[PATCH] D39888: [lsan] Only use VM_MEMORY_OS_ALLOC_ONCE on Darwin versions that support it

[Rainer Orth via Phabricator via llvm-commits]

ro added a comment.

In https://reviews.llvm.org/D39888#924761, @kubamracek wrote:

> If the only problem here is that `VM_MEMORY_OS_ALLOC_ONCE` is not defined in older SDKs, then I suggest to simply copy the definition from the header and define something like `kSanitizerVmMemoryOsAllocOnce` ourselves (and add an explaining comment, of course). We certainly did that in other parts to avoid depending on the SDK.


But what does this buy us?  AFAICS, the underlying functionality only appeared in OS X 10.9 and no way/amount of providing the macros
will introduce the kernel side of that.


https://reviews.llvm.org/D39888