[LifetimeSafety] Introduce intra-procedural analysis in Clang

clang/include/clang/Analysis/Analyses/LifetimeSafety.h

@@ -0,0 +1,30 @@
+//===- LifetimeSafety.h - C++ Lifetime Safety Analysis -*----------- C++-*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines the entry point for a dataflow-based static analysis
+// that checks for C++ lifetime violations.
+//
+// The analysis is based on the concepts of "origins" and "loans" to track
+// pointer lifetimes and detect issues like use-after-free and dangling
+// pointers. See the RFC for more details:
+// https://discourse.llvm.org/t/rfc-intra-procedural-lifetime-analysis-in-clang/86291
+//
+//===----------------------------------------------------------------------===//
+#ifndef LLVM_CLANG_ANALYSIS_ANALYSES_LIFETIMESAFETY_H
+#define LLVM_CLANG_ANALYSIS_ANALYSES_LIFETIMESAFETY_H
+#include "clang/AST/DeclBase.h"
+#include "clang/Analysis/AnalysisDeclContext.h"
+#include "clang/Analysis/CFG.h"
+namespace clang {
+
+void runLifetimeSafetyAnalysis(const DeclContext &DC, const CFG &Cfg,
+                               AnalysisDeclContext &AC);
+
+} // namespace clang
+
+#endif // LLVM_CLANG_ANALYSIS_ANALYSES_LIFETIMESAFETY_H

clang/include/clang/Basic/DiagnosticGroups.td

@@ -532,6 +532,9 @@ def Dangling : DiagGroup<"dangling", [DanglingAssignment,
                                       DanglingInitializerList,
                                       DanglingGsl,
                                       ReturnStackAddress]>;
+
+def LifetimeSafety : DiagGroup<"experimental-lifetime-safety">;
+
 def DistributedObjectModifiers : DiagGroup<"distributed-object-modifiers">;
 def DllexportExplicitInstantiationDecl : DiagGroup<"dllexport-explicit-instantiation-decl">;
 def ExcessInitializers : DiagGroup<"excess-initializers">;

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -10622,6 +10622,10 @@ def warn_dangling_reference_captured_by_unknown : Warning<
    "object whose reference is captured will be destroyed at the end of "
    "the full-expression">, InGroup<DanglingCapture>;
 
+def warn_experimental_lifetime_safety_dummy_warning : Warning<
+   "todo: remove this warning after we have atleast one warning based on the lifetime analysis">, 
+   InGroup<LifetimeSafety>, DefaultIgnore;
+
 // For non-floating point, expressions of the form x == x or x != x
 // should result in a warning, since these always evaluate to a constant.
 // Array comparisons have similar warnings

clang/lib/Analysis/CMakeLists.txt

@@ -21,6 +21,7 @@ add_clang_library(clangAnalysis
   FixitUtil.cpp
   IntervalPartition.cpp
   IssueHash.cpp
+  LifetimeSafety.cpp
   LiveVariables.cpp
   MacroExpansionContext.cpp
   ObjCNoReturn.cpp