[DanielZhao0432]

Reminder

• I have read AGENTS.md and docs/developers_guide/agent_governance.md.
• I have linked an issue or explained why this PR does not need one.
• I have added adequate unit tests and/or case tests, or explained why not.
• I have listed the exact verification commands run and their results.
• I have described user-visible behavior changes, including INPUT parameter changes.
• I have explained core-module impact for ESolver, HSolver, ElecState, Hamilt, Operator, Psi, or other source/ changes.
• I have requested any needed governance exception below.

Linked Issue

Fix #8227

Unit Tests and/or Case Tests for my changes

• Commands run:
  1. Standalone CMake project exercising the exact new lookup block against mock
     mtfftblas prefixes, four scenarios (cmake -S <proj> -B <build> -DUSE_DSP=ON -DMTBLAS_FFT_DIR=<mock prefix>):
     • only libmtblasfftdev.a present (mtfftblas_v1.4.1c layout) → resolves to libmtblasfftdev.a
     • only libmtblasdev.a present (older mtfftblas layout) → falls back to libmtblasdev.a
     • both present → deterministically resolves to libmtblasfftdev.a (NAMES order)
     • neither present → configure aborts with the intended FATAL_ERROR message
  2. cmake -S . -B <build> with default options (USE_DSP=OFF) → configures and
     generates successfully; non-DSP builds unaffected.
  3. Real DSP build on Tianhe against mtfftblas_v1.4.1c, symlink workaround removed:
     cmake -DUSE_DSP=ON -DMT_CPACK_DIR=... -DMTBLAS_FFT_DIR=... ... →
     MTBLASDEV_LIB resolves to libmtblasfftdev.a; full compile and link succeed;
     the resulting binary runs LCAO calculations normally.
  4. python3 tools/03_code_analysis/agent_governance_check.py --staged → no findings.
• Result summary: all checks above pass.
• Checks not run, with reason: no unit/case tests added — the change is CMake build
  logic that the C++ test harness cannot exercise, and CI has no DSP toolchain;
  the DSP path was verified manually on Tianhe as listed above.

What's changed?

• mtfftblas_v1.4.1c renamed libmtblasdev.a to libmtblasfftdev.a, breaking DSP
  builds (-DUSE_DSP=ON) because the archive name was hardcoded in
  source/CMakeLists.txt. The link entry is now resolved with
  find_library(... NAMES mtblasfftdev mtblasdev PATHS ${MTBLAS_FFT_DIR}/libmtblas/lib NO_DEFAULT_PATH), accepting both the new and the legacy name, and configuration
  aborts with a clear diagnostic when neither exists.
• The archive keeps its position after the standalone BLAS/LAPACK/ScaLAPACK
  entries (required because the mtblas archives bundle their own OpenBLAS
  objects), and the separate C_PACK prerequisite is unchanged.
• User-visible change: DSP builds now work with both mtfftblas >= v1.4.1c and
  older mtfftblas releases without symlink workarounds. No INPUT parameter changes.
• Only the USE_DSP branch of source/CMakeLists.txt is touched; builds on
  other platforms are unaffected.

Governance Notes

• INPUT/docs changes: none (build-system only).
• Core module impact: none — no source/ C++ code changed.
• Exceptions requested: none.

[mohanchen]

LGTM