Currently, IDA Pro demangles MSVC vtordisp{4294967292,0} with an unsigned integer for vtordisp displacement. This isn’t very helpful, as -4 is the actual value as its signed, which also makes it easier to read and reason about.
how does undname print it?
Both latest Microsoft (undname.exe) and LLVM (llvm-undname.exe) output negative number, though some Microsoft undname versions incorrectly output large unsigned number