This program prints "foo":

#include <stdio.h>
        
int main()
{       
    unsigned long long x, y;            
        
    x = 100;      
    y = 0x8000000000000000ULL;
    if (x > y) printf("foo\n");         
    return x > y; 
}       

This also causes the failures in test/src/libs/stdlib/001inttypes.c.