[FFmpeg-devel] [PATCH] Remove printf format string errors in windows builds

Larry Robinson silver-dad
Mon Jan 24 00:36:52 CET 2011

On 1/23/2011 3:05 PM, Jean-Baptiste Kempf wrote:
> Hello,
> On Sun, Jan 23, 2011 at 02:58:23PM -0800, Larry Robinson wrote :
>> Both Mingw32 and Mingw64 rely on msvcrt.dll to interpret format strings
>> for printf, sscanf, etc. and so gcc doesn't recognize `t' or `z' width
>> specifications for 64-bit types on windows. It therefore produces warnings
>> and incorrect code for format strings containing `%td', `%zd', ...
> Are you sure you shouldn't just use -D__USE_MINGW_ANSI_STDIO=1
> Best Regards,
Thank you, I was not aware of that.  I am actually building 64-bit 
libraries using mingw-w64, and unfortunately __USE_MINGW_ANSI_STDIO is 
not fully implemented there. On their support wiki 
it states:

"Currently only printf family is implemented and scanf implementation is 
waiting for volunteer."

Sure enough, I tried it and still get the warning.  Given that, what's 
the best way to fix this on x86_64-w64-mingw32?

Larry Robinson

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