Xcode debugger sometimes doesn't display variable values?

Question

This happens to me pretty often. For example, right now I have the debugger stopped at a breakpoint in a method . . . and it isn\'t displaying any variable values at all.

Answer 1

There is a situation I have seen where Xcode can't cope with return value optimisation (RVO) -- if the compiler decides to apply RVO to a variable then it may not appear in the variables list. You can disable this in g++ and clang with the compiler flag -fno-elide-constructors

See also Understanding eliding rules with regard to c++11