[Bug c++/107550] New: incorrect templated lambda mangling

[nathan at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107550

            Bug ID: 107550
           Summary: incorrect templated lambda mangling
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: nathan at gcc dot gnu.org
  Target Milestone: ---

I got something wrong in template lambda manglings, discovered when working on
the demangler (uncommitted).  Confirmed with clang.  We get the wrong mangling,
somehow losing the template-head of the lambda.

template<typename T> class X;

inline void f ()
{
  auto l3 = []<typename T>(X<T> *, X<int> *) {};

  l3 ((X<char> *)nullptr, nullptr);
  // _ZZ1fvENKUlTyP1XIT_EPS_IiEE _clIcEEDaS2_S4_  Correct
  // _ZZ1fvENKUl  P1XIT_EPS_IiEE0_clIcEEDaS2_S4_  Wrong
}

void a () 
{
  f ();
}