Freestanding standard library
Summary
The post explains freestanding in C++ as the subset that runs without a hosted operating system, contrasts it with hosted implementations, and notes the macro __STDC_HOSTED__. It identifies which standard library components are guaranteed in freestanding (e.g., <cstdint>, <cstddef>, <limits>, <type_traits>, parts of <new>) and which are typically unavailable (such as <thread> and <filesystem>, and often exceptions), then describes ongoing expansions from C++20 through C++26 to broaden freestanding support for embedded contexts.