[tirlarim]

Summary

iOS defines __APPLE__, so SystemMonitor.cpp selects the macOS backend and fails to compile against the iPhoneOS SDK at IOKit/graphics/IOGraphicsLib.h.

• Include TargetConditionals.h explicitly and select the macOS backend only when TARGET_OS_OSX is true. iOS uses the existing empty monitor implementation.
• Link the desktop monitor frameworks only for macOS (CMAKE_SYSTEM_NAME is Darwin), in both the library and CPU tests.
• Apply the same platform distinction to the existing virtual display tests.

Fixes #2362.

Validation

Tested with Apple Clang 21.0.0 and the Xcode 27.0 SDKs on Apple Silicon.

• Reproduced the missing IOGraphicsLib.h error by cross-compiling the original SystemMonitor.cpp for iOS.
• Cross-compiled the patched SystemMonitor.cpp and Config_tests.cpp to arm64 object files for both iOS 27.0 devices and the iOS 27.0 simulator.
• Built the native macOS shared library and CPU tests in RelWithDebInfo, with SIMD disabled. Confirmed the macOS backend and desktop framework linkage are retained.
• Ran ctest --test-dir build/codex-macos-apple --output-on-failure: test_utils_exec passed; 1173 of 1175 CPU tests passed. The two numerical tolerance failures below also occur on the unmodified main commit (22dd9c4) using the same build configuration:
  • OpOptimizers/gamma_comp_test2
  • GammaOpCPU/apply_moncurve_mirror_style_fwd
• Ran the complete Config CPU test group separately; all tests passed, including the virtual display tests.
• git diff --check passed.

The iOS checks compile the affected translation units; a complete iOS library build and device execution have not been performed.

[linux-foundation-easycla]

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• ✅ login: tirlarim / name: Stanislav Romanov (7082db0)