From 2a02f4d535ddae30898f013649d8c1902082921c Mon Sep 17 00:00:00 2001
From: Pavel Labath <labath@google.com>
Date: Wed, 3 Jul 2013 08:23:49 +0000
Subject: [PATCH] [analyzer] Improve handling of noreturn destructors

Summary:
The analyzer incorrectly handled noreturn destructors which were hidden inside
function calls. This happened because NoReturnFunctionChecker only listened for
PostStmt events, which are not executed for destructor calls. I've changed it to
listen to PostCall events, which should catch both cases.

Reviewers: jordan_rose

CC: cfe-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D1056

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@185522 91177308-0d34-0410-b5e6-96231b3b80d8
---
 .../Checkers/NoReturnFunctionChecker.cpp      | 24 +++++++++----------
 test/Analysis/dtor.cpp                        | 16 +++++++++++++
 2 files changed, 27 insertions(+), 13 deletions(-)

diff --git a/lib/StaticAnalyzer/Checkers/NoReturnFunctionChecker.cpp b/lib/StaticAnalyzer/Checkers/NoReturnFunctionChecker.cpp
index 0009e1b7cf..d7a880c660 100644
--- a/lib/StaticAnalyzer/Checkers/NoReturnFunctionChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/NoReturnFunctionChecker.cpp
@@ -26,31 +26,29 @@ using namespace ento;
 
 namespace {
 
-class NoReturnFunctionChecker : public Checker< check::PostStmt<CallExpr>,
+class NoReturnFunctionChecker : public Checker< check::PostCall,
                                                 check::PostObjCMessage > {
 public:
-  void checkPostStmt(const CallExpr *CE, CheckerContext &C) const;
+  void checkPostCall(const CallEvent &CE, CheckerContext &C) const;
   void checkPostObjCMessage(const ObjCMethodCall &msg, CheckerContext &C) const;
 };
 
 }
 
-void NoReturnFunctionChecker::checkPostStmt(const CallExpr *CE,
+void NoReturnFunctionChecker::checkPostCall(const CallEvent &CE,
                                             CheckerContext &C) const {
   ProgramStateRef state = C.getState();
-  const Expr *Callee = CE->getCallee();
+  bool BuildSinks = false;
 
-  bool BuildSinks = getFunctionExtInfo(Callee->getType()).getNoReturn();
+  if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(CE.getDecl()))
+    BuildSinks = FD->getAttr<AnalyzerNoReturnAttr>() || FD->isNoReturn();
 
-  if (!BuildSinks) {
-    SVal L = state->getSVal(Callee, C.getLocationContext());
-    const FunctionDecl *FD = L.getAsFunctionDecl();
-    if (!FD)
-      return;
+  const Expr *Callee = CE.getOriginExpr();
+  if (!BuildSinks && Callee)
+    BuildSinks = getFunctionExtInfo(Callee->getType()).getNoReturn();
 
-    if (FD->getAttr<AnalyzerNoReturnAttr>() || FD->isNoReturn())
-      BuildSinks = true;
-    else if (const IdentifierInfo *II = FD->getIdentifier()) {
+  if (!BuildSinks && CE.isGlobalCFunction()) {
+    if (const IdentifierInfo *II = CE.getCalleeIdentifier()) {
       // HACK: Some functions are not marked noreturn, and don't return.
       //  Here are a few hardwired ones.  If this takes too long, we can
       //  potentially cache these results.
diff --git a/test/Analysis/dtor.cpp b/test/Analysis/dtor.cpp
index 18cd9853f6..58bdcea631 100644
--- a/test/Analysis/dtor.cpp
+++ b/test/Analysis/dtor.cpp
@@ -401,3 +401,19 @@ namespace LifetimeExtension {
     clang_analyzer_eval(SaveOnVirtualDestruct::lastOutput == 42); // expected-warning{{TRUE}}
   }
 }
+
+namespace NoReturn {
+  struct NR {
+    ~NR() __attribute__((noreturn));
+  };
+
+  void f(int **x) {
+    NR nr;
+  }
+
+  void g() {
+    int *x;
+    f(&x);
+    *x = 47; // no warning
+  }
+}
-- 
2.40.0