[analyzer] RetainCount: Suppress retain detection heuristic on some CM methods.

If it ends with "Retain" like CFRetain and returns a CFTypeRef like CFRetain,
then it is not necessarily a CFRetain. But it is indeed true that these two
return something retained.

Differential Revision: https://reviews.llvm.org/D55907

rdar://problem/39390714

llvm-svn: 349862

1 files changed, 11 insertions, 0 deletions

diff --git a/clang/lib/StaticAnalyzer/Core/RetainSummaryManager.cpp b/clang/lib/StaticAnalyzer/Core/RetainSummaryManager.cpp
index 3bbb4c7..0187eba 100644
--- a/clang/lib/StaticAnalyzer/Core/RetainSummaryManager.cpp
+++ b/clang/lib/StaticAnalyzer/Core/RetainSummaryManager.cpp
@@ -204,6 +204,11 @@ const RetainSummary *RetainSummaryManager::getSummaryForObjCOrCFObject(
     AllowAnnotations = false;
     return RetTy->isObjCIdType() ? getUnarySummary(FT, cfmakecollectable)
                                  : getPersistentStopSummary();
+  } else if (FName == "CMBufferQueueDequeueAndRetain" ||
+             FName == "CMBufferQueueDequeueIfDataReadyAndRetain") {
+    // Part of: <rdar://problem/39390714>.
+    return getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF), DoNothing,
+                                DoNothing);
   } else if (FName == "CFPlugInInstanceCreate") {
     return getPersistentSummary(RetEffect::MakeNoRet());
   } else if (FName == "IORegistryEntrySearchCFProperty" ||
@@ -591,6 +596,12 @@ RetainSummaryManager::canEval(const CallExpr *CE, const FunctionDecl *FD,
     // Handle: (CF|CG|CV)Retain
     //         CFAutorelease
     // It's okay to be a little sloppy here.
+    if (FName == "CMBufferQueueDequeueAndRetain" ||
+        FName == "CMBufferQueueDequeueIfDataReadyAndRetain") {
+      // Part of: <rdar://problem/39390714>.
+      // These are not retain. They just return something and retain it.
+      return None;
+    }
     if (cocoa::isRefType(ResultTy, "CF", FName) ||
         cocoa::isRefType(ResultTy, "CG", FName) ||
         cocoa::isRefType(ResultTy, "CV", FName))