r342519 - Thread safety analysis: Fix crash for function pointers

[Aaron Puchert via cfe-commits]

Author: aaronpuchert
Date: Tue Sep 18 17:19:38 2018
New Revision: 342519

URL: http://llvm.org/viewvc/llvm-project?rev=342519&view=rev
Log:
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.

Modified:
    cfe/trunk/lib/Analysis/ThreadSafetyCommon.cpp
    cfe/trunk/test/SemaCXX/warn-thread-safety-analysis.cpp

Modified: cfe/trunk/lib/Analysis/ThreadSafetyCommon.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Analysis/ThreadSafetyCommon.cpp?rev=342519&r1=342518&r2=342519&view=diff
==============================================================================
--- cfe/trunk/lib/Analysis/ThreadSafetyCommon.cpp (original)
+++ cfe/trunk/lib/Analysis/ThreadSafetyCommon.cpp Tue Sep 18 17:19:38 2018
@@ -354,15 +354,17 @@ til::SExpr *SExprBuilder::translateCallE
                                             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());
+      }
     }
   }
 

Modified: cfe/trunk/test/SemaCXX/warn-thread-safety-analysis.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/warn-thread-safety-analysis.cpp?rev=342519&r1=342518&r2=342519&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/warn-thread-safety-analysis.cpp (original)
+++ cfe/trunk/test/SemaCXX/warn-thread-safety-analysis.cpp Tue Sep 18 17:19:38 2018
@@ -2323,6 +2323,7 @@ Foo& getBarFoo(Bar &bar, int c) { return
 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();
 }