[sanitizer] Fix mallopt test on Android.
There is not a single common mallopt option between gnu/linux and
android, so simply use a random number there.
#include <malloc.h>
int main() {
- int res = mallopt(M_ARENA_MAX, 0);
+ // Try a random mallopt option, possibly invalid.
+ int res = mallopt(-42, 0);
assert(res == 0 || res == 1);
}
