built-in.md

Built-in function

• https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html
• https://gcc.gnu.org/onlinedocs/gcc/Target-Builtins.html

Many GCC special functions and macros are prefixed __builtin_.

Those which are ANSI C functions, also have versions without __builtin_, but only the __builtin_ version can be used e.g. for C99 built-ins with -std=c89.