3.8.1.4 XC8 C Compiler - General

Figure 3-13. XC8 C Compiler - General
Use subroutines for function prologues and epilogues
This option affects how functions save and restore registers on entry and exit. See 3.6.1.3 Call-prologues Option.
Change the stack pointer without disabling interrupts
This option controls whether interrupts should be disabled when the stack pointer is changed. See 3.6.1.9 No-interrupts Option.
Default char type is unsigned
This option controls the signedness used for a plain char. See 3.6.3.8 Signed-char Option.
Default bitfield type is unsigned
This option controls the signedness used for a plain int bit-field. See 3.6.3.8 Signed-char Option.
Use CCI
Selecting this option indicates that source code should conform to the Common C Interface. See 3.6.3.4 Ext Option.