Re: [Qemu-devel] [PATCH 4/7] compiler: add macro for GCC weak symbols

[Peter Maydell <peter.maydell@linaro.org>]

On 27 July 2012 16:31, Anthony Liguori <aliguori@us.ibm.com> wrote:
> Peter Maydell <peter.maydell@linaro.org> writes:
>> My approach to this is to avoid non-standard things
>
> http://en.wikipedia.org/wiki/C99#Implementations
>
> So unless you plan on compiling QEMU with xlc, pgi, or icc, I don't
> think relying on "standard things" really helps.
>
> QEMU doesn't support C99, it supports GCC.

OK, you could perhaps rephrase that as 'mainstream' rather than
'standards-compliant'. I don't think we need to be strict C99;
I do think we have more than one working host OS and that patches
that use functionality that's documented not to work on all gcc
targets ought to come attached to a statement that they've been
tested. (MacOSX isn't actually in MAINTAINERS as a host so is
a bit of a red herring. Windows is listed.)

So if you really like weak symbols, go ahead. I'm just saying
you're imposing a bigger testing burden on yourself than if
you handled this some other way.

(I do think it would be nice to care about building with CLANG,
because there are some static analysis tools that we would
then be able to run. That doesn't mean dropping all GCC
extensions, though, because CLANG does support a lot of them.)

-- PMM