Fix issue where moving BitVector could cause free(nullptr)

If one std::move's a BitVector the old BitVector's storage_ will be
nulled and size set to 0. This is fine but when ~BitVector is run the
allocator will be asked to free a nullptr. Since this is generally not
expected by allocators, not supported by some and breaks the movement
semantics of C++ I've changed the behavior to only Free memory
if there is memory to be freed.

Test: ./test.py --host
Change-Id: I2716a604370c94bcea1a0989c5e6b94e45a2b063

1 files changed, 4 insertions, 1 deletions

diff --git a/libartbase/base/bit_vector.cc b/libartbase/base/bit_vector.cc
index b32b4117dd..8e3d4c9bf7 100644
--- a/libartbase/base/bit_vector.cc
+++ b/libartbase/base/bit_vector.cc
@@ -61,7 +61,10 @@ BitVector::BitVector(const BitVector& src,
 }
 
 BitVector::~BitVector() {
-  allocator_->Free(storage_);
+  if (storage_ != nullptr) {
+    // Only free if we haven't been moved out of.
+    allocator_->Free(storage_);
+  }
 }
 
 bool BitVector::SameBitsSet(const BitVector *src) const {