test14.c: In function 'func1':
test14.c:12:8: warning: Using variable 'a' without checking for null pointer
     *a = 100;
        ^
test14.c: In function 'func5':
test14.c:45:8: warning: Using variable 'a' without checking for null pointer
     *a = 600;
        ^
test14.c: In function 'func7':
test14.c:70:11: warning: Using variable 'aptr' without checking for null pointer
     *aptr = 800;
           ^