Avoid calling memcpy with NULL pointers #305
Merged
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According to the C/C++ standards, calling
memcpy(NULL, NULL, 0)
is undefined behaviour. Recent GCC versions may rely on this by optimizing NULL pointer checks more aggressively, see [1].This patch tries to avoid calling std::memcpy with zero elements. As a side effect, explicitly return NULL when requesting an empty block from MemoryPoolAllocator::Malloc.
This may be related to #301. Opening the pull-request as requested by @miloyip.
[1] https://gcc.gnu.org/gcc-4.9/porting_to.html