From f29327ff6093bc09c445028bd05a172e570e8486 Mon Sep 17 00:00:00 2001 From: gonzalobg <65027571+gonzalobg@users.noreply.github.com> Date: Wed, 27 Aug 2025 16:21:07 +0200 Subject: [PATCH] Clarify that align_offset overaligns The current documentation is not clear whether adding `a` to a pointer overaligns (align up) or underaligns (align down). It should say this explicitly. --- library/core/src/ptr/mod.rs | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/library/core/src/ptr/mod.rs b/library/core/src/ptr/mod.rs index 6fc85a83e179e..6b94088cb5679 100644 --- a/library/core/src/ptr/mod.rs +++ b/library/core/src/ptr/mod.rs @@ -2166,10 +2166,9 @@ pub unsafe fn write_volatile(dst: *mut T, src: T) { } } -/// Align pointer `p`. +/// Calculate an element-offset that increases a pointer's alignment. /// -/// Calculate offset (in terms of elements of `size_of::()` stride) that has to be applied -/// to pointer `p` so that pointer `p` would get aligned to `a`. +/// Calculate an element-offset (not byte-offset) that when added to a given pointer `p`, increases `p`'s alignment to at least the given alignment `a`. /// /// # Safety /// `a` must be a power of two.