All the C types have had minimum allowed ranges going back to ANSI C. For 'char', it must at least support the range 0 to 127 (and in addition, it must have th

All the C types have had minimum allowed ranges going back to ANSI C. For 'char', it must at least support the range 0 to 127 (and in addition, it must have the same range as either 'unsigned char' or 'signed char').