Trouble eliminating padding or alignments

[Alex Buell <alex dot buell at munted dot org dot uk>]

Hi!

I'm currently working on a small project that involves building a flat
binary image as a 512 byte bootloader under Linux and tested on a
virtual machine.

The bootloader consists of an asssembly file (boot.asm) compiled by NASM
into an ELF32 object. The linking process also pulls in routines from a
library containing NASM ELF32 object files.

Previously, with all routines in one assembly file, it always generates
a binary less than 448 bytes. 

Unfortunately when I needed to share some common routines with another
NASM assembly routine, I put these into its own common library archives,
used AR with 'rcs' options, but the linker now generates a flat binary
larger than it needs to be (568 bytes instead of being less than 448
bytes). And yes, I'm using --oformat binary. 

On investigating with hexdump, I realised that there were extra bytes
inserted into the object files and the library archive, perhaps because
it thinks it needs to be aligned or padded, something like that.

I tried using --as-needed and -s options with the linker but it seems to
make no difference.

Is there anything I can do to eliminate these additional alignment or
padding bytes? Any help given would be much appreciated.
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