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

On 27 July 2012 16:31, Anthony Liguori <aliguori(a)us.ibm.com&gt; wrote: > Peter Maydell <peter.maydell(a)linaro.org&gt; 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