Fix PR 4230: Don't flag leaks of NSAutoreleasePools until we know that we aren' at the top-most scope of autorelease pools.

llvm-svn: 72065

clang/lib/Analysis/CFRefCount.cpp

@@ -1439,6 +1439,10 @@ void RetainSummaryManager::InitializeMethodSummaries() {
                      "styleMask", "backing", "defer", "screen", NULL);
 #endif
   
+  // Don't track allocated autorelease pools yet, as it is okay to prematurely
+  // exit a method.
+  addClassMethSummary("NSAutoreleasePool", "alloc", NoTrackYet);
+
   // Create NSAssertionHandler summaries.
   addPanicSummary("NSAssertionHandler", "handleFailureInFunction", "file",
                   "lineNumber", "description", NULL); 

clang/test/Analysis/retain-release.m

@@ -618,6 +618,18 @@ void test_RDar6859457(RDar6859457 *x, void *bytes, NSUInteger dataLength) {
   [NSData dataWithBytesNoCopy:bytes length:dataLength freeWhenDone:1]; // no-warning
 }
 
+//===----------------------------------------------------------------------===//
+// PR 4230 - an autorelease pool is not necessarily leaked during a premature
+//  return
+//===----------------------------------------------------------------------===//
+
+static void PR4230(void)
+{
+  NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; // no-warning
+  NSString *object = [[[NSString alloc] init] autorelease]; // no-warning
+  return;
+}
+
 //===----------------------------------------------------------------------===//
 // Method name that has a null IdentifierInfo* for its first selector slot.
 // This test just makes sure that we handle it.