During code analysis, PVS-Studio analyzes the data flow and operates variable values. Values are taken from constants or derived from conditional expressions. We call them virtual values. Recently, we have refined them in order to work with multi-character constants and this has become the reason to create a new diagnostic rule.
Multi-character-literals are implementation-defined, so different compilers can encode them in different ways. For example, GCC and Clang set a value, based on the order of the symbols in the literal, while MSVC moves them depending on the symbol's type (regular or escape).