Is the C++ `free` function thread-safe?

Question

That is, if my C++ application allocates memory in one thread using malloc, will free successfully de-allocate the memory, if called from another thread, or can I expect it to throw an exception? Both threads belong to the same process. I am using Visual Studio 2008. Thanks.

Answer 1

The current standard doesn't make any guarantees about threads. On most implementations, malloc and free may be called from different threads. Visual C++ heap code also serializes access to heaps, so you should be fine.