why does arm-target gcc-3.4.4 have a better performace than gcc-4.2.4?

[Heyu Zhu <zhu.heyu@xxxxxxxxx>]

Hi, everyone

I configure gcc as below

../gcc-4.2.4(or gcc-3.4.4)/configure
               --target=arm-elf
               --prefix=/usr/local/arm
               --enable-languages=c
               --without-headers
               --with-gnu-ld
               --with-gnu-as
               --disable-shared
               --disable-threads
               --disable-libssp

 Executable binary file generated by gcc-3.4.4 is 15% faster than by
gcc-4.2.4 for some test programs, for example, Dhrystone.

Need i configure gcc-4.2.4 with special options to get a good
performace as gcc-3.4.4 does?

Thanks