Summary

Part of Phase 3 (C++20 Module Stabilization) from #275.

Verify that all unit tests pass with module build enabled (-DCOMMON_BUILD_MODULES=ON).

Parent Issue

• [MODULE] Phase 3: C++20 Module Stabilization #275 (C++20 Module Stabilization)
• EPIC: [EPIC] C++20 Module Migration - Cross-System Preparation #256

Tasks

• Verify all unit tests pass with module build on supported compilers
• Run integration tests with modules enabled
• Test cross-module imports
• Verify header-only build still works (backward compatibility)

Acceptance Criteria

• All existing tests pass with -DCOMMON_BUILD_MODULES=ON
• No regression in header-only build
• Test results documented

Notes

• AppleClang does not fully support modules - skip on macOS CI
• Focus on Clang 16+, GCC 14+, MSVC 2022