The CMake build system generated by cmsis-toolbox has inconsistent support for some standards:
The GNU variants for C standards c17 (gnu17) and c23 (gnu23) are missing. This is unexpected, since the non-GNU variant is supported
The C++ standards c++20 and gnu++20 are incorrectly mapped to c++17 and gnu++17, leading to confusing behaviour. Either c++20 should be accepted and lead to actual C++20 support being enabled in the compiler, or c++20 should be rejected. Accepting c++20 and silently downgrading to c++17 is confusing.
As an additional enhancement, the following missing language standards should be added:
c++23
gnu++23
To Reproduce
Specify language-C: gnu17 or language-C: gnu23 in a .cproject.yml file and attempt to build the project. The build fails with unknown 'language' value 'gnu17' !.
Specify language-CPP: c++20 or language-CPP: gnu++20 in a .cproject.yml file and attempt to build a project containing C++20 features (such as requires clauses). The build fails with C++ syntax errors due to the mode not being C++20.
Expected behavior
Language standard support should be consistent and either correctly passed to the compiler or not implemented.
Environment (please complete the following information):
Describe the bug
The CMake build system generated by
cmsis-toolboxhas inconsistent support for some standards:c17(gnu17) andc23(gnu23) are missing. This is unexpected, since the non-GNU variant is supportedc++20andgnu++20are incorrectly mapped toc++17andgnu++17, leading to confusing behaviour. Eitherc++20should be accepted and lead to actual C++20 support being enabled in the compiler, orc++20should be rejected. Acceptingc++20and silently downgrading toc++17is confusing.As an additional enhancement, the following missing language standards should be added:
c++23gnu++23To Reproduce
Specify
language-C: gnu17orlanguage-C: gnu23in a .cproject.yml file and attempt to build the project. The build fails withunknown 'language' value 'gnu17' !.Specify
language-CPP: c++20orlanguage-CPP: gnu++20in a .cproject.yml file and attempt to build a project containing C++20 features (such asrequiresclauses). The build fails with C++ syntax errors due to the mode not being C++20.Expected behavior
Language standard support should be consistent and either correctly passed to the compiler or not implemented.
Environment (please complete the following information):
cmsis-toolbox 2.6.0armclang 6.21.0Additional context
New issue as suggested in #1703.