Miguel Saldivar

I made a pr for the first issue 😸

Looks like this is now: ``` decltype (((std::__1::forward)({parm#1}))(((std::__1::forward)({parm#2}))...)) std::__1::__invoke(CallBackTimer::start(int, std::__1::function)::{lambda()#1}&&, &&) ```

`_Z3MinIiiEDTqultfp_fp0_cl7forwardIT_Efp_Ecl7forwardIT0_Efp0_EEOS0_OS1_` demangles the same as `libiberty` now, but `_Z3abcDTqult3def3ghi3jkl3mnoE` still does not. :/

Only `llvm-cxxfilt` has implemented the new c++20 lambda expressions: https://reviews.llvm.org/rL371273

@mstange that version of `c++filt` is a fork from apple that is from around ~2005. It internally calls `__cxa_demangle` which on an apple machine uses llvm's `libc++` rather than gcc's...