Besides, remove unused ASAN_OPTIONS from github workflows.
Further, activate sanitizers for C++23 workflows, at the places
where we also activated -O3 optimization. Not activating everywhere
for CI efficiency reasons for now.
Note that the sanitizers are activated on clang C++23 workflows
only, since there is a remaining issue with GCC in delegate_cpp11.
GitHub Actions runners now force Node.js 24; actions/checkout@v4 still targets Node.js 20 and triggers a deprecation warning. Pin all workflows to v6.0.3, the latest stable release with native Node.js 24 support.
Ubuntu 26.04 is not available in github workflows directly and won't be soon.
But ubuntu-26.04 is available as docker container. So use it for running
C++26 workflows which were disabled previously.
Includes C++26 related infrastructure macros.
Fixes compile errors when compiling under C++26.
Initially supported C++26 features:
- [[indeterminate]]
- new 2022 ISO prefixes in ratio.h
- atomic fetch_max() and fetch_min()
- is_virtual_base_of
- is_trivially_relocatable and trivially_relocate
- saturation arithmetic: add_sat, sub_sat, mul_sat, div_sat, saturate_cast
