From: Aaron Puchert <aaronpuchert@alice-dsl.net>
Date: Wed, 19 Sep 2018 00:19:38 +0000 (+0000)
Subject: Thread safety analysis: Fix crash for function pointers
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=4a9b0e9a580ad0b54a646d6fb04eb9b80d7c1a92;p=clang

Thread safety analysis: Fix crash for function pointers

For function pointers, the FunctionDecl of the callee is unknown, so
getDirectCallee will return nullptr. We have to catch that case to avoid
crashing. We assume there is no attribute then.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@342519 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Analysis/ThreadSafetyCommon.cpp b/lib/Analysis/ThreadSafetyCommon.cpp
index fced17ff91..ac765808ce 100644
--- a/lib/Analysis/ThreadSafetyCommon.cpp
+++ b/lib/Analysis/ThreadSafetyCommon.cpp
@@ -354,15 +354,17 @@ til::SExpr *SExprBuilder::translateCallExpr(const CallExpr *CE,
                                             const Expr *SelfE) {
   if (CapabilityExprMode) {
     // Handle LOCK_RETURNED
-    const FunctionDecl *FD = CE->getDirectCallee()->getMostRecentDecl();
-    if (LockReturnedAttr* At = FD->getAttr<LockReturnedAttr>()) {
-      CallingContext LRCallCtx(Ctx);
-      LRCallCtx.AttrDecl = CE->getDirectCallee();
-      LRCallCtx.SelfArg  = SelfE;
-      LRCallCtx.NumArgs  = CE->getNumArgs();
-      LRCallCtx.FunArgs  = CE->getArgs();
-      return const_cast<til::SExpr *>(
-          translateAttrExpr(At->getArg(), &LRCallCtx).sexpr());
+    if (const FunctionDecl *FD = CE->getDirectCallee()) {
+      FD = FD->getMostRecentDecl();
+      if (LockReturnedAttr *At = FD->getAttr<LockReturnedAttr>()) {
+        CallingContext LRCallCtx(Ctx);
+        LRCallCtx.AttrDecl = CE->getDirectCallee();
+        LRCallCtx.SelfArg = SelfE;
+        LRCallCtx.NumArgs = CE->getNumArgs();
+        LRCallCtx.FunArgs = CE->getArgs();
+        return const_cast<til::SExpr *>(
+            translateAttrExpr(At->getArg(), &LRCallCtx).sexpr());
+      }
     }
   }
 
diff --git a/test/SemaCXX/warn-thread-safety-analysis.cpp b/test/SemaCXX/warn-thread-safety-analysis.cpp
index deaa7d12cf..0be2668a48 100644
--- a/test/SemaCXX/warn-thread-safety-analysis.cpp
+++ b/test/SemaCXX/warn-thread-safety-analysis.cpp
@@ -2323,6 +2323,7 @@ Foo& getBarFoo(Bar &bar, int c) { return bar.getFoo2(c); }
 void test() {
   Foo foo;
   Foo *fooArray;
+  Foo &(*fooFuncPtr)();
   Bar bar;
   int a;
   int b;
@@ -2359,6 +2360,10 @@ void test() {
   (a > 0 ? fooArray[1] : fooArray[b]).mu_.Lock();
   (a > 0 ? fooArray[1] : fooArray[b]).a = 0;
   (a > 0 ? fooArray[1] : fooArray[b]).mu_.Unlock();
+
+  fooFuncPtr().mu_.Lock();
+  fooFuncPtr().a = 0;
+  fooFuncPtr().mu_.Unlock();
 }