Mixed optimization and pragma settings cause ‘__open_too_many_args’ compile error

Sample program below compiles with gcc with no errors, but results with a compile error with g++

g++ version: 4.8.2-19ubuntu1

gcc -O2 prog.c # ok
g++ -O2 prog.c # error

In file included from /usr/include/fcntl.h:279:0,
                 from prog.c:5:
In function ‘int open(const char*, int, ...)’,
    inlined from ‘int main()’ at prog.c:12:40:
/usr/include/x86_64-linux-gnu/bits/fcntl2.h:44:28: error: call to ‘__open_too_many_args’ declared with attribute error: open can be called either with 2 or 3 arguments, not more
     __open_too_many_args ();

Sample program:

#pragma GCC optimize ("O0")

#include <fcntl.h>
#include <unistd.h>

int main()
{
 int fd;

 fd = open( "filename", O_RDONLY, 0644);
 if (fd < 0) return 1;

 close(fd);

 return 0;
}