[ioccc] fix signature in annotation

ioccc/.frama-c/2019_yang_violet.parse/framac.ast

@@ -61,8 +61,7 @@ void s(void)
   return;
 }
 
-/*@ assigns \result;
-    assigns \result \from \nothing; */
+/*@ assigns \nothing; */
 void m(int p_0, int q_0)
 {
   _ d_0 = (p_0 + q_0) / 2;

ioccc/2019/yang/violet.c

-//@ assigns \result \from \nothing;
-int m(int, int);
+//@ assigns \nothing; //unsound
+void m(int, int);
                                            #include<stdio.h>
                                 #/*     [bbde3cf3]*/include<stdlib.h>
                              #  define D(o,l,I)/*( C ) 2 0 1 9 */o##l##I/*