Fix memory leak in alloc_try_with and try_alloc_try_with - #322
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…k rewind When `alloc_try_with` / `try_alloc_try_with` allocates a new chunk for the `Result<T, E>` and the closure returns `Err`, the rewind logic sets the bump pointer to `footer.data` (the LOWEST address of the chunk). Since the bump pointer grows downward, this marks the chunk as completely full instead of empty, leaking the entire chunk until the bump is reset. Co-Authored-By: Claude <noreply@anthropic.com>
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Ah, it seems I've reinvented #315 |
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When allocating a new chunk, these functions erroneously mark it as full. The pointers are set to the start of the chunk, but the bump allocator grows downwards, so the space in the newly allocated chunk appears to be exhausted.
This doc comment might have been the source of the error, since it's not entirely clear what "start" and "end" means for an allocator growing downwards in the address space:
bumpalo/src/lib.rs
Lines 301 to 304 in 657caf8
The issue was identified by Claude Opus 4.7 as part of a memory safety audit. It turned up no security issues as of commit 657caf8.