Object generation file using arm-elf, differences between gcc 3.2.1and 4.1.0

[Francesco Regazzoni <regazzoni at alari dot ch>]

Hi,

I have a question regarding the differences in the object files
generated using different versions of gcc. I'm using gcc-3.2.1 and
gcc-4.1.0, both crosscompiled for target arm-elf to compile a simple
hello world example.

1) The first version is gcc-3.2.1 compiled using this options:

Reading specs from /opt/gcc/bin/../lib/gcc-lib/arm-elf/3.2.1/specs
Configured with: ../CrossSources/gcc-3.2.1/configure --target=arm-elf
--prefix=/opt/gcc/ --enable-languages=c,c++ --with-gnu-as --with-gnu-ld
--with-newlib --with-gxx-include-dir=/opt/gcc/arm-elf/include
--disable-checking -v
Thread model: single
gcc version 3.2.1

and when I run the command: arm-elf-gcc-3.2.1 hello.c -o hello, it
generates a file of 343K.


2) The second version is gcc-3.2.1 compiled using this options:

Using built-in specs.
Target: arm-elf
Configured with: /home/regaz/Dottorato/gcc/sources/gcc/configure
--target=arm-elf --prefix=/opt/gcc/ --enable-languages=c,c++
--with-gnu-as --with-gnu-ld --with-newlib
--with-gxx-include-dir=/opt/gcc/arm-elf/include/ -v
Thread model: single
gcc version 4.1.0 20050516 (experimental)

and when I run the same command: arm-elf-gcc-4.1.0 hello.c -o hello, it
generates a file of 171K.


I would like to ask which one are the main differences in the object
file generated, and if is possible (using some compiler options) to
generate the same object file of version 4.1.0 using the version 3.2.1


Thanks!

-- 
Francesco Regazzoni,
PhD student at ALaRI - USI, Lugano [http://www.alari.ch]