User defined function weirdness

Hi
    On postgresql 6.4.2 running on digital unix 4.0d. This bit of code

--------- pfunc.c-----------
/*
cc -c -I/usr/local/pgsql/include pfunc.c
ld -shared -expect_unresolved '*' -o pfunc.so pfunc.o
cc -o pfunc -I/usr/local/pgsql/include pfunc.c


create function int10() returns int4 as '/path/pfunc.so' LANGUAGE 'c';
create function float10() returns float4 as '/path/pfunc.so' LANGUAGE 'c';


select int10(),10::int4,float10(),10::float4;

*/
#include <stdio.h>
#include "postgres.h"                   /* for char16, etc. */

int4 int10() {
    return  (int4) 10;
}

float4 float10() {
    return  (float4) 10.0;
}
----------------------------

does


dbase=> select int10(),10,float10(),10.0;
int10|?column?|float10|?column?
-----+--------+-------+--------
   10|      10|2.27828|      10
(1 row)

dbase=>  select int10(),10,float10(),10.0;
int10|?column?|float10|?column?
-----+--------+-------+--------
   10|      10|2.27812|      10
(1 row)



Note that float10() gives different answers at different times.

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