>> And what kinds of source/kconfig changes are made for every build? > > I start with a baseline config for an embedded board, then > alter, one at a time, individual config items related to kernel size. > No source changes are made. Using same `gcc -E` principle, I once had a dream to create build with something like "whole-kernel-at-time" optimising compiler option: for file in $all_core_files do gcc $opt -E $file >>core_kernel.c done && gcc $opt code_kernel.c -o vmlinux.c.o # same for some special parts and asm do_foo # do final link do_vmlinux I've had something like that once for `dash` and had few percents of size reduction. It would be interesting to implement and check this in linux. Also i've many things to point-tune/point-remove based on usage patterns/source patterns, which can be easily removed by stream text editor from sources. These like not needed * syscalls,sysctl, ioctls * fields in data structures/sources for handling them * code branches or code blocks which are known (in particular board / embedded case) to be useless etc. etc. But all this requires non trivial source text editor or visual tools for easy analysis, navigation, marking, RE generation and build + run testing. With mid-70 command line and `make` (even kbuild version) or 20++ years old technology of text editors, it's not that trivial to accomplish. Some kind of IDE for kernel development is needed. Here one will have all whitespace and code style policy, static checks for stupid security holes, C mis-use, kernel API mis-use, all those crutches in linux/scripts/* in one place and applied right away. Sorry, for this rant, but i see no developemnt here at all. New schedulers, slab allocators, file systems are great. But all this has nothing to do with fundamental developent of the tools. Hardware is quite fast and have pretty much of RAM/ROM/caches now, yet software just bloats. The streaming, pre-cc text editing is the key, fine GCC is not. -- sed 'sed && sh + olecom = love' << '' -o--=O`C #oo'L O <___=E M -- To unsubscribe from this list: send the line "unsubscribe linux-embedded" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
