Do not reallocate on sizehint to same size #49703
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The sizehint! code currently do not reallocate when sizehinting to a smaller size if 1/8th or fewer elements will be freed. However, the check rounds down, so an array of size e.g. 3 resized to size 3 will "free" 1/8th of the elements, namely zero elements, needlessly resizing. This commit changes the check to only reallocate if MORE than 1/8th of elements will be freed.
oscardssmith
approved these changes
May 9, 2023
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The sizehint! code currently do not reallocate when sizehinting to a smaller size if 1/8th or fewer elements will be freed. However, the check rounds down, so an array of size e.g. 3 resized to size 3 will "free" 1/8th of the elements, namely zero elements, needlessly resizing.
This commit changes the check to only reallocate if MORE than 1/8th of elements will be freed.
Close #49695