message: build: eliminate GCC9 warning from sift.simd.hpp
diff: @@ -807,11 +807,18 @@ if( dstMat.type() == CV_32F )
  __dst = v_min(v_max(v_cvt_f32(v_round(__dst * __nrm2)), __min), __max);
  v_store(dst + k, __dst);
  }
  +#endif
  +#if defined(__GNUC__) && __GNUC__ >= 9
  +#pragma GCC diagnostic push
  +#pragma GCC diagnostic ignored "-Waggressive-loop-optimizations" // iteration XX invokes undefined behavior
  #endif
  for( ; k < len; k++ )
  {
  dst[k] = saturate_cast<uchar>(rawDst[k]*nrm2);
  }
  +#if defined(__GNUC__) && __GNUC__ >= 9
  +#pragma GCC diagnostic pop
  +#endif
  }
  else // CV_8U
  {
  @@ -831,9 +838,8 @@ else // CV_8U
  #endif
  #if defined(__GNUC__) && __GNUC__ >= 9
  -// avoid warning "iteration 7 invokes undefined behavior" on Linux ARM64
  #pragma GCC diagnostic push
  -#pragma GCC diagnostic ignored "-Waggressive-loop-optimizations"
  +#pragma GCC diagnostic ignored "-Waggressive-loop-optimizations" // iteration XX invokes undefined behavior
  #endif
  for( ; k < len; k++ )
  {
  