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.

llvm-svn: 342519

2 files changed, 16 insertions, 9 deletions

diff --git a/clang/lib/Analysis/ThreadSafetyCommon.cpp b/clang/lib/Analysis/ThreadSafetyCommon.cpp
index fced17ff919..ac765808cea 100644
--- a/clang/lib/Analysis/ThreadSafetyCommon.cpp
+++ b/clang/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/clang/test/SemaCXX/warn-thread-safety-analysis.cpp b/clang/test/SemaCXX/warn-thread-safety-analysis.cpp
index deaa7d12cfb..0be2668a48d 100644
--- a/clang/test/SemaCXX/warn-thread-safety-analysis.cpp
+++ b/clang/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();
 }