Fix "use of memory after freed" warning.

Static analyzer gets confused in the code to free a linked list.
To avoid confusion add an "assert" to tell the analyzer there is no
alias between the memory being deleted and accessed.

Bug: b/27101951
Test: Warning is gone.
Change-Id: Ia6661ee76908c2025b5e1a764d25ba3e11bf44c8

1 files changed, 9 insertions, 1 deletions

diff --git a/libs/binder/MemoryDealer.cpp b/libs/binder/MemoryDealer.cpp
index 2a15773aa3..1cfe02a3fe 100644
--- a/libs/binder/MemoryDealer.cpp
+++ b/libs/binder/MemoryDealer.cpp
@@ -289,7 +289,15 @@ SimpleBestFitAllocator::SimpleBestFitAllocator(size_t size)
 SimpleBestFitAllocator::~SimpleBestFitAllocator()
 {
     while(!mList.isEmpty()) {
-        delete mList.remove(mList.head());
+        chunk_t* removed = mList.remove(mList.head());
+#ifdef __clang_analyzer__
+        // Clang static analyzer gets confused in this loop
+        // and generates a false positive warning about accessing
+        // memory that is already freed.
+        // Add an "assert" to avoid the confusion.
+        LOG_ALWAYS_FATAL_IF(mList.head() == removed);
+#endif
+        delete removed;
     }
 }