Re: [Qemu-devel] [PATCH] configure: Disable (clang) initializer-overrides warnings

[Stefan Weil <sw@weilnetz.de>]

Am 27.10.2012 23:35, schrieb Peter Maydell:
> On 27 October 2012 22:24, Stefan Weil<sw@weilnetz.de>  wrote:
>> Am 27.10.2012 22:32, schrieb Igor Mitsyanko:
>>> I encountered strange behavior of latest mingw gcc, it ignores
>>> unrecognized -Wno-wombat options only in case if no other warnings are
>>> issued (configure gccflags test doesn't issue any), otherwise I get this:
>>>
>>> cc1.exe: warning: unrecognized command line option
>>> "-Wno-initializer-overrides" [enabled by default]
>>>
>>> This is probably a bug in mingw GCC (or perhaps I'm using it wrong), but
>>> anyway, this makes QEMU mingw build output very noisy.
>> This "feature" of gcc is not restricted to MinGW nor to a special version of
>> gcc but can also occur on Linux.
>
> Incidentally, I was tangentially involved in getting gcc to adopt
> this behaviour. The rationale is that it allows you to write
> straightforward makefiles which use -Werror and also some -Wno-*
> options without having to add some configure-like step to test
> whether gcc supports the -Wno-*. If the gcc version you're using
> doesn't support detecting the presence of wombats in your source
> code then it will never produce warnings about them, so it's
> safe for it to treat -Wno-wombat as a no-op. The reason for
> printing the message if some other warning is also emitted is
> so the user can spot the case where they accidentally typo'd
> the -Wno-* option they meant to use to suppress the warning.
>
> -- PMM

Nice. Thanks for that explanation.

Are there plans to add wombat detection to gcc? :-)

Here is the spec:
http://upload.wikimedia.org/wikipedia/commons/1/18/Vombatus_ursinus_-Maria_Island_National_Park.jpg

Stefan