# C++ private SDK regression fixtures — 2026-10-04

The public harness retained two tests that require private C++ SDK headers:
the TCPDirect single-accept deadline regression and the mmap-store durable
session matrix. They now live at their matching `internal/bench/` paths.
The actual benchmark runner remains in the harness, with its explicit SDK
input. Development conformance, local preflight and durability readiness
continue to refer to the original durable-session test.

Source pin: `b2708eb6fdd9926dfe6fc58f848d0345bb87e9f1`. The complete public
archive contains 750 files including the three templates. The two private
fixtures preserve all nine original function ASTs and 27 assertion calls;
the only fixture byte edits change their enclosing root from `parents[4]`
to `parents[5]`. Three private tool entries change only the relocated path.
SDK, benchmark runner, workload, timing and adapter code are unchanged.

## Original controls and failures

The local wrapper was first called with a shortened capsule path and refused
before materialization or any test. Its exact reproduced refusal and bad
argument remain in [the invocation evidence](evidence/cpp-private-fixtures-20261004/original/original-local-invocation/receipt.json).
The corrected invocation uses the producer's actual path; no check changed.

HP inspected its slot, processes and memory, then obtained a high-priority
shared lease. The relocated TCPDirect suite passed both original tests without
skips. The original durability compile then failed because the qualification
snapshot included 192 SDK headers but omitted their tuning-kernel includes.
The [original compiler failure](evidence/cpp-private-fixtures-20261004/original/hp-qualification/durability-private-matrix.stderr)
and [outer result](evidence/cpp-private-fixtures-20261004/original/hp-qualification/result.json)
remain unchanged. This was an incomplete supplied SDK input, not a passing
build or a test assertion removed by migration.

## Corrected qualification

The corrected snapshot adds the fourteen required kernel files from the same
frozen SDK pin `28f276e2ed6c58b7e99478ebf34b563ce09a9dfc`: 206 declared C++
compile inputs in total. All original 192 header bytes/modes and both fixture
bytes remain identical. This is an explicitly selected SDK input snapshot,
not a fresh whole-engine build or current SDK release qualification.

Under another HP shared/high lease, the unchanged original durable test
compiles with GCC 11.5 and its original `-O2 -std=c++17 -Wall -Wextra` flags.
It passes all eight workload/durability/measurement-point arms, ten measured
samples per arm, the raw/manifest checks, and the overwrite and invalid-option
refusals. Its original temporary raw/manifests and executable are checked by
the test and removed at exit. One fresh test passes with zero skips. The two
passing original TCPDirect tests are explicitly reused from their unchanged
inputs; they are not relabelled as fresh corrected-generation executions.
See [the corrected receipt](evidence/cpp-private-fixtures-20261004/corrected/hp-qualification/result.json).

Local text/routing verification passes the twelve original preflight tests,
eleven original readiness mutation tests and the one relevant original
conformance-stage test, all without skips. Both actual stage factories resolve
the private fixture, include it in prerequisites, and find its file. No local
C++ compile or heavy suite is added beside other sessions' builds. See
[the routing receipt](evidence/cpp-private-fixtures-20261004/original/local-routing/result.json).

The full harness, private fixture/tool inputs and SDK input bytes/modes remain
unchanged. The passing materializations and test temp fixtures are removed.
All original failed source snapshots and command streams remain sealed with
the corrected result; both owning local/HP capsules and the failed HP source materialization are
removed after their exact archived bytes/modes were verified. Both benchmark
hosts verify all 51 sealed archive files and the seal itself.

These are functional private-fixture and source-boundary checks. They supply
no quiet latency, physical, report-grade, full SDK or coordinated release gate.
Current readiness has 747 selected source files plus three templates, zero
scrub/private/unresolved-reference/dead-link findings and 67 textual escapes.

## Retention

`~/archive/libhft/cpp-private-fixtures-20261004` retains the original failure
and corrected whole-harness capsules, private inputs, SDK headers/kernels,
producer/checker sources and command receipts. The
[archive receipt](evidence/cpp-private-fixtures-20261004/private-archive.json)
identifies its seal. SDK and complete source tarballs remain only in the private
archive; committed receipts and streams can enter the website evidence archive.