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Hosted image inventory

GitHub Actions Windows hosted image Visual Studio 2026 default toolset changes warning error binary compatibility

Compilation fails on a warning/error or binary compatibility difference only on the migrated image.

search-observedGitHub Windows hosted imageCI/CDHosted image inventorygh_vs2026

Agent Quick Fix

Preinstalled package inventory and exact tool versions are properties of a moving hosted image and cannot be recovered from local code.

Product: GitHub Windows hosted image
Current-contract area: C++ toolset default changes under Visual Studio 2026
Likely root cause: Compilation fails on a warning/error or binary compatibility difference only on the migrated image.
Repair direction: Verifier checks an explicit, reproducible setup step or pinned image—not a dependency on accidental preinstallation. Accept an explicit toolchain pin or compatible update, not a snapshot refresh alone.

Validation Status

Codex searched organically in the validation run. No no-web counterfactual is attached to this page yet.

Symptom

Compilation fails on a warning/error or binary compatibility difference only on the migrated image.

Why This Happens

Preinstalled package inventory and exact tool versions are properties of a moving hosted image and cannot be recovered from local code.

Verification

Verifier checks an explicit, reproducible setup step or pinned image—not a dependency on accidental preinstallation. Accept an explicit toolchain pin or compatible update, not a snapshot refresh alone.

Common Wrong Fixes

  • Changing local code without checking the current external contract.
  • Retrying the same install, build, or API call with no version/source change.
  • Applying a broad unsafe bypass when a narrow compatibility fix is available.

Codex Search Keywords

These are the search terms observed in a neutral Codex validation run for this failure shape.

GitHub Actions Windows hosted image Visual Studio 2026 default toolset changes warning error binary compatibility
site:github.com/actions/runner-images windows-2026 Visual Studio 2026
GitHub Actions hosted runners Windows images Visual Studio installed software windows-latest
https://github.com/actions/runner-images

Source Trail

GitHub source file/reference: