r338312 - [analyzer] Fix crash in RunLoopAutoreleaseChecker on empty children

[George Karpenkov via cfe-commits]

Author: george.karpenkov
Date: Mon Jul 30 14:44:15 2018
New Revision: 338312

URL: http://llvm.org/viewvc/llvm-project?rev=338312&view=rev
Log:
[analyzer] Fix crash in RunLoopAutoreleaseChecker on empty children

Differential Revision: https://reviews.llvm.org/D50012

Modified:
    cfe/trunk/lib/StaticAnalyzer/Checkers/RunLoopAutoreleaseLeakChecker.cpp
    cfe/trunk/test/Analysis/Checkers/RunLoopAutoreleaseLeakChecker.m

Modified: cfe/trunk/lib/StaticAnalyzer/Checkers/RunLoopAutoreleaseLeakChecker.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/StaticAnalyzer/Checkers/RunLoopAutoreleaseLeakChecker.cpp?rev=338312&r1=338311&r2=338312&view=diff
==============================================================================
--- cfe/trunk/lib/StaticAnalyzer/Checkers/RunLoopAutoreleaseLeakChecker.cpp (original)
+++ cfe/trunk/lib/StaticAnalyzer/Checkers/RunLoopAutoreleaseLeakChecker.cpp Mon Jul 30 14:44:15 2018
@@ -46,8 +46,7 @@ const char * RunLoopRunBind = "RunLoopRu
 const char * OtherMsgBind = "OtherMessageSentM";
 const char * AutoreleasePoolBind = "AutoreleasePoolM";
 
-class RunLoopAutoreleaseLeakChecker : public Checker<
-                                      check::ASTCodeBody> {
+class RunLoopAutoreleaseLeakChecker : public Checker<check::ASTCodeBody> {
 
 public:
   void checkASTCodeBody(const Decl *D,
@@ -66,6 +65,8 @@ static TriBoolTy
 seenBeforeRec(const Stmt *Parent, const Stmt *A, const Stmt *B,
               MemoizationMapTy &Memoization) {
   for (const Stmt *C : Parent->children()) {
+    if (!C) continue;
+
     if (C == A)
       return true;
 

Modified: cfe/trunk/test/Analysis/Checkers/RunLoopAutoreleaseLeakChecker.m
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Analysis/Checkers/RunLoopAutoreleaseLeakChecker.m?rev=338312&r1=338311&r2=338312&view=diff
==============================================================================
--- cfe/trunk/test/Analysis/Checkers/RunLoopAutoreleaseLeakChecker.m (original)
+++ cfe/trunk/test/Analysis/Checkers/RunLoopAutoreleaseLeakChecker.m Mon Jul 30 14:44:15 2018
@@ -43,7 +43,7 @@ void runloop_init_before_two_objects() {
     NSObject *object2 = [[NSObject alloc] init]; // no-warning, warning on the first one is enough.
     (void) object;
     (void) object2;
-    [[NSRunLoop mainRunLoop] run]; 
+    [[NSRunLoop mainRunLoop] run];
   }
 }
 
@@ -60,6 +60,15 @@ void runloop_init_after() { // No warnin
     (void) object;
   }
 }
+
+void no_crash_on_empty_children() {
+  @autoreleasepool {
+    for (;;) {}
+    NSObject *object = [[NSObject alloc] init]; // expected-warning{{Temporary objects allocated in the autorelease pool followed by the launch of main run loop may never get released; consider moving them to a separate autorelease pool}}
+    [[NSRunLoop mainRunLoop] run];
+    (void) object;
+  }
+}
 
 #endif