Porting 64-bit target on 32-bit host

[Huang Ping]

Hi, all

I'm porting a 64-bit target gcc on a 32-bit i386 host. I have set
need_64bit_hwint to yes in config.gcc. But it fails when building
libgcc.
Then I did a simple test. test case like this:
int test ()
{
   return 0;
}

I use cc1 compile it with -fdump-tree-all. The 003t.orioginal dump file shows:
{
   return 1900544;
}

I guess the compiler may take constant 0 as TImode, and read the
adjacent word in memory. But I'm not sure. Could someone give some
advice?
Thanks.

Ping