[clang] [Clang]Ensure correct handling of cleanup access control (#135668) (PR #135686)

[Oliver Hunt via cfe-commits]

https://github.com/ojhunt updated https://github.com/llvm/llvm-project/pull/135686

>From 62be33b3aa475a33d1c11679ed069eb2af981754 Mon Sep 17 00:00:00 2001
From: Oliver Hunt <oliver at apple.com>
Date: Mon, 14 Apr 2025 15:02:46 -0700
Subject: [PATCH] [Clang]Ensure correct handling of access control in P2719
 diagnostics (#135668)

The P2719 implementation refactored diagnostics for cleanup delete, and as
part of that I attempted to fix handling of inaccessible cleanup operator
delete. Alas the new branch was incorrect as it was performing an implicit
bool conversion, which resulted in friend accessible cleanup operators
incorrectly being considered erroneous and the allocation path errored out.
This error however did not get diagnosed, so the result was and so we did
not actually error out before codegen.

Added both Sema and CodeGen tests to cover this.
---
 clang/lib/Sema/SemaExprCXX.cpp      |  5 ++--
 clang/test/CodeGenCXX/bug135668.cpp | 38 +++++++++++++++++++++++++++++
 clang/test/SemaCXX/bug135668.cpp    | 25 +++++++++++++++++++
 3 files changed, 66 insertions(+), 2 deletions(-)
 create mode 100644 clang/test/CodeGenCXX/bug135668.cpp
 create mode 100644 clang/test/SemaCXX/bug135668.cpp

diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index 16a39f8b5a4dd..dfb5824a1c3d7 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -1929,8 +1929,9 @@ static bool CheckDeleteOperator(Sema &S, SourceLocation StartLoc,
     }
     return true;
   }
-
-  return S.CheckAllocationAccess(StartLoc, Range, NamingClass, Decl, Diagnose);
+  Sema::AccessResult Accessible =
+      S.CheckAllocationAccess(StartLoc, Range, NamingClass, Decl, Diagnose);
+  return Accessible == Sema::AR_inaccessible;
 }
 
 /// Select the correct "usual" deallocation function to use from a selection of
diff --git a/clang/test/CodeGenCXX/bug135668.cpp b/clang/test/CodeGenCXX/bug135668.cpp
new file mode 100644
index 0000000000000..08743bd36bf5b
--- /dev/null
+++ b/clang/test/CodeGenCXX/bug135668.cpp
@@ -0,0 +1,38 @@
+// RUN: %clang_cc1 %s -triple arm64-apple-macosx -emit-llvm -fcxx-exceptions -fexceptions -std=c++23 -o - | FileCheck  %s
+
+class TestClass {
+  public:
+   TestClass();
+   int field = 0;
+   friend class Foo;
+   static void * operator new(unsigned long size);
+  private:
+   static void operator delete(void *p);
+ };
+
+class Foo {
+public:
+  int test_method();
+};
+
+int Foo::test_method() {
+  TestClass *obj = new TestClass() ;
+  return obj->field;
+}
+
+// CHECK-LABEL: define noundef i32 @_ZN3Foo11test_methodEv
+// CHECK: [[THIS_ADDR:%.*]] = alloca ptr, align 8
+// CHECK: [[OBJ:%.*]] = alloca ptr, align 8
+// CHECK: store ptr %this, ptr [[THIS_ADDR]], align 8
+// CHECK: [[THIS1:%.*]] = load ptr, ptr [[THIS_ADDR]], align 8
+// CHECK: [[ALLOCATION:%.*]] = call noundef ptr @_ZN9TestClassnwEm(i64 noundef 4)
+// CHECK: [[INITIALIZEDOBJ:%.*]] = invoke noundef ptr @_ZN9TestClassC1Ev(ptr noundef nonnull align 4 dereferenceable(4) [[ALLOCATION]])
+// CHECK-NEXT:  to label %[[INVOKE_CONT:.*]] unwind label %[[LPAD:.*]]
+// CHECK: [[INVOKE_CONT]]:
+// CHECK: store ptr [[ALLOCATION]], ptr [[OBJ]], align 8
+// CHECK: [[OBJPTR:%.*]] = load ptr, ptr [[OBJ]], align 8
+// CHECK: [[FIELDPTR:%.*]] = getelementptr inbounds nuw %class.TestClass, ptr [[OBJPTR]], i32 0, i32 0
+// CHECK: [[FIELD:%.*]] = load i32, ptr [[FIELDPTR]], align 4
+// CHECK: ret i32 [[FIELD]]
+// CHECK: [[LPAD]]:
+// CHECK: call void @_ZN9TestClassdlEPv(ptr noundef [[ALLOCATION]]) #3
diff --git a/clang/test/SemaCXX/bug135668.cpp b/clang/test/SemaCXX/bug135668.cpp
new file mode 100644
index 0000000000000..96d3d4abfd3ef
--- /dev/null
+++ b/clang/test/SemaCXX/bug135668.cpp
@@ -0,0 +1,25 @@
+// RUN: %clang_cc1 -triple arm64-apple-macosx -Wall -fsyntax-only -verify %s -std=c++26 -fexceptions -fcxx-exceptions
+// expected-no-diagnostics
+
+// This test makes sure that we don't erroneously consider an accessible operator
+// delete to be inaccessible, and then discard the entire new expression.
+
+class TestClass {
+public:
+  TestClass();
+  int field = 0;
+  friend class Foo;
+  static void * operator new(unsigned long size);
+private:
+  static void operator delete(void *p);
+};
+
+class Foo {
+public:
+  int test_method();
+};
+
+int Foo::test_method() {
+  TestClass *obj = new TestClass() ;
+  return obj->field;
+}