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+# Linear Static 3D Euler Beam Build/Test Report
+
+## Metadata
+
+- feature_id: `linear-static-3d-euler-beam`
+- source_commit: `400db191ce9f766ca6b34e5b609eaa13c54ccfa3`
+- source_implementation_report: `docs/implementation-plans/linear-static-3d-euler-beam-implementation-report.md`
+- source_implementation_plan: `docs/implementation-plans/linear-static-3d-euler-beam.md`
+- status: `pass-for-reference-verification`
+- owner_agent: `build-test-executor-agent`
+- date: `2026-08-09`
+- evidence_window: `2026-08-09T23:16:20.8670416+09:00` through `2026-08-09T23:20:15.7264584+09:00`
+
+## Verdict
+
+Fresh Visual Studio 18 2026/MSVC x64 Debug configuration, a clean full rebuild,
+the exact Step 25 configure/build commands, nonzero JSON discovery, the feature-label
+CTest run, and the full CTest run all passed. CTest discovered the expected 83 tests
+and both executed suites passed 83/83. The clean rebuild emitted no compiler or linker
+warning line, and generated FESA product projects retain Level 4 plus warnings-as-errors.
+
+The build/test gate therefore passes for handoff to Step 26 Reference Verification.
+This verdict does not approve reference tolerance, physics sanity, or release readiness.
+
+## Execution Environment
+
+- os: `Microsoft Windows 11 Home 10.0.26200 build 26200; 64-bit`
+- source_head: `400db191ce9f766ca6b34e5b609eaa13c54ccfa3`
+- generator: `Visual Studio 18 2026`
+- Visual Studio: `Community 18.8.2` (`18.8.12023.21`)
+- MSBuild: `18.8.2+ce25c0108`
+- compiler: `MSVC 19.51.36252.0`
+- compiler_architecture: `x64`
+- Windows SDK: `10.0.26100.0`
+- language: `C++17`, required, extensions disabled
+- config: `Debug`
+- build_dir: `.harness/build`
+- harness_config: absent; repository auto-CMake defaults plus Step 25 explicit cache values
+- project_selection: auto CMake from root `CMakeLists.txt`
+- command_discovery_path: default CMake/MSVC x64 Debug with explicit local dependency paths
+- CMake / CTest: `4.4.0 / 4.4.0`
+
+### Dependency Revisions
+
+| dependency | resolved revision or version | evidence |
+| --- | --- | --- |
+| GoogleTest | `04ee1b4f2aefdffb0135d7cf2a2c519fe50dabe4` | clean `C:/git/googletest` checkout HEAD |
+| Intel oneMKL | `2026.1.0` | `MKLConfigVersion.cmake`; configure reported `MKL_VERSION: 2026.1.0`, dynamic ILP64, Intel threading |
+| Intel oneTBB | `2023.1.0` | `TBBConfigVersion.cmake` from the configured `2023.1` package |
+| HDF5 | `2.1.1` | `hdf5-config-version.cmake` from the configured `2.1.1` package |
+
+## Freshness and Configuration Resolution
+
+The ignored generated build tree already existed. Fresh evidence was obtained without
+reusing its cache or products by running CMake `--fresh` with the generator explicitly
+fixed to Visual Studio 18 2026, then running the generated `clean` target before the
+full build. The literal no-`--fresh`, no-`-G` configure command from Step 25 was then
+run against that resolved VS18 cache and followed by the literal build, discovery,
+feature-label, and full-test commands.
+
+Post-configure metadata recorded:
+
+- `CMAKE_GENERATOR=Visual Studio 18 2026`
+- `CMAKE_GENERATOR_PLATFORM=x64`
+- `CMAKE_CXX_COMPILER_ID=MSVC`
+- `CMAKE_CXX_COMPILER_VERSION=19.51.36252.0`
+- `CMAKE_CXX_COMPILER_ARCHITECTURE_ID=x64`
+
+## Command Log Summary
+
+| order | command | start / end | exit code | duration | verdict and stdout/stderr tail |
+| ---: | --- | --- | ---: | ---: | --- |
+| 1 | `cmake --fresh -S . -B .harness/build -G "Visual Studio 18 2026" -A x64 -DFESA_GTEST_SOURCE_DIR=C:/git/googletest "-DMKL_DIR=C:/Program Files (x86)/Intel/oneAPI/mkl/2026.1/lib/cmake/mkl" "-DTBB_DIR=C:/Program Files (x86)/Intel/oneAPI/tbb/2023.1/lib/cmake/tbb" "-DHDF5_DIR=C:/Program Files/HDF_Group/HDF5/2.1.1/cmake"` | `23:16:20.867+09:00` / `23:16:27.706+09:00` | 0 | `6.836 s` | pass; MKL 2026.1.0 and required runtime libraries resolved; `Configuring done`, `Generating done`, build files written to `.harness/build` |
+| 2 | `cmake --build .harness/build --config Debug --target clean` | `23:16:37.194+09:00` / `23:16:37.914+09:00` | 0 | `0.716 s` | pass; generated VS18 clean target completed |
+| 3 | `cmake --build .harness/build --config Debug` | `23:16:47.054+09:00` / `23:18:01.769+09:00` | 0 | `74.713 s` | pass; clean compile/link produced `fesa.exe` and all three test executables; warning scan count `0` |
+| 4 | `cmake -S . -B .harness/build -A x64 -DFESA_GTEST_SOURCE_DIR=C:/git/googletest "-DMKL_DIR=C:/Program Files (x86)/Intel/oneAPI/mkl/2026.1/lib/cmake/mkl" "-DTBB_DIR=C:/Program Files (x86)/Intel/oneAPI/tbb/2023.1/lib/cmake/tbb" "-DHDF5_DIR=C:/Program Files/HDF_Group/HDF5/2.1.1/cmake"` | `23:19:10.210+09:00` / `23:19:10.861+09:00` | 0 | `0.649 s` | pass; exact Step 25 command selected Windows SDK 10.0.26100.0, retained VS18/x64, and completed configure/generate |
+| 5 | `cmake --build .harness/build --config Debug` | `23:19:25.404+09:00` / `23:19:28.969+09:00` | 0 | `3.562 s` | pass; exact Step 25 build confirmed `fesa_solver`, `fesa.exe`, and all test executables; warning scan count `0` |
+| 6 | `ctest --test-dir .harness/build -C Debug --show-only=json-v1` | `23:19:45.728+09:00` / `23:19:45.798+09:00` | 0 | `0.065 s` | pass; JSON kind `ctestInfo` version 1.0; 83 tests; every test has the feature label |
+| 7 | `ctest --test-dir .harness/build -C Debug -L linear-static-3d-euler-beam --output-on-failure` | `23:20:00.199+09:00` / `23:20:04.163+09:00` | 0 | `3.961 s` | pass; `100% tests passed out of 83`; real test time `3.92 s` |
+| 8 | `ctest --test-dir .harness/build -C Debug --output-on-failure` | `23:20:11.899+09:00` / `23:20:15.726+09:00` | 0 | `3.825 s` | pass; `100% tests passed out of 83`; real test time `3.79 s` |
+
+An initial post-clean discovery/feature/full smoke was also run before the literal
+configure replay: discovery exit 0 in `0.068 s` with 83 tests, feature-label CTest
+exit 0 in `4.244 s` with 83/83, and full CTest exit 0 in `4.011 s` with 83/83.
+Rows 4 through 8 are the final canonical Step 25 acceptance chain.
+
+## Validation Results
+
+| validation_stage | result | evidence |
+| --- | --- | --- |
+| harness self-test | skipped | No Harness Python, Hook, or agent-config file is part of HEAD `400db19` verification scope. |
+| fresh configure | pass | Explicit VS18/x64 `--fresh` configure exit 0, followed by clean target exit 0. |
+| exact configure | pass | Literal Step 25 configure exit 0; generated metadata is MSVC/x64. |
+| clean full build | pass | Exit 0 after clean; all source and test translation units compiled and linked. |
+| exact build | pass | Exit 0; product and three test executables confirmed. |
+| compiler/warning policy | pass | `fesa_solver` and `fesa_cli` generated projects have `Level4` and `TreatWarningAsError=true`; clean and exact build scans found zero warning lines. |
+| CTest discovery | pass | Exit 0; 83 tests, greater than zero and equal to the expected inventory. |
+| feature-specific tests | pass | Label `linear-static-3d-euler-beam`: 83/83 passed. |
+| full CTest | pass | 83/83 passed with zero failed tests. |
+| reference immutability | pass | Pre/post `git diff --exit-code -- reference/` exit 0, status empty, and four exact SHA-256 values unchanged. |
+| source worktree before report | pass | `git status --short` empty at HEAD `400db19`. |
+
+## CTest Inventory
+
+### Label Inventory
+
+| label | count |
+| --- | ---: |
+| `linear-static-3d-euler-beam` | 83 |
+| `unit` | 73 |
+| `integration` | 5 |
+| `reference` | 5 |
+
+### Suite Inventory and Step Trace
+
+| implementation Step | CTest suite or suites | count | cumulative count | Step 7-24 report evidence audit |
+| ---: | --- | ---: | ---: | --- |
+| 7 | `BuildInfo` | 2 | 2 | pass |
+| 8 | `CoreDiagnostics` | 3 | 5 | pass |
+| 9 | `DenseMath` | 2 | 7 | pass |
+| 10 | `DomainModel` | 3 | 10 | pass |
+| 11 | `InpSyntax` | 4 | 14 | pass |
+| 12 | `InpDomainMapping` | 5 | 19 | pass |
+| 13 | `AnalysisModel` | 3 | 22 | pass |
+| 14 | `DofManager` | 4 | 26 | pass |
+| 15 | `AnalysisState` | 3 | 29 | pass |
+| 16 | `EulerBeam3D` | 10 | 39 | pass |
+| 17 | `ParallelFor` | 3 | 42 | pass |
+| 18 | `SparseAssembly` | 5 | 47 | pass |
+| 19 | `EssentialConstraints` | 4 | 51 | pass |
+| 20 | `MklPardisoSolver` | 6 | 57 | pass |
+| 21 | `LoadAssembly` | 5 | 62 | pass |
+| 22 | `ResultRecovery` | 6 | 68 | pass |
+| 23 | `Hdf5ResultsWriter` | 5 | 73 | pass |
+| 24 | `LinearStaticCli` (5), `ReferenceComparisonContract` (4), `B33ReferenceComparison` (1) | 10 | 83 | pass |
+
+The JSON inventory contains every exact test name registered by GoogleTest discovery.
+No duplicate CTest name was observed; the label partition is exactly 73 unit + 5
+integration + 5 reference = 83.
+
+## Step 7-24 Implementation Evidence Audit
+
+The cumulative implementation report was checked block-by-block against the implementation
+plan and the phase index summaries. All 18 Step blocks are present and each records:
+
+- its matching `TASK-07` through `TASK-24`, `status: completed`, changed files,
+  requirement IDs, and test IDs;
+- at least one implementation-owned nonzero RED command with the expected missing API
+  or named behavioral failure;
+- a zero-exit GREEN build/test for the Step's targeted CTest suite;
+- zero-exit MSVC x64 configure/build, nonzero JSON discovery, and zero-failure full CTest;
+- `/W4 /WX` or equivalent generated warning-policy evidence and reference-tree
+  immutability evidence.
+
+Step 20 and Step 22 additionally retain valid behavioral RED/GREEN correction evidence.
+Step 23 records its environment link incident separately from the valid missing-API RED,
+so the environment incident was not counted as TDD evidence. The cumulative counts in the
+implementation report and the Step 7-24 phase summaries progress exactly to the freshly
+discovered 83-test inventory above.
+
+The implementation report's cumulative header still says `in-progress`; the audited
+step-local evidence contract and phase index nevertheless mark every implementation Step
+7-24 `completed`. This stale aggregate header is not a missing Step block, missing test,
+or failed build/test gate and was not modified by the independent executor.
+
+## `/W4 /WX` and Warning Audit
+
+- `src/fesa/CMakeLists.txt` applies `/W4 /WX` privately to `fesa_solver` and `fesa_cli`.
+- Generated `fesa_solver.vcxproj` and `fesa_cli.vcxproj` contain
+  `<WarningLevel>Level4</WarningLevel>` and
+  `<TreatWarningAsError>true</TreatWarningAsError>` for Debug and the other generated
+  configurations.
+- The clean 74.713-second build recompiled the product and all test translation units;
+  its compiler/linker warning scan found `0` lines.
+- The exact post-configure build also exited 0 and found `0` warning lines.
+
+Result: no product warning was emitted, and any MSVC product warning would have failed
+the build under `/WX`.
+
+## Reference Read-Only Audit
+
+The following SHA-256 values were identical before and after all configure/build/test
+commands, while both reference diff checks exited 0 and both reference status checks
+were empty:
+
+| exact approved legacy path | SHA-256 |
+| --- | --- |
+| `reference/cantilever beam/cantilever beam.inp` | `E406EA9560321B791DB829E03BD24593B9875E0195D35B86BD931EDA122EF3` |
+| `reference/cantilever beam/cantilever beam displacements.csv` | `7B3312FBC8848E81D9A0FD4FF2B56BC1954636A2C14B5C1CBB269CB9477D3C31` |
+| `reference/cantilever beam/cantilever beam reactions.csv` | `BF30CDB0CD50106885DE14D63492737736C587426EBD787DE4F7EE6AA86DAA23` |
+| `reference/cantilever beam/cantilever beam elemental forces.csv` | `E5E77FEC0FA9482AE018DBF296E74D396335C7C711BD2E9AA2315247A34290BA` |
+
+## Failure Classification
+
+- classification: `N/A`
+- primary_failure: `N/A`
+- first_failed_command: `N/A`
+- evidence_tail: All required configure, build, discovery, feature-label, and full-test
+  commands exited 0; no failed test exists.
+- correction_handoff: `N/A`; no implementation-owned, environment, harness, or
+  upstream-contract failure requires correction.
+
+## Failed Test Inventory
+
+None. Feature-label CTest and full CTest both passed 83/83.
+
+## Handoff Recommendation
+
+| target_agent | reason | required_input |
+| --- | --- | --- |
+| Reference Verification Agent | Step 25 build/test gate is `pass-for-reference-verification`. | This report, HEAD `400db19`, `.harness/build/tests/Debug/fesa_reference_tests.exe`, and the unchanged exact legacy bundle. |
+
+The build-local Step 24 evidence exists at
+`.harness/build/reference/cantilever-beam-b33/results.h5` and
+`.harness/build/reference/cantilever-beam-b33/comparison.json`; the JSON is 128,118 bytes
+with SHA-256
+`258347AEA791D981AEA9B2BCAD85DE5344D4859ECA3692DC5E7AA01A848F8E0D`.
+Step 26 must independently rerun and inspect the approved comparison evidence. Its
+presence and CTest success here are not a reference-verification verdict.
+
+## No-Change Assertion
+
+- source_files_modified: `false`
+- test_files_modified: `false`
+- cmake_files_modified: `false`
+- requirements_or_upstream_contracts_modified: `false`
+- reference_artifacts_modified: `false`
+- tolerance_policies_modified: `false`
+- owned_report_modified: `true`
+- phase_index_step25_modified: `true`
+- notes: Before report/index creation the worktree was clean at the audited HEAD. Final
+  scope validation is limited to this report and the Step 25 fields in the phase index.
+
+## Open Issues
+
+- None blocking Reference Verification.
+- The implementation report aggregate `in-progress` header is noted above but does not
+  contradict its 18 completed Step blocks, the phase index, or the fresh build/test result.