Checking qAbs preconditions reveals that several places into Qt are calling it with minimal values, causing UB. Those places do not actually need that the absolute value is of the same type as the parameter. Therefore, introduce qUnsignedAbs, which is like qAbs() but whose return type is always unsigned, and therefore can accept everything. This function is private; I don't want to encourage users to rely on our extension. Aggressively cherry picking because this will be needed in subsequent bugfixes. Change-Id: I2047768a5fd35f12bf898ca8c2008813434edd8d Pick-to: 6.9 6.8 6.5 6.2 Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>