[Qemu-devel] Re: [PATCH 00/37] Generate a proper LIBS variable

[Juan Quintela]

Paolo Bonzini <address@hidden> wrote:
>> ToDo:
>> - Make the same treatment for CFLAGS, CPPFLAGS and LDFLAGS.
>
> Cool!  For CFLAGS and CPPFLAGS, however, I'd suggest moving all flags
> that are necessary to build (such as -I as opposed to just -O, -g and
> the like) to QEMU_CFLAGS and QEMU_CPPFLAGS.  This way rebuilding
> without optimization can be done very easily.

My idea hera is to do diferently.  Actually he have a very confusing use
of CFLAGS.  My idea is:

--extra-cflags: remove it, we can use:

CFLAGS="foo bar" ./configure
(it is not there yet, but we can do it)

And we can use in each place that we modify CFLAGS:

CFLAGS="more stuff $CFLAGS"

Notice that the stuff that we invoked ./configure with comes last, as
we wanted for EXTRA_CFLAGS.

As an added bonus, we can compile all the tests in ./configure with that
variable set.

As for compiling a file with different options, we want something like
that for Makefile, i.e.

make all
rm foo.o
make CFLAGS=-O0 foo.o

compile with -O0 as last option, that way we can "overwrite" the -O2
that came from the config-hosts.mak

Doing the configure bits are easy (just work), as for the Makefile
stuff, instead of having

CFLAGS+=foo

printed on config-hosts.mak

just print:

CFLAGS=foo $(CFLAGS)

should make the trick.

We got more functionality that we have today, and we can:
- remove extra-cflags
- we don't need to OPT= variable that Blue Swirl wanted

What do you think?

Later, Juan.