https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84978
--- Comment #4 from Marek Polacek <mpolacek at gcc dot gnu.org> --- This ICE apparently depends on whether we perform NRVO or not. If the size of S is <=16B we pass it in registers and it compiles fine. But if the size of S is >16B, then we pass in memory, and we NRV-optimize. That means that s.fn (); is after finalize_nrv <retval>.fn (); Then the newly added call to cp_get_callee_fndecl in cp_genericize_r calls maybe_constant_init, which ends up evaluating <retval>, but it's not in the hash map, so we crash here: 4111 /* We ask for an rvalue for the RESULT_DECL when indirecting 4112 through an invisible reference, or in named return value 4113 optimization. */ 4114 return (*ctx->values->get (t));
