Re: [Qemu-devel] [PATCH v2] build: include sys/sysmacros.h for major() and minor()

[Peter Maydell]

On 28 December 2016 at 16:10, Eric Blake <address@hidden> wrote:
> On 12/28/2016 08:53 AM, Christopher Covington wrote:
>> The definition of the major() and minor() macros are moving within glibc to
>> <sys/sysmacros.h>. Include this header to avoid the following sorts of
>> build-stopping messages:
>>
>
>> The additional include allows the build to complete on Fedora 26 (Rawhide)
>> with glibc version 2.24.90.
>>
>> Signed-off-by: Christopher Covington <address@hidden>
>> ---
>>  include/sysemu/os-posix.h | 1 +
>>  1 file changed, 1 insertion(+)
>>
>> diff --git a/include/sysemu/os-posix.h b/include/sysemu/os-posix.h
>> index b0a6c0695b..772d58f7ed 100644
>> --- a/include/sysemu/os-posix.h
>> +++ b/include/sysemu/os-posix.h
>> @@ -28,6 +28,7 @@
>>
>>  #include <sys/mman.h>
>>  #include <sys/socket.h>
>> +#include <sys/sysmacros.h>
>
> I repeat what I said on v1:
>
> Works for glibc; but <sys/sysmacros.h> is non-standard and not present
> on some other systems, so this may fail to build elsewhere.  You'll
> probably need a configure probe.  Autoconf also says that some platforms
> have <sys/mkdev.h> instead of <sys/sysmacros.h> (per its AC_HEADER_MAJOR
> macro).

Also this seems straightforwardly like a bug in glibc: it shouldn't
be making this kind of breaking change. makedev(3) on my Linux box
says nothing about needing sysmacros.h for these.

thanks
-- PMM