The C Standard doesn't guarantee support for -128 and -32768. This originally
was for ones' complement machines such as the Unisys ClearPath Dorado
enterprise servers (still in use via firmware translation to Intel Xeon, and
they have a C compiler),
Are they still used in production for programs written in C?
Yes, it does appear C is still active there; Unisys has a C reference manual
dated 2015
<https://public.support.unisys.com/aseries/docs/clearpath-mcp-17.0/pdf/86002268-206.pdf>
and they're still selling those mainframes with new hardware released this year
<https://www.app5.unisys.com/library/gmMail/emails/documents/CP-June19/poweredby_june2019.html>.
PS. They also support Cobol, Fortran, and some other languages. (The world is
still waiting patiently for Bison to support Cobol. :-)
