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Attempt to clarify the deallocation rules for UMBP. #85101

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Oct 24, 2025
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Attempt to clarify the deallocation rules for UMBP. #85101

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Attempt to clarify the deallocation rules for UMBP.
stephentyrone Oct 24, 2025
a788c13
Update stdlib/public/core/UnsafePointer.swift
stephentyrone Oct 24, 2025
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4 changes: 4 additions & 0 deletions stdlib/public/core/UnsafePointer.swift
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Expand Up @@ -788,6 +788,10 @@ extension UnsafeMutablePointer where Pointee: ~Copyable {
///
/// intPointer.deallocate()
///
/// You must only use `deallocate()` to end the lifetime of memory
/// created with `allocate()`; it is a programming error to use `free` or
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@glessard glessard Oct 24, 2025 •
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Should we call out free() explicitly, or should we say "other deallocation functions", or maybe "deallocation functions from other libraries"

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Yeah, I was torn on this. But I feel like free is the primary means of abuse, and anyone who was going to use anything else that they shouldn't will understand that the rules for free apply to them as well.

/// another deallocation API, and may result in undefined behavior.
///
/// - Parameter count: The amount of memory to allocate, counted in instances
/// of `Pointee`.
@inlinable
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