Various double-to-string converters carefully omit the sign from -0.0, for which they need to test whether the double is zero. This was tested by a function that looked at the bytes of the double in an endian-specific way. Packaging a comparison to zero in a function seems to avoid the compiler warnings over double-comparison, so retain the function but make it simpler. The only available benchmark (QString's number_double benchmark) consistently shows a negligible improvement in performance. Change-Id: Id994177e21e4770ced904881d7e84a95cb727605 Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>