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ECO003-send-sync-violations-on-pub-types

Dimension: ecosystem Default severity: Low Languages: Rust (file-level) CWE: (none)

What it detects​

Fires when a pub struct contains a raw pointer field (*mut T or *const T) without an unsafe impl Send declaration in the same file.

Raw pointers are not Send by default. A public struct containing a raw pointer that is neither Send nor documented as non-Send is a usability hazard: downstream consumers cannot share it across threads without unsafe code.

Heuristic limitations​

  • File-wide suppression: if any unsafe impl Send appears anywhere in the file, the rule is suppressed for the entire file. This may miss structs in the same file that lack Send implementations.
  • Sync is not checked — only Send.
  • Wrapping types (e.g. NonNull<T>, AtomicPtr<T>) that are safe to send are not recognized; they appear as raw pointer wrappers.

Always review findings manually.

Example — flagged​

pub struct Buffer {
    ptr: *mut u8,
    len: usize,
}
// No unsafe impl Send — downstream users cannot share Buffer across threads

Example — not flagged​

pub struct Buffer {
    ptr: *mut u8,
    len: usize,
}

// SAFETY: Buffer owns the pointer and provides exclusive access via &mut self
unsafe impl Send for Buffer {}

Fix guidance​

Add unsafe impl Send for YourStruct {} with a // SAFETY: comment explaining the invariants, or change the raw pointer to a wrapper type that is Send by default (e.g. NonNull<T> is !Send, but AtomicPtr<T> is Send).

Suppression​

// zuit: ignore ECO003-send-sync-violations-on-pub-types
pub struct Buffer { ptr: *mut u8, len: usize }

References​