Re: [Qemu-devel] [PATCH] mingw: fix build on Fedora 22

["Denis V. Lunev" <den@openvz.org>]

On 09/22/2015 04:48 PM, Daniel P. Berrange wrote:
> On Tue, Sep 22, 2015 at 04:38:31PM +0300, Michael S. Tsirkin wrote:
>> mingw on Fedora 22 replaces localtime_r and gmtime_r
>> macros with posix compliant functions in time.h.
>>
>> These conflict with QEMU supplied ones.
>>
>> Detect this and avoid overriding them.
>>
>> We also need to define POSIX_C_SOURCE before including
>> time.h for the first time, to make sure these
>> are available to all users.
>>
>> Reported-by: Stefan Hajnoczi <stefanha@gmail.com>
>> Cc: Stefan Weil <sw@weilnetz.de>
>> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
>> ---
>>   include/qemu/osdep.h      | 1 +
>>   include/sysemu/os-win32.h | 6 ++++++
>>   util/oslib-win32.c        | 4 ++++
>>   3 files changed, 11 insertions(+)
>>
>> diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h
>> index ab3c876..9920ac3 100644
>> --- a/include/qemu/osdep.h
>> +++ b/include/qemu/osdep.h
>> @@ -25,6 +25,7 @@
>>   #ifndef QEMU_OSDEP_H
>>   #define QEMU_OSDEP_H
>>   
>> +#define _POSIX_C_SOURCE 200809L
>>   #include "config-host.h"
>>   #include "qemu/compiler.h"
>>   #include <stdarg.h>
>> diff --git a/include/sysemu/os-win32.h b/include/sysemu/os-win32.h
>> index 706d85a..74230e7 100644
>> --- a/include/sysemu/os-win32.h
>> +++ b/include/sysemu/os-win32.h
>> @@ -72,11 +72,17 @@
>>   #define sigsetjmp(env, savemask) setjmp(env)
>>   #define siglongjmp(env, val) longjmp(env, val)
>>   
>> +#ifdef gmtime_r
>>   /* Missing POSIX functions. Don't use MinGW-w64 macros. */
>>   #undef gmtime_r
>> +#define QEMU_NEED_GMTIME_R
>>   struct tm *gmtime_r(const time_t *timep, struct tm *result);
>> +#endif
> I don't think this is right. There are three possibilities
> with mingw
>
>   - No gmtime_r at all  - need replacement
>   - gmtime_r defined as a macro - need replacement
>   - gmtime_r defined as a function - nothing needed
>
> With this change of yours, if gmtime_r is defined as a macro
> QEMU will provide its own replacement. If gmtime_r is not
> defined at all, then QEMU doesn't provide its replacement
> which is wrong. I believe the change I previously proposed
> works in all three cases
>
> https://lists.gnu.org/archive/html/qemu-devel/2015-09/msg01926.html
indeed, this looks better to me.

Den