Demangling decltype failure case

[ElykDeer]

Internal tests show several similar cases, but here's one example case I can share publicly:

Mangled name:

_ZSt12__miter_baseIPlEDTcl12__miter_basecldtfp_4baseEEESt13move_iteratorIT_E

What we produce:

(__miter_base, ((base).(__miter_base))) std::__miter_base<int32_t*>(std::move_iterator<int32_t*>)

Possible real result:

decltype (__miter_base(({parm#1}.base)())) std::__miter_base<int32_t*>(std::move_iterator<int32_t*>)