[Bug c++/87322] [8/9 Regression] GCC fails to parse captured lambda of 2nd inner lambda if the captured lambda has "," (having 2 arguments)

[aoliva at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87322

--- Comment #5 from Alexandre Oliva <aoliva at gcc dot gnu.org> ---
Created attachment 45614
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=45614&action=edit
Candidate patch

Besides the cp_unevaluated_operand issue that Jakub mentioned, that causes parm
lists to be incompletely tsubsted, we needed to arrange for the tsubsted lambda
expr and type to be reused: the expr appears both in a decltype type in the
capture variable and in its initializer.