Avoid allocating memory for empty shared vectors - #21
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This is achieved by having them all share a global immutable header with length and capacity set to zero. This only works with allocators that have nothing to store and nothing to drop, and with items and allocators with an alignment equal or less than 64 bytes. If these requirements are not met, the vector allocates a header of its own.
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This is achieved by having them all share a global immutable header with length and capacity set to zero.
This only works with allocators that have nothing to store and nothing to drop, and with items and allocators with an alignment equal or less than 64 bytes. If these requirements are not met, the vector allocates a header of its own.