Also test on MSVC with error-checked standard library

[MungoG]

Summary by CodeRabbit

• Chores
  • Updated CI/CD pipeline configuration to improve build consistency across different compiler variants, particularly for MSVC builds.

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[coderabbitai]

📝 Walkthrough

Walkthrough

The GitHub Actions CI workflow configuration has been updated to modify how MSVC builds are tested. For MSVC compilers, the matrix now uses combined debug and release build variants instead of the direct matrix.build-type, while non-MSVC compilers maintain the original behavior.

Changes

Cohort / File(s)	Summary
CI Workflow Configuration .github/workflows/ci.yml	Modified MSVC build matrix to use combined "debug,release" build-variant instead of matrix.build-type; non-MSVC compilers unchanged

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

Poem

🐰 A workflow refined with surgical care,
Debug and release, a test-variant pair,
For MSVC's march through the pipeline so fast,
CI gates stand stronger, quality held fast! ✨

🚥 Pre-merge checks | ✅ 2

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title 'Also test on MSVC with error-checked standard library' directly relates to the main change: MSVC builds now use a combined debug and release variant for expanded testing coverage.

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[cppalliance-bot]

An automated preview of the documentation is available at https://68.corosio.prtest3.cppalliance.org/index.html

If more commits are pushed to the pull request, the docs will rebuild at the same URL.

2026-01-23 10:18:21 UTC

[coderabbitai]

Actionable comments posted: 1

🤖 Fix all issues with AI agents

In @.github/workflows/ci.yml:
- Around line 360-363: The workflow passes "debug,release" into the
build-variant input (via build-variant: ${{ (matrix.compiler == 'msvc' &&
'debug,release') || matrix.build-type }}) but the alandefreitas/cpp-actions
b2-workflow expects a single variant string; change the matrix to include a
dedicated matrix key (e.g., matrix.build-variant) with separate values "debug"
and "release" for MSVC and update the action invocation to use build-variant:
${{ matrix.build-variant }} (or map matrix.compiler to a single build-variant
per job) so each job runs one valid variant at a time.

[coderabbitai]

⚠️ Potential issue | 🔴 Critical

🧩 Analysis chain

🌐 Web query:

alandefreitas/cpp-actions b2-workflow build-variant input format documentation

💡 Result:

In alandefreitas/cpp-actions → b2-workflow, the build-variant input is a single string naming the build variant. The action accepts CMake-style build types and maps them to B2, or you can pass a custom B2 variant name directly: Release → release, Debug → debug, RelWithDebInfo → release plus debug-symbols=on, and anything else is lowercased and used as the B2 variant. If build-variant is not set, it falls back to B2_BUILD_VARIANT, otherwise to build-type. [1]

Related: in B2 itself, the built-in variant feature’s standard values are debug and release. [2]

Sources
[1] B2 Workflow action docs (build-variant mapping and fallback rules) (alandefreitas.github.io)
[2] B2 manual (variant values) (bfgroup.xyz)

Citations:

• 1: https://alandefreitas.github.io/cpp-actions/cpp-actions/actions/b2-workflow.html
• 2: https://www.bfgroup.xyz/b2/manual/release/index.html?utm_source=openai

---

The build-variant input expects a single variant string, not comma-separated values.

Line 362 passes debug,release to build-variant, but the alandefreitas/cpp-actions b2-workflow action accepts only a single variant per invocation. B2 will treat debug,release as a literal variant name (which does not exist) and the build will fail or skip the intended variants. To build both debug and release for MSVC, use a matrix strategy to invoke the workflow multiple times with separate build-variant values.

🤖 Prompt for AI Agents

In @.github/workflows/ci.yml around lines 360 - 363, The workflow passes
"debug,release" into the build-variant input (via build-variant: ${{
(matrix.compiler == 'msvc' && 'debug,release') || matrix.build-type }}) but the
alandefreitas/cpp-actions b2-workflow expects a single variant string; change
the matrix to include a dedicated matrix key (e.g., matrix.build-variant) with
separate values "debug" and "release" for MSVC and update the action invocation
to use build-variant: ${{ matrix.build-variant }} (or map matrix.compiler to a
single build-variant per job) so each job runs one valid variant at a time.