Skip to content

feat(ffe): backport dependent flag evaluation and RC capability to v46.1 - #2749

Closed
hhan2024 wants to merge 2 commits into
helen/ffe-dependent-flags-v46-basefrom
helen/ffe-dependent-flags-v46
Closed

hhan2024 wants to merge 2 commits into
helen/ffe-dependent-flags-v46-basefrom
helen/ffe-dependent-flags-v46

Conversation

@hhan2024

@hhan2024 hhan2024 commented Oct 28, 2026 •

Copy link
Copy Markdown
Contributor

What does this PR do?

Backport dependent-flag evaluation and prerequisite telemetry from #2748, plus the RC capability enum from #2745, onto the v46.1.0 source line consumed by Python. Dependency-free flags retain an allocation-only fast path. The evaluator also carries its shared experimentation-policy API and timestamp validation so recursive evaluations preserve the same context, logical time, and opt-out policy.

Motivation

Python cannot consume the current main-based native revision without a separate tracing-model migration. This compatibility revision preserves v46.1.0 crate versions, dependencies, and Rust 1.87 minimum while providing a reviewable immutable revision for the Python dependent-flag integration.

Additional notes

The base branch helen/ffe-dependent-flags-v46-base points exactly to v46.1.0 (bfa70eb6166db96673844c1a3fc1048f58e895d1); this is a compatibility backport for SDK consumption, not the mainline feature PR. #2748 remains the upstream implementation. This PR does not publish a release or automatically advertise SDK capability; Python must integrate the evaluation trace and enable its readiness reporter.

Validation

  • 129 FFE unit tests, 33 RC unit tests, and 12 documentation tests passed on Rust 1.87.0.
  • FFE tests include Python/exposure/EVP/evaluation-metrics features; RC tests verify bits 46+50 serialization.
  • Nightly formatting, stable clippy for FFE/RC/benchmark crates with warnings denied, and diff checks passed.
  • Evaluator source matches feat(ffe): evaluate dependent flags with prerequisite telemetry #2748, including depth-safe memoization, authored-order short-circuiting, prerequisite error propagation, and successful-path exposure eligibility.

Keep the Python SDK's native ABI while adding prerequisite evaluation traces, shared evaluation policy, and RC capability registration.

Environment: Datadog workspace

Co-Authored-By: Codex GPT-6 <noreply@localhost>
@github-actions

github-actions Bot commented Oct 28, 2026 •

Copy link
Copy Markdown
Contributor

📚 Documentation Check Results

⚠️ 1081 documentation warning(s) found

📦 libdd-ffe-test-suite - ✅ No warnings

📦 libdd-ffe - 391 warning(s)

📦 libdd-remote-config - 690 warning(s)


Updated: 2026-10-28 22:10:45 UTC | Commit: 50b1d64 | missing-docs job results

@github-actions

github-actions Bot commented Oct 28, 2026 •

Copy link
Copy Markdown
Contributor

🔒 Cargo Deny Results

⚠️ 18 issue(s) found, showing only errors (advisories, bans, sources)

📦 libdd-ffe-test-suite - 6 error(s)

Show output
error[unmaintained]: Bincode is unmaintained
   ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:24:1
   │
24 │ bincode 1.3.3 registry+https://github.com/rust-lang/crates.io-index
   │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ unmaintained advisory detected
   │
   ├ ID: RUSTSEC-2025-0141
   ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2025-0141
   ├ Due to a doxxing and harassment incident, the bincode team has taken the decision to cease development permanently.
     
     The team considers version 1.3.3 a complete version of bincode that is not in need of any updates.
     
     ## Alternatives to consider
     
     * [wincode](https://crates.io/crates/wincode)
     * [postcard](https://crates.io/crates/postcard)
     * [bitcode](https://crates.io/crates/bitcode)
     * [rkyv](https://crates.io/crates/rkyv)
   ├ Announcement: https://git.sr.ht/~stygianentity/bincode/tree/v3.0/item/README.md
   ├ Solution: No safe upgrade is available!
   ├ bincode v1.3.3
     └── (dev) libdd-ffe v2.0.0
         └── (dev) libdd-ffe-test-suite v46.1.0

error[vulnerability]: TLS 1.3 handshake messages incorrectly accepted across encryption level boundaries
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:194:1
    │
194 │ rustls 0.23.37 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ security vulnerability detected
    │
    ├ ID: RUSTSEC-2026-0285
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0285
    ├ Rustls accepted TLS 1.3 handshake messages sent at the wrong encryption level
      when they followed a key-changing message in the same record. For example,
      a plaintext `EncryptedExtensions` message packed into the same record as the
      `ServerHello` was accepted.
      
      RFC 8446 section 5.1 requires that handshake messages do not span key changes,
      and that implementations terminate the connection with an "unexpected_message"
      alert if they do.
      
      The handshake transcript is still authenticated, so a network-position attacker
      cannot use this to alter or complete a handshake; the practical effect is that
      a peer could send handshake messages that should be encrypted in plaintext
      without rustls rejecting the connection.
      
      This is functionally the same bug as Go's
      [GO-2026-4340](https://pkg.go.dev/vuln/GO-2026-4340) (CVE-2025-61730).
    ├ Announcement: https://github.com/rustls/rustls/pull/3265
    ├ Solution: Upgrade to >=0.23.45 (try `cargo update -p rustls`)
    ├ rustls v0.23.37
      ├── hyper-rustls v0.27.7
      │   └── libdd-common v8.0.0
      │       ├── libdd-capabilities-impl v7.0.0
      │       │   ├── (dev) libdd-ffe v2.0.0
      │       │   │   └── (dev) libdd-ffe-test-suite v46.1.0
      │       │   └── libdd-remote-config v7.0.0
      │       │       ├── libdd-ffe v2.0.0 (*)
      │       │       └── (dev) libdd-remote-config v7.0.0 (*)
      │       ├── libdd-ffe v2.0.0 (*)
      │       └── libdd-remote-config v7.0.0 (*)
      ├── libdd-common v8.0.0 (*)
      ├── rustls-platform-verifier v0.6.2
      │   └── libdd-common v8.0.0 (*)
      └── tokio-rustls v0.26.0
          └── hyper-rustls v0.27.7 (*)

error[vulnerability]: `Debug` impls for client session values expose TLS secrets
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:194:1
    │
194 │ rustls 0.23.37 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ security vulnerability detected
    │
    ├ ID: RUSTSEC-2026-0346
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0346
    ├ The `Debug` implementations of `Tls12ClientSessionValue` and
      `Tls13ClientSessionValue` were derived, and so included the TLS 1.2 master
      secret or TLS 1.3 resumption PSK in their output.
      
      Custom `ClientSessionStore` implementations that format these values with
      `Debug` (for example, when logging) could disclose these secrets to readers of
      the logs. This conflicts with rustls's
      [key-material redaction policy](https://github.com/rustls/rustls/blob/99f2358cae2954837dbb866faf6727de75489ab9/SECURITY.md#boundary-public-api).
      
      Ordinary connection and built-in session cache `Debug` output is redacted and
      is not affected.
    ├ Announcement: https://github.com/rustls/rustls/pull/3299
    ├ Solution: Upgrade to >=0.23.46 (try `cargo update -p rustls`)
    ├ rustls v0.23.37
      ├── hyper-rustls v0.27.7
      │   └── libdd-common v8.0.0
      │       ├── libdd-capabilities-impl v7.0.0
      │       │   ├── (dev) libdd-ffe v2.0.0
      │       │   │   └── (dev) libdd-ffe-test-suite v46.1.0
      │       │   └── libdd-remote-config v7.0.0
      │       │       ├── libdd-ffe v2.0.0 (*)
      │       │       └── (dev) libdd-remote-config v7.0.0 (*)
      │       ├── libdd-ffe v2.0.0 (*)
      │       └── libdd-remote-config v7.0.0 (*)
      ├── libdd-common v8.0.0 (*)
      ├── rustls-platform-verifier v0.6.2
      │   └── libdd-common v8.0.0 (*)
      └── tokio-rustls v0.26.0
          └── hyper-rustls v0.27.7 (*)

error[vulnerability]: Brotli certificate decompression can allocate up to 1 GiB before authentication
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:194:1
    │
194 │ rustls 0.23.37 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ security vulnerability detected
    │
    ├ ID: RUSTSEC-2026-0348
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0348
    ├ The built-in Brotli certificate decompressor (enabled by the non-default
      `brotli` crate feature) bounded the size of the decompressed output, but
      accepted a peer-selected history window. Brotli's large-window extension was
      enabled, so a five-byte header could cause an allocation of 1 GiB. A peer can
      abort a process whose allocator cannot satisfy that request.
      
      No trusted certificate is required by the attacker. Affected configurations are:
      
      - clients that enable the `brotli` feature and connect to a malicious server, and
      - servers that enable the `brotli` feature and request client certificates.
      
      Applications that do not enable the `brotli` feature are not affected.
    ├ Announcement: https://github.com/rustls/rustls/pull/3297
    ├ Solution: Upgrade to >=0.23.46 (try `cargo update -p rustls`)
    ├ rustls v0.23.37
      ├── hyper-rustls v0.27.7
      │   └── libdd-common v8.0.0
      │       ├── libdd-capabilities-impl v7.0.0
      │       │   ├── (dev) libdd-ffe v2.0.0
      │       │   │   └── (dev) libdd-ffe-test-suite v46.1.0
      │       │   └── libdd-remote-config v7.0.0
      │       │       ├── libdd-ffe v2.0.0 (*)
      │       │       └── (dev) libdd-remote-config v7.0.0 (*)
      │       ├── libdd-ffe v2.0.0 (*)
      │       └── libdd-remote-config v7.0.0 (*)
      ├── libdd-common v8.0.0 (*)
      ├── rustls-platform-verifier v0.6.2
      │   └── libdd-common v8.0.0 (*)
      └── tokio-rustls v0.26.0
          └── hyper-rustls v0.27.7 (*)

error[vulnerability]: Unauthenticated ServerHello can downgrade later connections to classical key exchange
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:194:1
    │
194 │ rustls 0.23.37 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ security vulnerability detected
    │
    ├ ID: RUSTSEC-2026-0349
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0349
    ├ The client recorded the server-selected key exchange group for each server
      name when processing the ServerHello, before the server was authenticated.
      This record is used to predict which key share to send in future ClientHellos
      to that server name.
      
      A network attacker can answer one connection attempt with a ServerHello
      selecting X25519, and then close the connection. Later ClientHellos for that
      name carry only an X25519 key share, while `supported_groups` still lists
      X25519MLKEM768 first. If the genuine server accepts that share rather than
      sending a HelloRetryRequest for its preferred hybrid group, the handshake
      completes with classical-only key exchange and no error. This persists for as
      long as the entry stays in the client's session store.
      
      The impact is loss of post-quantum confidentiality for affected connections
      ("harvest now, decrypt later"). There is no key compromise and no
      authentication bypass.
      
      The following are not affected:
      
      - connections to servers which send a HelloRetryRequest for their preferred group,
      - clients with resumption disabled (as nothing is stored), and
      - other server names.
      
      This behaviour is discussed in
      [draft-ietf-tls-key-share-prediction](https://www.ietf.org/archive/id/draft-ietf-tls-key-share-prediction-01.html#name-security-considerations),
      so the practical impact depends largely on server policy.
    ├ Announcement: https://github.com/rustls/rustls/pull/3355
    ├ Solution: Upgrade to >=0.23.46 (try `cargo update -p rustls`)
    ├ rustls v0.23.37
      ├── hyper-rustls v0.27.7
      │   └── libdd-common v8.0.0
      │       ├── libdd-capabilities-impl v7.0.0
      │       │   ├── (dev) libdd-ffe v2.0.0
      │       │   │   └── (dev) libdd-ffe-test-suite v46.1.0
      │       │   └── libdd-remote-config v7.0.0
      │       │       ├── libdd-ffe v2.0.0 (*)
      │       │       └── (dev) libdd-remote-config v7.0.0 (*)
      │       ├── libdd-ffe v2.0.0 (*)
      │       └── libdd-remote-config v7.0.0 (*)
      ├── libdd-common v8.0.0 (*)
      ├── rustls-platform-verifier v0.6.2
      │   └── libdd-common v8.0.0 (*)
      └── tokio-rustls v0.26.0
          └── hyper-rustls v0.27.7 (*)

error[unsound]: `AsyncFd::new` and related constructors violate I/O safety
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:246:1
    │
246 │ tokio 1.49.0 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ unsound advisory detected
    │
    ├ ID: RUSTSEC-2026-0386
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0386
    ├ `tokio::io::unix::AsyncFd` provides safe constructors (`new`, `with_interest`, `try_new`, and `try_with_interest`) that accept any `T: AsRawFd` rather than requiring proof of ownership or validity of the file descriptor. Because `RawFd` implements `AsRawFd`, safe code can construct an `AsyncFd` from an arbitrary or closed file descriptor, or close/replace the underlying file descriptor while the `AsyncFd` is still alive.
      
      This violates I/O safety in two ways:
      
      1. `AsyncFd<T>` implements `AsFd` for all `T: AsRawFd` by calling `BorrowedFd::borrow_raw(self.as_raw_fd())`, allowing safe code to obtain an arbitrary `BorrowedFd<'_>` without owning the file descriptor.
      2. Tokio's I/O driver stores a pointer to an internal allocation in the `epoll`/`kqueue` user data for registered file descriptors. If the underlying file descriptor is duplicated and then closed while an `AsyncFd` is alive, and the OS reuses that file descriptor number for a another IO resource on the same runtime, dropping the first `AsyncFd` deregisters the reused file descriptor number and frees the first while the original file description remains registered in `epoll`, leading to a use-after-free when a readiness event fires.
      
      Starting in Tokio 1.51.6, 1.53.3, and 1.54.0, `AsyncFd::new`, `AsyncFd::with_interest`, `AsyncFd::try_new`, and `AsyncFd::try_with_interest` are deprecated in favor of the `unsafe` constructors `AsyncFd::register` and `AsyncFd::register_with_interest`. Callers must ensure that the file descriptor remains valid, open, and unchanged for the lifetime of the `AsyncFd`.
    ├ Announcement: https://github.com/tokio-rs/tokio/pull/8587
    ├ Solution: Upgrade to >=1.51.6, <1.52.0 OR >=1.53.3 (try `cargo update -p tokio`)
    ├ tokio v1.49.0
      ├── h2 v0.4.19
      │   └── hyper v1.11.1
      │       ├── httpmock v0.8.0-alpha.1
      │       │   └── (dev) libdd-ffe v2.0.0
      │       │       └── (dev) libdd-ffe-test-suite v46.1.0
      │       ├── hyper-rustls v0.27.7
      │       │   └── libdd-common v8.0.0
      │       │       ├── libdd-capabilities-impl v7.0.0
      │       │       │   ├── (dev) libdd-ffe v2.0.0 (*)
      │       │       │   └── libdd-remote-config v7.0.0
      │       │       │       ├── libdd-ffe v2.0.0 (*)
      │       │       │       └── (dev) libdd-remote-config v7.0.0 (*)
      │       │       ├── libdd-ffe v2.0.0 (*)
      │       │       └── libdd-remote-config v7.0.0 (*)
      │       ├── hyper-util v0.1.17
      │       │   ├── httpmock v0.8.0-alpha.1 (*)
      │       │   ├── hyper-rustls v0.27.7 (*)
      │       │   ├── libdd-common v8.0.0 (*)
      │       │   └── libdd-remote-config v7.0.0 (*)
      │       ├── libdd-common v8.0.0 (*)
      │       └── libdd-remote-config v7.0.0 (*)
      ├── httpmock v0.8.0-alpha.1 (*)
      ├── hyper v1.11.1 (*)
      ├── hyper-rustls v0.27.7 (*)
      ├── hyper-util v0.1.17 (*)
      ├── (dev) libdd-capabilities-impl v7.0.0 (*)
      ├── libdd-common v8.0.0 (*)
      ├── libdd-ffe v2.0.0 (*)
      ├── libdd-remote-config v7.0.0 (*)
      ├── (dev) libdd-trace-protobuf v5.1.0
      │   └── libdd-remote-config v7.0.0 (*)
      ├── tokio-rustls v0.26.0
      │   └── hyper-rustls v0.27.7 (*)
      └── tokio-util v0.7.12
          ├── h2 v0.4.19 (*)
          └── libdd-remote-config v7.0.0 (*)

advisories FAILED, bans ok, sources ok

📦 libdd-ffe - 7 error(s)

Show output
error[unmaintained]: Bincode is unmaintained
   ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:22:1
   │
22 │ bincode 1.3.3 registry+https://github.com/rust-lang/crates.io-index
   │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ unmaintained advisory detected
   │
   ├ ID: RUSTSEC-2025-0141
   ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2025-0141
   ├ Due to a doxxing and harassment incident, the bincode team has taken the decision to cease development permanently.
     
     The team considers version 1.3.3 a complete version of bincode that is not in need of any updates.
     
     ## Alternatives to consider
     
     * [wincode](https://crates.io/crates/wincode)
     * [postcard](https://crates.io/crates/postcard)
     * [bitcode](https://crates.io/crates/bitcode)
     * [rkyv](https://crates.io/crates/rkyv)
   ├ Announcement: https://git.sr.ht/~stygianentity/bincode/tree/v3.0/item/README.md
   ├ Solution: No safe upgrade is available!
   ├ bincode v1.3.3
     └── (dev) libdd-ffe v2.0.0

error[unsound]: Potential use-after-free due to lack of panic safety in `LruCache::pop()`
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:128:1
    │
128 │ lru 0.16.4 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ unsound advisory detected
    │
    ├ ID: RUSTSEC-2026-0253
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0253
    ├ `LruCache::pop()` in `lru` was not panic-safe. If the `Drop` implementation of a stored key panics during `pop()`, `self.detach()` is never called, leaving dangling pointers in the internal doubly-linked list.
      
      A subsequent cache operation that triggers eviction can then dereference these dangling pointers:
      - The node is freed from the map, but remains linked in the LRU list due to the skipped `detach()` call
      - When a new insertion causes eviction, the LRU traversal encounters the dangling pointer
      - This results in a write to already-freed memory during the eviction process
      
      ## Impact
      
      - **CWE-416 (Use-After-Free):** memory corruption when subsequent cache operations access freed node pointers in the linked list
      - **CWE-415 (Double Free):** potential heap corruption when the same memory is freed multiple times
      
      Both types of undefined behavior can be invoked in safe Rust, but only if unwinding panics are enabled and `std::panic::catch_unwind` is used with key types that have potentially-panicking `Drop` implementations.
      
      ## Fix
      
      Fixed in `lru` 0.18.2 by detaching the node from the linked list before freeing it and dropping the key ([lru-rs#238](https://github.com/jeromefroe/lru-rs/pull/238)).
    ├ Announcement: https://github.com/jeromefroe/lru-rs/pull/238
    ├ Solution: Upgrade to >=0.18.2 (try `cargo update -p lru`)
    ├ lru v0.16.4
      └── libdd-ffe v2.0.0

error[vulnerability]: TLS 1.3 handshake messages incorrectly accepted across encryption level boundaries
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:170:1
    │
170 │ rustls 0.23.37 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ security vulnerability detected
    │
    ├ ID: RUSTSEC-2026-0285
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0285
    ├ Rustls accepted TLS 1.3 handshake messages sent at the wrong encryption level
      when they followed a key-changing message in the same record. For example,
      a plaintext `EncryptedExtensions` message packed into the same record as the
      `ServerHello` was accepted.
      
      RFC 8446 section 5.1 requires that handshake messages do not span key changes,
      and that implementations terminate the connection with an "unexpected_message"
      alert if they do.
      
      The handshake transcript is still authenticated, so a network-position attacker
      cannot use this to alter or complete a handshake; the practical effect is that
      a peer could send handshake messages that should be encrypted in plaintext
      without rustls rejecting the connection.
      
      This is functionally the same bug as Go's
      [GO-2026-4340](https://pkg.go.dev/vuln/GO-2026-4340) (CVE-2025-61730).
    ├ Announcement: https://github.com/rustls/rustls/pull/3265
    ├ Solution: Upgrade to >=0.23.45 (try `cargo update -p rustls`)
    ├ rustls v0.23.37
      ├── hyper-rustls v0.27.7
      │   └── libdd-common v8.0.0
      │       ├── libdd-capabilities-impl v7.0.0
      │       │   ├── (dev) libdd-ffe v2.0.0
      │       │   └── libdd-remote-config v7.0.0
      │       │       ├── libdd-ffe v2.0.0 (*)
      │       │       └── (dev) libdd-remote-config v7.0.0 (*)
      │       ├── libdd-ffe v2.0.0 (*)
      │       └── libdd-remote-config v7.0.0 (*)
      ├── libdd-common v8.0.0 (*)
      ├── rustls-platform-verifier v0.6.2
      │   └── libdd-common v8.0.0 (*)
      └── tokio-rustls v0.26.0
          └── hyper-rustls v0.27.7 (*)

error[vulnerability]: `Debug` impls for client session values expose TLS secrets
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:170:1
    │
170 │ rustls 0.23.37 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ security vulnerability detected
    │
    ├ ID: RUSTSEC-2026-0346
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0346
    ├ The `Debug` implementations of `Tls12ClientSessionValue` and
      `Tls13ClientSessionValue` were derived, and so included the TLS 1.2 master
      secret or TLS 1.3 resumption PSK in their output.
      
      Custom `ClientSessionStore` implementations that format these values with
      `Debug` (for example, when logging) could disclose these secrets to readers of
      the logs. This conflicts with rustls's
      [key-material redaction policy](https://github.com/rustls/rustls/blob/99f2358cae2954837dbb866faf6727de75489ab9/SECURITY.md#boundary-public-api).
      
      Ordinary connection and built-in session cache `Debug` output is redacted and
      is not affected.
    ├ Announcement: https://github.com/rustls/rustls/pull/3299
    ├ Solution: Upgrade to >=0.23.46 (try `cargo update -p rustls`)
    ├ rustls v0.23.37
      ├── hyper-rustls v0.27.7
      │   └── libdd-common v8.0.0
      │       ├── libdd-capabilities-impl v7.0.0
      │       │   ├── (dev) libdd-ffe v2.0.0
      │       │   └── libdd-remote-config v7.0.0
      │       │       ├── libdd-ffe v2.0.0 (*)
      │       │       └── (dev) libdd-remote-config v7.0.0 (*)
      │       ├── libdd-ffe v2.0.0 (*)
      │       └── libdd-remote-config v7.0.0 (*)
      ├── libdd-common v8.0.0 (*)
      ├── rustls-platform-verifier v0.6.2
      │   └── libdd-common v8.0.0 (*)
      └── tokio-rustls v0.26.0
          └── hyper-rustls v0.27.7 (*)

error[vulnerability]: Brotli certificate decompression can allocate up to 1 GiB before authentication
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:170:1
    │
170 │ rustls 0.23.37 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ security vulnerability detected
    │
    ├ ID: RUSTSEC-2026-0348
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0348
    ├ The built-in Brotli certificate decompressor (enabled by the non-default
      `brotli` crate feature) bounded the size of the decompressed output, but
      accepted a peer-selected history window. Brotli's large-window extension was
      enabled, so a five-byte header could cause an allocation of 1 GiB. A peer can
      abort a process whose allocator cannot satisfy that request.
      
      No trusted certificate is required by the attacker. Affected configurations are:
      
      - clients that enable the `brotli` feature and connect to a malicious server, and
      - servers that enable the `brotli` feature and request client certificates.
      
      Applications that do not enable the `brotli` feature are not affected.
    ├ Announcement: https://github.com/rustls/rustls/pull/3297
    ├ Solution: Upgrade to >=0.23.46 (try `cargo update -p rustls`)
    ├ rustls v0.23.37
      ├── hyper-rustls v0.27.7
      │   └── libdd-common v8.0.0
      │       ├── libdd-capabilities-impl v7.0.0
      │       │   ├── (dev) libdd-ffe v2.0.0
      │       │   └── libdd-remote-config v7.0.0
      │       │       ├── libdd-ffe v2.0.0 (*)
      │       │       └── (dev) libdd-remote-config v7.0.0 (*)
      │       ├── libdd-ffe v2.0.0 (*)
      │       └── libdd-remote-config v7.0.0 (*)
      ├── libdd-common v8.0.0 (*)
      ├── rustls-platform-verifier v0.6.2
      │   └── libdd-common v8.0.0 (*)
      └── tokio-rustls v0.26.0
          └── hyper-rustls v0.27.7 (*)

error[vulnerability]: Unauthenticated ServerHello can downgrade later connections to classical key exchange
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:170:1
    │
170 │ rustls 0.23.37 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ security vulnerability detected
    │
    ├ ID: RUSTSEC-2026-0349
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0349
    ├ The client recorded the server-selected key exchange group for each server
      name when processing the ServerHello, before the server was authenticated.
      This record is used to predict which key share to send in future ClientHellos
      to that server name.
      
      A network attacker can answer one connection attempt with a ServerHello
      selecting X25519, and then close the connection. Later ClientHellos for that
      name carry only an X25519 key share, while `supported_groups` still lists
      X25519MLKEM768 first. If the genuine server accepts that share rather than
      sending a HelloRetryRequest for its preferred hybrid group, the handshake
      completes with classical-only key exchange and no error. This persists for as
      long as the entry stays in the client's session store.
      
      The impact is loss of post-quantum confidentiality for affected connections
      ("harvest now, decrypt later"). There is no key compromise and no
      authentication bypass.
      
      The following are not affected:
      
      - connections to servers which send a HelloRetryRequest for their preferred group,
      - clients with resumption disabled (as nothing is stored), and
      - other server names.
      
      This behaviour is discussed in
      [draft-ietf-tls-key-share-prediction](https://www.ietf.org/archive/id/draft-ietf-tls-key-share-prediction-01.html#name-security-considerations),
      so the practical impact depends largely on server policy.
    ├ Announcement: https://github.com/rustls/rustls/pull/3355
    ├ Solution: Upgrade to >=0.23.46 (try `cargo update -p rustls`)
    ├ rustls v0.23.37
      ├── hyper-rustls v0.27.7
      │   └── libdd-common v8.0.0
      │       ├── libdd-capabilities-impl v7.0.0
      │       │   ├── (dev) libdd-ffe v2.0.0
      │       │   └── libdd-remote-config v7.0.0
      │       │       ├── libdd-ffe v2.0.0 (*)
      │       │       └── (dev) libdd-remote-config v7.0.0 (*)
      │       ├── libdd-ffe v2.0.0 (*)
      │       └── libdd-remote-config v7.0.0 (*)
      ├── libdd-common v8.0.0 (*)
      ├── rustls-platform-verifier v0.6.2
      │   └── libdd-common v8.0.0 (*)
      └── tokio-rustls v0.26.0
          └── hyper-rustls v0.27.7 (*)

error[unsound]: `AsyncFd::new` and related constructors violate I/O safety
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:220:1
    │
220 │ tokio 1.49.0 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ unsound advisory detected
    │
    ├ ID: RUSTSEC-2026-0386
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0386
    ├ `tokio::io::unix::AsyncFd` provides safe constructors (`new`, `with_interest`, `try_new`, and `try_with_interest`) that accept any `T: AsRawFd` rather than requiring proof of ownership or validity of the file descriptor. Because `RawFd` implements `AsRawFd`, safe code can construct an `AsyncFd` from an arbitrary or closed file descriptor, or close/replace the underlying file descriptor while the `AsyncFd` is still alive.
      
      This violates I/O safety in two ways:
      
      1. `AsyncFd<T>` implements `AsFd` for all `T: AsRawFd` by calling `BorrowedFd::borrow_raw(self.as_raw_fd())`, allowing safe code to obtain an arbitrary `BorrowedFd<'_>` without owning the file descriptor.
      2. Tokio's I/O driver stores a pointer to an internal allocation in the `epoll`/`kqueue` user data for registered file descriptors. If the underlying file descriptor is duplicated and then closed while an `AsyncFd` is alive, and the OS reuses that file descriptor number for a another IO resource on the same runtime, dropping the first `AsyncFd` deregisters the reused file descriptor number and frees the first while the original file description remains registered in `epoll`, leading to a use-after-free when a readiness event fires.
      
      Starting in Tokio 1.51.6, 1.53.3, and 1.54.0, `AsyncFd::new`, `AsyncFd::with_interest`, `AsyncFd::try_new`, and `AsyncFd::try_with_interest` are deprecated in favor of the `unsafe` constructors `AsyncFd::register` and `AsyncFd::register_with_interest`. Callers must ensure that the file descriptor remains valid, open, and unchanged for the lifetime of the `AsyncFd`.
    ├ Announcement: https://github.com/tokio-rs/tokio/pull/8587
    ├ Solution: Upgrade to >=1.51.6, <1.52.0 OR >=1.53.3 (try `cargo update -p tokio`)
    ├ tokio v1.49.0
      ├── h2 v0.4.19
      │   └── hyper v1.11.1
      │       ├── httpmock v0.8.0-alpha.1
      │       │   └── (dev) libdd-ffe v2.0.0
      │       ├── hyper-rustls v0.27.7
      │       │   └── libdd-common v8.0.0
      │       │       ├── libdd-capabilities-impl v7.0.0
      │       │       │   ├── (dev) libdd-ffe v2.0.0 (*)
      │       │       │   └── libdd-remote-config v7.0.0
      │       │       │       ├── libdd-ffe v2.0.0 (*)
      │       │       │       └── (dev) libdd-remote-config v7.0.0 (*)
      │       │       ├── libdd-ffe v2.0.0 (*)
      │       │       └── libdd-remote-config v7.0.0 (*)
      │       ├── hyper-util v0.1.17
      │       │   ├── httpmock v0.8.0-alpha.1 (*)
      │       │   ├── hyper-rustls v0.27.7 (*)
      │       │   ├── libdd-common v8.0.0 (*)
      │       │   └── libdd-remote-config v7.0.0 (*)
      │       ├── libdd-common v8.0.0 (*)
      │       └── libdd-remote-config v7.0.0 (*)
      ├── httpmock v0.8.0-alpha.1 (*)
      ├── hyper v1.11.1 (*)
      ├── hyper-rustls v0.27.7 (*)
      ├── hyper-util v0.1.17 (*)
      ├── (dev) libdd-capabilities-impl v7.0.0 (*)
      ├── libdd-common v8.0.0 (*)
      ├── libdd-ffe v2.0.0 (*)
      ├── libdd-remote-config v7.0.0 (*)
      ├── (dev) libdd-trace-protobuf v5.1.0
      │   ├── libdd-ffe v2.0.0 (*)
      │   └── libdd-remote-config v7.0.0 (*)
      ├── tokio-rustls v0.26.0
      │   └── hyper-rustls v0.27.7 (*)
      └── tokio-util v0.7.12
          ├── h2 v0.4.19 (*)
          └── libdd-remote-config v7.0.0 (*)

advisories FAILED, bans ok, sources ok

📦 libdd-remote-config - 5 error(s)

Show output
error[vulnerability]: TLS 1.3 handshake messages incorrectly accepted across encryption level boundaries
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:109:1
    │
109 │ rustls 0.23.37 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ security vulnerability detected
    │
    ├ ID: RUSTSEC-2026-0285
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0285
    ├ Rustls accepted TLS 1.3 handshake messages sent at the wrong encryption level
      when they followed a key-changing message in the same record. For example,
      a plaintext `EncryptedExtensions` message packed into the same record as the
      `ServerHello` was accepted.
      
      RFC 8446 section 5.1 requires that handshake messages do not span key changes,
      and that implementations terminate the connection with an "unexpected_message"
      alert if they do.
      
      The handshake transcript is still authenticated, so a network-position attacker
      cannot use this to alter or complete a handshake; the practical effect is that
      a peer could send handshake messages that should be encrypted in plaintext
      without rustls rejecting the connection.
      
      This is functionally the same bug as Go's
      [GO-2026-4340](https://pkg.go.dev/vuln/GO-2026-4340) (CVE-2025-61730).
    ├ Announcement: https://github.com/rustls/rustls/pull/3265
    ├ Solution: Upgrade to >=0.23.45 (try `cargo update -p rustls`)
    ├ rustls v0.23.37
      ├── hyper-rustls v0.27.7
      │   └── libdd-common v8.0.0
      │       ├── libdd-capabilities-impl v7.0.0
      │       │   └── libdd-remote-config v7.0.0
      │       │       └── (dev) libdd-remote-config v7.0.0 (*)
      │       └── libdd-remote-config v7.0.0 (*)
      ├── libdd-common v8.0.0 (*)
      ├── rustls-platform-verifier v0.6.2
      │   └── libdd-common v8.0.0 (*)
      └── tokio-rustls v0.26.0
          └── hyper-rustls v0.27.7 (*)

error[vulnerability]: `Debug` impls for client session values expose TLS secrets
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:109:1
    │
109 │ rustls 0.23.37 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ security vulnerability detected
    │
    ├ ID: RUSTSEC-2026-0346
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0346
    ├ The `Debug` implementations of `Tls12ClientSessionValue` and
      `Tls13ClientSessionValue` were derived, and so included the TLS 1.2 master
      secret or TLS 1.3 resumption PSK in their output.
      
      Custom `ClientSessionStore` implementations that format these values with
      `Debug` (for example, when logging) could disclose these secrets to readers of
      the logs. This conflicts with rustls's
      [key-material redaction policy](https://github.com/rustls/rustls/blob/99f2358cae2954837dbb866faf6727de75489ab9/SECURITY.md#boundary-public-api).
      
      Ordinary connection and built-in session cache `Debug` output is redacted and
      is not affected.
    ├ Announcement: https://github.com/rustls/rustls/pull/3299
    ├ Solution: Upgrade to >=0.23.46 (try `cargo update -p rustls`)
    ├ rustls v0.23.37
      ├── hyper-rustls v0.27.7
      │   └── libdd-common v8.0.0
      │       ├── libdd-capabilities-impl v7.0.0
      │       │   └── libdd-remote-config v7.0.0
      │       │       └── (dev) libdd-remote-config v7.0.0 (*)
      │       └── libdd-remote-config v7.0.0 (*)
      ├── libdd-common v8.0.0 (*)
      ├── rustls-platform-verifier v0.6.2
      │   └── libdd-common v8.0.0 (*)
      └── tokio-rustls v0.26.0
          └── hyper-rustls v0.27.7 (*)

error[vulnerability]: Brotli certificate decompression can allocate up to 1 GiB before authentication
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:109:1
    │
109 │ rustls 0.23.37 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ security vulnerability detected
    │
    ├ ID: RUSTSEC-2026-0348
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0348
    ├ The built-in Brotli certificate decompressor (enabled by the non-default
      `brotli` crate feature) bounded the size of the decompressed output, but
      accepted a peer-selected history window. Brotli's large-window extension was
      enabled, so a five-byte header could cause an allocation of 1 GiB. A peer can
      abort a process whose allocator cannot satisfy that request.
      
      No trusted certificate is required by the attacker. Affected configurations are:
      
      - clients that enable the `brotli` feature and connect to a malicious server, and
      - servers that enable the `brotli` feature and request client certificates.
      
      Applications that do not enable the `brotli` feature are not affected.
    ├ Announcement: https://github.com/rustls/rustls/pull/3297
    ├ Solution: Upgrade to >=0.23.46 (try `cargo update -p rustls`)
    ├ rustls v0.23.37
      ├── hyper-rustls v0.27.7
      │   └── libdd-common v8.0.0
      │       ├── libdd-capabilities-impl v7.0.0
      │       │   └── libdd-remote-config v7.0.0
      │       │       └── (dev) libdd-remote-config v7.0.0 (*)
      │       └── libdd-remote-config v7.0.0 (*)
      ├── libdd-common v8.0.0 (*)
      ├── rustls-platform-verifier v0.6.2
      │   └── libdd-common v8.0.0 (*)
      └── tokio-rustls v0.26.0
          └── hyper-rustls v0.27.7 (*)

error[vulnerability]: Unauthenticated ServerHello can downgrade later connections to classical key exchange
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:109:1
    │
109 │ rustls 0.23.37 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ security vulnerability detected
    │
    ├ ID: RUSTSEC-2026-0349
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0349
    ├ The client recorded the server-selected key exchange group for each server
      name when processing the ServerHello, before the server was authenticated.
      This record is used to predict which key share to send in future ClientHellos
      to that server name.
      
      A network attacker can answer one connection attempt with a ServerHello
      selecting X25519, and then close the connection. Later ClientHellos for that
      name carry only an X25519 key share, while `supported_groups` still lists
      X25519MLKEM768 first. If the genuine server accepts that share rather than
      sending a HelloRetryRequest for its preferred hybrid group, the handshake
      completes with classical-only key exchange and no error. This persists for as
      long as the entry stays in the client's session store.
      
      The impact is loss of post-quantum confidentiality for affected connections
      ("harvest now, decrypt later"). There is no key compromise and no
      authentication bypass.
      
      The following are not affected:
      
      - connections to servers which send a HelloRetryRequest for their preferred group,
      - clients with resumption disabled (as nothing is stored), and
      - other server names.
      
      This behaviour is discussed in
      [draft-ietf-tls-key-share-prediction](https://www.ietf.org/archive/id/draft-ietf-tls-key-share-prediction-01.html#name-security-considerations),
      so the practical impact depends largely on server policy.
    ├ Announcement: https://github.com/rustls/rustls/pull/3355
    ├ Solution: Upgrade to >=0.23.46 (try `cargo update -p rustls`)
    ├ rustls v0.23.37
      ├── hyper-rustls v0.27.7
      │   └── libdd-common v8.0.0
      │       ├── libdd-capabilities-impl v7.0.0
      │       │   └── libdd-remote-config v7.0.0
      │       │       └── (dev) libdd-remote-config v7.0.0 (*)
      │       └── libdd-remote-config v7.0.0 (*)
      ├── libdd-common v8.0.0 (*)
      ├── rustls-platform-verifier v0.6.2
      │   └── libdd-common v8.0.0 (*)
      └── tokio-rustls v0.26.0
          └── hyper-rustls v0.27.7 (*)

error[unsound]: `AsyncFd::new` and related constructors violate I/O safety
    ┌─ /home/runner/work/libdatadog/libdatadog/Cargo.lock:145:1
    │
145 │ tokio 1.49.0 registry+https://github.com/rust-lang/crates.io-index
    │ ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ unsound advisory detected
    │
    ├ ID: RUSTSEC-2026-0386
    ├ Advisory: https://rustsec.org/advisories/RUSTSEC-2026-0386
    ├ `tokio::io::unix::AsyncFd` provides safe constructors (`new`, `with_interest`, `try_new`, and `try_with_interest`) that accept any `T: AsRawFd` rather than requiring proof of ownership or validity of the file descriptor. Because `RawFd` implements `AsRawFd`, safe code can construct an `AsyncFd` from an arbitrary or closed file descriptor, or close/replace the underlying file descriptor while the `AsyncFd` is still alive.
      
      This violates I/O safety in two ways:
      
      1. `AsyncFd<T>` implements `AsFd` for all `T: AsRawFd` by calling `BorrowedFd::borrow_raw(self.as_raw_fd())`, allowing safe code to obtain an arbitrary `BorrowedFd<'_>` without owning the file descriptor.
      2. Tokio's I/O driver stores a pointer to an internal allocation in the `epoll`/`kqueue` user data for registered file descriptors. If the underlying file descriptor is duplicated and then closed while an `AsyncFd` is alive, and the OS reuses that file descriptor number for a another IO resource on the same runtime, dropping the first `AsyncFd` deregisters the reused file descriptor number and frees the first while the original file description remains registered in `epoll`, leading to a use-after-free when a readiness event fires.
      
      Starting in Tokio 1.51.6, 1.53.3, and 1.54.0, `AsyncFd::new`, `AsyncFd::with_interest`, `AsyncFd::try_new`, and `AsyncFd::try_with_interest` are deprecated in favor of the `unsafe` constructors `AsyncFd::register` and `AsyncFd::register_with_interest`. Callers must ensure that the file descriptor remains valid, open, and unchanged for the lifetime of the `AsyncFd`.
    ├ Announcement: https://github.com/tokio-rs/tokio/pull/8587
    ├ Solution: Upgrade to >=1.51.6, <1.52.0 OR >=1.53.3 (try `cargo update -p tokio`)
    ├ tokio v1.49.0
      ├── hyper v1.11.1
      │   ├── hyper-rustls v0.27.7
      │   │   └── libdd-common v8.0.0
      │   │       ├── libdd-capabilities-impl v7.0.0
      │   │       │   └── libdd-remote-config v7.0.0
      │   │       │       └── (dev) libdd-remote-config v7.0.0 (*)
      │   │       └── libdd-remote-config v7.0.0 (*)
      │   ├── hyper-util v0.1.17
      │   │   ├── hyper-rustls v0.27.7 (*)
      │   │   ├── libdd-common v8.0.0 (*)
      │   │   └── libdd-remote-config v7.0.0 (*)
      │   ├── libdd-common v8.0.0 (*)
      │   └── libdd-remote-config v7.0.0 (*)
      ├── hyper-rustls v0.27.7 (*)
      ├── hyper-util v0.1.17 (*)
      ├── (dev) libdd-capabilities-impl v7.0.0 (*)
      ├── libdd-common v8.0.0 (*)
      ├── libdd-remote-config v7.0.0 (*)
      ├── (dev) libdd-trace-protobuf v5.1.0
      │   └── libdd-remote-config v7.0.0 (*)
      ├── tokio-rustls v0.26.0
      │   └── hyper-rustls v0.27.7 (*)
      └── tokio-util v0.7.12
          └── libdd-remote-config v7.0.0 (*)

advisories FAILED, bans ok, sources ok

Updated: 2026-10-28 22:10:17 UTC | Commit: 50b1d64 | dependency-check job results

@datadog-datadog-prod-us1-2

datadog-datadog-prod-us1-2 Bot commented Oct 28, 2026 •

Copy link
Copy Markdown

Pipelines  Tests

🎉 All green!

🧪 All tests passed
❄️ No new flaky tests detected

🎯 Code Coverage (details)
• Patch Coverage: 97.85%
• Overall Coverage: 82.30%

This comment will be updated automatically if new data arrives.
🔗 Commit SHA: 9cb812d | Docs | View more details | Give us feedback!

Route flags without prerequisite conditions through the allocation-only evaluator, sharing validation and assignment construction with dependent evaluation.

Environment: Datadog workspace

Co-Authored-By: Codex GPT-6 <noreply@localhost>
@pr-commenter

pr-commenter Bot commented Oct 28, 2026 •

Copy link
Copy Markdown

Benchmarks

Comparison

Benchmark execution time: 2026-10-28 22:40:35

Comparing candidate commit 9cb812d in PR branch helen/ffe-dependent-flags-v46 with baseline commit bfa70eb in branch helen/ffe-dependent-flags-v46-base.

📊 Benchmarking dashboard

Found 0 performance improvements and 3 performance regressions! Performance is the same for 159 metrics, 0 unstable metrics.

Explanation

This is an A/B test comparing a candidate commit's performance against that of a baseline commit. Performance changes are noted in the tables below as:

  • 🟩 = significantly better candidate vs. baseline
  • 🟥 = significantly worse candidate vs. baseline

We compute a confidence interval (CI) over the relative difference of means between metrics from the candidate and baseline commits, considering the baseline as the reference.

If the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD), the change is considered significant.

Feel free to reach out to #apm-benchmarking-platform on Slack if you have any questions.

More details about the CI and significant changes

You can imagine this CI as a range of values that is likely to contain the true difference of means between the candidate and baseline commits.

CIs of the difference of means are often centered around 0%, because often changes are not that big:

---------------------------------(------|---^--------)-------------------------------->
                              -0.6%    0%  0.3%     +1.2%
                                 |          |        |
         lower bound of the CI --'          |        |
sample mean (center of the CI) -------------'        |
         upper bound of the CI ----------------------'

As described above, a change is considered significant if the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD).

For instance, for an execution time metric, this confidence interval indicates a significantly worse performance:

----------------------------------------|---------|---(---------^---------)---------->
                                       0%        1%  1.3%      2.2%      3.1%
                                                  |   |         |         |
       significant impact threshold --------------'   |         |         |
                      lower bound of CI --------------'         |         |
       sample mean (center of the CI) --------------------------'         |
                      upper bound of CI ----------------------------------'

scenario:vec_map/as_deduped_map/needs_dedup_1_in_4/8

  • 🟥 execution_time [+10.851ns; +10.991ns] or [+5.474%; +5.544%]

scenario:vec_map/contains_key/8

  • 🟥 execution_time [+4.403ns; +4.746ns] or [+5.595%; +6.031%]
  • 🟥 throughput [-5781943.478op/s; -5361973.873op/s] or [-5.687%; -5.274%]

Benchmark execution time: 2026-10-28 22:36:34

Comparing candidate commit 9cb812d in PR branch helen/ffe-dependent-flags-v46 with baseline commit bfa70eb in branch helen/ffe-dependent-flags-v46-base.

📊 Benchmarking dashboard

Found 2 performance improvements and 2 performance regressions! Performance is the same for 88 metrics, 0 unstable metrics.

Explanation

This is an A/B test comparing a candidate commit's performance against that of a baseline commit. Performance changes are noted in the tables below as:

  • 🟩 = significantly better candidate vs. baseline
  • 🟥 = significantly worse candidate vs. baseline

We compute a confidence interval (CI) over the relative difference of means between metrics from the candidate and baseline commits, considering the baseline as the reference.

If the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD), the change is considered significant.

Feel free to reach out to #apm-benchmarking-platform on Slack if you have any questions.

More details about the CI and significant changes

You can imagine this CI as a range of values that is likely to contain the true difference of means between the candidate and baseline commits.

CIs of the difference of means are often centered around 0%, because often changes are not that big:

---------------------------------(------|---^--------)-------------------------------->
                              -0.6%    0%  0.3%     +1.2%
                                 |          |        |
         lower bound of the CI --'          |        |
sample mean (center of the CI) -------------'        |
         upper bound of the CI ----------------------'

As described above, a change is considered significant if the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD).

For instance, for an execution time metric, this confidence interval indicates a significantly worse performance:

----------------------------------------|---------|---(---------^---------)---------->
                                       0%        1%  1.3%      2.2%      3.1%
                                                  |   |         |         |
       significant impact threshold --------------'   |         |         |
                      lower bound of CI --------------'         |         |
       sample mean (center of the CI) --------------------------'         |
                      upper bound of CI ----------------------------------'

scenario:ddsketch_read/ordered_bins/collapsing

  • 🟩 execution_time [-1.040µs; -1.031µs] or [-4.044%; -4.007%]

scenario:thread_cpu/alloc_free/system/4096

  • 🟥 execution_time [+11.399ns; +11.595ns] or [+14.124%; +14.367%]

scenario:thread_cpu/profiler_attached/fast_path_system/4096

  • 🟥 execution_time [+7.624ns; +7.774ns] or [+7.762%; +7.916%]

scenario:thread_cpu/profiler_attached/slow_path_system/4096

  • 🟩 execution_time [-7.430ns; -7.302ns] or [-4.767%; -4.685%]

Benchmark execution time: 2026-10-28 22:37:32

Comparing candidate commit 9cb812d in PR branch helen/ffe-dependent-flags-v46 with baseline commit bfa70eb in branch helen/ffe-dependent-flags-v46-base.

📊 Benchmarking dashboard

Found 6 performance improvements and 2 performance regressions! Performance is the same for 67 metrics, 24 unstable metrics.

Explanation

This is an A/B test comparing a candidate commit's performance against that of a baseline commit. Performance changes are noted in the tables below as:

  • 🟩 = significantly better candidate vs. baseline
  • 🟥 = significantly worse candidate vs. baseline

We compute a confidence interval (CI) over the relative difference of means between metrics from the candidate and baseline commits, considering the baseline as the reference.

If the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD), the change is considered significant.

Feel free to reach out to #apm-benchmarking-platform on Slack if you have any questions.

More details about the CI and significant changes

You can imagine this CI as a range of values that is likely to contain the true difference of means between the candidate and baseline commits.

CIs of the difference of means are often centered around 0%, because often changes are not that big:

---------------------------------(------|---^--------)-------------------------------->
                              -0.6%    0%  0.3%     +1.2%
                                 |          |        |
         lower bound of the CI --'          |        |
sample mean (center of the CI) -------------'        |
         upper bound of the CI ----------------------'

As described above, a change is considered significant if the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD).

For instance, for an execution time metric, this confidence interval indicates a significantly worse performance:

----------------------------------------|---------|---(---------^---------)---------->
                                       0%        1%  1.3%      2.2%      3.1%
                                                  |   |         |         |
       significant impact threshold --------------'   |         |         |
                      lower bound of CI --------------'         |         |
       sample mean (center of the CI) --------------------------'         |
                      upper bound of CI ----------------------------------'

scenario:datadog_sample_span/complex_rule_partial_match/wall_time

  • 🟩 execution_time [-11.700ns; -11.570ns] or [-5.256%; -5.198%]

scenario:glob_matcher/unicode_exact_match/wall_time

  • 🟩 execution_time [-3.734ns; -3.634ns] or [-4.735%; -4.608%]

scenario:sdk_test_data/rules-based

  • 🟥 execution_time [+37.476µs; +42.405µs] or [+14.217%; +16.087%]

scenario:single_flag_killswitch/rules-based

  • 🟥 execution_time [+47.238ns; +48.123ns] or [+29.691%; +30.247%]

scenario:trace_buffer/2_senders/no_delay

  • 🟩 execution_time [-189.533µs; -173.236µs] or [-9.153%; -8.366%]
  • 🟩 throughput [+80079.825op/s; +88202.737op/s] or [+9.211%; +10.145%]

scenario:trace_buffer/8_senders/no_delay

  • 🟩 execution_time [-336.385µs; -323.734µs] or [-5.648%; -5.436%]
  • 🟩 throughput [+69574.603op/s; +72299.589op/s] or [+5.755%; +5.980%]

Unstable benchmarks

These benchmarks have a confidence interval too wide to call a change; treat them as noise rather than signal.

scenario:datadog_sample_span/complex_rule_matching/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+555.735%; -555.735%]

scenario:datadog_sample_span/complex_rule_partial_match/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+560.190%; -557.837%]

scenario:datadog_sample_span/many_attributes_tag_rule/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+555.735%; -555.735%]

scenario:datadog_sample_span/multiple_rules_first_match/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+555.735%; -555.735%]

scenario:datadog_sample_span/multiple_rules_last_match/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+548.949%; -552.553%]

scenario:datadog_sample_span/name_pattern_rule_matching/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+555.735%; -555.735%]

scenario:datadog_sample_span/name_pattern_rule_not_matching/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+570.146%; -562.570%]

scenario:datadog_sample_span/parent_not_sampled_short_circuit/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+556.288%; -555.995%]

scenario:datadog_sample_span/parent_sampled_short_circuit/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+555.919%; -555.821%]

scenario:datadog_sample_span/resource_pattern_rule_matching/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+555.735%; -555.735%]

scenario:datadog_sample_span/resource_pattern_rule_not_matching/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+573.184%; -564.024%]

scenario:datadog_sample_span/root_span_no_rules/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+555.735%; -555.735%]

scenario:datadog_sample_span/service_rule_matching/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+552.366%; -554.152%]

scenario:datadog_sample_span/service_rule_not_matching/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+555.735%; -555.735%]

scenario:datadog_sample_span/tag_rule_matching/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+552.209%; -554.078%]

scenario:datadog_sample_span/tag_rule_not_matching/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+555.735%; -555.735%]

scenario:glob_matcher/ascii_case_insensitive_match/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+555.735%; -555.735%]

scenario:glob_matcher/ascii_exact_match/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+569.271%; -562.152%]

scenario:glob_matcher/ascii_exact_miss/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+545.187%; -550.799%]

scenario:glob_matcher/ascii_wildcard_backtrack_match/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+558.104%; -556.851%]

scenario:glob_matcher/ascii_wildcard_heavy_backtrack/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+552.305%; -554.123%]

scenario:glob_matcher/ascii_wildcard_question_match/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+555.735%; -555.735%]

scenario:glob_matcher/ascii_wildcard_star_match/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+558.079%; -556.840%]

scenario:glob_matcher/star_short_circuit/allocated_bytes

  • unstable execution_time [-0.000ns; +0.000ns] or [+557.308%; -556.476%]

Candidate

Omitted due to size.

Baseline

Omitted due to size.

@dd-octo-sts

dd-octo-sts Bot commented Oct 28, 2026 •

Copy link
Copy Markdown
Contributor

Artifact Size Benchmark Report

aarch64-alpine-linux-musl
Artifact Baseline Commit Change
/aarch64-alpine-linux-musl/lib/libdatadog_profiling.so 9.08 MB 9.21 MB +1.37% (+128.23 KB) ⚠️
/aarch64-alpine-linux-musl/lib/libdatadog_profiling.a 96.62 MB 96.21 MB --.42% (-422.42 KB) 💪
aarch64-unknown-linux-gnu
Artifact Baseline Commit Change
/aarch64-unknown-linux-gnu/lib/libdatadog_profiling.so 12.29 MB 12.38 MB +.76% (+96.18 KB) 🔍
/aarch64-unknown-linux-gnu/lib/libdatadog_profiling.a 107.97 MB 107.33 MB --.58% (-651.51 KB) 💪
libdatadog-x64-windows
Artifact Baseline Commit Change
/libdatadog-x64-windows/debug/dynamic/datadog_profiling_ffi.dll 29.19 MB 29.64 MB +1.53% (+458.50 KB) ⚠️
/libdatadog-x64-windows/debug/dynamic/datadog_profiling_ffi.lib 99.56 KB 99.02 KB --.54% (-556 B) 💪
/libdatadog-x64-windows/debug/dynamic/datadog_profiling_ffi.pdb 193.18 MB 195.26 MB +1.07% (+2.08 MB) ⚠️
/libdatadog-x64-windows/debug/static/datadog_profiling_ffi.lib 818.75 MB 823.38 MB +.56% (+4.63 MB) 🔍
/libdatadog-x64-windows/release/dynamic/datadog_profiling_ffi.dll 9.81 MB 9.72 MB --.88% (-89.00 KB) 💪
/libdatadog-x64-windows/release/dynamic/datadog_profiling_ffi.lib 99.56 KB 99.02 KB --.54% (-556 B) 💪
/libdatadog-x64-windows/release/dynamic/datadog_profiling_ffi.pdb 27.59 MB 27.73 MB +.48% (+136.00 KB) 🔍
/libdatadog-x64-windows/release/static/datadog_profiling_ffi.lib 55.87 MB 55.81 MB --.11% (-63.76 KB) 💪
libdatadog-x86-windows
Artifact Baseline Commit Change
/libdatadog-x86-windows/debug/dynamic/datadog_profiling_ffi.dll 25.61 MB 26.13 MB +2.01% (+529.50 KB) ⚠️
/libdatadog-x86-windows/debug/dynamic/datadog_profiling_ffi.lib 101.12 KB 100.56 KB --.55% (-572 B) 💪
/libdatadog-x86-windows/debug/dynamic/datadog_profiling_ffi.pdb 198.87 MB 200.78 MB +.95% (+1.90 MB) 🔍
/libdatadog-x86-windows/debug/static/datadog_profiling_ffi.lib 806.98 MB 808.67 MB +.20% (+1.68 MB) 🔍
/libdatadog-x86-windows/release/dynamic/datadog_profiling_ffi.dll 7.60 MB 7.51 MB --1.22% (-95.50 KB) 💪
/libdatadog-x86-windows/release/dynamic/datadog_profiling_ffi.lib 101.12 KB 100.56 KB --.55% (-572 B) 💪
/libdatadog-x86-windows/release/dynamic/datadog_profiling_ffi.pdb 29.73 MB 29.80 MB +.21% (+64.00 KB) 🔍
/libdatadog-x86-windows/release/static/datadog_profiling_ffi.lib 52.81 MB 52.67 MB --.25% (-138.04 KB) 💪
x86_64-alpine-linux-musl
Artifact Baseline Commit Change
/x86_64-alpine-linux-musl/lib/libdatadog_profiling.a 86.54 MB 86.75 MB +.24% (+220.00 KB) 🔍
/x86_64-alpine-linux-musl/lib/libdatadog_profiling.so 10.12 MB 10.02 MB --1.00% (-103.74 KB) 💪
x86_64-unknown-linux-gnu
Artifact Baseline Commit Change
/x86_64-unknown-linux-gnu/lib/libdatadog_profiling.a 102.44 MB 102.30 MB --.13% (-137.86 KB) 💪
/x86_64-unknown-linux-gnu/lib/libdatadog_profiling.so 12.37 MB 12.25 MB --.96% (-121.67 KB) 💪

@chatgpt-codex-connector

chatgpt-codex-connector Bot commented Nov 3, 2026 •

Copy link
Copy Markdown

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review Status Commit Review trigger
📝 Code Review ✅ Completed 2026-11-03T17:02:32.513236Z 9cb812d Draft marked ready
🔒 Security Review ✅ Completed 2026-11-03T17:07:03.217540Z 9cb812d Draft marked ready
ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

  • Open a pull request for review
  • Mark a draft as ready
  • Comment "@codex review" or "@codex security review".

Codex reacts with 👀 while any review is running, comments if it has suggestions, and reacts with 👍 once all reviews finish with no findings.

hhan2024 commented Nov 3, 2026

Copy link
Copy Markdown
Contributor Author

Closing in favor of the mainline release-and-upgrade path, consistent with the repository backport policy for new features. #2748 remains the evaluator implementation. Python DataDog/dd-trace-py#21346 and Ruby DataDog/dd-trace-rb#6613 are being updated to remove their v46 backport dependencies.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

None yet

Projects

None yet

Development

Successfully merging this pull request may close these issues.

1 participant