CI: update with latest compilers

[DimitriPapadopoulos]

CircleCI images based on Ubuntu 26.04 should be available:

• Ubuntu 22.04, 24.04, 26.04 - Q2 2026 Edge Release (Including CUDA)
• Ubuntu 22.04, 24.04, 26.04 - Q2 Current Release (Including CUDA)

Not sure what the relation between cimg/base images such as cimg/base:current-24.04 and images like ubuntu-24:04:current could be.

[kevina]

Pull requests like this are not helpful and take me more time to review than to just do myself. My main goal is to make sure Aspell compiles on a wide range of compiler versions (both GCC cnd Clang) including the latest and and compilers found only any system with extended (even if paid) support.

Please first open an issue to discuss any changes.

[DimitriPapadopoulos]

Similar compiler versions are used across multiple images (g++-4.7/g++-4.8, g++-5, g++-9, g++-10, clang-6.0), so the main goal was not that obvious.

It's true that part of the more recent releases of the compilers can probably be tested from the existing cimg/base:current-24.04 image. The compilers that need to be tested are:

• g++-15
• g++-16
• g++-14-multilib → g++-16-multilib?
• clang-20 (move from snapshots to cimg/base:current-24.04?)
• clang-22 (probably in snapshots)

I am happy to help if you want me to. However, you probably have information that I don't have on how you wish to distribute compiler releases over images. You may also choose to close this PR, I have no problem with that.

[DimitriPapadopoulos]

I have updated the compilers. The following compilers remain untested, but it's not straightforward without an Ubuntu 26.04 image:

• g++-15
• g++-16

Also, it would probably be nice to test on Ubuntu 26.04, and perhaps stop testing on Ubuntu 20.04, but again cimg/base:current-26.04 is not available yet.

[kevina]

Thanks for understanding.

I'll keep this open as a reminder to update to newer compiler versions.