why gcc-4.9.0 create larger files on 32bits system than 64btis.

[xinglp <xinglp@xxxxxxxxx>]

For example, on my newly built lfs system:
$ ls -lh {2014-04-27-3.14.1-x86_64,2014-04-27-3.14.1-i686}/bin/{xz,bash,sync}
-rwxr-xr-x 1 root root 806K Apr 26 23:54 2014-04-27-3.14.1-i686/bin/bash
-rwxr-xr-x 1 root root 747K Apr 27 04:25 2014-04-27-3.14.1-x86_64/bin/bash
-rwxr-xr-x 1 root root  22K Apr 26 23:54 2014-04-27-3.14.1-i686/bin/sync
-rwxr-xr-x 1 root root  24K Apr 27 04:25 2014-04-27-3.14.1-x86_64/bin/sync
-rwxr-xr-x 1 root root  67K Apr 26 23:54 2014-04-27-3.14.1-i686/bin/xz
-rwxr-xr-x 1 root root  64K Apr 27 04:25 2014-04-27-3.14.1-x86_64/bin/xz
The "i686" version files are bigger than the "x86_64". Why ?

Thanks.