libswscale/yuv2rgb.c:841: error: Uninitialized Value
  The value read from abase was never initialized.

libswscale/yuv2rgb.c:841:36: 
839.             unsigned yval       = av_clip_uint8((yb + 0x8000) >> 16);
840.             y_table32[i]        = (yval << rbase) +
841.                                   (needAlpha ? 0 : (255u << abase));
                                        ^
842.             y_table32[i + 1024] =  yval << gbase;
843.             y_table32[i + 2048] =  yval << bbase;
