Avoid a list/array allocation in Task.WhenAll(enumerable) #110536
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When the incoming enumerable isn't a `Task[]` or `List<Task>`, we end up allocating either a `Task[]` or a `List<T>` (which then may incur one or more array allocations under the covers). We can avoid that by using a builder, either seeded with stack memory for
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This was referenced Dec 9, 2024
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danmoseley
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Dec 9, 2024
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src/libraries/System.Private.CoreLib/src/System/Collections/Generic/ValueListBuilder.cs:18
- The use of the null-forgiving operator (!) on scratchBuffer is unnecessary and potentially misleading. The constructor should ensure that scratchBuffer is non-null before assignment.
_span = scratchBuffer!;
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When the incoming enumerable isn't a
Task[]orList<Task>, we end up allocating either aTask[]or aList<T>(which then may incur one or more array allocations under the covers). We can avoid that by using an internal builder.Closes #110530