re: long longlong in libffi (powerpc)

Tue Jan 21 11:18:00 GMT 2003

=?iso-8859-1?Q?Andreas=5FTobler?= writes:
 > To follow up. (Sorry can't quote, webmail)
 > 
 > The problem I have is also visible on powerpc-linux.
 > 
 > Given this testcase:
 > 
 > static void closure_test_fn4(ffi_cif* cif,void* resp,void** args,
 > void* userdata)
 > {
 > *(ffi_arg*)resp =
 > (int)*(long *)args[0] +(*(int *)args[1]) +
 > /* (int)(*(float *)args[2]) + *(int *)args[3]*/ + (int)(long)userdata;
 > 
 > printf("%d %d %d %d: %d\n",
 > (int)*(long *)args[0], (*(int *)args[1]),
 > /* (int)(*(float *)args[2]), *(int *)args[3],*/ (int)(long)userdata,
 > *(int*)resp);
 > }
 > 
 > typedef int (*closure_test_type4)(long, int);
 > 
 > I run it with this definition:
 > 
 > cl_arg_types[0] = &ffi_type_ulong;
 > cl_arg_types[1] = &ffi_type_uint;
 > cl_arg_types[2] = NULL;
 > 
 > Here I get a failure since ulong is 'mapped' onto longlong (8bytes)
 > 
 > setting the arg[0] type to &ffi_type_uint32 makes the testcase pass.
 > 
 > So I'm a bit confused. My long is 4 byte, my longlong 8. And the ABI from
 > sysv & darwin handles the long and the longlong different. (long !=longlong)
 > 
 > 
 > Do I follow a phantom or my one explain to me what I forget?
SIZEOF_LONG is determined by an autoconf test. Here it is:
--------------------------------------------------------------------------------------
echo $ac_n "checking size of long""... $ac_c" 1>&6
echo "configure:3135: checking size of long" >&5
if eval "test \"`echo '$''{'ac_cv_sizeof_long'+set}'`\" = set"; then
 echo $ac_n "(cached) $ac_c" 1>&6
else
 for ac_size in 4 8 1 2 16 12 ; do # List sizes in rough order of prevalence.
 cat > conftest.$ac_ext <<EOF
#line 3141 "configure"
#include "confdefs.h"
#include "confdefs.h"
#include <sys/types.h>
int main() {
switch (0) case 0: case (sizeof (long) == $ac_size):;
; return 0; }
EOF
if { (eval echo configure:3151: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
 rm -rf conftest*
 ac_cv_sizeof_long=$ac_size
else
 echo "configure: failed program was:" >&5
 cat conftest.$ac_ext >&5
fi
rm -f conftest*
 if test x$ac_cv_sizeof_long != x ; then break; fi
done
fi
--------------------------------------------------------------------------------------
Please try to figure out if this is returning the wrong answer, and if
so why. It could be s shell bug.
Andrew.