Interesting, until very recently I was writing a whole bunch of C++ at Google but I can't recall any such restriction. Most internal data structures at Google are expressed as protocol buffers and surely these support unsigned integers. In fact if someone suggested that a view counter should be signed that would invite a snark (kind of Google's specialty) like 'can it ever be negative'?

[One problem with unsigned integers in protocol buffers is that some supported languages like Python have no concept of signed/unsigned integers. Which is why for example Thrift does not support that distinction. This has nothing to do with C++ though.]

Why not both? Fix the bug, then celebrate.