[Qemu-devel] Re: [PATCH 30/42] Rename CPPFLAGS to CFLAGS

[Paolo Bonzini <bonzini@gnu.org>]

> Ok, and what are that options?
> Looking at today Makefiles, the only things that I see that the user
> could want changing is:
>   -g
>   -O2
>   -fno-strict-aliasing
>   -fno-unit-at-a-time (ppc)
>   -msmall-data (alpha)
>   -mno-sdata (ia64)
>
> Rest of things are -I/-D stuff, that you don't want to touch from the
> command line at all.
>
> Anything else?  Should that be enough?

I'd say only "-g -O2".

-f and -m options should be left in QEMU_CFLAGS but CFLAGS should be 
expanded *after* it so that people can add 
-fstrict-aliasing/-funit-at-a-time/-mlarge-data/-msdata if they want to 
enable those options explicitly.

The rationale is that probably "make CFLAGS=-g" would break the build on 
PPC, Alpha, and IA64; and "make CFLAGS='-O3 -g'" would break the build 
everywhere due to the lack of -fno-strict-aliasing.

Paolo