATCH 3/9] remove a.o
---
a.o | Bin 2984 -> 0 bytes
1 file changed, 0 insertions(+), 0 deletions(-)
delete mode 100644 a.o
diff --git a/a.o b/a.o
deleted file mode 100644
index 6a53ddbada9cbc2494763f0d57e07746d0d02737..0000000000000000000000000000000000000000
GIT binary patch
literal 0
HcmV?d00001
literal 2984
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kV%y48vXuJ%6{G(Q9{Jn)kzjxAu;hlmR1RSH|K!jAACLKYRR910
>From 5606ec85aa480ae247b18bc293fd55a43ccff1fb Mon Sep 17 00:00:00 2001
From: Utkarsh Saxena <usx at google.com>
Date: Sat, 11 Apr 2026 13:36:43 +0000
Subject: [PATCH 4/9] dangling field
---
.../warn-lifetime-safety-dangling-field.cpp | 18 ++++++++++++++++++
clang/test/Sema/warn-lifetime-safety.cpp | 2 ++
2 files changed, 20 insertions(+)
diff --git a/clang/test/Sema/warn-lifetime-safety-dangling-field.cpp b/clang/test/Sema/warn-lifetime-safety-dangling-field.cpp
index 79b0183ed91ec..604adfa0c8538 100644
--- a/clang/test/Sema/warn-lifetime-safety-dangling-field.cpp
+++ b/clang/test/Sema/warn-lifetime-safety-dangling-field.cpp
@@ -185,6 +185,7 @@ struct IndirectEscape2 {
}
};
+<<<<<<< HEAD
namespace DanglingPointerFieldInBaseClass {
struct BaseWithPointer {
std::string_view view; // expected-note {{this field dangles}}
@@ -196,3 +197,20 @@ struct DerivedWithCtor : BaseWithPointer {
}
};
} // namespace DanglingPointerFieldInBaseClass
+=======
+namespace MakeUnique {
+struct MyObj {};
+
+struct LifetimeBoundCtor {
+ LifetimeBoundCtor(const MyObj& obj [[clang::lifetimebound]]);
+};
+
+struct HasUniquePtrField {
+ std::unique_ptr<LifetimeBoundCtor> field; // expected-note {{this field dangles}}
+
+ void setWithParam(MyObj obj) {
+ field = std::make_unique<LifetimeBoundCtor>(obj); // expected-warning {{address of stack memory escapes to a field}}
+ }
+};
+} // namespace MakeUnique
+>>>>>>> 6f5985bd6945 (dangling field)
diff --git a/clang/test/Sema/warn-lifetime-safety.cpp b/clang/test/Sema/warn-lifetime-safety.cpp
index 678354341a1fb..31e62cc9f72a5 100644
--- a/clang/test/Sema/warn-lifetime-safety.cpp
+++ b/clang/test/Sema/warn-lifetime-safety.cpp
@@ -974,6 +974,8 @@ void lifetimebound_make_unique_string_view_local() {
(void)ptr;
}
+
+
struct MultiLifetimeBoundCtor {
MultiLifetimeBoundCtor(const MyObj& obj1 [[clang::lifetimebound]], const MyObj& obj2);
MultiLifetimeBoundCtor(const MyObj& obj1, const MyObj& obj2 [[clang::lifetimebound]], int);
>From 0f33a12d7e2249f7b57b0d946f76c7d2611107cf Mon Sep 17 00:00:00 2001
From: Utkarsh Saxena <usx at google.com>
Date: Sat, 11 Apr 2026 13:47:55 +0000
Subject: [PATCH 5/9] lifetime suggestion
---
.../Sema/warn-lifetime-safety-suggestions.cpp | 21 +++++++++++++++++++
1 file changed, 21 insertions(+)
diff --git a/clang/test/Sema/warn-lifetime-safety-suggestions.cpp b/clang/test/Sema/warn-lifetime-safety-suggestions.cpp
index b3b13038dc344..8db96103b683d 100644
--- a/clang/test/Sema/warn-lifetime-safety-suggestions.cpp
+++ b/clang/test/Sema/warn-lifetime-safety-suggestions.cpp
@@ -67,6 +67,7 @@ struct ReturnThisPointer {
//--- test_source.cpp
#include "test_header.h"
+#include "Inputs/lifetime-analysis.h"
View definition_before_header(View a) {
return a; // expected-note {{param returned here}}
@@ -529,3 +530,23 @@ CaptureRefToBaseView test_ref_to_base_view() {
return x; // expected-note {{returned here}}
}
} // namespace capturing_constructor
+
+namespace make_unique_suggestion {
+
+struct LifetimeBoundCtor {
+ LifetimeBoundCtor(const MyObj& obj [[clang::lifetimebound]]);
+};
+
+std::unique_ptr<LifetimeBoundCtor> create_target(const MyObj& obj) { // expected-warning {{parameter in intra-TU function should be marked [[clang::lifetimebound]]}}
+ return std::make_unique<LifetimeBoundCtor>(obj); // expected-note {{param returned here}}
+}
+
+void test_inference() {
+ std::unique_ptr<LifetimeBoundCtor> ptr;
+ {
+ MyObj obj;
+ ptr = create_target(obj); // expected-warning {{object whose reference is captured does not live long enough}}
+ } // expected-note {{destroyed here}}
+ (void)ptr; // expected-note {{later used here}}
+}
+} // namespace make_unique_suggestion
>From 954c2bf91d182b2f3aa4f2ac28e7d9ee5221d6ad Mon Sep 17 00:00:00 2001
From: Utkarsh Saxena <usx at google.com>
Date: Sat, 11 Apr 2026 14:47:51 +0000
Subject: [PATCH 6/9] fix suggestions test
---
clang/test/Sema/warn-lifetime-safety-suggestions.cpp | 9 +++++----
clang/test/Sema/warn-lifetime-safety.cpp | 4 ----
2 files changed, 5 insertions(+), 8 deletions(-)
diff --git a/clang/test/Sema/warn-lifetime-safety-suggestions.cpp b/clang/test/Sema/warn-lifetime-safety-suggestions.cpp
index 8db96103b683d..6688d80c8331b 100644
--- a/clang/test/Sema/warn-lifetime-safety-suggestions.cpp
+++ b/clang/test/Sema/warn-lifetime-safety-suggestions.cpp
@@ -1,8 +1,8 @@
// RUN: rm -rf %t
// RUN: split-file %s %t
-// RUN: %clang_cc1 -fsyntax-only -flifetime-safety-inference -fexperimental-lifetime-safety-tu-analysis -Wlifetime-safety-suggestions -Wlifetime-safety -Wno-dangling -I%t -verify %t/test_source.cpp
-// RUN: %clang_cc1 -flifetime-safety-inference -fexperimental-lifetime-safety-tu-analysis -Wlifetime-safety-suggestions -Wlifetime-safety -Wno-dangling -I%t -fixit %t/test_source.cpp
-// RUN: %clang_cc1 -fsyntax-only -flifetime-safety-inference -fexperimental-lifetime-safety-tu-analysis -Wlifetime-safety-suggestions -Wno-dangling -I%t -Werror=lifetime-safety-suggestions %t/test_source.cpp
+// RUN: %clang_cc1 -fsyntax-only -flifetime-safety-inference -fexperimental-lifetime-safety-tu-analysis -Wlifetime-safety-suggestions -Wlifetime-safety -Wno-dangling -I%S -I%t -verify %t/test_source.cpp
+// RUN: %clang_cc1 -flifetime-safety-inference -fexperimental-lifetime-safety-tu-analysis -Wlifetime-safety-suggestions -Wlifetime-safety -Wno-dangling -I%S -I%t -fixit %t/test_source.cpp
+// RUN: %clang_cc1 -fsyntax-only -flifetime-safety-inference -fexperimental-lifetime-safety-tu-analysis -Wlifetime-safety-suggestions -Wno-dangling -I%S -I%t -Werror=lifetime-safety-suggestions %t/test_source.cpp
View definition_before_header(View a);
@@ -10,6 +10,8 @@ View definition_before_header(View a);
#ifndef TEST_HEADER_H
#define TEST_HEADER_H
+#include "Inputs/lifetime-analysis.h"
+
struct View;
struct [[gsl::Owner]] MyObj {
@@ -67,7 +69,6 @@ struct ReturnThisPointer {
//--- test_source.cpp
#include "test_header.h"
-#include "Inputs/lifetime-analysis.h"
View definition_before_header(View a) {
return a; // expected-note {{param returned here}}
diff --git a/clang/test/Sema/warn-lifetime-safety.cpp b/clang/test/Sema/warn-lifetime-safety.cpp
index 31e62cc9f72a5..3d18c48be8d29 100644
--- a/clang/test/Sema/warn-lifetime-safety.cpp
+++ b/clang/test/Sema/warn-lifetime-safety.cpp
@@ -974,8 +974,6 @@ void lifetimebound_make_unique_string_view_local() {
(void)ptr;
}
-
-
struct MultiLifetimeBoundCtor {
MultiLifetimeBoundCtor(const MyObj& obj1 [[clang::lifetimebound]], const MyObj& obj2);
MultiLifetimeBoundCtor(const MyObj& obj1, const MyObj& obj2 [[clang::lifetimebound]], int);
@@ -2507,8 +2505,6 @@ std::string_view return_dangling_view_through_owner() {
return sv; // expected-note {{returned here}}
}
-// FIXME: False negative. Move assignment of unique_ptr is not defaulted,
-// so origins from `local` don't propagate to `ups`.
void owner_outlives_lifetimebound_source() {
std::unique_ptr<S> ups;
{
>From 8a697df3abc31e9e5e1979b9f9b056567665a8d6 Mon Sep 17 00:00:00 2001
From: Utkarsh Saxena <usx at google.com>
Date: Wed, 15 Apr 2026 16:11:01 +0000
Subject: [PATCH 7/9] rebase
---
clang/test/Sema/warn-lifetime-safety-dangling-field.cpp | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/clang/test/Sema/warn-lifetime-safety-dangling-field.cpp b/clang/test/Sema/warn-lifetime-safety-dangling-field.cpp
index 604adfa0c8538..4ed4f535c2ae1 100644
--- a/clang/test/Sema/warn-lifetime-safety-dangling-field.cpp
+++ b/clang/test/Sema/warn-lifetime-safety-dangling-field.cpp
@@ -185,7 +185,7 @@ struct IndirectEscape2 {
}
};
-<<<<<<< HEAD
+
namespace DanglingPointerFieldInBaseClass {
struct BaseWithPointer {
std::string_view view; // expected-note {{this field dangles}}
@@ -197,7 +197,7 @@ struct DerivedWithCtor : BaseWithPointer {
}
};
} // namespace DanglingPointerFieldInBaseClass
-=======
+
namespace MakeUnique {
struct MyObj {};
@@ -213,4 +213,4 @@ struct HasUniquePtrField {
}
};
} // namespace MakeUnique
->>>>>>> 6f5985bd6945 (dangling field)
+
>From bf480da67d50d06997774df7f4e743634e0e6833 Mon Sep 17 00:00:00 2001
From: Utkarsh Saxena <usx at google.com>
Date: Wed, 15 Apr 2026 16:34:18 +0000
Subject: [PATCH 8/9] extract ctor from body in end-of-tu
---
clang/lib/Sema/SemaAttr.cpp | 74 +++++++------------
.../lib/Sema/SemaTemplateInstantiateDecl.cpp | 5 ++
clang/test/Sema/Inputs/lifetime-analysis.h | 12 ++-
clang/test/Sema/warn-lifetime-safety.cpp | 57 +++++++-------
4 files changed, 68 insertions(+), 80 deletions(-)
diff --git a/clang/lib/Sema/SemaAttr.cpp b/clang/lib/Sema/SemaAttr.cpp
index d173b1ba58d8e..ef16cfcfbcdf6 100644
--- a/clang/lib/Sema/SemaAttr.cpp
+++ b/clang/lib/Sema/SemaAttr.cpp
@@ -221,7 +221,19 @@ void Sema::inferGslOwnerPointerAttribute(CXXRecordDecl *Record) {
inferGslPointerAttribute(Record, Record);
}
+static const CXXNewExpr *findCXXNewExpr(const Stmt *S) {
+ if (!S) return nullptr;
+ if (const auto *E = dyn_cast<CXXNewExpr>(S))
+ return E;
+ for (const Stmt *Child : S->children())
+ if (Child)
+ if (const CXXNewExpr *E = findCXXNewExpr(Child))
+ return E;
+ return nullptr;
+}
+
void Sema::inferLifetimeBoundAttribute(FunctionDecl *FD) {
+ llvm::errs() << "JETSKI: inferLifetimeBoundAttribute for " << FD->getNameAsString() << "\n";
if (FD->getNumParams() == 0)
return;
// Skip void returning functions (except constructors). This can occur in
@@ -252,56 +264,20 @@ void Sema::inferLifetimeBoundAttribute(FunctionDecl *FD) {
}
// Handle std::make_unique to propagate lifetimebound attributes from the
- // constructed type's constructor to make_unique's parameters.
- if (FD->isInStdNamespace() && FD->getDeclName().isIdentifier() &&
+ // constructed type's constructor to make_unique's parameters by looking
+ // into its body.
+ if (FD->getDeclName().isIdentifier() &&
FD->getName() == "make_unique") {
- if (!FD->isFunctionTemplateSpecialization())
- return;
-
- const TemplateArgumentList *TAL = FD->getTemplateSpecializationArgs();
- if (!TAL || TAL->size() < 1)
- return;
-
- // make_unique's first template argument is the type being constructed.
- TemplateArgument TA = TAL->get(0);
- if (TA.getKind() != TemplateArgument::Type)
- return;
-
- QualType T = TA.getAsType();
- const auto *RD = T->getAsCXXRecordDecl();
- if (!RD)
- return;
-
- // Find the constructor that matches make_unique's arguments.
- for (const auto *Ctor : RD->ctors()) {
- if (Ctor->getNumParams() != FD->getNumParams())
- continue;
-
- bool Compatible = true;
- for (unsigned i = 0; i < Ctor->getNumParams(); ++i) {
- QualType CtorParamType = Ctor->getParamDecl(i)->getType();
- QualType FDParamType = FD->getParamDecl(i)->getType();
- // Compare types ignoring references.
- if (!Context.hasSameUnqualifiedType(
- CtorParamType.getNonReferenceType(),
- FDParamType.getNonReferenceType())) {
- Compatible = false;
- break;
- }
- }
-
- if (!Compatible)
- continue;
- // Propagate lifetimebound attributes only if the constructor parameter is
- // a reference. This avoids incorrect loan tracking when a by-value view
- // (like string_view) is passed by reference to make_unique.
- for (unsigned i = 0; i < Ctor->getNumParams(); ++i)
- if (Ctor->getParamDecl(i)->hasAttr<LifetimeBoundAttr>() &&
- Ctor->getParamDecl(i)->getType()->isReferenceType())
- FD->getParamDecl(i)->addAttr(
- LifetimeBoundAttr::CreateImplicit(Context, FD->getLocation()));
- break; // Found matching constructor, done.
- }
+ const FunctionDecl *BodyDecl = nullptr;
+ if (FD->getBody(BodyDecl))
+ if (const CXXNewExpr *NewExpr = findCXXNewExpr(BodyDecl->getBody()))
+ if (const CXXConstructExpr *ConstructExpr = NewExpr->getConstructExpr())
+ if (const CXXConstructorDecl *Ctor = ConstructExpr->getConstructor())
+ for (unsigned i = 0; i < Ctor->getNumParams(); ++i)
+ if (Ctor->getParamDecl(i)->hasAttr<LifetimeBoundAttr>() &&
+ i < FD->getNumParams())
+ FD->getParamDecl(i)->addAttr(
+ LifetimeBoundAttr::CreateImplicit(Context, FD->getLocation()));
return;
}
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 954160d4112a5..6158f05bdba61 100644
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -5552,6 +5552,8 @@ void Sema::InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
if (Function->isInvalidDecl() || isa<CXXDeductionGuideDecl>(Function))
return;
+
+
// Never instantiate an explicit specialization except if it is a class scope
// explicit specialization.
TemplateSpecializationKind TSK =
@@ -5969,6 +5971,9 @@ void Sema::InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
// context seems wrong. Investigate more.
ActOnFinishFunctionBody(Function, Body.get(), /*IsInstantiation=*/true);
+
+ inferLifetimeBoundAttribute(Function);
+
checkReferenceToTULocalFromOtherTU(Function, PointOfInstantiation);
if (PatternDecl->isDependentContext())
diff --git a/clang/test/Sema/Inputs/lifetime-analysis.h b/clang/test/Sema/Inputs/lifetime-analysis.h
index 67e6c0f18de5c..788a4ba104af3 100644
--- a/clang/test/Sema/Inputs/lifetime-analysis.h
+++ b/clang/test/Sema/Inputs/lifetime-analysis.h
@@ -194,8 +194,9 @@ struct basic_string {
using string = basic_string<char>;
template<typename T>
-struct unique_ptr {
+struct [[gsl::Owner]] unique_ptr {
unique_ptr();
+ explicit unique_ptr(T*);
unique_ptr(unique_ptr<T>&&);
unique_ptr& operator=(unique_ptr<T>&&);
~unique_ptr();
@@ -205,8 +206,15 @@ struct unique_ptr {
T *get() const;
};
+#ifdef WITH_LIFETIME_SAFETY_BODY
template<typename T, typename... Args>
-unique_ptr<T> make_unique(Args&&... args);
+unique_ptr<T> make_unique(Args&&... args) {
+ return unique_ptr<T>(new T(args...));
+}
+#else
+template<typename T, typename... Args>
+unique_ptr<T> make_unique(Args&&... args [[clang::lifetimebound]]);
+#endif
template<typename T>
struct optional {
diff --git a/clang/test/Sema/warn-lifetime-safety.cpp b/clang/test/Sema/warn-lifetime-safety.cpp
index 3d18c48be8d29..b1ad35cbc8da2 100644
--- a/clang/test/Sema/warn-lifetime-safety.cpp
+++ b/clang/test/Sema/warn-lifetime-safety.cpp
@@ -1,6 +1,6 @@
-// RUN: %clang_cc1 -fsyntax-only -Wlifetime-safety -Wno-dangling -verify=expected,function %s
-// RUN: %clang_cc1 -fsyntax-only -flifetime-safety-inference -fexperimental-lifetime-safety-tu-analysis -Wlifetime-safety -Wno-dangling -verify=expected,tu %s
-// RUN: %clang_cc1 -fsyntax-only -Wlifetime-safety -Wno-dangling -fcxx-exceptions -verify=expected,function %s
+// RUN: %clang_cc1 -fsyntax-only -Wlifetime-safety -Wno-dangling -DWITH_LIFETIME_SAFETY_BODY -verify=expected,function %s
+// RUN: %clang_cc1 -fsyntax-only -flifetime-safety-inference -fexperimental-lifetime-safety-tu-analysis -Wlifetime-safety -Wno-dangling -DWITH_LIFETIME_SAFETY_BODY -verify=expected,tu %s
+// RUN: %clang_cc1 -fsyntax-only -Wlifetime-safety -Wno-dangling -fcxx-exceptions -DWITH_LIFETIME_SAFETY_BODY -verify=expected,function %s
#include "Inputs/lifetime-analysis.h"
@@ -926,6 +926,7 @@ struct LifetimeBoundCtor {
LifetimeBoundCtor();
LifetimeBoundCtor(const MyObj& obj [[clang::lifetimebound]]);
LifetimeBoundCtor(int* p [[clang::lifetimebound]]);
+ LifetimeBoundCtor(std::string_view sv [[clang::lifetimebound]]);
};
void lifetimebound_ctor() {
@@ -941,15 +942,15 @@ void lifetimebound_make_unique() {
std::unique_ptr<LifetimeBoundCtor> ptr;
{
MyObj obj;
- ptr = std::make_unique<LifetimeBoundCtor>(obj); // expected-warning {{object whose reference is captured does not live long enough}}
- } // expected-note {{destroyed here}}
- (void)ptr; // expected-note {{later used here}}
+ ptr = std::make_unique<LifetimeBoundCtor>(obj); // tu-warning {{object whose reference is captured does not live long enough}}
+ } // tu-note {{destroyed here}}
+ (void)ptr; // tu-note {{later used here}}
}
void lifetimebound_make_unique_temp() {
- std::unique_ptr<LifetimeBoundCtor> ptr = std::make_unique<LifetimeBoundCtor>(MyObj()); // expected-warning {{object whose reference is captured does not live long enough}} \
- // expected-note {{destroyed here}}
- (void)ptr; // expected-note {{later used here}}
+ std::unique_ptr<LifetimeBoundCtor> ptr = std::make_unique<LifetimeBoundCtor>(MyObj()); // tu-warning {{object whose reference is captured does not live long enough}} \
+ // tu-note {{destroyed here}}
+ (void)ptr; // tu-note {{later used here}}
}
void lifetimebound_make_unique_raw_ptr() {
@@ -957,10 +958,9 @@ void lifetimebound_make_unique_raw_ptr() {
int x = 0;
{
int* p = &x;
- // FIXME: No warning expected with current implementation
- ptr = std::make_unique<LifetimeBoundCtor>(p);
- }
- (void)ptr;
+ ptr = std::make_unique<LifetimeBoundCtor>(p); // tu-warning {{object whose reference is captured does not live long enough}}
+ } // tu-note {{destroyed here}}
+ (void)ptr; // tu-note {{later used here}}
}
void lifetimebound_make_unique_string_view_local() {
@@ -968,10 +968,9 @@ void lifetimebound_make_unique_string_view_local() {
{
std::string s;
std::string_view sv(s);
- // FIXME: No warning expected with current implementation because of reference mismatch
- ptr = std::make_unique<LifetimeBoundCtor>(sv);
- }
- (void)ptr;
+ ptr = std::make_unique<LifetimeBoundCtor>(sv); // tu-warning {{object whose reference is captured does not live long enough}}
+ } // tu-note {{destroyed here}}
+ (void)ptr; // tu-note {{later used here}}
}
struct MultiLifetimeBoundCtor {
@@ -985,9 +984,9 @@ void lifetimebound_make_unique_multi_params() {
MyObj obj_long;
{
MyObj obj_short;
- ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_short, obj_long); // expected-warning {{object whose reference is captured does not live long enough}}
- } // expected-note {{destroyed here}}
- (void)ptr; // expected-note {{later used here}}
+ ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_short, obj_long); // tu-warning {{object whose reference is captured does not live long enough}}
+ } // tu-note {{destroyed here}}
+ (void)ptr; // tu-note {{later used here}}
}
void lifetimebound_make_unique_multi_params2() {
@@ -995,9 +994,9 @@ void lifetimebound_make_unique_multi_params2() {
MyObj obj_long;
{
MyObj obj_short;
- ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_long, obj_short, 1); // expected-warning {{object whose reference is captured does not live long enough}}
- } // expected-note {{destroyed here}}
- (void)ptr; // expected-note {{later used here}}
+ ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_long, obj_short, 1); // tu-warning {{object whose reference is captured does not live long enough}}
+ } // tu-note {{destroyed here}}
+ (void)ptr; // tu-note {{later used here}}
}
void lifetimebound_make_unique_multi_params3_1() {
@@ -1005,9 +1004,9 @@ void lifetimebound_make_unique_multi_params3_1() {
MyObj obj_long;
{
MyObj obj_short;
- ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_short, obj_long, 1.0); // expected-warning {{object whose reference is captured does not live long enough}}
- } // expected-note {{destroyed here}}
- (void)ptr; // expected-note {{later used here}}
+ ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_short, obj_long, 1.0); // tu-warning {{object whose reference is captured does not live long enough}}
+ } // tu-note {{destroyed here}}
+ (void)ptr; // tu-note {{later used here}}
}
void lifetimebound_make_unique_multi_params3_2() {
@@ -1015,9 +1014,9 @@ void lifetimebound_make_unique_multi_params3_2() {
MyObj obj_long;
{
MyObj obj_short;
- ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_long, obj_short, 1.0); // expected-warning {{object whose reference is captured does not live long enough}}
- } // expected-note {{destroyed here}}
- (void)ptr; // expected-note {{later used here}}
+ ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_long, obj_short, 1.0); // tu-warning {{object whose reference is captured does not live long enough}}
+ } // tu-note {{destroyed here}}
+ (void)ptr; // tu-note {{later used here}}
}
>From 63f48f4baabe001a6508e6376e26a9a7bf99f38c Mon Sep 17 00:00:00 2001
From: Utkarsh Saxena <usx at google.com>
Date: Wed, 15 Apr 2026 17:46:36 +0000
Subject: [PATCH 9/9] extract ctor from CXXNew
---
clang/lib/Sema/SemaAttr.cpp | 61 ++++++++++++++++--------
clang/test/Sema/warn-lifetime-safety.cpp | 48 +++++++++----------
2 files changed, 65 insertions(+), 44 deletions(-)
diff --git a/clang/lib/Sema/SemaAttr.cpp b/clang/lib/Sema/SemaAttr.cpp
index ef16cfcfbcdf6..b4d457c4d06b5 100644
--- a/clang/lib/Sema/SemaAttr.cpp
+++ b/clang/lib/Sema/SemaAttr.cpp
@@ -19,6 +19,7 @@
#include "clang/Basic/TargetInfo.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Sema/Lookup.h"
+#include "clang/Sema/Initialization.h"
#include <optional>
using namespace clang;
@@ -221,19 +222,8 @@ void Sema::inferGslOwnerPointerAttribute(CXXRecordDecl *Record) {
inferGslPointerAttribute(Record, Record);
}
-static const CXXNewExpr *findCXXNewExpr(const Stmt *S) {
- if (!S) return nullptr;
- if (const auto *E = dyn_cast<CXXNewExpr>(S))
- return E;
- for (const Stmt *Child : S->children())
- if (Child)
- if (const CXXNewExpr *E = findCXXNewExpr(Child))
- return E;
- return nullptr;
-}
void Sema::inferLifetimeBoundAttribute(FunctionDecl *FD) {
- llvm::errs() << "JETSKI: inferLifetimeBoundAttribute for " << FD->getNameAsString() << "\n";
if (FD->getNumParams() == 0)
return;
// Skip void returning functions (except constructors). This can occur in
@@ -264,20 +254,51 @@ void Sema::inferLifetimeBoundAttribute(FunctionDecl *FD) {
}
// Handle std::make_unique to propagate lifetimebound attributes from the
- // constructed type's constructor to make_unique's parameters by looking
- // into its body.
+ // constructed type's constructor to make_unique's parameters by performing
+ // constructor lookup.
if (FD->getDeclName().isIdentifier() &&
FD->getName() == "make_unique") {
- const FunctionDecl *BodyDecl = nullptr;
- if (FD->getBody(BodyDecl))
- if (const CXXNewExpr *NewExpr = findCXXNewExpr(BodyDecl->getBody()))
- if (const CXXConstructExpr *ConstructExpr = NewExpr->getConstructExpr())
- if (const CXXConstructorDecl *Ctor = ConstructExpr->getConstructor())
- for (unsigned i = 0; i < Ctor->getNumParams(); ++i)
+ QualType ReturnType = FD->getReturnType();
+ const auto *RT = ReturnType->getAs<RecordType>();
+ if (!RT) return;
+ const auto *Spec = dyn_cast<ClassTemplateSpecializationDecl>(RT->getDecl());
+ if (!Spec) return;
+ if (Spec->getTemplateArgs().size() == 0) return;
+ QualType T = Spec->getTemplateArgs()[0].getAsType();
+
+ SmallVector<Expr *, 4> Args;
+ for (auto *Parm : FD->parameters()) {
+ QualType ParmTy = Parm->getType();
+ ExprValueKind VK = VK_LValue;
+ QualType ArgTy = ParmTy;
+ if (const auto *RefTy = ParmTy->getAs<ReferenceType>()) {
+ ArgTy = RefTy->getPointeeType();
+ if (ParmTy->isRValueReferenceType())
+ VK = VK_XValue;
+ }
+ Args.push_back(new (Context) OpaqueValueExpr(FD->getLocation(), ArgTy, VK));
+ }
+
+ InitializedEntity Entity = InitializedEntity::InitializeTemporary(T);
+ InitializationKind Kind = InitializationKind::CreateDirect(FD->getLocation(), FD->getLocation(), FD->getLocation());
+ InitializationSequence InitSeq(*this, Entity, Kind, Args);
+
+ if (InitSeq) {
+ for (const auto &Step : InitSeq.steps()) {
+ if (Step.Kind == InitializationSequence::SK_ConstructorInitialization) {
+ if (const auto *Ctor = dyn_cast_or_null<CXXConstructorDecl>(Step.Function.Function)) {
+ for (unsigned i = 0; i < Ctor->getNumParams(); ++i) {
if (Ctor->getParamDecl(i)->hasAttr<LifetimeBoundAttr>() &&
- i < FD->getNumParams())
+ i < FD->getNumParams()) {
FD->getParamDecl(i)->addAttr(
LifetimeBoundAttr::CreateImplicit(Context, FD->getLocation()));
+ }
+ }
+ }
+ break;
+ }
+ }
+ }
return;
}
diff --git a/clang/test/Sema/warn-lifetime-safety.cpp b/clang/test/Sema/warn-lifetime-safety.cpp
index b1ad35cbc8da2..ba2747e07f4dd 100644
--- a/clang/test/Sema/warn-lifetime-safety.cpp
+++ b/clang/test/Sema/warn-lifetime-safety.cpp
@@ -942,15 +942,15 @@ void lifetimebound_make_unique() {
std::unique_ptr<LifetimeBoundCtor> ptr;
{
MyObj obj;
- ptr = std::make_unique<LifetimeBoundCtor>(obj); // tu-warning {{object whose reference is captured does not live long enough}}
- } // tu-note {{destroyed here}}
- (void)ptr; // tu-note {{later used here}}
+ ptr = std::make_unique<LifetimeBoundCtor>(obj); // expected-warning {{object whose reference is captured does not live long enough}}
+ } // expected-note {{destroyed here}}
+ (void)ptr; // expected-note {{later used here}}
}
void lifetimebound_make_unique_temp() {
- std::unique_ptr<LifetimeBoundCtor> ptr = std::make_unique<LifetimeBoundCtor>(MyObj()); // tu-warning {{object whose reference is captured does not live long enough}} \
- // tu-note {{destroyed here}}
- (void)ptr; // tu-note {{later used here}}
+ std::unique_ptr<LifetimeBoundCtor> ptr = std::make_unique<LifetimeBoundCtor>(MyObj()); // expected-warning {{object whose reference is captured does not live long enough}} \
+ // expected-note {{destroyed here}}
+ (void)ptr; // expected-note {{later used here}}
}
void lifetimebound_make_unique_raw_ptr() {
@@ -958,9 +958,9 @@ void lifetimebound_make_unique_raw_ptr() {
int x = 0;
{
int* p = &x;
- ptr = std::make_unique<LifetimeBoundCtor>(p); // tu-warning {{object whose reference is captured does not live long enough}}
- } // tu-note {{destroyed here}}
- (void)ptr; // tu-note {{later used here}}
+ ptr = std::make_unique<LifetimeBoundCtor>(p); // expected-warning {{object whose reference is captured does not live long enough}}
+ } // expected-note {{destroyed here}}
+ (void)ptr; // expected-note {{later used here}}
}
void lifetimebound_make_unique_string_view_local() {
@@ -968,9 +968,9 @@ void lifetimebound_make_unique_string_view_local() {
{
std::string s;
std::string_view sv(s);
- ptr = std::make_unique<LifetimeBoundCtor>(sv); // tu-warning {{object whose reference is captured does not live long enough}}
- } // tu-note {{destroyed here}}
- (void)ptr; // tu-note {{later used here}}
+ ptr = std::make_unique<LifetimeBoundCtor>(sv); // expected-warning {{object whose reference is captured does not live long enough}}
+ } // expected-note {{destroyed here}}
+ (void)ptr; // expected-note {{later used here}}
}
struct MultiLifetimeBoundCtor {
@@ -984,9 +984,9 @@ void lifetimebound_make_unique_multi_params() {
MyObj obj_long;
{
MyObj obj_short;
- ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_short, obj_long); // tu-warning {{object whose reference is captured does not live long enough}}
- } // tu-note {{destroyed here}}
- (void)ptr; // tu-note {{later used here}}
+ ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_short, obj_long); // expected-warning {{object whose reference is captured does not live long enough}}
+ } // expected-note {{destroyed here}}
+ (void)ptr; // expected-note {{later used here}}
}
void lifetimebound_make_unique_multi_params2() {
@@ -994,9 +994,9 @@ void lifetimebound_make_unique_multi_params2() {
MyObj obj_long;
{
MyObj obj_short;
- ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_long, obj_short, 1); // tu-warning {{object whose reference is captured does not live long enough}}
- } // tu-note {{destroyed here}}
- (void)ptr; // tu-note {{later used here}}
+ ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_long, obj_short, 1); // expected-warning {{object whose reference is captured does not live long enough}}
+ } // expected-note {{destroyed here}}
+ (void)ptr; // expected-note {{later used here}}
}
void lifetimebound_make_unique_multi_params3_1() {
@@ -1004,9 +1004,9 @@ void lifetimebound_make_unique_multi_params3_1() {
MyObj obj_long;
{
MyObj obj_short;
- ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_short, obj_long, 1.0); // tu-warning {{object whose reference is captured does not live long enough}}
- } // tu-note {{destroyed here}}
- (void)ptr; // tu-note {{later used here}}
+ ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_short, obj_long, 1.0); // expected-warning {{object whose reference is captured does not live long enough}}
+ } // expected-note {{destroyed here}}
+ (void)ptr; // expected-note {{later used here}}
}
void lifetimebound_make_unique_multi_params3_2() {
@@ -1014,9 +1014,9 @@ void lifetimebound_make_unique_multi_params3_2() {
MyObj obj_long;
{
MyObj obj_short;
- ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_long, obj_short, 1.0); // tu-warning {{object whose reference is captured does not live long enough}}
- } // tu-note {{destroyed here}}
- (void)ptr; // tu-note {{later used here}}
+ ptr = std::make_unique<MultiLifetimeBoundCtor>(obj_long, obj_short, 1.0); // expected-warning {{object whose reference is captured does not live long enough}}
+ } // expected-note {{destroyed here}}
+ (void)ptr; // expected-note {{later used here}}
}
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