[Qemu-devel] [PATCH, RFC] ld flag --warn-common

[Qemu-devel] [PATCH, RFC] ld flag --warn-common

[Blue Swirl]

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Hi,

These trivial patches enable linker flag --warn-common and fix the
warnings caused by enabling the flag.

I think on some platforms (Solaris?) the linker used by gcc is not GNU
ld. If this is true, the patch would break compilation on those hosts
and logic in configure would need to be more complex. Please confirm.

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Re: [Qemu-devel] [PATCH, RFC] ld flag --warn-common

[Ben Taylor]

On Sun, Sep 7, 2008 at 4:24 AM, Blue Swirl <blauwirbel@gmail.com> wrote:
> Hi,
>
> These trivial patches enable linker flag --warn-common and fix the
> warnings caused by enabling the flag.
>
> I think on some platforms (Solaris?) the linker used by gcc is not GNU
> ld. If this is true, the patch would break compilation on those hosts
> and logic in configure would need to be more complex. Please confirm.

yes, Solaris does not use gnu ld, it uses it's own linker.

Ben

Re: [Qemu-devel] [PATCH, RFC] ld flag --warn-common

[Blue Swirl]

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On 9/7/08, Ben Taylor <bentaylor.solx86@gmail.com> wrote:
> On Sun, Sep 7, 2008 at 4:24 AM, Blue Swirl <blauwirbel@gmail.com> wrote:
>  > Hi,
>  >
>  > These trivial patches enable linker flag --warn-common and fix the
>  > warnings caused by enabling the flag.
>  >
>  > I think on some platforms (Solaris?) the linker used by gcc is not GNU
>  > ld. If this is true, the patch would break compilation on those hosts
>  > and logic in configure would need to be more complex. Please confirm.
>
>
> yes, Solaris does not use gnu ld, it uses it's own linker.

Could you test if with this patch applied, "other ld" is printed when
configuring?

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Re: [Qemu-devel] [PATCH, RFC] ld flag --warn-common

[Ben Taylor]

On Sun, Sep 7, 2008 at 8:30 AM, Blue Swirl <blauwirbel@gmail.com> wrote:
> On 9/7/08, Ben Taylor <bentaylor.solx86@gmail.com> wrote:
>> On Sun, Sep 7, 2008 at 4:24 AM, Blue Swirl <blauwirbel@gmail.com> wrote:
>>  > Hi,
>>  >
>>  > These trivial patches enable linker flag --warn-common and fix the
>>  > warnings caused by enabling the flag.
>>  >
>>  > I think on some platforms (Solaris?) the linker used by gcc is not GNU
>>  > ld. If this is true, the patch would break compilation on those hosts
>>  > and logic in configure would need to be more complex. Please confirm.
>>
>>
>> yes, Solaris does not use gnu ld, it uses it's own linker.
>
> Could you test if with this patch applied, "other ld" is printed when
> configuring?

Confirmed that it prints "other ld" on Solaris.

Ben

Re: [Qemu-devel] [PATCH, RFC] ld flag --warn-common

[Blue Swirl]

On 9/9/08, Ben Taylor <bentaylor.solx86@gmail.com> wrote:
> On Sun, Sep 7, 2008 at 8:30 AM, Blue Swirl <blauwirbel@gmail.com> wrote:
>  > On 9/7/08, Ben Taylor <bentaylor.solx86@gmail.com> wrote:
>  >> On Sun, Sep 7, 2008 at 4:24 AM, Blue Swirl <blauwirbel@gmail.com> wrote:
>  >>  > Hi,
>  >>  >
>  >>  > These trivial patches enable linker flag --warn-common and fix the
>  >>  > warnings caused by enabling the flag.
>  >>  >
>  >>  > I think on some platforms (Solaris?) the linker used by gcc is not GNU
>  >>  > ld. If this is true, the patch would break compilation on those hosts
>  >>  > and logic in configure would need to be more complex. Please confirm.
>  >>
>  >>
>  >> yes, Solaris does not use gnu ld, it uses it's own linker.
>  >
>  > Could you test if with this patch applied, "other ld" is printed when
>  > configuring?
>
>
> Confirmed that it prints "other ld" on Solaris.

Thanks for testing, I'll prepare an updated version.

Re: [Qemu-devel] [PATCH, RFC] ld flag --warn-common

[Blue Swirl]

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On 9/9/08, Blue Swirl <blauwirbel@gmail.com> wrote:
> On 9/9/08, Ben Taylor <bentaylor.solx86@gmail.com> wrote:
>  > On Sun, Sep 7, 2008 at 8:30 AM, Blue Swirl <blauwirbel@gmail.com> wrote:
>  >  > On 9/7/08, Ben Taylor <bentaylor.solx86@gmail.com> wrote:
>  >  >> On Sun, Sep 7, 2008 at 4:24 AM, Blue Swirl <blauwirbel@gmail.com> wrote:
>  >  >>  > Hi,
>  >  >>  >
>  >  >>  > These trivial patches enable linker flag --warn-common and fix the
>  >  >>  > warnings caused by enabling the flag.
>  >  >>  >
>  >  >>  > I think on some platforms (Solaris?) the linker used by gcc is not GNU
>  >  >>  > ld. If this is true, the patch would break compilation on those hosts
>  >  >>  > and logic in configure would need to be more complex. Please confirm.
>  >  >>
>  >  >>
>  >  >> yes, Solaris does not use gnu ld, it uses it's own linker.
>  >  >
>  >  > Could you test if with this patch applied, "other ld" is printed when
>  >  > configuring?
>  >
>  >
>  > Confirmed that it prints "other ld" on Solaris.
>
>
> Thanks for testing, I'll prepare an updated version.

Here they are. I think I'll commit them in a few days unless there are
objections.

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Re: [Qemu-devel] [PATCH, RFC] ld flag --warn-common

[Kirill A. Shutemov]

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On Sun, Sep 07, 2008 at 11:24:37AM +0300, Blue Swirl wrote:
> Hi,
> 
> These trivial patches enable linker flag --warn-common and fix the
> warnings caused by enabling the flag.

This flag cause a lot of warning on my machine, even with trivial program.

$ cat 1.c
#include <stdio.h>

int main()
{
        printf("test\n");
        return 0;
}
$ gcc -Wl,--warn-common -static 1.c 
/usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtoul.o): warning: multiple common of `_nl_category_name_idxs'
/usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
/usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol_l.o): warning: multiple common of `_nl_category_name_idxs'
/usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
/usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtoul_l.o): warning: multiple common of `_nl_category_name_idxs'
/usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
/usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(vfprintf.o): warning: multiple common of `_nl_category_name_idxs'
/usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here

...and so on.


Is it problem with my toolchain? What is your testing environment?

-- 
Regards,  Kirill A. Shutemov
 + Belarus, Minsk
 + ALT Linux Team, http://www.altlinux.com/

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Re: [Qemu-devel] [PATCH, RFC] ld flag --warn-common

[Blue Swirl]

On 9/19/08, Kirill A. Shutemov <kirill@shutemov.name> wrote:
> On Sun, Sep 07, 2008 at 11:24:37AM +0300, Blue Swirl wrote:
>  > Hi,
>  >
>  > These trivial patches enable linker flag --warn-common and fix the
>  > warnings caused by enabling the flag.
>
>
> This flag cause a lot of warning on my machine, even with trivial program.
>
>  $ cat 1.c
>  #include <stdio.h>
>
>  int main()
>  {
>         printf("test\n");
>         return 0;
>  }
>  $ gcc -Wl,--warn-common -static 1.c
>  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtoul.o): warning: multiple common of `_nl_category_name_idxs'
>  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
>  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol_l.o): warning: multiple common of `_nl_category_name_idxs'
>  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
>  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtoul_l.o): warning: multiple common of `_nl_category_name_idxs'
>  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
>  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(vfprintf.o): warning: multiple common of `_nl_category_name_idxs'
>  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
>
>  ...and so on.
>
>
>  Is it problem with my toolchain? What is your testing environment?

I get no warnings for Qemu build on Debian i386, amd64
(stable/unstable), Sparc32, Sparc64 or on OpenBSD/Sparc64. Your
program produces one warning on Debian stable (all hosts except no
warnings on arm), no warnings on Debian amd64 unstable or OpenBSD.

Re: [Qemu-devel] [PATCH, RFC] ld flag --warn-common

[Kirill A. Shutemov]

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On Sat, Sep 20, 2008 at 10:49:36AM +0300, Blue Swirl wrote:
> On 9/19/08, Kirill A. Shutemov <kirill@shutemov.name> wrote:
> > On Sun, Sep 07, 2008 at 11:24:37AM +0300, Blue Swirl wrote:
> >  > Hi,
> >  >
> >  > These trivial patches enable linker flag --warn-common and fix the
> >  > warnings caused by enabling the flag.
> >
> >
> > This flag cause a lot of warning on my machine, even with trivial program.
> >
> >  $ cat 1.c
> >  #include <stdio.h>
> >
> >  int main()
> >  {
> >         printf("test\n");
> >         return 0;
> >  }
> >  $ gcc -Wl,--warn-common -static 1.c
> >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtoul.o): warning: multiple common of `_nl_category_name_idxs'
> >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
> >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol_l.o): warning: multiple common of `_nl_category_name_idxs'
> >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
> >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtoul_l.o): warning: multiple common of `_nl_category_name_idxs'
> >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
> >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(vfprintf.o): warning: multiple common of `_nl_category_name_idxs'
> >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
> >
> >  ...and so on.
> >
> >
> >  Is it problem with my toolchain? What is your testing environment?
> 
> I get no warnings for Qemu build on Debian i386, amd64
> (stable/unstable), Sparc32, Sparc64 or on OpenBSD/Sparc64. Your
> program produces one warning on Debian stable (all hosts except no
> warnings on arm), no warnings on Debian amd64 unstable or OpenBSD.

I've got a lot of warnings on ALT Linux x86_64 and Ubuntu x86_64. Both
with gcc 4.1.2. Are you sure that you test static build?

-- 
Regards,  Kirill A. Shutemov
 + Belarus, Minsk
 + ALT Linux Team, http://www.altlinux.com/

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Re: [Qemu-devel] [PATCH, RFC] ld flag --warn-common

[Blue Swirl]

On 9/22/08, Kirill A. Shutemov <kirill@shutemov.name> wrote:
> On Sat, Sep 20, 2008 at 10:49:36AM +0300, Blue Swirl wrote:
>  > On 9/19/08, Kirill A. Shutemov <kirill@shutemov.name> wrote:
>  > > On Sun, Sep 07, 2008 at 11:24:37AM +0300, Blue Swirl wrote:
>  > >  > Hi,
>  > >  >
>  > >  > These trivial patches enable linker flag --warn-common and fix the
>  > >  > warnings caused by enabling the flag.
>  > >
>  > >
>  > > This flag cause a lot of warning on my machine, even with trivial program.
>  > >
>  > >  $ cat 1.c
>  > >  #include <stdio.h>
>  > >
>  > >  int main()
>  > >  {
>  > >         printf("test\n");
>  > >         return 0;
>  > >  }
>  > >  $ gcc -Wl,--warn-common -static 1.c
>  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtoul.o): warning: multiple common of `_nl_category_name_idxs'
>  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
>  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol_l.o): warning: multiple common of `_nl_category_name_idxs'
>  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
>  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtoul_l.o): warning: multiple common of `_nl_category_name_idxs'
>  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
>  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(vfprintf.o): warning: multiple common of `_nl_category_name_idxs'
>  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
>  > >
>  > >  ...and so on.
>  > >
>  > >
>  > >  Is it problem with my toolchain? What is your testing environment?
>  >
>  > I get no warnings for Qemu build on Debian i386, amd64
>  > (stable/unstable), Sparc32, Sparc64 or on OpenBSD/Sparc64. Your
>  > program produces one warning on Debian stable (all hosts except no
>  > warnings on arm), no warnings on Debian amd64 unstable or OpenBSD.
>
>
> I've got a lot of warnings on ALT Linux x86_64 and Ubuntu x86_64. Both
>  with gcc 4.1.2. Are you sure that you test static build?

$ gcc -Wl,--warn-common -static main.c
/usr/lib/gcc/x86_64-linux-gnu/4.1.2/../../../../lib64/libc.a(dl-open.o):
warning: definition of `_dl_tls_static_size' overriding common
/usr/lib/gcc/x86_64-linux-gnu/4.1.2/../../../../lib64/libc.a(libc-tls.o):
warning: common is here
$ cat main.c
#include <stdio.h>

int main()
{
       printf("test\n");
       return 0;
}

Re: [Qemu-devel] [PATCH, RFC] ld flag --warn-common

[Kirill A. Shutemov]

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On Mon, Sep 22, 2008 at 07:24:27PM +0300, Blue Swirl wrote:
> On 9/22/08, Kirill A. Shutemov <kirill@shutemov.name> wrote:
> > On Sat, Sep 20, 2008 at 10:49:36AM +0300, Blue Swirl wrote:
> >  > On 9/19/08, Kirill A. Shutemov <kirill@shutemov.name> wrote:
> >  > > On Sun, Sep 07, 2008 at 11:24:37AM +0300, Blue Swirl wrote:
> >  > >  > Hi,
> >  > >  >
> >  > >  > These trivial patches enable linker flag --warn-common and fix the
> >  > >  > warnings caused by enabling the flag.
> >  > >
> >  > >
> >  > > This flag cause a lot of warning on my machine, even with trivial program.
> >  > >
> >  > >  $ cat 1.c
> >  > >  #include <stdio.h>
> >  > >
> >  > >  int main()
> >  > >  {
> >  > >         printf("test\n");
> >  > >         return 0;
> >  > >  }
> >  > >  $ gcc -Wl,--warn-common -static 1.c
> >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtoul.o): warning: multiple common of `_nl_category_name_idxs'
> >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
> >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol_l.o): warning: multiple common of `_nl_category_name_idxs'
> >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
> >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtoul_l.o): warning: multiple common of `_nl_category_name_idxs'
> >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
> >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(vfprintf.o): warning: multiple common of `_nl_category_name_idxs'
> >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
> >  > >
> >  > >  ...and so on.
> >  > >
> >  > >
> >  > >  Is it problem with my toolchain? What is your testing environment?
> >  >
> >  > I get no warnings for Qemu build on Debian i386, amd64
> >  > (stable/unstable), Sparc32, Sparc64 or on OpenBSD/Sparc64. Your
> >  > program produces one warning on Debian stable (all hosts except no
> >  > warnings on arm), no warnings on Debian amd64 unstable or OpenBSD.
> >
> >
> > I've got a lot of warnings on ALT Linux x86_64 and Ubuntu x86_64. Both
> >  with gcc 4.1.2. Are you sure that you test static build?
> 
> $ gcc -Wl,--warn-common -static main.c
> /usr/lib/gcc/x86_64-linux-gnu/4.1.2/../../../../lib64/libc.a(dl-open.o):
> warning: definition of `_dl_tls_static_size' overriding common
> /usr/lib/gcc/x86_64-linux-gnu/4.1.2/../../../../lib64/libc.a(libc-tls.o):
> warning: common is here
> $ cat main.c
> #include <stdio.h>
> 
> int main()
> {
>        printf("test\n");
>        return 0;
> }

I think --warn-common shouldn't be added to LDFLAGS, when we build static
qemu.

-- 
Regards,  Kirill A. Shutemov
 + Belarus, Minsk
 + ALT Linux Team, http://www.altlinux.com/

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Re: [Qemu-devel] [PATCH, RFC] ld flag --warn-common

[Blue Swirl]

On 9/22/08, Kirill A. Shutemov <kirill@shutemov.name> wrote:
> On Mon, Sep 22, 2008 at 07:24:27PM +0300, Blue Swirl wrote:
>  > On 9/22/08, Kirill A. Shutemov <kirill@shutemov.name> wrote:
>  > > On Sat, Sep 20, 2008 at 10:49:36AM +0300, Blue Swirl wrote:
>  > >  > On 9/19/08, Kirill A. Shutemov <kirill@shutemov.name> wrote:
>  > >  > > On Sun, Sep 07, 2008 at 11:24:37AM +0300, Blue Swirl wrote:
>  > >  > >  > Hi,
>  > >  > >  >
>  > >  > >  > These trivial patches enable linker flag --warn-common and fix the
>  > >  > >  > warnings caused by enabling the flag.
>  > >  > >
>  > >  > >
>  > >  > > This flag cause a lot of warning on my machine, even with trivial program.
>  > >  > >
>  > >  > >  $ cat 1.c
>  > >  > >  #include <stdio.h>
>  > >  > >
>  > >  > >  int main()
>  > >  > >  {
>  > >  > >         printf("test\n");
>  > >  > >         return 0;
>  > >  > >  }
>  > >  > >  $ gcc -Wl,--warn-common -static 1.c
>  > >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtoul.o): warning: multiple common of `_nl_category_name_idxs'
>  > >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
>  > >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol_l.o): warning: multiple common of `_nl_category_name_idxs'
>  > >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
>  > >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtoul_l.o): warning: multiple common of `_nl_category_name_idxs'
>  > >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
>  > >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(vfprintf.o): warning: multiple common of `_nl_category_name_idxs'
>  > >  > >  /usr/lib64/gcc/x86_64-alt-linux/4.1.2/../../../../lib64/libc.a(strtol.o): warning: previous common is here
>  > >  > >
>  > >  > >  ...and so on.
>  > >  > >
>  > >  > >
>  > >  > >  Is it problem with my toolchain? What is your testing environment?
>  > >  >
>  > >  > I get no warnings for Qemu build on Debian i386, amd64
>  > >  > (stable/unstable), Sparc32, Sparc64 or on OpenBSD/Sparc64. Your
>  > >  > program produces one warning on Debian stable (all hosts except no
>  > >  > warnings on arm), no warnings on Debian amd64 unstable or OpenBSD.
>  > >
>  > >
>  > > I've got a lot of warnings on ALT Linux x86_64 and Ubuntu x86_64. Both
>  > >  with gcc 4.1.2. Are you sure that you test static build?
>  >
>  > $ gcc -Wl,--warn-common -static main.c
>  > /usr/lib/gcc/x86_64-linux-gnu/4.1.2/../../../../lib64/libc.a(dl-open.o):
>  > warning: definition of `_dl_tls_static_size' overriding common
>  > /usr/lib/gcc/x86_64-linux-gnu/4.1.2/../../../../lib64/libc.a(libc-tls.o):
>  > warning: common is here
>  > $ cat main.c
>  > #include <stdio.h>
>  >
>  > int main()
>  > {
>  >        printf("test\n");
>  >        return 0;
>  > }
>
>
> I think --warn-common shouldn't be added to LDFLAGS, when we build static
>  qemu.

Another solution would be to add a configure time check if the system
libraries suck or not. Though these are only warnings and you seem to
be the only person complaining.