320-vararg-cap.c (1032B)
1 /* Variadic save area is capped at 32 incoming-argument words (named + 2 * variadic). cg should reject calls that exceed this cap with a clear 3 * compile-time error rather than silently miscompile by writing past 4 * the save area in the callee's prologue. 5 * 6 * This test exercises the Kit-motivated range above the old 16-word cap: 7 * 1 named + 19 variadic = 20 args total. Sum 1..19 = 190. */ 8 9 #ifndef CCSCM 10 #include <stdarg.h> 11 #else 12 typedef char *va_list; 13 #define va_start(ap, n) __builtin_va_start(ap, n) 14 #define va_arg(ap, t) __builtin_va_arg(ap, t) 15 #define va_end(ap) __builtin_va_end(ap) 16 #endif 17 18 int sum(int n, ...) { 19 va_list ap; 20 int total; 21 int i; 22 va_start(ap, n); 23 total = 0; 24 i = 0; 25 while (i < n) { 26 total = total + va_arg(ap, int); 27 i = i + 1; 28 } 29 va_end(ap); 30 return total; 31 } 32 33 int main(void) { 34 /* 19 variadic ints; n itself is named arg 0; total 20 args. */ 35 return sum(19, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 36 11, 12, 13, 14, 15, 16, 17, 18, 19); 37 }