Fix a horrible bug in all dataflow analyses that use CFGRecStmtVisitor (including...

We shouldn't recurse into CompoundStmts since they are already inlined in the CFG.  This could result in
bogus dead stores warnings (among other things).

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@117162 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/clang/Analysis/Visitors/CFGRecStmtVisitor.h b/include/clang/Analysis/Visitors/CFGRecStmtVisitor.h
index 75a4ac66012e7adf6d2f4b74f8a13c40860f2fc0..bb7cf0b97e53453c5bff57e822a6c6b28acca339 100644 (file)
--- a/include/clang/Analysis/Visitors/CFGRecStmtVisitor.h
+++ b/include/clang/Analysis/Visitors/CFGRecStmtVisitor.h
@@ -26,6 +26,11 @@ public:
     static_cast< ImplClass* >(this)->VisitChildren(S);
   }
   
+  void VisitCompoundStmt(CompoundStmt *S) {
+    // Do nothing.  Everything in a CompoundStmt is inlined
+    // into the CFG.
+  }
+  
   void VisitConditionVariableInit(Stmt *S) {
     assert(S == this->getCurrentBlkStmt());
     VarDecl *CondVar = 0;

diff --git a/test/Analysis/dead-stores.m b/test/Analysis/dead-stores.m
index 701e5802b25e5f9cc1c1331b43d41a81f299b059..730b8266bd10162a47e5bf80607ce3d76b5aa290 100644 (file)
--- a/test/Analysis/dead-stores.m
+++ b/test/Analysis/dead-stores.m
@@ -41,3 +41,21 @@ void DeadStoreTest(NSObject *anObject) {
 void rdar_7631278(NSObject *x) {
   x = ((void*)0);
 }
+
+// This test case issuing a bogus warning for the declaration of 'isExec'
+// because the compound statement for the @synchronized was being visited
+// twice by the LiveVariables analysis.
+BOOL baz_rdar8527823();
+void foo_rdar8527823();
+@interface RDar8527823
+- (void) bar_rbar8527823;
+@end
+@implementation RDar8527823
+- (void) bar_rbar8527823
+{
+ @synchronized(self) {
+   BOOL isExec = baz_rdar8527823(); // no-warning
+   if (isExec) foo_rdar8527823();
+ }
+}
+@end