fix: prefer compiler runtimes in Windows packages

[i386]

Fixes #1160

What changed

• discover the active MinGW compiler directory before PATH and Vulkan SDK directories
• pass the compiler directory ahead of SDK dependencies during Windows CPU/Vulkan packaging
• add a regression test proving the compiler runtime wins when DLL names collide

Root cause

The collector selected the first DLL by filename, and the Vulkan SDK directory was ahead of the compiler runtime. That could package an incompatible libstdc++/libgcc/winpthread closure into the artifact.

Validation

• python3 -m unittest discover -s scripts/tests -p "test*.py" (386 passed, 7 skipped)
• bash -n scripts/package-native-runtime.sh

Windows artifact loadability still needs validation on a clean Windows runner.

Summary by CodeRabbit

• Bug Fixes

  • Improved Windows CPU and Vulkan runtime packaging to select the correct compiler runtime libraries.
  • Prevented conflicting Vulkan SDK DLLs from being selected over the compiler’s required runtime DLLs.
  • Updated dependency discovery to prioritize the configured compiler location and system PATH before Vulkan SDK directories.

• Tests

  • Added regression coverage for correct runtime DLL selection when duplicate libraries are present.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: ce594a8a-ca12-405e-8cd8-438af16f1200

📥 Commits

Reviewing files that changed from the base of the PR and between a6db2fb and 0ce8703.

📒 Files selected for processing (1)

• scripts/package-native-runtime.sh

🚧 Files skipped from review as they are similar to previous changes (1)

• scripts/package-native-runtime.sh

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📝 Walkthrough

Walkthrough

Windows runtime dependency collection now searches the selected MinGW compiler directory before PATH and Vulkan SDK directories. Packaging resolves the compiler from configured variables or g++, and tests verify selection of the compiler-provided runtime DLL.

Changes

Windows runtime dependency resolution

Layer / File(s)	Summary
Prioritize compiler runtime directories scripts/windows-native-runtime-deps.py, scripts/package-native-runtime.sh	The resolver checks the first available g++ or gcc directory before PATH and Vulkan SDK directories. Packaging resolves the compiler from MINGW_CXX, CXX, or g++, and fails when an explicit compiler is unavailable.
Regression coverage scripts/tests/test_windows_native_runtime_deps.py	The test verifies that dependency collection selects and copies libstdc++-6.dll from the compiler directory instead of a conflicting Vulkan SDK copy.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Possibly related PRs

• Mesh-LLM/mesh-llm#963: Both changes prioritize MinGW compiler runtime libraries over Vulkan SDK copies.
• Mesh-LLM/mesh-llm#1046: This change extends the Windows Vulkan dependency resolution and regression coverage.

Suggested reviewers: ndizazzo

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly identifies the primary change: preferring compiler runtimes in Windows packages.
Linked Issues check	✅ Passed	The changes address #1160 by prioritizing the build compiler runtime and testing selection when DLL names conflict with Vulkan SDK copies.
Out of Scope Changes check	✅ Passed	All changes support the linked issue by updating Windows dependency resolution and adding targeted regression coverage.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch agent/fix-windows-runtime-dependency-abi

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[github-actions]

This pull request is currently a draft. Reviews will not take place until the PR is marked as ready for review.

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@scripts/package-native-runtime.sh`:
- Around line 461-470: Update the compiler lookup in the BACKEND cpu/vulkan
block to use the build-time resolved compiler path rather than passing the raw
MINGW_CXX or CXX value to command -v. Ensure wrapper or argument-containing
selections resolve correctly, and report or fail when an explicitly selected
compiler cannot be located instead of silently omitting its directory; preserve
the dependency_args search-dir addition for valid paths.

🪄 Autofix

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: c5294c9a-cd54-4b56-9d1b-b8d0f1f0c6a9

📥 Commits

Reviewing files that changed from the base of the PR and between 915e691 and a6db2fb.

📒 Files selected for processing (3)

• scripts/package-native-runtime.sh
• scripts/tests/test_windows_native_runtime_deps.py
• scripts/windows-native-runtime-deps.py