LinkedList::remove forgets the allocator #125950
Description
I tried this code:
#![feature(allocator_api)] #![feature(linked_list_remove)] use std::{ alloc::{AllocError, Allocator, Layout}, collections::LinkedList, process::abort, ptr::NonNull, }; struct M; unsafe impl Allocator for M { fn allocate(&self, layout: std::alloc::Layout) -> Result<NonNull<[u8]>, AllocError> { unsafe { if layout.align() > std::mem::align_of::<usize>() { abort(); } let ptr = libc::malloc(layout.size()) as *mut u8; if ptr.is_null() { abort(); } println!("alloc: {:?}", ptr); let nonnull = NonNull::new_unchecked(ptr); Ok(NonNull::slice_from_raw_parts(nonnull, layout.size())) } } unsafe fn deallocate(&self, ptr: NonNull<u8>, _layout: Layout) { unsafe { println!("dealloc: {:?}", ptr); libc::free(ptr.as_ptr() as _); } } } fn main() { let alloc = &M; let mut list = LinkedList::new_in(alloc); list.push_back(5); list.remove(0); }I expected to see this happen: alloc and dealloc is printed
Instead, this happened: only alloc is printed
Meta
rustc --version --verbose:
rustc 1.80.0-nightly (f67a1acc0 2024-06-01) binary: rustc commit-hash: f67a1acc04c7ecbf05751b17592dd8d245b75256 commit-date: 2024-06-01 host: x86_64-unknown-linux-gnu release: 1.80.0-nightly LLVM version: 18.1.6 LinkedList::remove forgets that it's been initialized with an allocator, and always deletes the node with the global allocator.
rust/library/alloc/src/collections/linked_list.rs
Line 1708 in 1689a5a
There seems to be one more place where this happens in the same file.