[geocar]

I start with:

    -Os

I really don't like the stack protector. It adds a lot of space to executables, so I turn it off:

    -fno-stack-protector

Arthur told me about:

    -fno-asynchronous-unwind-tables

which seems to save a lot of space. I don't know exactly what it does, but the documentation suggests it does something with debugging, however `-s` doesn't remove it so I have this here.

I often work without glibc (don't need it) but I like gcc's builtins so I have:

    -Dabort=__builtin_trap -Dmemcpy=__builtin_memcpy -Dmemset=__builtin_memset -minline-all-stringops -msse2 -ffreestanding -nostdlib -fno-builtin

which seems to do the trick. I don't think all of these are necessary on all versions of GCC but I keep running into versions that complain about something so this line keeps getting longer. On x86 I additionally use:

    -mregparm=3

since it saves a lot of space and helps benchmarks.

[astrange]

For any benefit you'd get from -mregparm, you'd get a much better one by switching to amd64 already! Or are you having to support Windows?

[geocar]

X32 isn't quite everywhere yet, and the larger words add a lot of space. I try not to use them if I don't need it, but I'm definitely looking forward to X32.