IIRC they were also available as “non-standard” feature in compilers at the time before being added to c99 (e.g. I’m pretty sure gcc in the late 90s supported a

IIRC they were also available as “non-standard” feature in compilers at the time before being added to c99 (e.g. I’m pretty sure gcc in the late 90s supported all of these if you didn’t force c89 compatibility).