Clang cannot find C++ header files on 24.04

[K20shores]

Description

Following the update of ubuntu-latest updating to Ubuntu 24.04, Ubuntu workflows with clang started failing to build. It seems that Clang cannot find the header files for much of the C++ standard library.

Anything failing on 20.04 is a non issue because we weren't really targeting that. However, clang on 24.04 does not seem to find the C++ header files.

Platforms affected

• Azure DevOps
• GitHub Actions - Standard Runners
• GitHub Actions - Larger Runners

Runner images affected

• Ubuntu 20.04
• Ubuntu 22.04
• Ubuntu 24.04
• macOS 12
• macOS 13
• macOS 13 Arm64
• macOS 14
• macOS 14 Arm64
• macOS 15
• macOS 15 Arm64
• Windows Server 2019
• Windows Server 2022
• Windows Server 2025

Image version and build link

I put together an action which builds our software with gcc/clang in debug/release on 20.04, 22.04, 24.04, and latest so I can see where we are failing. The action.

Is it regression?

Yes

Expected behavior

Clang finds c++ header files

Actual behavior

Clang doesn't find c++ header files

Repro steps

Create a project which uses C++ on Ubuntu 24.04 and try to compile it with clang

[vidyasagarnimmagaddi]

Hi @K20shores , Thank you for bringing this issue to our attention. We are looking into this issue and will update you on this issue after investigating.

[subir0071]

Hi @K20shores - As per reproduction steps we created a minimal CPP project and executed the workflow , but the workflow passed as expected.

Let us know if missing something.

[K20shores]

@subir0071 Your action uses the GCC compiler. Please use the clang compiler. I updated my reproduction steps to represent this. Sorry for the confusion. I see this issue with the clang compiler.