It seems the problem is g++ modified the symbol name of perl API provided by perl headers, so I tried to surround perl headers within extern: 
extern "C" {
#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#include "ppport.h"

#include <stdio.h>
}

[download]
But this does not help at all...

In reply to Re^4: Problem on XS by llancet
in thread Problem on XS module loading by llancet

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