[rurban]

Nope. Practically gcc and clang are available for all platforms, and for the rare cases someone uses another compiler or an old version you ifdef it out with the slow path. even ICC has the add/mult with carry overflow builtins.

The ISO C standard is hopelessly behind for decades. They don't even define a proper (unicode) string API (search, norm, utf8, fc) , constexpr, a memory model, ... and leave everything to the implementors.

[pjmlp]

I very much doubt that, specially since clang doesn't even cover all gcc supported architectures.

Additionally, being available doesn't mean it is the compiler one is allowed to use.

Apparently you haven't kept up with ISO C, C11 defined the memory model and portable threads. It is unfortunate that compiler vendors, specially your beloved gcc and clang disregard the security Annex K.

[rurban]

beloved gcc? I despise gcc for not being able to provide a proper constexpr in C, making memcpy, memset 2x slower than clang.