Hmmm, checked some old code. All voids, no ints. Works over here.
#ifdef SAS_C
int CXBRK(void) { return(0); }
void __regargs __chkabort(void);
void __regargs __chkabort(void) {}
#endif
Edit:Btw I thought you developed AA with Stormc (looking at the code). Why bother with sas/c

Ran the latest version of it (16.02) and found
no problem with CTRL-C. It says 'Quitting.' and exits the program normally.