Thanks for the suggestions, Tim.
I have tried to add  -ftree-vectorize to the gcc compilation with -O3, but it did not make and significant change in the code size. It seems that auto vectorization is already enabled with -O3 on gcc.
http://gcc.gnu.org/projects/tree-ssa/vectorization.html

The other tip regarding template inlining was quite frutitful, by setting
-inline-level=0
I could reduce the icc's -O3 binary size down to 2.2 MB, which is easier to swallow.

The C++ binary is still big compared to C. One of my other projects has 100.000 lines of C code, and yet it only makes a 1.4 MB binary, compiled with -O3, both with ICC as with GCC. So C++ base binary of comparable source size and optimization levels will  still be roughly 3 times bigger than C. I wonder if other people have the same experience, or I am doing somethign wrong.

Dušan Peterc
http://www.arahne.si