how can i generate S flag to see myproject.S machine code .TWO problems the sencond avoid temporals erasing to see ie: myproject.S as in gcc?
Not an Arduino Question!
I would disagree.
In order to see the assembler output you will have to modify the build rules in the platform.txt.
Life sucks on Windows, but it is pretty easy to use a wrapper script around a tool trick the IDE into automatically creating the files you want.
If you using AVR and are on a *nix platform, I can provide you with some assistance with a script that wraps
avr-objcopy that runs the appropriate tools to generate the assembly listing and link maps from the elf file before running avr-objcopy